WorldWideScience

Sample records for regulates hiv-1 ltr

  1. Nuclear Matrix protein SMAR1 represses HIV-1 LTR mediated transcription through chromatin remodeling

    International Nuclear Information System (INIS)

    Sreenath, Kadreppa; Pavithra, Lakshminarasimhan; Singh, Sandeep; Sinha, Surajit; Dash, Prasanta K.; Siddappa, Nagadenahalli B.; Ranga, Udaykumar; Mitra, Debashis; Chattopadhyay, Samit

    2010-01-01

    Nuclear Matrix and MARs have been implicated in the transcriptional regulation of host as well as viral genes but their precise role in HIV-1 transcription remains unclear. Here, we show that > 98% of HIV sequences contain consensus MAR element in their promoter. We show that SMAR1 binds to the LTR MAR and reinforces transcriptional silencing by tethering the LTR MAR to nuclear matrix. SMAR1 associated HDAC1-mSin3 corepressor complex is dislodged from the LTR upon cellular activation by PMA/TNFα leading to an increase in the acetylation and a reduction in the trimethylation of histones, associated with the recruitment of RNA Polymerase II on the LTR. Overexpression of SMAR1 lead to reduction in LTR mediated transcription, both in a Tat dependent and independent manner, resulting in a decreased virion production. These results demonstrate the role of SMAR1 in regulating viral transcription by alternative compartmentalization of LTR between the nuclear matrix and chromatin.

  2. Cellular specificity of HIV-1 replication can be controlled by LTR sequences

    International Nuclear Information System (INIS)

    Reed-Inderbitzin, Edward; Maury, Wendy

    2003-01-01

    Two well-established determinants of retroviral tropism are envelope sequences that regulate entry and LTR sequences that can regulate viral expression in a cell-specific manner. Studies with human immunodeficiency virus-1 (HIV-1) have demonstrated that tropism of this virus maps primarily to variable envelope sequences. Studies have demonstrated that T cell and macrophage-specific transcription factor binding motifs exist in the upstream region of the LTR U3; however, the ability of the core enhancer/promoter proximal elements (two NF-κB and three Sp1 sites) to function well in macrophages and T cells have led many to conclude that HIV LTR sequences are not primary determinants of HIV tropism. To determine if cellular specificity could be imparted to HIV by the core enhancer elements, the enhancer/promoter proximal region of the HIV LTR was substituted with motifs that control gene expression in a myeloid-specific manner. The enhancer region from equine infectious anemia virus (EIAV) when substituted for the HIV enhancer/promoter proximal region was found to drive expression in a macrophage-specific manner and was responsive to HIV Tat. The addition of a 5' methylation-dependent binding site (MDBP) and a promoter proximal Sp1 motif increased expression without altering cellular specificity. Spacing between the promoter proximal region and the TATA box was also found to influence LTR activity. Infectivity studies using chimeric LTRs within the context of a dual-tropic infectious molecular clone established that these LTRs directed HIV replication and production of infectious virions in macrophages but not primary T cells or T cell lines. This investigation demonstrates that cellular specificity can be imparted onto HIV-1 replication at the level of viral transcription and not entry

  3. The dual action of poly(ADP-ribose polymerase -1 (PARP-1 inhibition in HIV-1 infection: HIV-1 LTR inhibition and diminution in Rho GTPase activity

    Directory of Open Access Journals (Sweden)

    Slava eRom

    2015-08-01

    Full Text Available The transcription of HIV-1 (HIV is regulated by complex mechanisms involving various cellular factors and virus-encoded transactivators. Poly(ADP-ribose polymerase 1 (PARP-1 inhibition has emerged recently as a potent anti-inflammatory tool, since PARP-1 is involved in the regulation of some genes through its interaction with various transcription factors. We propose a novel approach to diminish HIV replication via PARP-1 inhibition using human primary monocyte-derived macrophages (MDM as an in vitro model system. PARP-1 inhibitors were able to reduce HIV replication in MDM by 60-80% after 7 days infection. Long Terminal Repeat (LTR acts as a switch in virus replication and can be triggered by several agents such as: Tat, tumor necrosis factor α (TNFα, and phorbol 12-myristate 13-acetate (PMA. Overexpression of Tat in MDM transfected with an LTR reporter plasmid led to a 4.2-fold increase in LTR activation; PARP inhibition resulted in 70% reduction of LTR activity. LTR activity, which increased 3-fold after PMA or TNFα treatment, was reduced by PARP inhibition (by 85-95%. MDM treated with PARP inhibitors showed 90% reduction in NFκB activity (known to mediate PMA- and TNFα-induced HIV LTR activation. Cytoskeleton rearrangements are important in effective HIV-1 infection. PARP inactivation reduced actin cytoskeleton rearrangements by affecting Rho GTPase machinery. These findings suggest that HIV replication in MDM could be suppressed by PARP inhibition via NFκB suppression, diminution of LTR activation and its effects on the cytoskeleton. PARP appears to be essential for HIV replication and its inhibition may provide a potent approach to treatment of HIV infection.

  4. Alterations in HIV-1 LTR promoter activity during AIDS progression

    International Nuclear Information System (INIS)

    Hiebenthal-Millow, Kirsten; Greenough, Thomas C.; Bretttler, Doreen B.; Schindler, Michael; Wildum, Steffen; Sullivan, John L.; Kirchhoff, Frank

    2003-01-01

    HIV-1 variants evolving in AIDS patients frequently show increased replicative capacity compared to those present during early asymptomatic infection. It is known that late stage HIV-1 variants often show an expanded coreceptor tropism and altered Nef function. In the present study we investigated whether enhanced HIV-1 LTR promoter activity might also evolve during disease progression. Our results demonstrate increased LTR promoter activity after AIDS progression in 3 of 12 HIV-1-infected individuals studied. Further analysis revealed that multiple alterations in the U3 core-enhancer and in the transactivation-response (TAR) region seem to be responsible for the enhanced functional activity. Our findings show that in a subset of HIV-1-infected individuals enhanced LTR transcription contributes to the increased replicative potential of late stage virus isolates and might accelerate disease progression

  5. Rapid turnover of 2-LTR HIV-1 DNA during early stage of highly active antiretroviral therapy.

    Directory of Open Access Journals (Sweden)

    Weijun Zhu

    Full Text Available BACKGROUND: Despite prolonged treatment with highly active antiretroviral therapy (HAART, the infectious HIV-1 continues to replicate and resides latently in the resting memory CD4+ T lymphocytes, which blocks the eradication of HIV-1. The viral persistence of HIV-1 is mainly caused by its proviral DNA being either linear nonintegrated, circular nonintegrated, or integrated. Previous reports have largely focused on the dynamics of HIV-1 DNA from the samples collected with relatively long time intervals during the process of disease and HAART treatment, which may have missed the intricate changes during the intervals in early treatment. METHODOLOGY/PRINCIPAL FINDINGS: In this study, we investigated the dynamics of HIV-1 DNA in patients during the early phase of HARRT treatment. Using optimized real time PCR, we observed significant changes in 2-LTR during the first 12-week of treatment, while total and integrated HIV-1 DNA remained stable. The doubling time and half-life of 2-LTR were not correlated with the baseline and the rate of changes in plasma viral load and various CD4+ T-cell populations. Longitudinal analyses on 2-LTR sequences and plasma lipopolysaccharide (LPS levels did not reveal any significant changes in the same treatment period. CONCLUSIONS/SIGNIFICANCE: Our study revealed the rapid changes in 2-LTR concentration in a relatively large number of patients during the early HAART treatment. The rapid changes indicate the rapid infusion and clearance of cells bearing 2-LTR in the peripheral blood. Those changes are not expected to be caused by the blocking of viral integration, as our study did not include the integrase inhibitor raltegravir. Our study helps better understand the dynamics of HIV-DNA and its potential role as a biomarker for the diseases and for the treatment efficacy of HAART.

  6. Intracellular high mobility group B1 protein (HMGB1) represses HIV-1 LTR-directed transcription in a promoter- and cell-specific manner

    International Nuclear Information System (INIS)

    Naghavi, Mojgan H.; Nowak, Piotr; Andersson, Jan; Soennerborg, Anders; Yang Huan; Tracey, Kevin J.; Vahlne, Anders

    2003-01-01

    We investigated whether the high mobility group B 1 (HMGB1), an abundant nuclear protein in all mammalian cells, affects HIV-1 transcription. Intracellular expression of human HMGB1 repressed HIV-1 gene expression in epithelial cells. This inhibitory effect of HMGB1 was caused by repression of long terminal repeat (LTR)-mediated transcription. Other viral promoters/enhancers, including simian virus 40 or cytomegalovirus, were not inhibited by HMGB1. In addition, HMGB1 inhibition of HIV-1 subtype C expression was dependent on the number of NFκB sites in the LTR region. The inhibitory effect of HMGB1 on viral gene expression observed in HeLa cells was confirmed by an upregulation of viral replication in the presence of antisense HMGB1 in monocytic cells. In contrast to what was found in HeLa cells and monocytic cells, endogenous HMGB1 expression did not affect HIV-1 replication in unstimulated Jurkat cells. Thus, intracellular HMGB1 affects HIV-1 LTR-directed transcription in a promoter- and cell-specific manner

  7. Accurate episomal HIV 2-LTR circles quantification using optimized DNA isolation and droplet digital PCR.

    Science.gov (United States)

    Malatinkova, Eva; Kiselinova, Maja; Bonczkowski, Pawel; Trypsteen, Wim; Messiaen, Peter; Vermeire, Jolien; Verhasselt, Bruno; Vervisch, Karen; Vandekerckhove, Linos; De Spiegelaere, Ward

    2014-01-01

    In HIV-infected patients on combination antiretroviral therapy (cART), the detection of episomal HIV 2-LTR circles is a potential marker for ongoing viral replication. Quantification of 2-LTR circles is based on quantitative PCR or more recently on digital PCR assessment, but is hampered due to its low abundance. Sample pre-PCR processing is a critical step for 2-LTR circles quantification, which has not yet been sufficiently evaluated in patient derived samples. We compared two sample processing procedures to more accurately quantify 2-LTR circles using droplet digital PCR (ddPCR). Episomal HIV 2-LTR circles were either isolated by genomic DNA isolation or by a modified plasmid DNA isolation, to separate the small episomal circular DNA from chromosomal DNA. This was performed in a dilution series of HIV-infected cells and HIV-1 infected patient derived samples (n=59). Samples for the plasmid DNA isolation method were spiked with an internal control plasmid. Genomic DNA isolation enables robust 2-LTR circles quantification. However, in the lower ranges of detection, PCR inhibition caused by high genomic DNA load substantially limits the amount of sample input and this impacts sensitivity and accuracy. Moreover, total genomic DNA isolation resulted in a lower recovery of 2-LTR templates per isolate, further reducing its sensitivity. The modified plasmid DNA isolation with a spiked reference for normalization was more accurate in these low ranges compared to genomic DNA isolation. A linear correlation of both methods was observed in the dilution series (R2=0.974) and in the patient derived samples with 2-LTR numbers above 10 copies per million peripheral blood mononuclear cells (PBMCs), (R2=0.671). Furthermore, Bland-Altman analysis revealed an average agreement between the methods within the 27 samples in which 2-LTR circles were detectable with both methods (bias: 0.3875±1.2657 log10). 2-LTR circles quantification in HIV-infected patients proved to be more

  8. Marcadores virológicos no convencionales en pacientes infectados con el virus de la inmunodeficiencia humana: ADN HIV-T, ADN HIV- 2LTR y ARN de HIV Non conventional virological markers in HIV-infected patients: T-HIV DNA, 2LTR-HIV DNA and HIV RNA

    Directory of Open Access Journals (Sweden)

    Rosana Gariglio

    2004-10-01

    Full Text Available La terapia antirretroviral de alta eficacia (TAAE induce una reducción marcada y persistente de la viremia plasmática, contribuyendo a disminuir la mortalidad y morbilidad de los pacientes HIV-positivos. Así, la carga viral (CV es el método de referencia para evaluar la eficacia terapéutica. Sin embargo, aun en presencia de una TAAE eficiente no se ha logrado la erradicación viral. En este estudio analizamos la presencia del ADN total de HIV (ADN HIV-T, del ADN no integrado con 2LTR (ADN HIV-2LTR y del ARN de HIV, en un grupo de 55 pacientes HIV-positivos en distintos estadios clínicos, con y sin TAAE, mediante ensayos de PCR con revelado colorimétrico en microplaca, optimizados en nuestro laboratorio. La sensibilidad clínica del ARN del HIV fue evaluada con el bDNA, resultando del 74% y del 64%, respectivamente, con una concordancia del 85%. Este ensayo podría ser utilizado en el seguimiento de pacientes bajo TAAE. El ADN HIV-2LTR resultó positivo en el 54% aunque estuvo ausente en pacientes con elevada CV. Este marcador se consideraba un producto lábil y su presencia se asociaba a infección reciente. Sin embargo, actuales evidencias ponen en discusión su estabilidad por lo que su significado clínico debe ser reconsiderado. La ausencia del ADN HIV-2LTR en pacientes con CV detectable puede relacionarse con la heterogeneidad de la secuencia utilizada para su detección. El ADN HIV-T estuvo presente en el 100% de las muestras y resultaría relevante como marcador de remisión cuando se dispongan de terapias que efectivamente erradiquen la infección.Highly active antiretroviral therapy (HAART induces a persistent reduction of the plasmatic viremia, contributing to decrease mortality and morbidity of infected people with human immunodeficiency virus (HIV. Thus, viral load (VL is the reference method to evaluate therapy effectiveness. However, even in the presence of efficient HAART viral eradication was yet not achieved. In this

  9. Cocaine promotes both initiation and elongation phase of HIV-1 transcription by activating NF-κB and MSK1 and inducing selective epigenetic modifications at HIV-1 LTR

    International Nuclear Information System (INIS)

    Sahu, Geetaram; Farley, Kalamo; El-Hage, Nazira; Aiamkitsumrit, Benjamas; Fassnacht, Ryan; Kashanchi, Fatah; Ochem, Alex; Simon, Gary L.; Karn, Jonathan; Hauser, Kurt F.; Tyagi, Mudit

    2015-01-01

    Cocaine accelerates human immunodeficiency virus (HIV-1) replication by altering specific cell-signaling and epigenetic pathways. We have elucidated the underlying molecular mechanisms through which cocaine exerts its effect in myeloid cells, a major target of HIV-1 in central nervous system (CNS). We demonstrate that cocaine treatment promotes HIV-1 gene expression by activating both nuclear factor-kappa B (NF-ĸB) and mitogen- and stress-activated kinase 1 (MSK1). MSK1 subsequently catalyzes the phosphorylation of histone H3 at serine 10, and p65 subunit of NF-ĸB at 276th serine residue. These modifications enhance the interaction of NF-ĸB with P300 and promote the recruitment of the positive transcription elongation factor b (P-TEFb) to the HIV-1 LTR, supporting the development of an open/relaxed chromatin configuration, and facilitating the initiation and elongation phases of HIV-1 transcription. Results are also confirmed in primary monocyte derived macrophages (MDM). Overall, our study provides detailed insights into cocaine-driven HIV-1 transcription and replication. - Highlights: • Cocaine induces the initiation phase of HIV transcription by activating NF-ĸB. • Cocaine induced NF-ĸB phosphorylation promotes its interaction with P300. • Cocaine enhances the elongation phase of HIV transcription by stimulating MSK1. • Cocaine activated MSK1 catalyzes the phosphorylation of histone H3 at its Ser10. • Cocaine induced H3S10 phosphorylation facilitates the recruitment of P-TEFb at LTR

  10. Cocaine promotes both initiation and elongation phase of HIV-1 transcription by activating NF-κB and MSK1 and inducing selective epigenetic modifications at HIV-1 LTR

    Energy Technology Data Exchange (ETDEWEB)

    Sahu, Geetaram; Farley, Kalamo [Division of Infectious Diseases, Department of Medicine, George Washington University, Washington, DC (United States); El-Hage, Nazira [Virginia Commonwealth University, Richmond, VA (United States); Aiamkitsumrit, Benjamas; Fassnacht, Ryan [Division of Infectious Diseases, Department of Medicine, George Washington University, Washington, DC (United States); Kashanchi, Fatah [George Mason University, Manassas, VA (United States); Ochem, Alex [ICGEB, Wernher and Beit Building, Anzio Road, Observatory, 7925 Cape Town (South Africa); Simon, Gary L. [Division of Infectious Diseases, Department of Medicine, George Washington University, Washington, DC (United States); Karn, Jonathan [Case Western Reserve University, Cleveland, OH (United States); Hauser, Kurt F. [Virginia Commonwealth University, Richmond, VA (United States); Tyagi, Mudit, E-mail: tmudit@email.gwu.edu [Division of Infectious Diseases, Department of Medicine, George Washington University, Washington, DC (United States); Department of Microbiology, Immunology and Tropical Medicine, George Washington University, Washington, DC 20037 (United States)

    2015-09-15

    Cocaine accelerates human immunodeficiency virus (HIV-1) replication by altering specific cell-signaling and epigenetic pathways. We have elucidated the underlying molecular mechanisms through which cocaine exerts its effect in myeloid cells, a major target of HIV-1 in central nervous system (CNS). We demonstrate that cocaine treatment promotes HIV-1 gene expression by activating both nuclear factor-kappa B (NF-ĸB) and mitogen- and stress-activated kinase 1 (MSK1). MSK1 subsequently catalyzes the phosphorylation of histone H3 at serine 10, and p65 subunit of NF-ĸB at 276th serine residue. These modifications enhance the interaction of NF-ĸB with P300 and promote the recruitment of the positive transcription elongation factor b (P-TEFb) to the HIV-1 LTR, supporting the development of an open/relaxed chromatin configuration, and facilitating the initiation and elongation phases of HIV-1 transcription. Results are also confirmed in primary monocyte derived macrophages (MDM). Overall, our study provides detailed insights into cocaine-driven HIV-1 transcription and replication. - Highlights: • Cocaine induces the initiation phase of HIV transcription by activating NF-ĸB. • Cocaine induced NF-ĸB phosphorylation promotes its interaction with P300. • Cocaine enhances the elongation phase of HIV transcription by stimulating MSK1. • Cocaine activated MSK1 catalyzes the phosphorylation of histone H3 at its Ser10. • Cocaine induced H3S10 phosphorylation facilitates the recruitment of P-TEFb at LTR.

  11. The effects of multiple UV exposures on HIV-LTR (long terminal repeat) expression

    International Nuclear Information System (INIS)

    Schreck, S.; Milton, J.; Panozzo, J.; Libertin, C.R.; Woloschak, G.E.; Loyola Univ., Maywood, IL

    1995-01-01

    Previous studies have shown that cellular stress agents such as UV radiation induce transcription from the long terminal repeat (LTR) of the human immunodeficiency virus (HIV). Using HeLa cells stably transfected with the HIV-LTR sequence, which transcriptionally drives the chloramphenicol acetyl transferase (CAT) reporter gene, we examined the effects of multiple exposures to UVC (254 nm) on HIV-LTR-CAT expression. Low doses (≤ 5 J m -2 ) had no effect on CAT expression, but up to 29-fold induction was observed with 10 J m -2 when cells were harvested 48 h after completion of the exposure. Little difference was noted in induction levels when cells were exposed to one 25 J m -2 dose, viable cells were harvested at 24 h, 48 h or 72 h, and cell lysates were assayed for CAT expression. Two sequential 12.5 J m -2 exposures, given 24 h apart, resulted in an additive effect on CAT expression; these two exposures produced CAT activity equivalent to that induced following a single 25 J m -2 dose. Our data suggest that HIV-LTR requires a specific threshold UV dose in order to elicit induction; a maximal induction dose is also evident; exposures higher than this maximal dose contribute no more to HIV-LTR induction in viable cells. (author)

  12. Human Immunodeficiency Virus-Type 1 LTR DNA contains an intrinsic gene producing antisense RNA and protein products

    Directory of Open Access Journals (Sweden)

    Hsiao Chiu-Bin

    2006-11-01

    Full Text Available Abstract Background While viruses have long been shown to capitalize on their limited genomic size by utilizing both strands of DNA or complementary DNA/RNA intermediates to code for viral proteins, it has been assumed that human retroviruses have all their major proteins translated only from the plus or sense strand of RNA, despite their requirement for a dsDNA proviral intermediate. Several studies, however, have suggested the presence of antisense transcription for both HIV-1 and HTLV-1. More recently an antisense transcript responsible for the HTLV-1 bZIP factor (HBZ protein has been described. In this study we investigated the possibility of an antisense gene contained within the human immunodeficiency virus type 1 (HIV-1 long terminal repeat (LTR. Results Inspection of published sequences revealed a potential transcription initiator element (INR situated downstream of, and in reverse orientation to, the usual HIV-1 promoter and transcription start site. This antisense initiator (HIVaINR suggested the possibility of an antisense gene responsible for RNA and protein production. We show that antisense transcripts are generated, in vitro and in vivo, originating from the TAR DNA of the HIV-1 LTR. To test the possibility that protein(s could be translated from this novel HIV-1 antisense RNA, recombinant HIV antisense gene-FLAG vectors were designed. Recombinant protein(s were produced and isolated utilizing carboxy-terminal FLAG epitope (DYKDDDDK sequences. In addition, affinity-purified antisera to an internal peptide derived from the HIV antisense protein (HAP sequences identified HAPs from HIV+ human peripheral blood lymphocytes. Conclusion HIV-1 contains an antisense gene in the U3-R regions of the LTR responsible for both an antisense RNA transcript and proteins. This antisense transcript has tremendous potential for intrinsic RNA regulation because of its overlap with the beginning of all HIV-1 sense RNA transcripts by 25 nucleotides. The

  13. Interaction of the phospholipid scramblase 1 with HIV-1 Tat results in the repression of Tat-dependent transcription

    International Nuclear Information System (INIS)

    Kusano, Shuichi; Eizuru, Yoshito

    2013-01-01

    Highlights: •PLSCR1 specifically interacted with HIV-1 Tat in vitro and in vivo. •PLSCR1 repressed Tat-dependent transactivation of the HIV-1 LTR. •Suppression of PLSCR1 expression enhanced the levels of HIV-1 transcripts. •PLSCR1 reduced the nuclear localization of Tat. -- Abstract: Human phospholipid scramblase 1 (PLSCR1) is an interferon (IFN)-stimulated gene and possesses an IFN-mediated antiviral function. We show here that PLSCR1 directly interacts with human immunodeficiency virus type-1 (HIV-1) Tat. This interaction occurs both in vitro and in vivo through amino acids 160–250 of PLSCR1. Overexpression of PLSCR1 efficiently represses the Tat-dependent transactivation of the HIV-1 long terminal repeat (LTR) and reduces the nuclear translocation of Tat. In addition, shRNA-mediated suppression of endogenous PLSCR1 expression enhances the levels of gag mRNA in an HIV-1-infected T-cell line. These findings indicate that PLSCR1 negatively regulates the Tat-dependent transactivation of the HIV-1 LTR during HIV-1 infection

  14. Cocaine promotes both initiation and elongation phase of HIV-1 transcription by activating NF-κB and MSK1 and inducing selective epigenetic modifications at HIV-1 LTR

    Science.gov (United States)

    Sahu, Geetaram; Farley, Kalamo; El-Hage, Nazira; Aiamkitsumrit, Benjamas; Fassnacht, Ryan; Kashanchi, Fatah; Ochem, Alex; Simon, Gary L.; Karn, Jonathan; Hauser, Kurt F.; Tyagi, Mudit

    2015-01-01

    Cocaine accelerates human immunodeficiency virus (HIV-1) replication by altering specific cell-signaling and epigenetic pathways. We have elucidated the underlying molecular mechanisms through which cocaine exerts its effect in myeloid cells, a major target of HIV-1 in central nervous system (CNS). We demonstrate that cocaine treatment promotes HIV-1 gene expression by activating both nuclear factor-kappa B (NF-κB) and mitogen- and stress-activated kinase 1 (MSK1). MSK1 subsequently catalyzes the phosphorylation of histone H3 at serine 10, and p65 subunit of NF-κB at 276th serine residue. These modifications enhance the interaction of NF-κB with P300 and promote the recruitment of the positive transcription elongation factor b (P-TEFb) to the HIV-1 LTR, supporting the development of an open/relaxed chromatin configuration, and facilitating the initiation and elongation phases of HIV-1 transcription. Results are also confirmed in primary monocyte derived macrophages (MDM). Overall, our study provides detailed insights into cocaine-driven HIV-1 transcription and replication. PMID:25980739

  15. Receptor-targeted aptamer-siRNA conjugate-directed transcriptional regulation of HIV-1

    Science.gov (United States)

    Zhou, Jiehua; Lazar, Daniel; Li, Haitang; Xia, Xin; Satheesan, Sangeetha; Charlins, Paige; O'Mealy, Denis; Akkina, Ramesh; Saayman, Sheena; Weinberg, Marc S.; Rossi, John J.; Morris, Kevin V.

    2018-01-01

    Gene-based therapies represent a promising therapeutic paradigm for the treatment of HIV-1, as they have the potential to maintain sustained viral inhibition with reduced treatment interventions. Such an option may represent a long-term treatment alternative to highly active antiretroviral therapy. Methods: We previously described a therapeutic approach, referred to as transcriptional gene silencing (TGS), whereby small noncoding RNAs directly inhibit the transcriptional activity of HIV-1 by targeting sites within the viral promoter, specifically the 5' long terminal repeat (LTR). TGS differs from traditional RNA interference (RNAi) in that it is characterized by concomitant silent-state epigenetic marks on histones and DNA. To deliver TGS-inducing RNAs, we developed functional RNA conjugates based on the previously reported dual function of the gp120 (A-1) aptamer conjugated to 27-mer Dicer-substrate anti-HIV-1 siRNA (dsiRNA), LTR-362. Results: We demonstrate here that high levels of processed guide RNAs localize to the nucleus in infected T lymphoblastoid CEM cell line and primary human CD4+ T-cells. Treatment of the aptamer-siRNA conjugates induced TGS with an ~10-fold suppression of viral p24 levels as measured at day 12 post infection. To explore the silencing efficacy of aptamer-siRNA conjugates in vivo, HIV-1-infected humanized NOD/SCID/IL2 rγnull mice (hu-NSG) were treated with the aptamer-siRNA conjugates. Systemic delivery of the A-1-stick-LTR-362 27-mer siRNA conjugates suppressed HIV-1 infection and protected CD4+ T cell levels in viremia hu-NSG mice. Principle conclusions: Collectively these data suggest that the gp120 aptamer-dsiRNA conjugate design is suitable for systemic delivery of small RNAs that can be used to suppress HIV-1. PMID:29556342

  16. Selective histonedeacetylase inhibitor M344 intervenes in HIV-1 latency through increasing histone acetylation and activation of NF-kappaB.

    Directory of Open Access Journals (Sweden)

    Hao Ying

    Full Text Available Histone deacetylase (HDAC inhibitors present an exciting new approach to activate HIV production from latently infected cells to potentially enhance elimination of these cells and achieve a cure. M344, a novel HDAC inhibitor, shows robust activity in a variety of cancer cells and relatively low toxicity compared to trichostatin A (TSA. However, little is known about the effects and action mechanism of M344 in inducing HIV expression in latently infected cells.Using the Jurkat T cell model of HIV latency, we demonstrate that M344 effectively reactivates HIV-1 gene expression in latently infected cells. Moreover, M344-mediated activation of the latent HIV LTR can be strongly inhibited by a NF-κB inhibitor aspirin. We further show that M344 acts by increasing the acetylation of histone H3 and histone H4 at the nucleosome 1 (nuc-1 site of the HIV-1 long terminal repeat (LTR and by inducing NF-κB p65 nuclear translocation and direct RelA DNA binding at the nuc-1 region of the HIV-1 LTR. We also found that M344 synergized with prostratin to activate the HIV-1 LTR promoter in latently infected cells.These results suggest the potential of M344 in anti-latency therapies and an important role for histone modifications and NF-κB transcription factors in regulating HIV-1 LTR gene expression.

  17. Identification and functional analysis of a second RBF-2 binding site within the HIV-1 promoter

    International Nuclear Information System (INIS)

    Dahabieh, Matthew S.; Ooms, Marcel; Malcolm, Tom; Simon, Viviana; Sadowski, Ivan

    2011-01-01

    Transcription from the HIV-1 long terminal repeat (LTR) is mediated by numerous host transcription factors. In this study we characterized an E-box motif (RBE1) within the core promoter that was previously implicated in both transcriptional activation and repression. We show that RBE1 is a binding site for the RBF-2 transcription factor complex (USF1, USF2, and TFII-I), previously shown to bind an upstream viral element, RBE3. The RBE1 and RBE3 elements formed complexes of identical mobility and protein constituents in gel shift assays, both with Jurkat T-cell nuclear extracts and recombinant USF/TFII-I. Furthermore, both elements are regulators of HIV-1 expression; mutations in LTR-luciferase reporters and in HIV-1 molecular clones resulted in decreased transcription, virion production, and proviral expression in infected cells. Collectively, our data indicate that RBE1 is a bona fide RBF-2 binding site and that the RBE1 and RBE3 elements are necessary for mediating proper transcription from the HIV-1 LTR.

  18. Ex vivo response to histone deacetylase (HDAC inhibitors of the HIV long terminal repeat (LTR derived from HIV-infected patients on antiretroviral therapy.

    Directory of Open Access Journals (Sweden)

    Hao K Lu

    Full Text Available Histone deacetylase inhibitors (HDACi can induce human immunodeficiency virus (HIV transcription from the HIV long terminal repeat (LTR. However, ex vivo and in vivo responses to HDACi are variable and the activity of HDACi in cells other than T-cells have not been well characterised. Here, we developed a novel assay to determine the activity of HDACi on patient-derived HIV LTRs in different cell types. HIV LTRs from integrated virus were amplified using triple-nested Alu-PCR from total memory CD4+ T-cells (CD45RO+ isolated from HIV-infected patients prior to and following suppressive antiretroviral therapy. NL4-3 or patient-derived HIV LTRs were cloned into the chromatin forming episomal vector pCEP4, and the effect of HDACi investigated in the astrocyte and epithelial cell lines SVG and HeLa, respectively. There were no significant differences in the sequence of the HIV LTRs isolated from CD4+ T-cells prior to and after 18 months of combination antiretroviral therapy (cART. We found that in both cell lines, the HDACi panobinostat, trichostatin A, vorinostat and entinostat activated patient-derived HIV LTRs to similar levels seen with NL4-3 and all patient derived isolates had similar sensitivity to maximum HDACi stimulation. We observed a marked difference in the maximum fold induction of luciferase by HDACi in HeLa and SVG, suggesting that the effect of HDACi may be influenced by the cellular environment. Finally, we observed significant synergy in activation of the LTR with vorinostat and the viral protein Tat. Together, our results suggest that the LTR sequence of integrated virus is not a major determinant of a functional response to an HDACi.

  19. Hyperthermia stimulates HIV-1 replication.

    Directory of Open Access Journals (Sweden)

    Ferdinand Roesch

    Full Text Available HIV-infected individuals may experience fever episodes. Fever is an elevation of the body temperature accompanied by inflammation. It is usually beneficial for the host through enhancement of immunological defenses. In cultures, transient non-physiological heat shock (42-45°C and Heat Shock Proteins (HSPs modulate HIV-1 replication, through poorly defined mechanisms. The effect of physiological hyperthermia (38-40°C on HIV-1 infection has not been extensively investigated. Here, we show that culturing primary CD4+ T lymphocytes and cell lines at a fever-like temperature (39.5°C increased the efficiency of HIV-1 replication by 2 to 7 fold. Hyperthermia did not facilitate viral entry nor reverse transcription, but increased Tat transactivation of the LTR viral promoter. Hyperthermia also boosted HIV-1 reactivation in a model of latently-infected cells. By imaging HIV-1 transcription, we further show that Hsp90 co-localized with actively transcribing provirus, and this phenomenon was enhanced at 39.5°C. The Hsp90 inhibitor 17-AAG abrogated the increase of HIV-1 replication in hyperthermic cells. Altogether, our results indicate that fever may directly stimulate HIV-1 replication, in a process involving Hsp90 and facilitation of Tat-mediated LTR activity.

  20. HIV-1, HTLV-I and the interleukin-2 receptor: insights into transcriptional control.

    Science.gov (United States)

    Böhnlein, E; Lowenthal, J W; Wano, Y; Franza, B R; Ballard, D W; Greene, W C

    1989-01-01

    In this study, we present direct evidence for the binding of the inducible cellular protein, HIVEN86A, to a 12-bp element present in the IL-2R alpha promoter. This element shares significant sequence similarity with the NF-kappa B binding sites present in the HIV-1 and kappa immunoglobulin enhancers. Transient transfection studies indicate that this kappa B element is both necessary and sufficient to confer tax or mitogen inducibility to a heterologous promoter. As summarized schematically in Fig. 5, the findings suggest that the HIVEN86A protein may play a central role in the activation of cellular genes required for T-cell growth, specifically the IL-2R alpha gene. In addition, the induced HIVEN86A protein also binds to a similar sequence present in the HIV-1 LTR leading to enhanced viral gene expression and ultimately T-cell death. Thus, mitogen activation of the HIV-1 LTR appears to involve the same inducible transcription factor(s) that normally regulates IL-2R alpha gene expression and T-cell growth. These findings further underscore the importance of the state of T-cell activation in the regulation of HIV-1 replication. Our results also demonstrate that HIVEN86A is induced by the tax protein of HTLV-I. Thus, in HTLV-I infected cells, normally the tight control of the transient expression of the IL-2R alpha gene is lost. The constitutive high-level display of IL-2 receptors may play a role in leukemic transformation mediated by HTLV-I (ATL). Apparently by the same mechanism, the tax protein also activates the HIV-1 LTR through the induction of HIVEN86A.(ABSTRACT TRUNCATED AT 250 WORDS)

  1. Structure and possible function of a G-quadruplex in the long terminal repeat of the proviral HIV-1 genome.

    Science.gov (United States)

    De Nicola, Beatrice; Lech, Christopher J; Heddi, Brahim; Regmi, Sagar; Frasson, Ilaria; Perrone, Rosalba; Richter, Sara N; Phan, Anh Tuân

    2016-07-27

    The long terminal repeat (LTR) of the proviral human immunodeficiency virus (HIV)-1 genome is integral to virus transcription and host cell infection. The guanine-rich U3 region within the LTR promoter, previously shown to form G-quadruplex structures, represents an attractive target to inhibit HIV transcription and replication. In this work, we report the structure of a biologically relevant G-quadruplex within the LTR promoter region of HIV-1. The guanine-rich sequence designated LTR-IV forms a well-defined structure in physiological cationic solution. The nuclear magnetic resonance (NMR) structure of this sequence reveals a parallel-stranded G-quadruplex containing a single-nucleotide thymine bulge, which participates in a conserved stacking interaction with a neighboring single-nucleotide adenine loop. Transcription analysis in a HIV-1 replication competent cell indicates that the LTR-IV region may act as a modulator of G-quadruplex formation in the LTR promoter. Consequently, the LTR-IV G-quadruplex structure presented within this work could represent a valuable target for the design of HIV therapeutics. © The Author(s) 2016. Published by Oxford University Press on behalf of Nucleic Acids Research.

  2. Eliminating HIV-1 Packaging Sequences from Lentiviral Vector Proviruses Enhances Safety and Expedites Gene Transfer for Gene Therapy.

    Science.gov (United States)

    Vink, Conrad A; Counsell, John R; Perocheau, Dany P; Karda, Rajvinder; Buckley, Suzanne M K; Brugman, Martijn H; Galla, Melanie; Schambach, Axel; McKay, Tristan R; Waddington, Simon N; Howe, Steven J

    2017-08-02

    Lentiviral vector genomic RNA requires sequences that partially overlap wild-type HIV-1 gag and env genes for packaging into vector particles. These HIV-1 packaging sequences constitute 19.6% of the wild-type HIV-1 genome and contain functional cis elements that potentially compromise clinical safety. Here, we describe the development of a novel lentiviral vector (LTR1) with a unique genomic structure designed to prevent transfer of HIV-1 packaging sequences to patient cells, thus reducing the total HIV-1 content to just 4.8% of the wild-type genome. This has been achieved by reconfiguring the vector to mediate reverse-transcription with a single strand transfer, instead of the usual two, and in which HIV-1 packaging sequences are not copied. We show that LTR1 vectors offer improved safety in their resistance to remobilization in HIV-1 particles and reduced frequency of splicing into human genes. Following intravenous luciferase vector administration to neonatal mice, LTR1 sustained a higher level of liver transgene expression than an equivalent dose of a standard lentivirus. LTR1 vectors produce reverse-transcription products earlier and start to express transgenes significantly quicker than standard lentiviruses after transduction. Finally, we show that LTR1 is an effective lentiviral gene therapy vector as demonstrated by correction of a mouse hemophilia B model. Copyright © 2017 The Author(s). Published by Elsevier Inc. All rights reserved.

  3. LTR real-time PCR for HIV-1 DNA quantitation in blood cells for early diagnosis in infants born to seropositive mothers treated in HAART area (ANRS CO 01).

    Science.gov (United States)

    Avettand-Fènoël, Véronique; Chaix, Marie-Laure; Blanche, Stéphane; Burgard, Marianne; Floch, Corinne; Toure, Kadidia; Allemon, Marie-Christine; Warszawski, Josiane; Rouzioux, Christine

    2009-02-01

    HIV-1 diagnosis in babies born to seropositive mothers is one of the challenges of HIV epidemics in children. A simple, rapid protocol was developed for quantifying HIV-1 DNA in whole blood samples and was used in the ANRS French pediatric cohort in conditions of prevention of mother-to-child transmission. A quantitative HIV-1 DNA protocol (LTR real-time PCR) requiring small blood volumes was developed. First, analytical reproducibility was evaluated on 172 samples. Results obtained on blood cell pellets and Ficoll-Hypaque separated mononuclear cells were compared in 48 adult HIV-1 samples. Second, the protocol was applied to HIV-1 diagnosis in infants in parallel with plasma HIV-RNA quantitation. This prospective study was performed in children born between May 2005 and April 2007 included in the ANRS cohort. The assay showed good reproducibility. The 95% detection cut-off value was 6 copies/PCR, that is, 40 copies/10(6) leukocytes. HIV-DNA levels in whole blood were highly correlated with those obtained after Ficoll-Hypaque separation (r = 0.900, P mothers have received HAART. (c) 2008 Wiley-Liss, Inc.

  4. Overexpression of octamer transcription factors 1 or 2 alone has no effect on HIV-1 transcription in primary human CD4 T cells

    International Nuclear Information System (INIS)

    Zhang Mingce; Genin, Anna; Cron, Randy Q.

    2004-01-01

    We explored the binding of octamer (Oct) transcription factors to the HIV-1 long terminal repeat (LTR) by gel shift assays and showed none of the previously identified four potential Oct binding sites bound Oct-1 or Oct-2. Overexpression of Oct-1 or Oct-2 had no effect on HIV-1 LTR activity in transiently transfected primary human CD4 T cells. Next, primary human CD4 T cells were co-transfected with a green fluorescent protein (GFP)-expression vector and an Oct-1 or Oct-2 expression plasmid. The transfected cells were stimulated for 2 days and then infected with the NL4-3 strain of HIV-1. After 3 days of infection, there were no differences in HIV-1 p24 supernatant levels. Apoptosis of infected or bystander cells overexpressing Oct-1 or Oct-2 compared to control was also unaffected. Our studies demonstrate that Oct-1 and Oct-2 fail to bind to the HIV-1 LTR and have no effect on HIV-1 transcription in primary human CD4 T cells

  5. SUN2 Modulates HIV-1 Infection and Latency through Association with Lamin A/C To Maintain the Repressive Chromatin.

    Science.gov (United States)

    Sun, Wei-Wei; Jiao, Shi; Sun, Li; Zhou, Zhaocai; Jin, Xia; Wang, Jian-Hua

    2018-05-01

    The postintegrational latency of HIV-1 is characterized by reversible silencing of long terminal repeat (LTR)-driven transcription of the HIV genome. It is known that the formation of repressive chromatin at the 5'-LTR of HIV-1 proviral DNA impedes viral transcription by blocking the recruitment of positive transcription factors. How the repressive chromatin is formed and modulated during HIV-1 infection remains elusive. Elucidation of which chromatin reassembly factor mediates the reorganization of chromatin is likely to facilitate the understanding of the host's modulation of HIV-1 transcription and latency. Here we revealed that "Sad1 and UNC84 domain containing 2" (SUN2), an inner nuclear membrane protein, maintained the repressive chromatin and inhibited HIV LTR-driven transcription of proviral DNA through an association with lamin A/C. Specifically, lamin A/C tethered SUN2 to the nucleosomes 1 and 2 of the HIV-1 5'-LTR to block the initiation and elongation of HIV-1 transcription. SUN2 knockdown converted chromatin to an active form and thus enhanced the phosphorylation of RNA polymerase II and its recruitment to the 5'-LTR HIV-1 proviral DNA, leading to reactivation of HIV-1 from latency. Conversely, the exogenous factors such as tumor necrosis factor alpha (TNF-α) induced reactivation, and the replication of HIV-1 led to the disassociation between SUN2 and lamin A/C, suggesting that disruption of the association between SUN2 and lamin A/C to convert the repressive chromatin to the active form might be a prerequisite for the initiation of HIV-1 transcription and replication. Together, our findings indicate that SUN2 is a novel chromatin reassembly factor that helps to maintain chromatin in a repressive state and consequently inhibits HIV-1 transcription. IMPORTANCE Despite the successful use of scores of antiretroviral drugs, HIV latency poses a major impediment to virus eradication. Elucidation of the mechanism of latency facilitates the discovery of new

  6. Novel 3′-Processing Integrase Activity Assay by Real-Time PCR for Screening and Identification of HIV-1 Integrase Inhibitors

    Directory of Open Access Journals (Sweden)

    Supachai Sakkhachornphop

    2015-01-01

    Full Text Available The 3′-end processing (3′P of each viral long terminal repeat (LTR during human immunodeficiency virus type-1 (HIV-1 integration is a vital step in the HIV life cycle. Blocking the 3′P using 3′P inhibitor has recently become an attractive strategy for HIV-1 therapeutic intervention. Recently, we have developed a novel real-time PCR based assay for the detection of 3′P activity in vitro. The methodology usually involves biotinylated HIV-1 LTR, HIV-1 integrase (IN, and specific primers and probe. In this novel assay, we designed the HIV-1 LTR substrate based on a sequence with a homology to HIV-1 LTR labeled at its 3′ end with biotin on the sense strand. Two nucleotides at the 3′ end were subsequently removed by IN activity. Only two nucleotides labeled biotin were captured on an avidin-coated tube; therefore, inhibiting the binding of primers and probe results in late signals in the real-time PCR. This novel assay has successfully detected both the 3′P activity of HIV-1 IN and the anti-IN activity by Raltegravir and sodium azide agent. This real-time PCR assay has been shown to be effective and inexpensive for a high-throughput screening of novel IN inhibitors.

  7. HIV-1 Promoter Single Nucleotide Polymorphisms Are Associated with Clinical Disease Severity.

    Directory of Open Access Journals (Sweden)

    Michael R Nonnemacher

    Full Text Available The large majority of human immunodeficiency virus type 1 (HIV-1 markers of disease progression/severity previously identified have been associated with alterations in host genetic and immune responses, with few studies focused on viral genetic markers correlate with changes in disease severity. This study presents a cross-sectional/longitudinal study of HIV-1 single nucleotide polymorphisms (SNPs contained within the viral promoter or long terminal repeat (LTR in patients within the Drexel Medicine CNS AIDS Research and Eradication Study (CARES Cohort. HIV-1 LTR SNPs were found to associate with the classical clinical disease parameters CD4+ T-cell count and log viral load. They were found in both defined and undefined transcription factor binding sites of the LTR. A novel SNP identified at position 108 in a known COUP (chicken ovalbumin upstream promoter/AP1 transcription factor binding site was significantly correlated with binding phenotypes that are potentially the underlying cause of the associated clinical outcome (increase in viral load and decrease in CD4+ T-cell count.

  8. Plectin regulates the signaling and trafficking of the HIV-1 co-receptor CXCR4 and plays a role in HIV-1 infection

    International Nuclear Information System (INIS)

    Ding Yun; Zhang Li; Goodwin, J. Shawn; Wang Ziqing; Liu Bingdong; Zhang Jingwu; Fan Guohuang

    2008-01-01

    The CXC chemokine CXCL12 and its cognate receptor CXCR4 play an important role in inflammation, human immunodeficiency virus (HIV) infection and cancer metastasis. The signal transduction and intracellular trafficking of CXCR4 are involved in these functions, but the underlying mechanisms remain incompletely understood. In the present study, we demonstrated that the CXCR4 formed a complex with the cytolinker protein plectin in a ligand-dependent manner in HEK293 cells stably expressing CXCR4. The glutathione-S-transferase (GST)-CXCR4 C-terminal fusion proteins co-precipitated with the full-length and the N-terminal fragments of plectin isoform 1 but not with the N-terminal deletion mutants of plectin isoform 1, thereby suggesting an interaction between the N-terminus of plectin and the C-terminus of CXCR4. This interaction was confirmed by confocal microscopic reconstructions showing co-distribution of these two proteins in the internal vesicles after ligand-induced internalization of CXCR4 in HEK293 cells stably expressing CXCR4. Knockdown of plectin with RNA interference (RNAi) significantly inhibited ligand-dependent CXCR4 internalization and attenuated CXCR4-mediated intracellular calcium mobilization and activation of extracellular signal regulated kinase 1/2 (ERK1/2). CXCL12-induced chemotaxis of HEK293 cells stably expressing CXCR4 and of Jurkat T cells was inhibited by the plectin RNAi. Moreover, CXCR4 tropic HIV-1 infection in MAGI (HeLa-CD4-LTR-Gal) cells was inhibited by the RNAi of plectin. Thus, plectin appears to interact with CXCR4 and plays an important role in CXCR4 signaling and trafficking and HIV-1 infection

  9. Involvement of histone methyltransferase GLP in HIV-1 latency through catalysis of H3K9 dimethylation

    International Nuclear Information System (INIS)

    Ding, Donglin; Qu, Xiying; Li, Lin; Zhou, Xin; Liu, Sijie; Lin, Shiguan; Wang, Pengfei; Liu, Shaohui; Kong, Chuijin; Wang, Xiaohui; Liu, Lin; Zhu, Huanzhang

    2013-01-01

    Understanding the mechanism of HIV-1 latency is crucial to eradication of the viral reservoir in HIV-1-infected individuals. However, the role of histone methyltransferase (HMT) G9a-like protein (GLP) in HIV-1 latency is still unclear. In the present work, we established four clonal cell lines containing HIV-1 vector. We found that the integration sites of most clonal cell lines favored active gene regions. However, we also observed hypomethylation of CpG of HIV 5′LTR in all four clonal cell lines. Additionally, 5′-deoxy-5′-methylthioadenosine (MTA), a broad-spectrum histone methyltransferase inhibitor, was used to examine the role of histone methylation in HIV-1 latency. MTA was found to decrease the level of H3K9 dimethylation, causing reactivation of latent HIV-1 in C11 cells. GLP knockdown by small interfering RNA clearly induced HIV-1 LTR expression. Results suggest that GLP may play a significant role in the maintenance of HIV-1 latency by catalyzing dimethylation of H3K9. - Highlights: ► We have established an in vitro model of HIV-1 latency. ► The integration sites of most clonal cell lines favor in active gene regions. ► Hypomethylation occurs in CpG islands of HIV 5′LTR in all four clonal cell lines. ► MTA can reactivate latent HIV-1 by decreasing the level of H3K9 me2 in C11 cells. ► HMT GLP may play a significant role in the maintenance of HIV-1 latency

  10. Regulation of FeLV-945 by c-Myb binding and CBP recruitment to the LTR

    Directory of Open Access Journals (Sweden)

    Finstad Samantha L

    2004-09-01

    Full Text Available Abstract Background Feline leukemia virus (FeLV induces degenerative, proliferative and malignant hematologic disorders in its natural host, the domestic cat. FeLV-945 is a viral variant identified as predominant in a cohort of naturally infected animals. FeLV-945 contains a unique sequence motif in the long terminal repeat (LTR comprised of a single copy of transcriptional enhancer followed by a 21-bp sequence triplicated in tandem. The LTR is precisely conserved among independent cases of multicentric lymphoma, myeloproliferative disease and anemia in animals from the cohort. The 21-bp triplication was previously shown to act as a transcriptional enhancer preferentially in hematopoietic cells and to confer a replicative advantage. The objective of the present study was to examine the molecular mechanism by which the 21-bp triplication exerts its influence and the selective advantage responsible for its precise conservation. Results Potential binding sites for the transcription factor, c-Myb, were identified across the repeat junctions of the 21-bp triplication. Such sites would not occur in the absence of the repeat; thus, a requirement for c-Myb binding to the repeat junctions of the triplication would exert a selective pressure to conserve its sequence precisely. Electrophoretic mobility shift assays demonstrated specific binding of c-Myb to the 21-bp triplication. Reporter gene assays showed that the triplication-containing LTR is responsive to c-Myb, and that responsiveness requires the presence of both c-Myb binding sites. Results further indicated that c-Myb in complex with the 21-bp triplication recruits the transcriptional co-activator, CBP, a regulator of normal hematopoiesis. FeLV-945 replication was shown to be positively regulated by CBP in a manner dependent on the presence of the 21-bp triplication. Conclusion Binding sites for c-Myb across the repeat junctions of the 21-bp triplication may account for its precise conservation in

  11. N-terminally truncated POM121C inhibits HIV-1 replication.

    Directory of Open Access Journals (Sweden)

    Hideki Saito

    Full Text Available Recent studies have identified host cell factors that regulate early stages of HIV-1 infection including viral cDNA synthesis and orientation of the HIV-1 capsid (CA core toward the nuclear envelope, but it remains unclear how viral DNA is imported through the nuclear pore and guided to the host chromosomal DNA. Here, we demonstrate that N-terminally truncated POM121C, a component of the nuclear pore complex, blocks HIV-1 infection. This truncated protein is predominantly localized in the cytoplasm, does not bind to CA, does not affect viral cDNA synthesis, reduces the formation of 2-LTR and diminished the amount of integrated proviral DNA. Studies with an HIV-1-murine leukemia virus (MLV chimeric virus carrying the MLV-derived Gag revealed that Gag is a determinant of this inhibition. Intriguingly, mutational studies have revealed that the blockade by N-terminally-truncated POM121C is closely linked to its binding to importin-β/karyopherin subunit beta 1 (KPNB1. These results indicate that N-terminally-truncated POM121C inhibits HIV-1 infection after completion of reverse transcription and before integration, and suggest an important role for KPNB1 in HIV-1 replication.

  12. Engineering HIV-1-resistant T-cells from short-hairpin RNA-expressing hematopoietic stem/progenitor cells in humanized BLT mice.

    Directory of Open Access Journals (Sweden)

    Gene-Errol E Ringpis

    Full Text Available Down-regulation of the HIV-1 coreceptor CCR5 holds significant potential for long-term protection against HIV-1 in patients. Using the humanized bone marrow/liver/thymus (hu-BLT mouse model which allows investigation of human hematopoietic stem/progenitor cell (HSPC transplant and immune system reconstitution as well as HIV-1 infection, we previously demonstrated stable inhibition of CCR5 expression in systemic lymphoid tissues via transplantation of HSPCs genetically modified by lentiviral vector transduction to express short hairpin RNA (shRNA. However, CCR5 down-regulation will not be effective against existing CXCR4-tropic HIV-1 and emergence of resistant viral strains. As such, combination approaches targeting additional steps in the virus lifecycle are required. We screened a panel of previously published shRNAs targeting highly conserved regions and identified a potent shRNA targeting the R-region of the HIV-1 long terminal repeat (LTR. Here, we report that human CD4(+ T-cells derived from transplanted HSPC engineered to co-express shRNAs targeting CCR5 and HIV-1 LTR are resistant to CCR5- and CXCR4- tropic HIV-1-mediated depletion in vivo. Transduction with the combination vector suppressed CXCR4- and CCR5- tropic viral replication in cell lines and peripheral blood mononuclear cells in vitro. No obvious cytotoxicity or interferon response was observed. Transplantation of combination vector-transduced HSPC into hu-BLT mice resulted in efficient engraftment and subsequent stable gene marking and CCR5 down-regulation in human CD4(+ T-cells within peripheral blood and systemic lymphoid tissues, including gut-associated lymphoid tissue, a major site of robust viral replication, for over twelve weeks. CXCR4- and CCR5- tropic HIV-1 infection was effectively inhibited in hu-BLT mouse spleen-derived human CD4(+ T-cells ex vivo. Furthermore, levels of gene-marked CD4(+ T-cells in peripheral blood increased despite systemic infection with either

  13. Characterization of EIAV LTR variability and compartmentalization in various reservoir tissues of long-term inapparent carrier ponies

    International Nuclear Information System (INIS)

    Reis, Jenner K.P.; Craigo, Jodi K.; Cook, Sheila J.; Issel, Charles J.; Montelaro, Ronald C.

    2003-01-01

    Dynamic genomic variation resulting in changes in envelope antigenicity has been established as a fundamental mechanism of persistence by equine infectious anemia virus (EIAV), as observed with other lentiviruses, including HIV-1. In addition to the reported changes in envelope sequences, however, certain studies indicate the viral LTR as a second variable EIAV gene, with the enhancer region being designated as hypervariable. These observations have lead to the suggestion that LTR variation may alter viral replication properties to optimize to the microenvironment of particular tissue reservoirs. To test this hypothesis directly, we examined the population of LTR quasispecies contained in various tissues of two inapparent carrier ponies experimentally infected with a reference EIAV biological clone for 18 months. The results of these studies demonstrated that the EIAV LTR is in fact highly conserved with respect to the infecting LTR species after 1.5 years of persistent infection and regardless of the tissue reservoir. Thus, these comprehensive analyses demonstrate for the first time that the EIAV LTR is highly conserved during long-term persistent infection and that the observed variations in viral LTR are associated more with in vitro adaptation to replication in cultured cells rather than in vivo replication in natural target cells

  14. NFAT5 regulates HIV-1 in primary monocytes via a highly conserved long terminal repeat site.

    Directory of Open Access Journals (Sweden)

    Shahin Ranjbar

    2006-12-01

    Full Text Available To replicate, HIV-1 capitalizes on endogenous cellular activation pathways resulting in recruitment of key host transcription factors to its viral enhancer. RNA interference has been a powerful tool for blocking key checkpoints in HIV-1 entry into cells. Here we apply RNA interference to HIV-1 transcription in primary macrophages, a major reservoir of the virus, and specifically target the transcription factor NFAT5 (nuclear factor of activated T cells 5, which is the most evolutionarily divergent NFAT protein. By molecularly cloning and sequencing isolates from multiple viral subtypes, and performing DNase I footprinting, electrophoretic mobility shift, and promoter mutagenesis transfection assays, we demonstrate that NFAT5 functionally interacts with a specific enhancer binding site conserved in HIV-1, HIV-2, and multiple simian immunodeficiency viruses. Using small interfering RNA to ablate expression of endogenous NFAT5 protein, we show that the replication of three major HIV-1 viral subtypes (B, C, and E is dependent upon NFAT5 in human primary differentiated macrophages. Our results define a novel host factor-viral enhancer interaction that reveals a new regulatory role for NFAT5 and defines a functional DNA motif conserved across HIV-1 subtypes and representative simian immunodeficiency viruses. Inhibition of the NFAT5-LTR interaction may thus present a novel therapeutic target to suppress HIV-1 replication and progression of AIDS.

  15. CpG methylation controls reactivation of HIV from latency.

    Directory of Open Access Journals (Sweden)

    Jana Blazkova

    2009-08-01

    Full Text Available DNA methylation of retroviral promoters and enhancers localized in the provirus 5' long terminal repeat (LTR is considered to be a mechanism of transcriptional suppression that allows retroviruses to evade host immune responses and antiretroviral drugs. However, the role of DNA methylation in the control of HIV-1 latency has never been unambiguously demonstrated, in contrast to the apparent importance of transcriptional interference and chromatin structure, and has never been studied in HIV-1-infected patients. Here, we show in an in vitro model of reactivable latency and in a latent reservoir of HIV-1-infected patients that CpG methylation of the HIV-1 5' LTR is an additional epigenetic restriction mechanism, which controls resistance of latent HIV-1 to reactivation signals and thus determines the stability of the HIV-1 latency. CpG methylation acts as a late event during establishment of HIV-1 latency and is not required for the initial provirus silencing. Indeed, the latent reservoir of some aviremic patients contained high proportions of the non-methylated 5' LTR. The latency controlled solely by transcriptional interference and by chromatin-dependent mechanisms in the absence of significant promoter DNA methylation tends to be leaky and easily reactivable. In the latent reservoir of HIV-1-infected individuals without detectable plasma viremia, we found HIV-1 promoters and enhancers to be hypermethylated and resistant to reactivation, as opposed to the hypomethylated 5' LTR in viremic patients. However, even dense methylation of the HIV-1 5'LTR did not confer complete resistance to reactivation of latent HIV-1 with some histone deacetylase inhibitors, protein kinase C agonists, TNF-alpha, and their combinations with 5-aza-2deoxycytidine: the densely methylated HIV-1 promoter was most efficiently reactivated in virtual absence of T cell activation by suberoylanilide hydroxamic acid. Tight but incomplete control of HIV-1 latency by Cp

  16. Human macrophages support persistent transcription from unintegrated HIV-1 DNA

    International Nuclear Information System (INIS)

    Kelly, Jeremy; Beddall, Margaret H.; Yu Dongyang; Iyer, Subashini R.; Marsh, Jon W.; Wu Yuntao

    2008-01-01

    Retroviruses require integration of their RNA genomes for both stability and productive viral replication. In HIV infection of non-dividing, resting CD4 T cells, where integration is greatly impeded, the reverse transcribed HIV DNA has limited biological activity and a short half-life. In metabolically active and proliferating T cells, unintegrated DNA rapidly diminishes with cell division. HIV also infects the non-dividing but metabolically active macrophage population. In an in vitro examination of HIV infection of macrophages, we find that unintegrated viral DNA not only has an unusual stability, but also maintains biological activity. The unintegrated linear DNA, 1-LTR, and 2-LTR circles are stable for at least 30 days. Additionally, there is persistent viral gene transcription, which is selective and skewed towards viral early genes such as nef and tat with highly diminished rev and vif. One viral early gene product Nef was measurably synthesized. We also find that independent of integration, the HIV infection process in macrophages leads to generation of numerous chemokines

  17. Differential expression and interaction of host factors augment HIV-1 gene expression in neonatal mononuclear cells

    International Nuclear Information System (INIS)

    Sundaravaradan, Vasudha; Mehta, Roshni; Harris, David T.; Zack, Jerome A.; Ahmad, Nafees

    2010-01-01

    We have previously shown a higher level of HIV-1 replication and gene expression in neonatal (cord) blood mononuclear cells (CBMC) compared with adult blood cells (PBMC), which could be due to differential expression of host factors. We performed the gene expression profile of CBMC and PBMC and found that 8013 genes were expressed at higher levels in CBMC than PBMC and 8028 genes in PBMC than CBMC, including 1181 and 1414 genes upregulated after HIV-1 infection in CBMC and PBMC, respectively. Several transcription factors (NF-κB, E2F, HAT-1, TFIIE, Cdk9, Cyclin T1), signal transducers (STAT3, STAT5A) and cytokines (IL-1β, IL-6, IL-10) were upregulated in CBMC than PBMC, which are known to influence HIV-1 replication. In addition, a repressor of HIV-1 transcription, YY1, was down regulated in CBMC than PBMC and several matrix metalloproteinase (MMP-7, -12, -14) were significantly upregulated in HIV-1 infected CBMC than PBMC. Furthermore, we show that CBMC nuclear extracts interacted with a higher extent to HIV-1 LTR cis-acting sequences, including NF-κB, NFAT, AP1 and NF-IL6 compared with PBMC nuclear extracts and retroviral based short hairpin RNA (shRNA) for STAT3 and IL-6 down regulated their own and HIV-1 gene expression, signifying that these factors influenced differential HIV-1 gene expression in CBMC than PBMC.

  18. Regulatory elements involved in tax-mediated transactivation of the HTLV-I LTR.

    Science.gov (United States)

    Seeler, J S; Muchardt, C; Podar, M; Gaynor, R B

    1993-10-01

    HTLV-I is the etiologic agent of adult T-cell leukemia. In this study, we investigated the regulatory elements and cellular transcription factors which function in modulating HTLV-I gene expression in response to the viral transactivator protein, tax. Transfection experiments into Jurkat cells of a variety of site-directed mutants in the HTLV-1 LTR indicated that each of the three motifs A, B, and C within the 21-bp repeats, the binding sites for the Ets family of proteins, and the TATA box all influenced the degree of tax-mediated activation. Tax is also able to activate gene expression of other viral and cellular promoters. Tax activation of the IL-2 receptor and the HIV-1 LTR is mediated through NF-kappa B motifs. Interestingly, sequences in the 21-bp repeat B and C motifs contain significant homology with NF-kappa B regulatory elements. We demonstrated that an NF-kappa B binding protein, PRDII-BF1, but not the rel protein, bound to the B and C motifs in the 21-bp repeat. PRDII-BF1 was also able to stimulate activation of HTLV-I gene expression by tax. The role of the Ets proteins on modulating tax activation was also studied. Ets 1 but not Ets 2 was capable of increasing the degree of tax activation of the HTLV-I LTR. These results suggest that tax activates gene expression by either direct or indirect interaction with several cellular transcription factors that bind to the HTLV-I LTR.

  19. [Non-LTR retrotransposons: LINEs and SINEs in plant genome].

    Science.gov (United States)

    Cheng, Xu-Dong; Ling, Hong-Qing

    2006-06-01

    Retrotransposons are one of the drivers of genome evolution. They include LTR (long terminal repeat) retrotransposons, which widespread in Eukaryotagenomes, show structural similarity to retroviruses. Non-LTR retrotransposons were first discovered in animal genomes and then identified as ubiquitous components of nuclear genomes in many species across the plant kingdom. They constitute a large fraction of the repetitive DNA. Non-LTR retrotransposons are divided into LINEs (long interspersed nuclear elements) and SINEs (short interspersed nuclear elements). Transposition of non-LTR retrotransposons is rarely observed in plants indicating that most of them are inactive and/or under regulation of the host genome. Transposition is poorly understood, but experimental evidence from other genetic systems shows that LINEs are able to transpose autonomously while non-autonomous SINEs depend on the reverse transcription machinery of other retrotransposons. Phylogenic analysis shows LINEs are probably the most ancient class of retrotransposons in plant genomes, while the origin of SINEs is unknown. This review sums up the above data and wants to show readers a clear picture of non-LTR retrotransposons.

  20. Excision of HIV-1 proviral DNA by recombinant cell permeable tre-recombinase.

    Directory of Open Access Journals (Sweden)

    Lakshmikanth Mariyanna

    Full Text Available Over the previous years, comprehensive studies on antiretroviral drugs resulted in the successful introduction of highly active antiretroviral therapy (HAART into clinical practice for treatment of HIV/AIDS. However, there is still need for new therapeutic approaches, since HAART cannot eradicate HIV-1 from the infected organism and, unfortunately, can be associated with long-term toxicity and the development of drug resistance. In contrast, novel gene therapy strategies may have the potential to reverse the infection by eradicating HIV-1. For example, expression of long terminal repeat (LTR-specific recombinase (Tre-recombinase has been shown to result in chromosomal excision of proviral DNA and, in consequence, in the eradication of HIV-1 from infected cell cultures. However, the delivery of Tre-recombinase currently depends on the genetic manipulation of target cells, a process that is complicating such therapeutic approaches and, thus, might be undesirable in a clinical setting. In this report we demonstrate that E.coli expressed Tre-recombinases, tagged either with the protein transduction domain (PTD from the HIV-1 Tat trans-activator or the translocation motif (TLM of the Hepatitis B virus PreS2 protein, were able to translocate efficiently into cells and showed significant recombination activity on HIV-1 LTR sequences. Tre activity was observed using episomal and stable integrated reporter constructs in transfected HeLa cells. Furthermore, the TLM-tagged enzyme was able to excise the full-length proviral DNA from chromosomal integration sites of HIV-1-infected HeLa and CEM-SS cells. The presented data confirm Tre-recombinase activity on integrated HIV-1 and provide the basis for the non-genetic transient application of engineered recombinases, which may be a valuable component of future HIV eradication strategies.

  1. Effects of integration and replication on transcription of the HIV-1 long terminal repeat

    NARCIS (Netherlands)

    Jeang, K. T.; Berkhout, B.; Dropulic, B.

    1993-01-01

    The activity of a promoter is influenced by chromosomal and cell cycle/replication context. We analyzed the influences of integration and replication on transcription of the human immunodeficiency virus (HIV)-1 long terminal repeat (LTR). We found that one requirement for Tat trans-activated

  2. Reactivation of latent HIV-1 by new semi-synthetic ingenol esters

    Energy Technology Data Exchange (ETDEWEB)

    Pandeló José, Diego [Departamento de Genética, Instituto de Biologia, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-902 (Brazil); Bartholomeeusen, Koen [Department of Medicine, Microbiology and Immunology, University of California at San Francisco, San Francisco, CA 94143-0703 (United States); Delveccio da Cunha, Rodrigo; Abreu, Celina Monteiro [Departamento de Genética, Instituto de Biologia, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-902 (Brazil); Glinski, Jan [PlantaAnalytica LLC, Danbury, CT 06810 (United States); Barbizan Ferreira da Costa, Thais; Bacchi Rabay, Ana Flávia Mello; Pianowski Filho, Luiz Francisco [Kyolab Laboratories, Valinhos, São Paulo 13273-105 (Brazil); Dudycz, Lech W. [Lex Company Research Laboratories, Shirley 01464, MA (United States); Ranga, Udaykumar [Molecular Biology and Genetics Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Bengaluru 560064 (India); Peterlin, Boris Matija [Department of Medicine, Microbiology and Immunology, University of California at San Francisco, San Francisco, CA 94143-0703 (United States); Pianowski, Luiz Francisco [Kyolab Laboratories, Valinhos, São Paulo 13273-105 (Brazil); Tanuri, Amilcar [Departamento de Genética, Instituto de Biologia, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-902 (Brazil); Aguiar, Renato Santana, E-mail: santana@biologia.ufrj.br [Departamento de Genética, Instituto de Biologia, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-902 (Brazil)

    2014-08-15

    The ability of HIV to establish long-lived latent infection is mainly due to transcriptional silencing of viral genome in resting memory T lymphocytes. Here, we show that new semi-synthetic ingenol esters reactivate latent HIV reservoirs. Amongst the tested compounds, 3-caproyl-ingenol (ING B) was more potent in reactivating latent HIV than known activators such as SAHA, ingenol 3,20-dibenzoate, TNF-α, PMA and HMBA. ING B activated PKC isoforms followed by NF-κB nuclear translocation. As virus reactivation is dependent on intact NF-κB binding sites in the LTR promoter region ING B, we have shown that. ING B was able to reactivate virus transcription in primary HIV-infected resting cells up to 12 fold and up to 25 fold in combination with SAHA. Additionally, ING B promoted up-regulation of P-TEFb subunits CDK9/Cyclin T1. The role of ING B on promoting both transcription initiation and elongation makes this compound a strong candidate for an anti-HIV latency drug combined with suppressive HAART. - Highlights: • 3-caproyl-ingenol (ING B) reactivates latent HIV better than SAHA, ingenol 3,20-dibenzoate, TNF-α, PMA and HMBA. • ING B promotes PKC activation and NF-kB translocation to the nucleus. • ING B activates virus transcription of B and non-B subtypes of HIV-1. • ING B activates HIV transcription in infected primary resting CD4+ T cells. • ING B induces higher levels of P-TEFb components in human primary cells.

  3. Evolutionary genomics revealed interkingdom distribution of Tcn1-like chromodomain-containing Gypsy LTR retrotransposons among fungi and plants

    Directory of Open Access Journals (Sweden)

    Blinov Alexander

    2010-04-01

    Full Text Available Abstract Background Chromodomain-containing Gypsy LTR retrotransposons or chromoviruses are widely distributed among eukaryotes and have been found in plants, fungi and vertebrates. The previous comprehensive survey of chromoviruses from mosses (Bryophyta suggested that genomes of non-seed plants contain the clade which is closely related to the retrotransposons from fungi. The origin, distribution and evolutionary history of this clade remained unclear mainly due to the absence of information concerning the diversity and distribution of LTR retrotransposons in other groups of non-seed plants as well as in fungal genomes. Results In present study we preformed in silico analysis of chromodomain-containing LTR retrotransposons in 25 diverse fungi and a number of plant species including spikemoss Selaginella moellendorffii (Lycopodiophyta coupled with an experimental survey of chromodomain-containing Gypsy LTR retrotransposons from diverse non-seed vascular plants (lycophytes, ferns, and horsetails. Our mining of Gypsy LTR retrotransposons in genomic sequences allowed identification of numerous families which have not been described previously in fungi. Two new well-supported clades, Galahad and Mordred, as well as several other previously unknown lineages of chromodomain-containing Gypsy LTR retrotransposons were described based on the results of PCR-mediated survey of LTR retrotransposon fragments from ferns, horsetails and lycophytes. It appeared that one of the clades, namely Tcn1 clade, was present in basidiomycetes and non-seed plants including mosses (Bryophyta and lycophytes (genus Selaginella. Conclusions The interkingdom distribution is not typical for chromodomain-containing LTR retrotransposons clades which are usually very specific for a particular taxonomic group. Tcn1-like LTR retrotransposons from fungi and non-seed plants demonstrated high similarity to each other which can be explained by strong selective constraints and the

  4. Targeted HIV-1 Latency Reversal Using CRISPR/Cas9-Derived Transcriptional Activator Systems.

    Directory of Open Access Journals (Sweden)

    Julia K Bialek

    Full Text Available CRISPR/Cas9 technology is currently considered the most advanced tool for targeted genome engineering. Its sequence-dependent specificity has been explored for locus-directed transcriptional modulation. Such modulation, in particular transcriptional activation, has been proposed as key approach to overcome silencing of dormant HIV provirus in latently infected cellular reservoirs. Currently available agents for provirus activation, so-called latency reversing agents (LRAs, act indirectly through cellular pathways to induce viral transcription. However, their clinical performance remains suboptimal, possibly because reservoirs have diverse cellular identities and/or proviral DNA is intractable to the induced pathways. We have explored two CRISPR/Cas9-derived activator systems as targeted approaches to induce dormant HIV-1 proviral DNA. These systems recruit multiple transcriptional activation domains to the HIV 5' long terminal repeat (LTR, for which we have identified an optimal target region within the LTR U3 sequence. Using this target region, we demonstrate transcriptional activation of proviral genomes via the synergistic activation mediator complex in various in culture model systems for HIV latency. Observed levels of induction are comparable or indeed higher than treatment with established LRAs. Importantly, activation is complete, leading to production of infective viral particles. Our data demonstrate that CRISPR/Cas9-derived technologies can be applied to counteract HIV latency and may therefore represent promising novel approaches in the quest for HIV elimination.

  5. FoxA1 binding to the MMTV LTR modulates chromatin structure and transcription

    International Nuclear Information System (INIS)

    Holmqvist, Per-Henrik; Belikov, Sergey; Zaret, Kenneth S.; Wrange, Oerjan

    2005-01-01

    Novel binding sites for the forkhead transcription factor family member Forkhead box A (FoxA), previously referred to as Hepatocyte Nuclear Factor 3 (HNF3), were found within the mouse mammary tumor virus long terminal repeat (MMTV LTR). The effect of FoxA1 on MMTV LTR chromatin structure, and expression was evaluated in Xenopus laevis oocytes. Mutagenesis of either of the two main FoxA binding sites showed that the distal site, -232/-221, conferred FoxA1-dependent partial inhibition of glucocorticoid receptor (GR) driven MMTV transcription. The proximal FoxA binding segment consisted of two individual FoxA sites at -57/-46 and -45/-34, respectively, that mediated an increased basal MMTV transcription. FoxA1 binding altered the chromatin structure of both the inactive- and the hormone-activated MMTV LTR. Hydroxyl radical foot printing revealed FoxA1-mediated changes in the nucleosome arrangement. Micrococcal nuclease digestion showed the hormone-dependent sub-nucleosome complex, containing ∼120 bp of DNA, to be expanded by FoxA1 binding to the proximal segment into a larger complex containing ∼200 bp. The potential function of the FoxA1-mediated expression of the MMTV provirus for maintenance of expression in different tissues is discussed

  6. LTR retrotransposons in fungi.

    Directory of Open Access Journals (Sweden)

    Anna Muszewska

    Full Text Available Transposable elements with long terminal direct repeats (LTR TEs are one of the best studied groups of mobile elements. They are ubiquitous elements present in almost all eukaryotic genomes. Their number and state of conservation can be a highlight of genome dynamics. We searched all published fungal genomes for LTR-containing retrotransposons, including both complete, functional elements and remnant copies. We identified a total of over 66,000 elements, all of which belong to the Ty1/Copia or Ty3/Gypsy superfamilies. Most of the detected Gypsy elements represent Chromoviridae, i.e. they carry a chromodomain in the pol ORF. We analyzed our data from a genome-ecology perspective, looking at the abundance of various types of LTR TEs in individual genomes and at the highest-copy element from each genome. The TE content is very variable among the analyzed genomes. Some genomes are very scarce in LTR TEs (8000 elements. The data shows that transposon expansions in fungi usually involve an increase both in the copy number of individual elements and in the number of element types. The majority of the highest-copy TEs from all genomes are Ty3/Gypsy transposons. Phylogenetic analysis of these elements suggests that TE expansions have appeared independently of each other, in distant genomes and at different taxonomical levels. We also analyzed the evolutionary relationships between protein domains encoded by the transposon pol ORF and we found that the protease is the fastest evolving domain whereas reverse transcriptase and RNase H evolve much slower and in correlation with each other.

  7. Persistence of attenuated HIV-1 rev alleles in an epidemiologically linked cohort of long-term survivors infected with nef-deleted virus

    Directory of Open Access Journals (Sweden)

    Wesselingh Steven L

    2007-07-01

    Full Text Available Abstract Background The Sydney blood bank cohort (SBBC of long-term survivors consists of multiple individuals infected with nef-deleted, attenuated strains of human immunodeficiency virus type 1 (HIV-1. Although the cohort members have experienced differing clinical courses and now comprise slow progressors (SP as well as long-term nonprogressors (LTNP, longitudinal analysis of nef/long-terminal repeat (LTR sequences demonstrated convergent nef/LTR sequence evolution in SBBC SP and LTNP. Thus, the in vivo pathogenicity of attenuated HIV-1 strains harboured by SBBC members is dictated by factors other than nef/LTR. Therefore, to determine whether defects in other viral genes contribute to attenuation of these HIV-1 strains, we characterized dominant HIV-1 rev alleles that persisted in 4 SBBC subjects; C18, C64, C98 and D36. Results The ability of Rev derived from D36 and C64 to bind the Rev responsive element (RRE in RNA binding assays was reduced by approximately 90% compared to Rev derived from HIV-1NL4-3, C18 or C98. D36 Rev also had a 50–60% reduction in ability to express Rev-dependent reporter constructs in mammalian cells. In contrast, C64 Rev had only marginally decreased Rev function despite attenuated RRE binding. In D36 and C64, attenuated RRE binding was associated with rare amino acid changes at 3 highly conserved residues; Gln to Pro at position 74 immediately N-terminal to the Rev activation domain, and Val to Leu and Ser to Pro at positions 104 and 106 at the Rev C-terminus, respectively. In D36, reduced Rev function was mapped to an unusual 13 amino acid extension at the Rev C-terminus. Conclusion These findings provide new genetic and mechanistic insights important for Rev function, and suggest that Rev function, not Rev/RRE binding may be rate limiting for HIV-1 replication. In addition, attenuated rev alleles may contribute to viral attenuation and long-term survival of HIV-1 infection in a subset of SBBC members.

  8. Human T-lymphotropic Virus-1/2 detected in drug abused men who have sex with men infected with HIV in Surakarta, Indonesia

    Science.gov (United States)

    Agung Prasetyo, Afiono; Sari, Yulia

    2018-05-01

    Human T-lymphotropic virus types 1 and 2 (HTLV-1/2) share similar routes of transmission with human immunodeficiency virus (HIV), and the HTLV-1/2 co-infection may affect the clinical course of HIV infection. The HIV/HTLV-1/2 co-infection risk higher if the patient performing the high-risk activities. This study evaluated the presentation of HTLV-1 and 2 in HIV-infected men who have sex with men with drug abused history in Surakarta Indonesia. Blood samples collected from HIV-infected men who have sex with men with drug abused history in Surakarta were tested using HTLV-1/2 enzyme-linked immunosorbent assays and confirmed by RT-PCR nested addressed the part of HTLV-1 LTR and HTLV-2 LTR region, respectively. The specificity of the molecular assays was confirmed by sequencing the amplicons. The anti HTLV-1/2 positive rate was 17.4% (8/46). All positive serological samples were confirmed by nested RT-PCR. Of these, three was HTLV-1 positive and five was HTLV-2 positive. Molecular analysis of positive PCR products revealed that all HTLV-1 isolates had a close relationship with HTLV-1 isolated in Japan while all HTLV-2 isolates with that of isolated in the USA. HTLV-1 and HTLV-2 were detected in drug abused men who have sex with men infected with HIV in Surakarta.

  9. Characterization and frequency of a newly identified HIV-1 BF1 intersubtype circulating recombinant form in São Paulo, Brazil

    Directory of Open Access Journals (Sweden)

    Neto Walter

    2010-04-01

    Full Text Available Abstract Background HIV circulating recombinant forms (CRFs play an important role in the global and regional HIV epidemics, particularly in regions where multiple subtypes are circulating. To date, several (>40 CRFs are recognized worldwide with five currently circulating in Brazil. Here, we report the characterization of near full-length genome sequences (NFLG of six phylogenetically related HIV-1 BF1 intersubtype recombinants (five from this study and one from other published sequences representing CRF46_BF1. Methods Initially, we selected 36 samples from 888 adult patients residing in São Paulo who had previously been diagnosed as being infected with subclade F1 based on pol subgenomic fragment sequencing. Proviral DNA integrated in peripheral blood mononuclear cells (PBMC was amplified from the purified genomic DNA of all 36-blood samples by five overlapping PCR fragments followed by direct sequencing. Sequence data were obtained from the five fragments that showed identical genomic structure and phylogenetic trees were constructed and compared with previously published sequences. Genuine subclade F1 sequences and any other sequences that exhibited unique mosaic structures were omitted from further analysis Results Of the 36 samples analyzed, only six sequences, inferred from the pol region as subclade F1, displayed BF1 identical mosaic genomes with a single intersubtype breakpoint identified at the nef-U3 overlap (HXB2 position 9347-9365; LTR region. Five of these isolates formed a rigid cluster in phylogentic trees from different subclade F1 fragment regions, which we can now designate as CRF46_BF1. According to our estimate, the new CRF accounts for 0.56% of the HIV-1 circulating strains in São Paulo. Comparison with previously published sequences revealed an additional five isolates that share an identical mosaic structure with those reported in our study. Despite sharing a similar recombinant structure, only one sequence appeared to

  10. Epigenetic regulation of HIV-1 latency: focus on polycomb group (PcG) proteins.

    Science.gov (United States)

    Khan, Sheraz; Iqbal, Mazhar; Tariq, Muhammad; Baig, Shahid M; Abbas, Wasim

    2018-01-01

    HIV-1 latency allows the virus to persist until reactivation, in a transcriptionally silent form in its cellular reservoirs despite the presence of effective cART. Such viral persistence represents a major barrier to HIV eradication since treatment interruption leads to rebound plasma viremia. Polycomb group (PcG) proteins have recently got a considerable attention in regulating HIV-1 post-integration latency as they are involved in the repression of proviral gene expression through the methylation of histones. This epigenetic regulation plays an important role in the establishment and maintenance of HIV-1 latency. In fact, PcG proteins act in complexes and modulate the epigenetic signatures of integrated HIV-1 promoter. Key role played by PcG proteins in the molecular control of HIV-1 latency has led to hypothesize that PcG proteins may represent a valuable target for future HIV-1 therapy in purging HIV-1 reservoirs. In this regard, various small molecules have been synthesized or explored to specifically block the epigenetic activity of PcG. In this review, we will highlight the possible therapeutic approaches to achieve either a functional or sterilizing cure of HIV-1 infection with special focus on histone methylation by PcG proteins together with current and novel pharmacological approaches to reactivate HIV-1 from latency that could ultimately lead towards a better clearance of viral latent reservoirs.

  11. SUN1 Regulates HIV-1 Nuclear Import in a Manner Dependent on the Interaction between the Viral Capsid and Cellular Cyclophilin A.

    Science.gov (United States)

    Luo, Xinlong; Yang, Wei; Gao, Guangxia

    2018-07-01

    Human immunodeficiency virus type 1 (HIV-1) can infect nondividing cells via passing through the nuclear pore complex. The nuclear membrane-imbedded protein SUN2 was recently reported to be involved in the nuclear import of HIV-1. Whether SUN1, which shares many functional similarities with SUN2, is involved in this process remained to be explored. Here we report that overexpression of SUN1 specifically inhibited infection by HIV-1 but not that by simian immunodeficiency virus (SIV) or murine leukemia virus (MLV). Overexpression of SUN1 did not affect reverse transcription but led to reduced accumulation of the 2-long-terminal-repeat (2-LTR) circular DNA and integrated viral DNA, suggesting a block in the process of nuclear import. HIV-1 CA was mapped as a determinant for viral sensitivity to SUN1. Treatment of SUN1-expressing cells with cyclosporine (CsA) significantly reduced the sensitivity of the virus to SUN1, and an HIV-1 mutant containing CA-G89A, which does not interact with cyclophilin A (CypA), was resistant to SUN1 overexpression. Downregulation of endogenous SUN1 inhibited the nuclear entry of the wild-type virus but not that of the G89A mutant. These results indicate that SUN1 participates in the HIV-1 nuclear entry process in a manner dependent on the interaction of CA with CypA. IMPORTANCE HIV-1 infects both dividing and nondividing cells. The viral preintegration complex (PIC) can enter the nucleus through the nuclear pore complex. It has been well known that the viral protein CA plays an important role in determining the pathways by which the PIC enters the nucleus. In addition, the interaction between CA and the cellular protein CypA has been reported to be important in the selection of nuclear entry pathways, though the underlying mechanisms are not very clear. Here we show that both SUN1 overexpression and downregulation inhibited HIV-1 nuclear entry. CA played an important role in determining the sensitivity of the virus to SUN1: the regulatory

  12. Seroprevalence and molecular epidemiology of HTLV-1 isolates from HIV-1 co-infected women in Feira de Santana, Bahia, Brazil.

    Science.gov (United States)

    de Almeida Rego, Filipe Ferreira; Mota-Miranda, Aline; de Souza Santos, Edson; Galvão-Castro, Bernardo; Alcantara, Luiz Carlos

    2010-12-01

    HTLV-1/HIV-1 co-infection is associated with severe clinical manifestations, marked immunodeficiency, and opportunistic pathogenic infections, as well as risk behavior. Salvador, the capital of the State of Bahia, Brazil, has the highest HTLV-1 prevalence (1.74%) found in Brazil. Few studies exist which describe this co-infection found in Salvador and its surrounding areas, much less investigate how these viruses circulate or assess the relationship between them. To describe the epidemiological and molecular features of HTLV in HIV co-infected women. To investigate the prevalence of HTLV/HIV co-infection in surrounding areas, as well as the molecular epidemiology of HTLV, a cross sectional study was carried out involving 107 women infected with HIV-1 from the STD/HIV/AIDS Reference Center located in the neighboring City of Feira de Santana. Patient samples were submitted to ELISA, and HTLV infection was confirmed using Western Blot and Polymerase Chain Reaction (PCR). Phylogenetic analysis using Neighbor-Joining (NJ) and Maximum Likelihood (ML) was performed on HTLV LTR sequences in order to gain further insights about molecular epidemiology and the origins of this virus in Bahia. Four out of five reactive samples were confirmed to be infected with HTLV-1, and one with HTLV-2. The seroprevalence of HTLV among HIV-1 co-infected women was 4.7%. Phylogenetic analysis of the LTR region from four HTLV-1 sequences showed that all isolates were clustered into the main Latin American group within the Transcontinental subgroup of the Cosmopolitan subtype. The HTLV-2 sequence was classified as the HTLV-2c subtype. It was also observed that four HTLV/HIV-1 co-infected women exhibited risk behavior with two having parenteral exposure, while another two were sex workers. This article describes the characteristics of co-infected patients. This co-infection is known to be severe and further studies should be conducted to confirm the suggestion that HTLV-1 is spreading from

  13. Genetic architecture of HIV-1 genes circulating in north India & their functional implications.

    Science.gov (United States)

    Neogi, Ujjwal; Sood, Vikas; Ronsard, Larence; Singh, Jyotsna; Lata, Sneh; Ramachandran, V G; Das, S; Wanchu, Ajay; Banerjea, Akhil C

    2011-12-01

    This review presents data on genetic and functional analysis of some of the HIV-1 genes derived from HIV-1 infected individuals from north India (Delhi, Punjab and Chandigarh). We found evidence of novel B/C recombinants in HIV-1 LTR region showing relatedness to China/Myanmar with 3 copies of Nfκb sites; B/C/D mosaic genomes for HIV-1 Vpr and novel B/C Tat. We reported appearance of a complex recombinant form CRF_02AG of HIV-1 envelope sequences which is predominantly found in Central/Western Africa. Also one Indian HIV-1 envelope subtype C sequence suggested exclusive CXCR4 co-receptor usage. This extensive recombination, which is observed in about 10 per cent HIV-1 infected individuals in the Vpr genes, resulted in remarkably altered functions when compared with prototype subtype B Vpr. The Vpu C was found to be more potent in causing apoptosis when compared with Vpu B when analyzed for subG1 DNA content. The functional implications of these changes as well as in other genes of HIV-1 are discussed in detail with possible implications for subtype-specific pathogenesis highlighted.

  14. Histone acetyltransferase (HAT) activity of p300 modulates human T lymphotropic virus type 1 p30II-mediated repression of LTR transcriptional activity

    International Nuclear Information System (INIS)

    Michael, Bindhu; Nair, Amrithraj M.; Datta, Antara; Hiraragi, Hajime; Ratner, Lee; Lairmore, Michael D.

    2006-01-01

    Human T-lymphotropic virus type-1 (HTLV-1) is a deltaretrovirus that causes adult T cell leukemia/lymphoma, and is implicated in a variety of lymphocyte-mediated inflammatory disorders. HTLV-1 provirus has regulatory and accessory genes in four pX open reading frames. HTLV-1 pX ORF-II encodes two proteins, p13 II and p30 II , which are incompletely defined in virus replication or pathogenesis. We have demonstrated that pX ORF-II mutations block virus replication in vivo and that ORF-II encoded p30 II , a nuclear-localizing protein that binds with CREB-binding protein (CBP)/p300, represses CREB and Tax responsive element (TRE)-mediated transcription. Herein, we have identified p30 II motifs important for p300 binding and in regulating TRE-mediated transcription in the absence and presence of HTLV-1 provirus. Within amino acids 100-179 of p30 II , a region important for repression of LTR-mediated transcription, we identified a single lysine residue at amino acid 106 (K3) that significantly modulates the ability of p30 II to repress TRE-mediated transcription. Exogenous p300, in a dose-responsive manner, reverses p30 II -dependent repression of TRE-mediated transcription, in the absence or presence of the provirus, In contrast to wild type p300, p300 HAT mutants (defective in histone acetyltransferase activity) only partially rescued p30 II -mediated LTR repression. Deacetylation by histone deacetylase-1 (HDAC-1) enhanced p30 II -mediated LTR repression, while inhibition of deacetylation by trichostatin A decreases p30 II -mediated LTR repression. Collectively, our data indicate that HTLV-1 p30 II modulates viral gene expression in a cooperative manner with p300-mediated acetylation

  15. Knockdown of MAP4 and DNAL1 produces a post-fusion and pre-nuclear translocation impairment in HIV-1 replication

    International Nuclear Information System (INIS)

    Gallo, Daniel E.; Hope, Thomas J.

    2012-01-01

    DNAL1 and MAP4 are both microtubule-associated proteins. These proteins were identified as HIV-1 dependency factors in a screen with wild-type HIV-1. In this study we demonstrate that knockdown using DNAL1 and MAP4 siRNAs and shRNAs inhibits HIV-1 infection regardless of envelope. Using a fusion assay, we show that DNAL1 and MAP4 do not impact fusion. By assaying for late reverse transcripts and 2-LTR circles, we show that DNAL1 and MAP4 inhibit both by approximately 50%. These results demonstrate that DNAL1 and MAP4 impact reverse transcription but not nuclear translocation. DNAL1 and MAP4 knockdown cells do not display cytoskeletal defects. Together these experiments indicate that DNAL1 and MAP4 may exert their functions in the HIV life cycle at reverse transcription, prior to nuclear translocation.

  16. Analysis of plant LTR-retrotransposons at the fine-scale family level reveals individual molecular patterns

    Directory of Open Access Journals (Sweden)

    Domingues Douglas S

    2012-04-01

    Full Text Available Abstract Background Sugarcane is an important crop worldwide for sugar production and increasingly, as a renewable energy source. Modern cultivars have polyploid, large complex genomes, with highly unequal contributions from ancestral genomes. Long Terminal Repeat retrotransposons (LTR-RTs are the single largest components of most plant genomes and can substantially impact the genome in many ways. It is therefore crucial to understand their contribution to the genome and transcriptome, however a detailed study of LTR-RTs in sugarcane has not been previously carried out. Results Sixty complete LTR-RT elements were classified into 35 families within four Copia and three Gypsy lineages. Structurally, within lineages elements were similar, between lineages there were large size differences. FISH analysis resulted in the expected pattern of Gypsy/heterochromatin, Copia/euchromatin, but in two lineages there was localized clustering on some chromosomes. Analysis of related ESTs and RT-PCR showed transcriptional variation between tissues and families. Four distinct patterns were observed in sRNA mapping, the most unusual of which was that of Ale1, with very large numbers of 24nt sRNAs in the coding region. The results presented support the conclusion that distinct small RNA-regulated pathways in sugarcane target the lineages of LTR-RT elements. Conclusions Individual LTR-RT sugarcane families have distinct structures, and transcriptional and regulatory signatures. Our results indicate that in sugarcane individual LTR-RT families have distinct behaviors and can potentially impact the genome in diverse ways. For instance, these transposable elements may affect nearby genes by generating a diverse set of small RNA's that trigger gene silencing mechanisms. There is also some evidence that ancestral genomes contribute significantly different element numbers from particular LTR-RT lineages to the modern sugarcane cultivar genome.

  17. Novel RNA Duplex Locks HIV-1 in a Latent State via Chromatin-mediated Transcriptional Silencing

    Directory of Open Access Journals (Sweden)

    Chantelle Ahlenstiel

    2015-01-01

    Full Text Available Transcriptional gene silencing (TGS of mammalian genes can be induced by short interfering RNA (siRNA targeting promoter regions. We previously reported potent TGS of HIV-1 by siRNA (PromA, which targets tandem NF-κB motifs within the viral 5′LTR. In this study, we screened a siRNA panel with the aim of identifying novel 5′LTR targets, to provide multiplexing potential with enhanced viral silencing and application toward developing alternate therapeutic strategies. Systematic examination identified a novel siRNA target, si143, confirmed to induce TGS as the silencing mechanism. TGS was prolonged with virus suppression >12 days, despite a limited ability to induce post- TGS. Epigenetic changes associated with silencing were suggested by partial reversal by histone deacetylase inhibitors and confirmed by chromatin immunoprecipitation analyses, which showed induction of H3K27me3 and H3K9me3, reduction in H3K9Ac, and recruitment of argonaute-1, all characteristic marks of heterochromatin and TGS. Together, these epigenetic changes mimic those associated with HIV-1 latency. Further, robust resistance to reactivation was observed in the J-Lat 9.2 cell latency model, when transduced with shPromA and/or sh143. These data support si/shRNA-mediated TGS approaches to HIV-1 and provide alternate targets to pursue a functional cure, whereby the viral reservoir is locked in latency following antiretroviral therapy cessation.

  18. Convergent evolution of ribonuclease h in LTR retrotransposons and retroviruses.

    Science.gov (United States)

    Ustyantsev, Kirill; Novikova, Olga; Blinov, Alexander; Smyshlyaev, Georgy

    2015-05-01

    Ty3/Gypsy long terminals repeat (LTR) retrotransposons are structurally and phylogenetically close to retroviruses. Two notable structural differences between these groups of genetic elements are 1) the presence in retroviruses of an additional envelope gene, env, which mediates infection, and 2) a specific dual ribonuclease H (RNH) domain encoded by the retroviral pol gene. However, similar to retroviruses, many Ty3/Gypsy LTR retrotransposons harbor additional env-like genes, promoting concepts of the infective mode of these retrotransposons. Here, we provide a further line of evidence of similarity between retroviruses and some Ty3/Gypsy LTR retrotransposons. We identify that, together with their additional genes, plant Ty3/Gypsy LTR retrotransposons of the Tat group have a second RNH, as do retroviruses. Most importantly, we show that the resulting dual RNHs of Tat LTR retrotransposons and retroviruses emerged independently, providing strong evidence for their convergent evolution. The convergent resemblance of Tat LTR retrotransposons and retroviruses may indicate similar selection pressures acting on these diverse groups of elements and reveal potential evolutionary constraints on their structure. We speculate that dual RNH is required to accelerate retrotransposon evolution through increased rates of strand transfer events and subsequent recombination events. © The Author 2015. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

  19. LTR-retrotransposons-based molecular markers in cultivated ...

    African Journals Online (AJOL)

    GRACE

    2006-07-03

    Jul 3, 2006 ... LTR-retrotransposons represent a standard component of the Gossypium Genome (Zaki and Abdel Ghany,. 2003). The analysis of the molecular existence and distribution of ancient and active LTR-retrotransposons, therefore, provides a comprehensive evaluation of the evolutionary history of Gossypium.

  20. On the role of the second coding exon of the HIV-1 Tat protein in virus replication and MHC class I downregulation

    NARCIS (Netherlands)

    Verhoef, K.; Bauer, M.; Meyerhans, A.; Berkhout, B.

    1998-01-01

    Tat is an essential protein of human immunodeficiency virus type 1 (HIV-1) and activates transcription from the viral long terminal repeat (LTR) promoter. The tat gene is composed of two coding exons of which the first, corresponding to the N-terminal 72 amino acid residues, has been reported to be

  1. Large-scale transcriptome data reveals transcriptional activity of fission yeast LTR retrotransposons

    DEFF Research Database (Denmark)

    Mourier, Tobias; Willerslev, Eske

    2010-01-01

    of transcriptional activity are observed from both strands of solitary LTR sequences. Transcriptome data collected during meiosis suggests that transcription of solitary LTRs is correlated with the transcription of nearby protein-coding genes. CONCLUSIONS: Presumably, the host organism negatively regulates...

  2. Modulation of chromatin structure by the FACT histone chaperone complex regulates HIV-1 integration.

    Science.gov (United States)

    Matysiak, Julien; Lesbats, Paul; Mauro, Eric; Lapaillerie, Delphine; Dupuy, Jean-William; Lopez, Angelica P; Benleulmi, Mohamed Salah; Calmels, Christina; Andreola, Marie-Line; Ruff, Marc; Llano, Manuel; Delelis, Olivier; Lavigne, Marc; Parissi, Vincent

    2017-07-28

    Insertion of retroviral genome DNA occurs in the chromatin of the host cell. This step is modulated by chromatin structure as nucleosomes compaction was shown to prevent HIV-1 integration and chromatin remodeling has been reported to affect integration efficiency. LEDGF/p75-mediated targeting of the integration complex toward RNA polymerase II (polII) transcribed regions ensures optimal access to dynamic regions that are suitable for integration. Consequently, we have investigated the involvement of polII-associated factors in the regulation of HIV-1 integration. Using a pull down approach coupled with mass spectrometry, we have selected the FACT (FAcilitates Chromatin Transcription) complex as a new potential cofactor of HIV-1 integration. FACT is a histone chaperone complex associated with the polII transcription machinery and recently shown to bind LEDGF/p75. We report here that a tripartite complex can be formed between HIV-1 integrase, LEDGF/p75 and FACT in vitro and in cells. Biochemical analyzes show that FACT-dependent nucleosome disassembly promotes HIV-1 integration into chromatinized templates, and generates highly favored nucleosomal structures in vitro. This effect was found to be amplified by LEDGF/p75. Promotion of this FACT-mediated chromatin remodeling in cells both increases chromatin accessibility and stimulates HIV-1 infectivity and integration. Altogether, our data indicate that FACT regulates HIV-1 integration by inducing local nucleosomes dissociation that modulates the functional association between the incoming intasome and the targeted nucleosome.

  3. HIV transcription is induced with some forms of cell killing

    International Nuclear Information System (INIS)

    Woloschak, G.E.; Schreck, S.; Chang-Liu, C.-M.; Libertin, C.R.

    1996-01-01

    Using HeLa cells stably transfected with an HIV-LTR-CAT construct', we demonstrated a peak in CAT induction that occurs in viable (but not necessarily cell-division-competent) cells 24 h following exposure to some cell-killing agents. Γ rays were the only cell-killing agent which did not induce HIV transcription; this can be attributed to the fact that γ-ray-induced apoptotic death requires function p53, which is missing in HeLa cells. For all other agents, HIV-LTR induction was dose-dependent and correlated with the amount of cell killing that occurred in the culture

  4. Long Terminal Repeat Circular DNA as Markers of Active Viral Replication of Human T Lymphotropic Virus-1 in Vivo

    Directory of Open Access Journals (Sweden)

    James M Fox

    2016-03-01

    Full Text Available Clonal expansion of human T-lymphotropic virus type-1 (HTLV-1 infected cells in vivo is well documented. Unlike human immunodeficiency virus type 1 (HIV-1, HTLV-1 plasma RNA is sparse. The contribution of the “mitotic” spread of HTLV-1 compared with infectious spread of the virus to HTLV-1 viral burden in established infection is uncertain. Since extrachromosomal long terminal repeat (LTR DNA circles are indicators of viral replication in HIV-1 carriers with undetectable plasma HIV RNA, we hypothesised that HTLV-1 LTR circles could indicate reverse transcriptase (RT usage and infectious activity. 1LTR and 2LTR DNA circles were measured in HTLV-1 cell lines and peripheral blood mononuclear cells (PBMC of asymptomatic carriers (ACs and patients with HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP or adult T cell leukaemia/lymphoma (ATLL. 1LTR DNA circles were detected in 14/20 patients at a mean of 1.38/100 PBMC but did not differentiate disease status nor correlate with HTLV-1 DNA copies. 2LTR DNA circles were detected in 30/31 patients and at higher concentrations in patients with HTLV-1-associated diseases, independent of HTLV-1 DNA load. In an incident case the 2LTR DNA circle concentration increased 2.1 fold at the onset of HAM/TSP compared to baseline. Detectable and fluctuating levels of HTLV-1 DNA circles in patients indicate viral RT usage and virus replication. Our results indicate HTLV-1 viral replication capacity is maintained in chronic infection and may be associated with disease onset.

  5. The HIV-1 Rev/RRE system is required for HIV-1 5' UTR cis elements to augment encapsidation of heterologous RNA into HIV-1 viral particles

    Directory of Open Access Journals (Sweden)

    Ma Hong

    2011-06-01

    Full Text Available Abstract Background The process of HIV-1 genomic RNA (gRNA encapsidation is governed by a number of viral encoded components, most notably the Gag protein and gRNA cis elements in the canonical packaging signal (ψ. Also implicated in encapsidation are cis determinants in the R, U5, and PBS (primer binding site from the 5' untranslated region (UTR. Although conventionally associated with nuclear export of HIV-1 RNA, there is a burgeoning role for the Rev/RRE in the encapsidation process. Pleiotropic effects exhibited by these cis and trans viral components may confound the ability to examine their independent, and combined, impact on encapsidation of RNA into HIV-1 viral particles in their innate viral context. We systematically reconstructed the HIV-1 packaging system in the context of a heterologous murine leukemia virus (MLV vector RNA to elucidate a mechanism in which the Rev/RRE system is central to achieving efficient and specific encapsidation into HIV-1 viral particles. Results We show for the first time that the Rev/RRE system can augment RNA encapsidation independent of all cis elements from the 5' UTR (R, U5, PBS, and ψ. Incorporation of all the 5' UTR cis elements did not enhance RNA encapsidation in the absence of the Rev/RRE system. In fact, we demonstrate that the Rev/RRE system is required for specific and efficient encapsidation commonly associated with the canonical packaging signal. The mechanism of Rev/RRE-mediated encapsidation is not a general phenomenon, since the combination of the Rev/RRE system and 5' UTR cis elements did not enhance encapsidation into MLV-derived viral particles. Lastly, we show that heterologous MLV RNAs conform to transduction properties commonly associated with HIV-1 viral particles, including in vivo transduction of non-dividing cells (i.e. mouse neurons; however, the cDNA forms are episomes predominantly in the 1-LTR circle form. Conclusions Premised on encapsidation of a heterologous RNA into

  6. A parametric LTR solution for discrete-time systems

    DEFF Research Database (Denmark)

    Niemann, Hans Henrik; Jannerup, Ole Erik

    1989-01-01

    A parametric LTR (loop transfer recovery) solution for discrete-time compensators incorporating filtering observers which achieve exact recovery is presented for both minimum- and non-minimum-phase systems. First the recovery error, which defines the difference between the target loop transfer...... and the full loop transfer function, is manipulated into a general form involving the target loop transfer matrix and the fundamental recovery matrix. A parametric LTR solution based on the recovery matrix is developed. It is shown that the LQR/LTR (linear quadratic Gaussian/loop transfer recovery) solution...

  7. Inhibition of HIV Replication by Cyclic and Hairpin PNAs Targeting the HIV-1 TAR RNA Loop

    Science.gov (United States)

    Upert, Gregory; Di Giorgio, Audrey; Upadhyay, Alok; Manvar, Dinesh; Pandey, Nootan; Pandey, Virendra N.; Patino, Nadia

    2012-01-01

    Human immunodeficiency virus-1 (HIV-1) replication and gene expression entails specific interaction of the viral protein Tat with its transactivation responsive element (TAR), to form a highly stable stem-bulge-loop structure. Previously, we described triphenylphosphonium (TPP) cation-based vectors that efficiently deliver nucleotide analogs (PNAs) into the cytoplasm of cells. In particular, we showed that the TPP conjugate of a linear 16-mer PNA targeting the apical stem-loop region of TAR impedes Tat-mediated transactivation of the HIV-1 LTR in vitro and also in cell culture systems. In this communication, we conjugated TPP to cyclic and hairpin PNAs targeting the loop region of HIV-1 TAR and evaluated their antiviral efficacy in a cell culture system. We found that TPP-cyclic PNAs containing only 8 residues, showed higher antiviral potency compared to hairpin PNAs of 12 or 16 residues. We further noted that the TPP-conjugates of the 8-mer cyclic PNA as well as the 16-mer linear PNA displayed similar antiviral efficacy. However, cyclic PNAs were shown to be highly specific to their target sequences. This communication emphasizes on the importance of small constrained cyclic PNAs over both linear and hairpin structures for targeting biologically relevant RNA hairpins. PMID:23029603

  8. Inhibition of HIV Replication by Cyclic and Hairpin PNAs Targeting the HIV-1 TAR RNA Loop

    Directory of Open Access Journals (Sweden)

    Gregory Upert

    2012-01-01

    Full Text Available Human immunodeficiency virus-1 (HIV-1 replication and gene expression entails specific interaction of the viral protein Tat with its transactivation responsive element (TAR, to form a highly stable stem-bulge-loop structure. Previously, we described triphenylphosphonium (TPP cation-based vectors that efficiently deliver nucleotide analogs (PNAs into the cytoplasm of cells. In particular, we showed that the TPP conjugate of a linear 16-mer PNA targeting the apical stem-loop region of TAR impedes Tat-mediated transactivation of the HIV-1 LTR in vitro and also in cell culture systems. In this communication, we conjugated TPP to cyclic and hairpin PNAs targeting the loop region of HIV-1 TAR and evaluated their antiviral efficacy in a cell culture system. We found that TPP-cyclic PNAs containing only 8 residues, showed higher antiviral potency compared to hairpin PNAs of 12 or 16 residues. We further noted that the TPP-conjugates of the 8-mer cyclic PNA as well as the 16-mer linear PNA displayed similar antiviral efficacy. However, cyclic PNAs were shown to be highly specific to their target sequences. This communication emphasizes on the importance of small constrained cyclic PNAs over both linear and hairpin structures for targeting biologically relevant RNA hairpins.

  9. Analytical Performances of Human Immunodeficiency Virus Type 1 RNA-Based Amplix® Real-Time PCR Platform for HIV-1 RNA Quantification

    Directory of Open Access Journals (Sweden)

    Christian Diamant Mossoro-Kpinde

    2016-01-01

    Full Text Available Objectives. We evaluated the performances of Amplix real-time PCR platform developed by Biosynex (Strasbourg, France, combining automated station extraction (Amplix station 16 Dx and real-time PCR (Amplix NG, for quantifying plasma HIV-1 RNA by lyophilized HIV-1 RNA-based Amplix reagents targeting gag and LTR, using samples from HIV-1-infected adults from Central African Republic. Results. Amplix real-time PCR assay showed low limit of detection (28 copies/mL, across wide dynamic range (1.4–10 log copies/mL, 100% sensitivity and 99% specificity, high reproducibility, and accuracy with mean bias < 5%. The assay showed excellent correlations and concordance of 95.3% with the reference HIV-1 RNA load assay (Roche, with mean absolute bias of +0.097 log copies/mL by Bland-Altman analysis. The assay was able to detect and quantify the most prevalent HIV-1 subtype strains and the majority of non-B subtypes, CRFs of HIV-1 group M, and HIV-1 groups N and O circulating in Central Africa. The Amplix assay showed 100% sensitivity and 99.6% specificity to diagnose virological failure in clinical samples from antiretroviral drug-experienced patients. Conclusions. The HIV-1 RNA-based Amplix real-time PCR platform constitutes sensitive and reliable system for clinical monitoring of HIV-1 RNA load in HIV-1-infected children and adults, particularly adapted to intermediate laboratory facilities in sub-Saharan Africa.

  10. Zinc finger nuclease: a new approach for excising HIV-1 proviral DNA from infected human T cells.

    Science.gov (United States)

    Qu, Xiying; Wang, Pengfei; Ding, Donglin; Wang, Xiaohui; Zhang, Gongmin; Zhou, Xin; Liu, Lin; Zhu, Xiaoli; Zeng, Hanxian; Zhu, Huanzhang

    2014-09-01

    A major reason that Acquired Immune Deficiency Syndrome (AIDS) cannot be completely cured is the human immunodeficiency virus 1 (HIV-1) provirus integrated into the human genome. Though existing therapies can inhibit replication of HIV-1, they cannot eradicate it. A molecular therapy gains popularity due to its specifically targeting to HIV-1 infected cells and effectively removing the HIV-1, regardless of viral genes being active or dormant. Now, we propose a new method which can excellently delete the HIV provirus from the infected human T cell genome. First, we designed zinc-finger nucleases (ZFNs) that target a sequence within the long terminal repeat (LTR) U3 region that is highly conserved in whole clade. Then, we screened out one pair of ZFN and named it as ZFN-U3. We discovered that ZFN-U3 can exactly target and eliminate the full-length HIV-1 proviral DNA after the infected human cell lines treated with it, and the frequency of its excision was about 30 % without cytotoxicity. These results prove that ZFN-U3 can efficiently excise integrated HIV-1 from the human genome in infected cells. This method to delete full length HIV-1 in human genome can therefore provide a novel approach to cure HIV-infected individuals in the future.

  11. An application of LTR design in fault detection

    DEFF Research Database (Denmark)

    Niemann, Hans Henrik

    1998-01-01

    The fault detection and isolation (FDI) problem is considered in this paper. The FDI problem is formulated as a filter design problem, where the faults in the system is estimated and the disturbance acting on the system is rejected. It turns out that the filter design problem can be considered...... as a standard Loop Transfer Recovery (LTR) design problem. As a consequence of the connection between LTR and FDI design, it is shown in an example how the LQG/LTR design method for full order and a proportional-integral observer can be applied with advantages in connection with FDI....

  12. Divergent transcriptional regulation of HIV-1: Structural and Functional Analysis of the LTR Promoter Activity of Group M, N and O

    OpenAIRE

    Somogyi, Sybille

    2010-01-01

    HIV-1 is classified into three distinct genetic groups: M (major), N (non-M; non-O) and O (outlier). Within the group M actually nine subtypes and an increasing number of circulating recombinant forms have been identified. The global spread of subtypes and CRF (circulating recombinant form) differs with respect to geographic regions and the routes of transmission. Besides sociodemographic factors, biological properties of the host and the virus may influence the different prevalences of the s...

  13. HIV-1 matrix dependent membrane targeting is regulated by Gag mRNA trafficking.

    Directory of Open Access Journals (Sweden)

    Jing Jin

    Full Text Available Retroviral Gag polyproteins are necessary and sufficient for virus budding. Productive HIV-1 Gag assembly takes place at the plasma membrane. However, little is known about the mechanisms by which thousands of Gag molecules are targeted to the plasma membrane. Using a bimolecular fluorescence complementation (BiFC assay, we recently reported that the cellular sites and efficiency of HIV-1 Gag assembly depend on the precise pathway of Gag mRNA export from the nucleus, known to be mediated by Rev. Here we describe an assembly deficiency in human cells for HIV Gag whose expression depends on hepatitis B virus (HBV post-transcriptional regulatory element (PRE mediated-mRNA nuclear export. PRE-dependent HIV Gag expressed well in human cells, but assembled with slower kinetics, accumulated intracellularly, and failed to associate with a lipid raft compartment where the wild-type Rev-dependent HIV-1 Gag efficiently assembles. Surprisingly, assembly and budding of PRE-dependent HIV Gag in human cells could be rescued in trans by co-expression of Rev-dependent Gag that provides correct membrane targeting signals, or in cis by replacing HIV matrix (MA with other membrane targeting domains. Taken together, our results demonstrate deficient membrane targeting of PRE-dependent HIV-1 Gag and suggest that HIV MA function is regulated by the trafficking pathway of the encoding mRNA.

  14. LEDGF/p75 Deficiency Increases Deletions at the HIV-1 cDNA Ends.

    Science.gov (United States)

    Bueno, Murilo T D; Reyes, Daniel; Llano, Manuel

    2017-09-15

    Processing of unintegrated linear HIV-1 cDNA by the host DNA repair system results in its degradation and/or circularization. As a consequence, deficient viral cDNA integration generally leads to an increase in the levels of HIV-1 cDNA circles containing one or two long terminal repeats (LTRs). Intriguingly, impaired HIV-1 integration in LEDGF/p75-deficient cells does not result in a correspondent increase in viral cDNA circles. We postulate that increased degradation of unintegrated linear viral cDNA in cells lacking the lens epithelium-derived growth factor (LEDGF/p75) account for this inconsistency. To evaluate this hypothesis, we characterized the nucleotide sequence spanning 2-LTR junctions isolated from LEDGF/p75-deficient and control cells. LEDGF/p75 deficiency resulted in a significant increase in the frequency of 2-LTRs harboring large deletions. Of note, these deletions were dependent on the 3' processing activity of integrase and were not originated by aberrant reverse transcription. Our findings suggest a novel role of LEDGF/p75 in protecting the unintegrated 3' processed linear HIV-1 cDNA from exonucleolytic degradation.

  15. NF90 una proteína celular que se une a RNAds inhibe la transactivación del LTR del HIV-1 mediada por TAT

    Directory of Open Access Journals (Sweden)

    Silvio Urcuqui Inchima

    2001-04-01

    Full Text Available

    La transactivación del LTR de HIV-1 requiere la interacción de la proteína Tat ( trans-activation transcription con la estructura TAR ( trans-activation response, que se encuentra localizada en el extremo 5’ de todos los transcriptos virales. La interacción de la proteína Tat con TAR forma un precomplejo transcripcional indispensable para la eficiente transcripción del genoma viral.
    La interacción de diferentes factores celulares (cdk9 y ciclina T, entre otros con el precomplejo Tat-TAR, constituye un complejo estable que facilita la fosforilación de la subunidad mayor de la RNA polimerasa II, asegurando una eficiente elongación de los transcriptos virales. No se han descripto proteínas capaces de regular negativamente la función de Tat con resultados nefastos para la replicación viral. También se ha descrito otro tipo de proteínas celulares con capacidad de interactuar con TAR. El ejemplo mejor caracterizado es la proteína-kinasa dependiente de RNA (PKR, se autofosforila y mediante fosforilación del factor eIF2, inhibe la síntesis de proteínas. Con el presente trabajo se
    pretendió aislar y caracterizar otras proteínas celulares capaces de interactuar con la estructura TAR y estudiar su efecto en la función de Tat.

     

  16. Anti-HIV-1 activity of anionic polymers: a comparative study of candidate microbicides

    Directory of Open Access Journals (Sweden)

    Li Yun-Yao

    2002-11-01

    Full Text Available Abstract Background Cellulose acetate phthalate (CAP in soluble form blocks coreceptor binding sites on the virus envelope glycoprotein gp120 and elicits gp41 six-helix bundle formation, processes involved in virus inactivation. CAP is not soluble at pH Methods Enzyme linked immunosorbent assays (ELISA were used to (1 study HIV-1 IIIB and BaL binding to micronized CAP; (2 detect virus disintegration; and (3 measure gp41 six-helix bundle formation. Cells containing integrated HIV-1 LTR linked to the β-gal gene and expressing CD4 and coreceptors CXCR4 or CCR5 were used to measure virus infectivity. Results 1 HIV-1 IIIB and BaL, respectively, effectively bound to micronized CAP. 2 The interaction between HIV-1 and micronized CAP led to: (a gp41 six-helix bundle formation; (b virus disintegration and shedding of envelope glycoproteins; and (c rapid loss of infectivity. Polymers other than CAP, except Carbomer 974P, elicited gp41 six-helix bundle formation in HIV-1 IIIB but only poly(napthalene sulfonate, in addition to CAP, had this effect on HIV-1 BaL. These polymers differed with respect to their virucidal activities, the differences being more pronounced for HIV-1 BaL. Conclusions Micronized CAP is the only candidate topical microbicide with the capacity to remove rapidly by adsorption from physiological fluids HIV-1 of both the X4 and R5 biotypes and is likely to prevent virus contact with target cells. The interaction between micronized CAP and HIV-1 leads to rapid virus inactivation. Among other anionic polymers, cellulose sulfate, BufferGel and aryl sulfonates appear most effective in this respect.

  17. A Theory of LTR Junk-food Consumption

    OpenAIRE

    Levy, Amnon

    2003-01-01

    LTR junk-food consumption balances the marginal satisfaction with the marginal deterioration of health. An LTR person discounts the instantaneous marginal satisfaction from junk-food consumption by its implications for his survival probability. His change rate of health evaluation is increased (decreased) by junk-food consumption when health is better (worse) than a critical level. The moderating direct effects of age and relative price on junk-food consumption may be amplified, or dimmed, by...

  18. A new activity of anti-HIV and anti-tumor protein GAP31: DNA adenosine glycosidase - Structural and modeling insight into its functions

    Energy Technology Data Exchange (ETDEWEB)

    Li, Hui-Guang [Department of Biochemistry, New York University School of Medicine, New York, NY 10016 (United States); Huang, Philip L. [American Biosciences, Boston, MA 02114 (United States); Zhang, Dawei; Sun, Yongtao [Department of Biochemistry, New York University School of Medicine, New York, NY 10016 (United States); Chen, Hao-Chia [Endocrinology and Reproduction Research Branch, National Institute of Child Health and Human Development, NIH, Bethesda, MD 20892 (United States); Zhang, John [Department of Chemistry, New York University, New York, NY 10003 (United States); Huang, Paul L. [Department of Medicine, Harvard Medical School and Massachusetts General Hospital, Boston, MA 02114 (United States); Kong, Xiang-Peng, E-mail: xiangpeng.kong@med.nyu.edu [Department of Biochemistry, New York University School of Medicine, New York, NY 10016 (United States); Lee-Huang, Sylvia, E-mail: sylvia.lee-huang@med.nyu.edu [Department of Biochemistry, New York University School of Medicine, New York, NY 10016 (United States)

    2010-01-01

    We report here the high-resolution atomic structures of GAP31 crystallized in the presence of HIV-LTR DNA oligonucleotides systematically designed to examine the adenosine glycosidase activity of this anti-HIV and anti-tumor plant protein. Structural analysis and molecular modeling lead to several novel findings. First, adenine is bound at the active site in the crystal structures of GAP31 to HIV-LTR duplex DNA with 5' overhanging adenosine ends, such as the 3'-processed HIV-LTR DNA but not to DNA duplex with blunt ends. Second, the active site pocket of GAP31 is ideally suited to accommodate the 5' overhanging adenosine of the 3'-processed HIV-LTR DNA and the active site residues are positioned to perform the adenosine glycosidase activity. Third, GAP31 also removes the 5'-end adenine from single-stranded HIV-LTR DNA oligonucleotide as well as any exposed adenosine, including that of single nucleotide dAMP but not from AMP. Fourth, GAP31 does not de-purinate guanosine from di-nucleotide GT. These results suggest that GAP31 has DNA adenosine glycosidase activity against accessible adenosine. This activity is distinct from the generally known RNA N-glycosidase activity toward the 28S rRNA. It may be an alternative function that contributes to the antiviral and anti-tumor activities of GAP31. These results provide molecular insights consistent with the anti-HIV mechanisms of GAP31 in its inhibition on the integration of viral DNA into the host genome by HIV-integrase as well as irreversible topological relaxation of the supercoiled viral DNA.

  19. Regulatory CD4 T cells inhibit HIV-1 expression of other CD4 T cell subsets via interactions with cell surface regulatory proteins.

    Science.gov (United States)

    Zhang, Mingce; Robinson, Tanya O; Duverger, Alexandra; Kutsch, Olaf; Heath, Sonya L; Cron, Randy Q

    2018-03-01

    During chronic HIV-1 infection, regulatory CD4 T cells (Tregs) frequently represent the largest subpopulation of CD4 T cell subsets, implying relative resistant to HIV-1. When HIV-1 infection of CD4 T cells was explored in vitro and ex vivo from patient samples, Tregs possessed lower levels of HIV-1 DNA and RNA in comparison with conventional effector and memory CD4 T cells. Moreover, Tregs suppressed HIV-1 expression in other CD4 T cells in an in vitro co-culture system. This suppression was mediated in part via multiple inhibitory surface proteins expressed on Tregs. Antibody blockade of CTLA-4, PD-1, and GARP on Tregs resulted in increased HIV-1 DNA integration and mRNA expression in neighboring CD4 T cells. Moreover, antibody blockade of Tregs inhibitory proteins resulted in increased HIV-1 LTR transcription in co-cultured CD4 T cells. Thus, Tregs inhibit HIV-1 infection of other CD4 T cell subsets via interactions with inhibitory cell surface proteins. Copyright © 2018 Elsevier Inc. All rights reserved.

  20. Layers of Self- and Co-Regulation: Teachers Working Collaboratively to Support Adolescents' Self-Regulated Learning through Reading

    Directory of Open Access Journals (Sweden)

    Deborah L. Butler

    2013-01-01

    Full Text Available This paper reports findings from a longitudinal project in which secondary teachers were working collaboratively to support adolescents' self-regulated learning through reading (LTR in subject-area classrooms. We build from prior research to “connect the dots” between teachers' engagement in self- and co-regulated inquiry, associated shifts in classroom practice, and student self-regulation. More specifically, we investigated whether and how teachers working within a community of inquiry were mobilizing research to shape classroom practice and advance student learning. Drawing on evidence from 18 teachers and their respective classrooms, we describe findings related to the following research questions: (1 While engaged in self- and co-regulated inquiry, what types of practices did teachers enact to support LTR in their subject-area classrooms? (2 How did teachers draw on research-based resources to inform practice development? (3 What kinds of practices could be associated with gains in students' self-regulated LTR? In our discussion, we highlight contributions to understanding how teachers can be supported to situate research in authentic classroom environments and about qualities of practices supportive of students' self-regulated LTR. We also identify limitations of this work and important future directions.

  1. Integrated and Total HIV-1 DNA Predict Ex Vivo Viral Outgrowth.

    Directory of Open Access Journals (Sweden)

    Maja Kiselinova

    2016-03-01

    Full Text Available The persistence of a reservoir of latently infected CD4 T cells remains one of the major obstacles to cure HIV. Numerous strategies are being explored to eliminate this reservoir. To translate these efforts into clinical trials, there is a strong need for validated biomarkers that can monitor the reservoir over time in vivo. A comprehensive study was designed to evaluate and compare potential HIV-1 reservoir biomarkers. A cohort of 25 patients, treated with suppressive antiretroviral therapy was sampled at three time points, with median of 2.5 years (IQR: 2.4-2.6 between time point 1 and 2; and median of 31 days (IQR: 28-36 between time point 2 and 3. Patients were median of 6 years (IQR: 3-12 on ART, and plasma viral load (<50 copies/ml was suppressed for median of 4 years (IQR: 2-8. Total HIV-1 DNA, unspliced (us and multiply spliced HIV-1 RNA, and 2LTR circles were quantified by digital PCR in peripheral blood, at 3 time points. At the second time point, a viral outgrowth assay (VOA was performed, and integrated HIV-1 DNA and relative mRNA expression levels of HIV-1 restriction factors were quantified. No significant change was found for long- and short-term dynamics of all HIV-1 markers tested in peripheral blood. Integrated HIV-1 DNA was associated with total HIV-1 DNA (p<0.001, R² = 0.85, us HIV-1 RNA (p = 0.029, R² = 0.40, and VOA (p = 0.041, R2 = 0.44. Replication-competent virus was detected in 80% of patients by the VOA and it correlated with total HIV-1 DNA (p = 0.039, R² = 0.54. The mean quantification difference between Alu-PCR and VOA was 2.88 log10, and 2.23 log10 between total HIV-1 DNA and VOA. The levels of usHIV-1 RNA were inversely correlated with mRNA levels of several HIV-1 restriction factors (TRIM5α, SAMHD1, MX2, SLFN11, pSIP1. Our study reveals important correlations between the viral outgrowth and total and integrated HIV-1 DNA measures, suggesting that the total pool of HIV-1 DNA may predict the size of the

  2. LTR retrotransposon landscape in Medicago truncatula: more rapid removal than in rice

    Directory of Open Access Journals (Sweden)

    Liu Jin-Song

    2008-08-01

    Full Text Available Abstract Background Long terminal repeat retrotransposons (LTR elements are ubiquitous Eukaryotic TEs that transpose through RNA intermediates. Accounting for significant proportion of many plant genomes, LTR elements have been well established as one of the major forces underlying the evolution of plant genome size, structure and function. The accessibility of more than 40% of genomic sequences of the model legume Medicago truncatula (Mt has made the comprehensive study of its LTR elements possible. Results We use a newly developed tool LTR_FINDER to identify LTR retrotransposons in the Mt genome and detect 526 full-length elements as well as a great number of copies related to them. These elements constitute about 9.6% of currently available genomic sequences. They are classified into 85 families of which 64 are reported for the first time. The majority of the LTR retrotransposons belong to either Copia or Gypsy superfamily and the others are categorized as TRIMs or LARDs by their length. We find that the copy-number of Copia-like families is 3 times more than that of Gypsy-like ones but the latter contribute more to the genome. The analysis of PBS and protein-coding domain structure of the LTR families reveals that they tend to use only 4–5 types of tRNAs and many families have quite conservative ORFs besides known TE domains. For several important families, we describe in detail their abundance, conservation, insertion time and structure. We investigate the amplification-deletion pattern of the elements and find that the detectable full-length elements are relatively young and most of them were inserted within the last 0.52 MY. We also estimate that more than ten million bp of the Mt genomic sequences have been removed by the deletion of LTR elements and the removal of the full-length structures in Mt has been more rapid than in rice. Conclusion This report is the first comprehensive description and analysis of LTR retrotransposons in the

  3. The G1/S Specific Cyclin D2 Is a Regulator of HIV-1 Restriction in Non-proliferating Cells

    Science.gov (United States)

    Badia, Roger; Pujantell, Maria; Riveira-Muñoz, Eva; Puig, Teresa; Torres-Torronteras, Javier; Martí, Ramón; Clotet, Bonaventura; Ampudia, Rosa M.; Ballana, Ester

    2016-01-01

    Macrophages are a heterogeneous cell population strongly influenced by differentiation stimuli that become susceptible to HIV-1 infection after inactivation of the restriction factor SAMHD1 by cyclin-dependent kinases (CDK). Here, we have used primary human monocyte-derived macrophages differentiated through different stimuli to evaluate macrophage heterogeneity on cell activation and proliferation and susceptibility to HIV-1 infection. Stimulation of monocytes with GM-CSF induces a non-proliferating macrophage population highly restrictive to HIV-1 infection, characterized by the upregulation of the G1/S-specific cyclin D2, known to control early steps of cell cycle progression. Knockdown of cyclin D2, enhances HIV-1 replication in GM-CSF macrophages through inactivation of SAMHD1 restriction factor by phosphorylation. Co-immunoprecipitation experiments show that cyclin D2 forms a complex with CDK4 and p21, a factor known to restrict HIV-1 replication by affecting the function of the downstream cascade that leads to SAMHD1 deactivation. Thus, we demonstrate that cyclin D2 acts as regulator of cell cycle proteins affecting SAMHD1-mediated HIV-1 restriction in non-proliferating macrophages. PMID:27541004

  4. Interferon-α regulates glutaminase 1 promoter through STAT1 phosphorylation: relevance to HIV-1 associated neurocognitive disorders.

    Directory of Open Access Journals (Sweden)

    Lixia Zhao

    Full Text Available HIV-1 associated neurocognitive disorders (HAND develop during progressive HIV-1 infection and affect up to 50% of infected individuals. Activated microglia and macrophages are critical cell populations that are involved in the pathogenesis of HAND, which is specifically related to the production and release of various soluble neurotoxic factors including glutamate. In the central nervous system (CNS, glutamate is typically derived from glutamine by mitochondrial enzyme glutaminase. Our previous study has shown that glutaminase is upregulated in HIV-1 infected monocyte-derived-macrophages (MDM and microglia. However, how HIV-1 leads to glutaminase upregulation, or how glutaminase expression is regulated in general, remains unclear. In this study, using a dual-luciferase reporter assay system, we demonstrated that interferon (IFN α specifically activated the glutaminase 1 (GLS1 promoter. Furthermore, IFN-α treatment increased signal transducer and activator of transcription 1 (STAT1 phosphorylation and glutaminase mRNA and protein levels. IFN-α stimulation of GLS1 promoter activity correlated to STAT1 phosphorylation and was reduced by fludarabine, a chemical that inhibits STAT1 phosphorylation. Interestingly, STAT1 was found to directly bind to the GLS1 promoter in MDM, an effect that was dependent on STAT1 phosphorylation and significantly enhanced by IFN-α treatment. More importantly, HIV-1 infection increased STAT1 phosphorylation and STAT1 binding to the GLS1 promoter, which was associated with increased glutamate levels. The clinical relevance of these findings was further corroborated with investigation of post-mortem brain tissues. The glutaminase C (GAC, one isoform of GLS1 mRNA levels in HIV associated-dementia (HAD individuals correlate with STAT1 (p<0.01, IFN-α (p<0.05 and IFN-β (p<0.01. Together, these data indicate that both HIV-1 infection and IFN-α treatment increase glutaminase expression through STAT1 phosphorylation and

  5. Development of 5 ' LTR DNA methylation of latent HIV-1 provirus in cell line models and in long-term-infected individuals

    Czech Academy of Sciences Publication Activity Database

    Trejbalová, Kateřina; Kovářová, Denisa; Blažková, Jana; Machala, L.; Jilich, D.; Weber, J.; Kučerová, Dana; Vencálek, O.; Hirsch, Ivan; Hejnar, Jiří

    2016-01-01

    Roč. 8, zima (2016), č. článku 19. ISSN 1868-7083 R&D Projects: GA ČR GAP304/12/1736 Institutional support: RVO:68378050 Keywords : HIV-1 * latent reservoir * DNA methylation * chromatin conformation * latent HIV-1 provirus reactivation * HIV-1-infected individuals Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 4.987, year: 2016

  6. Intrinsic Stability of Episomal Circles Formed during Human Immunodeficiency Virus Type 1 Replication

    Science.gov (United States)

    Pierson, TheodoreC.; Kieffer, Tara L.; Ruff, Christian T.; Buck, Christopher; Gange, Stephen J.; Siliciano, Robert F.

    2002-01-01

    The development of surrogate markers capable of detecting residual ongoing human immunodeficiency virus type 1 (HIV-1) replication in patients receiving highly active antiretroviral therapy is an important step in understanding viral dynamics and in developing new treatment strategies. In this study, we evaluated the utility of circular forms of the viral genome for the detection of recent infection of cells by HIV-1. We measured the fate of both one-long terminal repeat (1-LTR) and 2-LTR circles following in vitro infection of logarithmically growing CD4+ T cells under conditions in which cell death was not a significant contributing factor. Circular forms of the viral genome were found to be highly stable and to decrease in concentration only as a function of dilution resulting from cell division. We conclude that these DNA circles are not intrinsically unstable in all cell types and suggest that the utility of 2-LTR circle assays in measuring recent HIV-1 infection of susceptible cells in vivo needs to be reevaluated. PMID:11907256

  7. Development of 5' LTR DNA methylation of latent HIV-1 provirus in cell line models and in long-term-infected individuals

    Czech Academy of Sciences Publication Activity Database

    Trejbalová, K.; Kovářová, D.; Blažková, J.; Machala, L.; Jilich, D.; Weber, Jan; Kučerová, D.; Vencálek, O.; Hirsch, Ivan; Hejnar, J.

    2016-01-01

    Roč. 8, Feb 19 (2016), č. článku 19. ISSN 1868-7083 Institutional support: RVO:61388963 Keywords : HIV-1 * latent reservoir * DNA methylation * chromatin conformation * latent HIV-1 provirus reactivation * HIV-1-infected individuals Subject RIV: EE - Microbiology, Virology Impact factor: 4.987, year: 2016 http://clinicalepigeneticsjournal.biomedcentral.com/articles/10.1186/s13148-016-0185-6

  8. A Real Time PCR Platform for the Simultaneous Quantification of Total and Extrachromosomal HIV DNA Forms in Blood of HIV-1 Infected Patients

    Science.gov (United States)

    Canovari, Benedetta; Scotti, Maddalena; Acetoso, Marcello; Valentini, Massimo; Petrelli, Enzo; Magnani, Mauro

    2014-01-01

    Background The quantitative measurement of various HIV-1 DNA forms including total, unintegrated and integrated provirus play an increasingly important role in HIV-1 infection monitoring and treatment-related research. We report the development and validation of a SYBR Green real time PCR (TotUFsys platform) for the simultaneous quantification of total and extrachromosomal HIV-1 DNA forms in patients. This innovative technique makes it possible to obtain both measurements in a single PCR run starting from frozen blood employing the same primers and standard curve. Moreover, due to identical amplification efficiency, it allows indirect estimation of integrated level. To specifically detect 2-LTR a qPCR method was also developed. Methodology/Findings Primers used for total HIV-1 DNA quantification spanning a highly conserved region were selected and found to detect all HIV-1 clades of group M and the unintegrated forms of the same. A total of 195 samples from HIV-1 patients in a wide range of clinical conditions were analyzed with a 100% success rate, even in patients with suppressed plasma viremia, regardless of CD4+ or therapy. No significant correlation was observed between the two current prognostic markers, CD4+ and plasma viremia, while a moderate or high inverse correlation was found between CD4+ and total HIV DNA, with strong values for unintegrated HIV DNA. Conclusions/Significance Taken together, the results support the use of HIV DNA as another tool, in addition to traditional assays, which can be used to estimate the state of viral infection, the risk of disease progression and to monitor the effects of ART. The TotUFsys platform allowed us to obtain a final result, expressed as the total and unintegrated HIV DNA copy number per microgram of DNA or 104 CD4+, for 12 patients within two working days. PMID:25364909

  9. Full Length Research Paper LTR-retrotransposons-based molecular ...

    African Journals Online (AJOL)

    LTR-retrotransposons possess unique properties that make them appropriate for investigating relationships between closely related species and populations. The aim of the current study was to employ Ty1-copia group retrotransposons as molecular markers in cultivated Egyptian cottons, G. barbadense L. Restriction site ...

  10. An Analysis Of Pole/zero Cancellation In LTR-based Feedback Design

    DEFF Research Database (Denmark)

    Niemann, Hans Henrik; Jannerup, Ole Erik

    1990-01-01

    The pole/zero cancellation in LTR-based feedback design will be analyzed for both full-order as well as minimal-order observers. The asymptotic behaviour of the sensitivity function from the LTR-procedure are given in explicit expressions in the case when a zero is not cancelled by an equivalent...... pole. It will be shown that the non-minimum phase case is included as a special case. The results are not based on any specific LTR-method....

  11. HIV-1 Tat regulates the expression of the dcw operon and stimulates the proliferation of bacteria.

    Science.gov (United States)

    Wei, Jinsong; Zhang, Yumin; Knapp, Pamela E; Zhao, Tianyong

    2016-01-01

    Infections of pathogenic bacteria are very common in acquired immunodeficiency syndrome (AIDS) patients. However, the biological effects of HIV-1 Tat on bacteria are incompletely understood. In this study, HIV-1 Tat was expressed in Escherichia coli and Pseudomonas aeruginosa (PA01) to investigate its biological effects on bacteria. Bacterial cells expressing either HIV-1 Tat1-86 (Tat1-86) or HIV-1 Tat1-72 (Tat1-72) grow significantly faster than those with either only an empty vector or an unrelated control (GFP or Rluc). Supplementation of purified HIV-1 Tat1-86 or Tat1-101 protein into bacterial culture medium stimulated the growth of both E. coli and PA01. The expression profile of certain cell division-associated genes, such as those in the division cell wall (dcw) operon (ftsA, ftsQ, ftsW and ftsZ), yafO and zipA, was altered in HIV-1 Tat1-86 expressing E. coli BL21(DE3). Furthermore, the expression of firefly luciferase (Fluc) reporter gene, when engineered for control by the dcw promoter and terminator, was enhanced by HIV-1 Tat in E. coli, confirming that HIV-1 Tat transcriptionally regulates the expression of the dcw operon. The finding that HIV-1 Tat stimulates bacterial growth whether it is produced intracellularly or applied extracellularly may have relevance for HIV patients who are highly susceptible to opportunistic bacterial infections. Contents category: Viruses -Retroviruses. The GenBank accession number for the sequence of HIV-1 Tat1-86 is AF324439.1. Copyright © 2015 Elsevier Ltd. All rights reserved.

  12. HIV-1 uncoating: connection to nuclear entry and regulation by host proteins

    Energy Technology Data Exchange (ETDEWEB)

    Ambrose, Zandrea, E-mail: zaa4@pitt.edu [Division of Infectious Diseases, Department of Medicine, University of Pittsburgh, School of Medicine, Pittsburgh, PA 15261 (United States); Aiken, Christopher [Department of Pathology, Microbiology and Immunology, Vanderbilt University, School of Medicine, Nashville, TN 37232 (United States)

    2014-04-15

    The RNA genome of human immunodeficiency virus type 1 (HIV-1) is enclosed by a capsid shell that dissociates within the cell in a multistep process known as uncoating, which influences completion of reverse transcription of the viral genome. Double-stranded viral DNA is imported into the nucleus for integration into the host genome, a hallmark of retroviral infection. Reverse transcription, nuclear entry, and integration are coordinated by a capsid uncoating process that is regulated by cellular proteins. Although uncoating is not well understood, recent studies have revealed insights into the process, particularly with respect to nuclear import pathways and protection of the viral genome from DNA sensors. Understanding uncoating will be valuable toward developing novel antiretroviral therapies for HIV-infected individuals.

  13. Methamphetamine inhibits HIV-1 replication in CD4+ T cells by modulating anti-HIV-1 miRNA expression.

    Science.gov (United States)

    Mantri, Chinmay K; Mantri, Jyoti V; Pandhare, Jui; Dash, Chandravanu

    2014-01-01

    Methamphetamine is the second most frequently used illicit drug in the United States. Methamphetamine abuse is associated with increased risk of HIV-1 acquisition, higher viral loads, and enhanced HIV-1 pathogenesis. Although a direct link between methamphetamine abuse and HIV-1 pathogenesis remains to be established in patients, methamphetamine has been shown to increase HIV-1 replication in macrophages, dendritic cells, and cells of HIV transgenic mice. Intriguingly, the effects of methamphetamine on HIV-1 replication in human CD4(+) T cells that serve as the primary targets of infection in vivo are not clearly understood. Therefore, we examined HIV-1 replication in primary CD4(+) T cells in the presence of methamphetamine in a dose-dependent manner. Our results demonstrate that methamphetamine had a minimal effect on HIV-1 replication at concentrations of 1 to 50 μmol/L. However, at concentrations >100 μmol/L, it inhibited HIV-1 replication in a dose-dependent manner. We also discovered that methamphetamine up-regulated the cellular anti-HIV-1 microRNAs (miR-125b, miR-150, and miR-28-5p) in CD4(+) T cells. Knockdown experiments illustrated that up-regulation of the anti-HIV miRNAs inhibited HIV-1 replication. These results are contrary to the paradigm that methamphetamine accentuates HIV-1 pathogenesis by increasing HIV-1 replication. Therefore, our findings underline the complex interaction between drug use and HIV-1 and necessitate comprehensive understanding of the effects of methamphetamine on HIV-1 pathogenesis. Copyright © 2014 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.

  14. HIV-1 gp120 induces NFAT nuclear translocation in resting CD4+ T-cells

    International Nuclear Information System (INIS)

    Cicala, Claudia; Arthos, James; Censoplano, Nina; Cruz, Catherine; Chung, Eva; Martinelli, Elena; Lempicki, Richard A.; Natarajan, Ven; VanRyk, Donald; Daucher, Marybeth; Fauci, Anthony S.

    2006-01-01

    The replication of human immunodeficiency virus (HIV) in CD4+ T-cells is strongly dependent upon the state of activation of infected cells. Infection of sub-optimally activated cells is believed to play a critical role in both the transmission of virus and the persistence of CD4+ T-cell reservoirs. There is accumulating evidence that HIV can modulate signal-transduction pathways in a manner that may facilitate replication in such cells. We previously demonstrated that HIV gp120 induces virus replication in resting CD4+ T cells isolated from HIV-infected individuals. Here, we show that in resting CD4+ T-cells, gp120 activates NFATs and induces their translocation into the nucleus. The HIV LTR encodes NFAT recognition sites, and NFATs may play a critical role in promoting viral replication in sub-optimally activated cells. These observations provide insight into a potential mechanism by which HIV is able to establish infection in resting cells, which may have implications for both transmission of HIV and the persistence of viral reservoirs

  15. The C-terminal sequence of IFITM1 regulates its anti-HIV-1 activity.

    Directory of Open Access Journals (Sweden)

    Rui Jia

    Full Text Available The interferon-inducible transmembrane (IFITM proteins inhibit a wide range of viruses. We previously reported the inhibition of human immunodeficiency virus type 1 (HIV-1 strain BH10 by human IFITM1, 2 and 3. It is unknown whether other HIV-1 strains are similarly inhibited by IFITMs and whether there exists viral countermeasure to overcome IFITM inhibition. We report here that the HIV-1 NL4-3 strain (HIV-1NL4-3 is not restricted by IFITM1 and its viral envelope glycoprotein is partly responsible for this insensitivity. However, HIV-1NL4-3 is profoundly inhibited by an IFITM1 mutant, known as Δ(117-125, which is deleted of 9 amino acids at the C-terminus. In contrast to the wild type IFITM1, which does not affect HIV-1 entry, the Δ(117-125 mutant diminishes HIV-1NL4-3 entry by 3-fold. This inhibition correlates with the predominant localization of Δ(117-125 to the plasma membrane where HIV-1 entry occurs. In spite of strong conservation of IFITM1 among most species, mouse IFITM1 is 19 amino acids shorter at its C-terminus as compared to human IFITM1 and, like the human IFITM1 mutant Δ(117-125, mouse IFITM1 also inhibits HIV-1 entry. This is the first report illustrating the role of viral envelope protein in overcoming IFITM1 restriction. The results also demonstrate the importance of the C-terminal region of IFITM1 in modulating the antiviral function through controlling protein subcellular localization.

  16. Human immunodeficiency virus type 1 KK26-27 matrix mutants display impaired infectivity, circularization and integration but not nuclear import

    International Nuclear Information System (INIS)

    Mannioui, Abdelkrim; Nelson, Elisabeth; Schiffer, Cecile

    2005-01-01

    We analyzed the role of human immunodeficiency virus (HIV)-1 matrix protein (MA) during the virus replication afferent phase. Single-round infection of H9 T lymphocytes showed that the combined mutation of MA Lys residues 26-27 in MA reported nuclear localization signal (NLS)-1 [Haffar, O.K., Popov, S., Dubrovsky, L., Agostini, I., Tang, H., Pushkarsky, T., Nadler, S.G., Bukrinsky, M., 2000. Two nuclear localization signals in the HIV-1 matrix protein regulate nuclear import of the HIV-1 pre-integration complex. J. Mol. Biol. 299 (2): 359-368] impaired infectivity, abrogated 2-LTR-circle formation and significantly reduced integration. However, the mutation did not affect viral DNA docking to chromatin in either interphasic or mitotic cells, indicating that MA N-terminal basic domain should not represent a major determinant of HIV-1 nuclear import in T lymphocytes. These data point to a previously unreported role of MA in the late, post-chromatin-binding, afferent phase of HIV-1 replication cycle

  17. HIV-1 Tat C-mediated regulation of tumor necrosis factor receptor-associated factor-3 by microRNA 32 in human microglia

    Directory of Open Access Journals (Sweden)

    Mishra Ritu

    2012-06-01

    Full Text Available Abstract Background HIV-1 Tat protein is known to be associated with neuroinflammation, a condition that develops in almost half of patients infected with HIV-1. HIV-1 Tat can alter glial neuroprotective functions, leading to neurotoxicity within the CNS. HIV-1 Tat is known to be secreted from productively infected cells and can affect neighboring uninfected cells by modulating cellular gene expression in a bystander fashion. Methods We were interested to study whether exogenous exposure to HIV-1 Tat-C protein perturbs the microRNA (miRNA expression profile of human microglial cells, leading to altered protein expression. We used protein expression and purification, miRNA overexpression, miRNA knockdown, transfection, site-directed mutagenesis, real-time PCR, luciferase assay and western blotting techniques to perform our study. Results HIV-1 Tat-C treatment of human microglial cells resulted in a dose-dependent increase in miR-32 expression. We found that tumor necrosis factor-receptor–associated factor 3 TRAF3 is a direct target for miR-32, and overexpression of miR-32 in CHME3 cells decreased TRAF3 both at the mRNA and the protein level. Recovery of TRAF3 protein expression after transfection of anti-miR-32 and the results of the luciferase reporter assay provided direct evidence of TRAF3 regulation by miR-32. We found that the regulation of interferon regulatory factor 3 (IRF3 and IRF7 is controlled by cellular levels of TRAF3 protein in microglial cells, as after overexpression of miR-32 and application of anti-miR-32, expression levels of IRF3 and IRF7 were inversely regulated by expression levels of TRAF3. Thus, our results suggest a novel miRNA mediated mechanism for regulation of TRAF3 in human microglial cells exposed to HIV-1 Tat C protein. These results may help to elucidate the detrimental neuroinflammatory consequences of HIV-1 Tat C protein in bystander fashion. Conclusion HIV-1 Tat protein can modulate TRAF3 expression through

  18. HIV-1 resistance dynamics in patients failing dolutegravir maintenance monotherapy.

    Science.gov (United States)

    Wijting, Ingeborg E A; Lungu, Cynthia; Rijnders, Bart J A; van der Ende, Marchina E; Pham, Hanh T; Mesplede, Thibault; Pas, Suzan D; Voermans, Jolanda J C; Schuurman, Rob; van de Vijver, David A M C; Boers, Patrick H M; Gruters, Rob A; Boucher, Charles A B; van Kampen, Jeroen J A

    2018-03-29

    A high genetic resistance barrier to the integrase-strand-transfer-inhibitor (INSTI) dolutegravir has been reported in vitro and in vivo. We describe the dynamics of INSTI-resistance-associated-mutations (INSTI-RAMs) and mutations in the 3'-polypurine tract (3'-PPT) in relation to virological failure (VF) observed in the randomized dolutegravir maintenance monotherapy study (DOMONO, NCT02401828). From ten patients with VF plasma samples prior to start cART and during VF were used to generate Sanger sequences of integrase, the 5' terminal bases of the 3'- LTR, and the 3'-PPT. Median HIV-RNA (IQR) at VF was 3,490 (1,440-4,990) c/mL. INSTI-RAMs were detected in 4/10 patients (S230R, R263K, N155H, E92Q+N155H) and in 4/10 patients no INSTI-RAMs were detected (2/10 patients integrase sequencing was unsuccessful). The time-to-VF ranged from 4 weeks to 72 weeks. In one patient, mutations developed in the highly conserved 3'-PPT. No changes in the terminal bases of the 3'-LTR were observed. The genetic barrier to resistance is too low to justify dolutegravir maintenance monotherapy as single INSTI-RAMs are sufficient to cause VF. The large variation in time-to-VF suggests that stochastic reactivation of a pre-existing provirus containing a single INSTI-RAM is the mechanism for failure. Changes in the 3'-PPT point to a new dolutegravir resistance mechanism in vivo.

  19. Selection of reliable reference genes for gene expression studies in Trichoderma afroharzianum LTR-2 under oxalic acid stress.

    Science.gov (United States)

    Lyu, Yuping; Wu, Xiaoqing; Ren, He; Zhou, Fangyuan; Zhou, Hongzi; Zhang, Xinjian; Yang, Hetong

    2017-10-01

    An appropriate reference gene is required to get reliable results from gene expression analysis by quantitative real-time reverse transcription PCR (qRT-PCR). In order to identify stable and reliable reference genes in Trichoderma afroharzianum under oxalic acid (OA) stress, six commonly used housekeeping genes, i.e., elongation factor 1, ubiquitin, ubiquitin-conjugating enzyme, glyceraldehyde-3-phosphate dehydrogenase, α-tubulin, actin, from the effective biocontrol isolate T. afroharzianum strain LTR-2 were tested for their expression during growth in liquid culture amended with OA. Four in silico programs (comparative ΔCt, NormFinder, geNorm and BestKeeper) were used to evaluate the expression stabilities of six candidate reference genes. The elongation factor 1 gene EF-1 was identified as the most stably expressed reference gene, and was used as the normalizer to quantify the expression level of the oxalate decarboxylase coding gene OXDC in T. afroharzianum strain LTR-2 under OA stress. The result showed that the expression of OXDC was significantly up-regulated as expected. This study provides an effective method to quantify expression changes of target genes in T. afroharzianum under OA stress. Copyright © 2017 Elsevier B.V. All rights reserved.

  20. Tat-dependent repression of human immunodeficiency virus type 1 long terminal repeat promoter activity by fusion of cellular transcription factors

    International Nuclear Information System (INIS)

    Zhao Cunyou; Chen Yali; Park, Jiyoung; Kim, Jae Bum; Tang Hong

    2004-01-01

    Transcription initiation from HIV-1 long terminal repeat (LTR) promoter requires the virally encoded transactivator, Tat, and several cellular co-factors to accomplish the Tat-dependent processive transcription elongation. Individual cellular transcription activators, LBP-1b and Oct-1, on the other hand, have been shown to inhibit LTR promoter activities probably via competitive binding against TFIID to the TATA-box in LTR promoter. To explore the genetic interference strategies against the viral replication, we took advantage of the existence of the bipartite DNA binding domains and the repression domains of LBP-1b and Oct-1 factors to generate a chimeric transcription repressor. Our results indicated that the fusion protein of LBP-1b and Oct-1 exhibited higher DNA binding affinity to the viral promoter than the individual factors, and little interference with the host cell gene expression due to its anticipated rare cognate DNA sites in the host cell genome. Moreover, the chimera exerted increased Tat-dependent repression of transcription initiation at the LTR promoter both in vitro and in vivo compared to LBP-1b, Oct-1 or combination of LBP-1b and Oct-1. These results might provide the lead in generating a therapeutic reagent useful to suppress HIV-1 replication

  1. A novel function for spumaretrovirus integrase: an early requirement for integrase-mediated cleavage of 2 LTR circles

    Directory of Open Access Journals (Sweden)

    Mouscadet Jean-François

    2005-05-01

    Full Text Available Abstract Retroviral integration is central to viral persistence and pathogenesis, cancer as well as host genome evolution. However, it is unclear why integration appears essential for retrovirus production, especially given the abundance and transcriptional potential of non-integrated viral genomes. The involvement of retroviral endonuclease, also called integrase (IN, in replication steps apart from integration has been proposed, but is usually considered to be accessory. We observe here that integration of a retrovirus from the spumavirus family depends mainly on the quantity of viral DNA produced. Moreover, we found that IN directly participates to linear DNA production from 2-LTR circles by specifically cleaving the conserved palindromic sequence found at LTR-LTR junctions. These results challenge the prevailing view that integrase essential function is to catalyze retroviral DNA integration. Integrase activity upstream of this step, by controlling linear DNA production, is sufficient to explain the absolute requirement for this enzyme. The novel role of IN over 2-LTR circle junctions accounts for the pleiotropic effects observed in cells infected with IN mutants. It may explain why 1 2-LTR circles accumulate in vivo in mutants carrying a defective IN while their linear and integrated DNA pools decrease; 2 why both LTRs are processed in a concerted manner. It also resolves the original puzzle concerning the integration of spumaretroviruses. More generally, it suggests to reassess 2-LTR circles as functional intermediates in the retrovirus cycle and to reconsider the idea that formation of the integrated provirus is an essential step of retrovirus production.

  2. Development of TIMP1 magnetic nanoformulation for regulation of synaptic plasticity in HIV-1 infection

    Directory of Open Access Journals (Sweden)

    Atluri VSR

    2016-08-01

    Full Text Available Venkata Subba Rao Atluri* Rahul Dev Jayant* Sudheesh Pilakka-Kanthikeel, Gabriella Garcia, Thangavel Samikkannu, Adriana Yndart, Ajeet Kaushik, Madhavan Nair Center for Personalized Nanomedicine, Department of Immunology, Herbert Wertheim College of Medicine, Florida International University, Miami, FL, USA *These authors contributed equally to this work Abstract: Although the introduction of antiretroviral therapy has reduced the prevalence of severe forms of neurocognitive disorders, human immunodeficiency virus (HIV-1-associated neurocognitive disorders were observed in 50% of HIV-infected patients globally. The blood–brain barrier is known to be impermeable to most of antiretroviral drugs. Successful delivery of antiretroviral drugs into the brain may induce an inflammatory response, which may further induce neurotoxicity. Therefore, alternate options to antiretroviral drugs for decreasing the HIV infection and neurotoxicity may help in reducing neurocognitive impairments observed in HIV-infected patients. In this study, we explored the role of magnetic nanoparticle (MNP-bound tissue inhibitor of metalloproteinase-1 (TIMP1 protein in reducing HIV infection levels, oxidative stress, and recovering spine density in HIV-infected SK-N-MC neuroblastoma cells. We did not observe any neuronal cytotoxicity with either the free TIMP1 or MNP-bound TIMP1 used in our study. We observed significantly reduced HIV infection in both solution phase and in MNP-bound TIMP1-exposed neuronal cells. Furthermore, we also observed significantly reduced reactive oxygen species production in both the test groups compared to the neuronal cells infected with HIV alone. To observe the effect of both soluble-phase TIMP1 and MNP-bound TIMP1 on spine density in HIV-infected neuronal cells, confocal microscopy was used. We observed significant recovery of spine density in both the test groups when compared to the cells infected with HIV alone, indicting the

  3. Functional Impairment of Myeloid Dendritic Cells during Advanced Stage of HIV-1 Infection: Role of Factors Regulating Cytokine Signaling.

    Directory of Open Access Journals (Sweden)

    Meenakshi Sachdeva

    Full Text Available Severely immunocompromised state during advanced stage of HIV-1 infection has been linked to functionally defective antigen presentation by dendritic cells (DCs. The molecular mechanisms behind DC impairment are still obscure. We investigated changes in DC function and association of key regulators of cytokine signaling during different stages of HIV-1 infection and following antiretroviral therapy (ART.Phenotypic and functional characteristics of circulating myeloid DCs (mDCs in 56 ART-naive patients (23 in early and 33 in advanced stage of disease, 36 on ART and 24 healthy controls were evaluated. Sixteen patients were studied longitudinally prior-to and 6 months after the start of ART. For functional studies, monocyte-derived DCs (Mo-DCs were evaluated for endocytosis, allo-stimulation and cytokine secretion. The expression of suppressor of cytokine signaling (SOCS-1 and other regulators of cytokine signaling was evaluated by real-time RT-PCR.The ability to respond to an antigenic stimulation was severely impaired in patients in advanced HIV-1 disease which showed partial recovery in the treated group. Mo-DCs from patients with advanced HIV-disease remained immature with low allo-stimulation and reduced cytokine secretion even after TLR-4 mediated stimulation ex-vivo. The cells had an increased expression of negative regulatory factors like SOCS-1, SOCS-3, SH2-containing phosphatase (SHP-1 and a reduced expression of positive regulators like Janus kinase (JAK2 and Nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB1. A functional recovery after siRNA mediated silencing of SOCS-1 in these mo-DCs confirms the role of negative regulatory factors in functional impairment of these cells.Functionally defective DCs in advanced stage of HIV-1 infection seems to be due to imbalanced state of negative and positive regulatory gene expression. Whether this is a cause or effect of increased viral replication at this stage of disease

  4. Identification of a non-LTR retrotransposon from the gypsy moth

    Science.gov (United States)

    K.J. Garner; J.M. Slavicek

    1999-01-01

    A family of highly repetitive elements, named LDT1, has been identified in the gypsy moth, Lymantria dispar. The complete element is 5.4 kb in length and lacks long-terminal repeats, The element contains two open reading frames with a significant amino acid sequence similarity to several non-LTR retrotransposons. The first open reading frame contains...

  5. Alcohol and cannabinoids differentially affect HIV infection and function of human monocyte-derived dendritic cells (MDDC

    Directory of Open Access Journals (Sweden)

    Marisela eAgudelo

    2015-12-01

    Full Text Available During human immunodeficiency virus (HIV infection, alcohol has been known to induce inflammation while cannabinoids have been shown to have an anti-inflammatory role. For instance cannabinoids have been shown to reduce susceptibility to HIV-1 infection and attenuate HIV replication in macrophages. Recently, we demonstrated that alcohol induces cannabinoid receptors and regulates cytokine production by monocyte-derived dendritic cells (MDDC. However, the ability of alcohol and cannabinoids to alter MDDC function during HIV infection has not been clearly elucidated yet. In order to study the potential impact of alcohol and cannabinoids on differentiated MDDC infected with HIV, monocytes were cultured for 7 days with GM-CSF and IL-4, differentiated MDDC were infected with HIV-1Ba-L and treated with EtOH (0.1 and 0.2%, THC (5 and 10 uM, or JWH-015 (5 and 10 uM for 4-7 days. HIV infection of MDDC was confirmed by p24 and Long Terminal Repeats (LTR estimation. MDDC endocytosis assay and cytokine array profiles were measured to investigate the effects of HIV and substances of abuse on MDDC function. Our results show the HIV+EtOH treated MDDC had the highest levels of p24 production and expression when compared with the HIV positive controls and the cannabinoid treated cells. Although both cannabinoids, THC and JWH-015 had lower levels of p24 production and expression, the HIV+JWH-015 treated MDDC had the lowest levels of p24 when compared to the HIV+THC treated cells. In addition, MDDC endocytic function and cytokine production were also differentially altered after alcohol and cannabinoid treatments. Our results show a differential effect of alcohol and cannabinoids, which may provide insights into the divergent inflammatory role of alcohol and cannabinoids to modulate MDDC function in the context of HIV infection.

  6. SAMHD1 controls cell cycle status, apoptosis and HIV-1 infection in monocytic THP-1 cells

    International Nuclear Information System (INIS)

    Bonifati, Serena; Daly, Michele B.; St Gelais, Corine; Kim, Sun Hee; Hollenbaugh, Joseph A.; Shepard, Caitlin; Kennedy, Edward M.; Kim, Dong-Hyun; Schinazi, Raymond F.; Kim, Baek; Wu, Li

    2016-01-01

    SAMHD1 limits HIV-1 infection in non-dividing myeloid cells by decreasing intracellular dNTP pools. HIV-1 restriction by SAMHD1 in these cells likely prevents activation of antiviral immune responses and modulates viral pathogenesis, thus highlighting a critical role of SAMHD1 in HIV-1 physiopathology. Here, we explored the function of SAMHD1 in regulating cell proliferation, cell cycle progression and apoptosis in monocytic THP-1 cells. Using the CRISPR/Cas9 technology, we generated THP-1 cells with stable SAMHD1 knockout. We found that silencing of SAMHD1 in cycling cells stimulates cell proliferation, redistributes cell cycle population in the G_1/G_0 phase and reduces apoptosis. These alterations correlated with increased dNTP levels and more efficient HIV-1 infection in dividing SAMHD1 knockout cells relative to control. Our results suggest that SAMHD1, through its dNTPase activity, affects cell proliferation, cell cycle distribution and apoptosis, and emphasize a key role of SAMHD1 in the interplay between cell cycle regulation and HIV-1 infection.

  7. SAMHD1 controls cell cycle status, apoptosis and HIV-1 infection in monocytic THP-1 cells

    Energy Technology Data Exchange (ETDEWEB)

    Bonifati, Serena [Center for Retrovirus Research, Department of Veterinary Biosciences, The Ohio State University, Columbus, OH (United States); Daly, Michele B. [Center for Drug Discovery, Department of Pediatrics, School of Medicine, Emory University, Atlanta, GA (United States); St Gelais, Corine; Kim, Sun Hee [Center for Retrovirus Research, Department of Veterinary Biosciences, The Ohio State University, Columbus, OH (United States); Hollenbaugh, Joseph A.; Shepard, Caitlin [Center for Drug Discovery, Department of Pediatrics, School of Medicine, Emory University, Atlanta, GA (United States); Kennedy, Edward M. [Department of Molecular Genetics and Microbiology, Duke University, Durham, NC (United States); Kim, Dong-Hyun [Department of Pharmacy, School of Pharmacy, Kyung-Hee University, Seoul (Korea, Republic of); Schinazi, Raymond F. [Center for Drug Discovery, Department of Pediatrics, School of Medicine, Emory University, Atlanta, GA (United States); Kim, Baek, E-mail: baek.kim@emory.edu [Center for Drug Discovery, Department of Pediatrics, School of Medicine, Emory University, Atlanta, GA (United States); Department of Pharmacy, School of Pharmacy, Kyung-Hee University, Seoul (Korea, Republic of); Wu, Li, E-mail: wu.840@osu.edu [Center for Retrovirus Research, Department of Veterinary Biosciences, The Ohio State University, Columbus, OH (United States)

    2016-08-15

    SAMHD1 limits HIV-1 infection in non-dividing myeloid cells by decreasing intracellular dNTP pools. HIV-1 restriction by SAMHD1 in these cells likely prevents activation of antiviral immune responses and modulates viral pathogenesis, thus highlighting a critical role of SAMHD1 in HIV-1 physiopathology. Here, we explored the function of SAMHD1 in regulating cell proliferation, cell cycle progression and apoptosis in monocytic THP-1 cells. Using the CRISPR/Cas9 technology, we generated THP-1 cells with stable SAMHD1 knockout. We found that silencing of SAMHD1 in cycling cells stimulates cell proliferation, redistributes cell cycle population in the G{sub 1}/G{sub 0} phase and reduces apoptosis. These alterations correlated with increased dNTP levels and more efficient HIV-1 infection in dividing SAMHD1 knockout cells relative to control. Our results suggest that SAMHD1, through its dNTPase activity, affects cell proliferation, cell cycle distribution and apoptosis, and emphasize a key role of SAMHD1 in the interplay between cell cycle regulation and HIV-1 infection.

  8. Differentially-Expressed Pseudogenes in HIV-1 Infection

    Directory of Open Access Journals (Sweden)

    Aditi Gupta

    2015-09-01

    Full Text Available Not all pseudogenes are transcriptionally silent as previously thought. Pseudogene transcripts, although not translated, contribute to the non-coding RNA pool of the cell that regulates the expression of other genes. Pseudogene transcripts can also directly compete with the parent gene transcripts for mRNA stability and other cell factors, modulating their expression levels. Tissue-specific and cancer-specific differential expression of these “functional” pseudogenes has been reported. To ascertain potential pseudogene:gene interactions in HIV-1 infection, we analyzed transcriptomes from infected and uninfected T-cells and found that 21 pseudogenes are differentially expressed in HIV-1 infection. This is interesting because parent genes of one-third of these differentially-expressed pseudogenes are implicated in HIV-1 life cycle, and parent genes of half of these pseudogenes are involved in different viral infections. Our bioinformatics analysis identifies candidate pseudogene:gene interactions that may be of significance in HIV-1 infection. Experimental validation of these interactions would establish that retroviruses exploit this newly-discovered layer of host gene expression regulation for their own benefit.

  9. Differentially-Expressed Pseudogenes in HIV-1 Infection.

    Science.gov (United States)

    Gupta, Aditi; Brown, C Titus; Zheng, Yong-Hui; Adami, Christoph

    2015-09-29

    Not all pseudogenes are transcriptionally silent as previously thought. Pseudogene transcripts, although not translated, contribute to the non-coding RNA pool of the cell that regulates the expression of other genes. Pseudogene transcripts can also directly compete with the parent gene transcripts for mRNA stability and other cell factors, modulating their expression levels. Tissue-specific and cancer-specific differential expression of these "functional" pseudogenes has been reported. To ascertain potential pseudogene:gene interactions in HIV-1 infection, we analyzed transcriptomes from infected and uninfected T-cells and found that 21 pseudogenes are differentially expressed in HIV-1 infection. This is interesting because parent genes of one-third of these differentially-expressed pseudogenes are implicated in HIV-1 life cycle, and parent genes of half of these pseudogenes are involved in different viral infections. Our bioinformatics analysis identifies candidate pseudogene:gene interactions that may be of significance in HIV-1 infection. Experimental validation of these interactions would establish that retroviruses exploit this newly-discovered layer of host gene expression regulation for their own benefit.

  10. Low levels of LTR retrotransposon deletion by ectopic recombination in the gigantic genomes of salamanders.

    Science.gov (United States)

    Frahry, Matthew Blake; Sun, Cheng; Chong, Rebecca A; Mueller, Rachel Lockridge

    2015-02-01

    Across the tree of life, species vary dramatically in nuclear genome size. Mutations that add or remove sequences from genomes-insertions or deletions, or indels-are the ultimate source of this variation. Differences in the tempo and mode of insertion and deletion across taxa have been proposed to contribute to evolutionary diversity in genome size. Among vertebrates, most of the largest genomes are found within the salamanders, an amphibian clade with genome sizes ranging from ~14 to ~120 Gb. Salamander genomes have been shown to experience slower rates of DNA loss through small (i.e., genomes. However, no studies have addressed DNA loss from salamander genomes resulting from larger deletions. Here, we focus on one type of large deletion-ectopic-recombination-mediated removal of LTR retrotransposon sequences. In ectopic recombination, double-strand breaks are repaired using a "wrong" (i.e., ectopic, or non-allelic) template sequence-typically another locus of similar sequence. When breaks occur within the LTR portions of LTR retrotransposons, ectopic-recombination-mediated repair can produce deletions that remove the internal transposon sequence and the equivalent of one of the two LTR sequences. These deletions leave a signature in the genome-a solo LTR sequence. We compared levels of solo LTRs in the genomes of four salamander species with levels present in five vertebrates with smaller genomes. Our results demonstrate that salamanders have low levels of solo LTRs, suggesting that ectopic-recombination-mediated deletion of LTR retrotransposons occurs more slowly than in other vertebrates with smaller genomes.

  11. Inhibition of both HIV-1 reverse transcription and gene expression by a cyclic peptide that binds the Tat-transactivating response element (TAR RNA.

    Directory of Open Access Journals (Sweden)

    Matthew S Lalonde

    2011-05-01

    Full Text Available The RNA response element TAR plays a critical role in HIV replication by providing a binding site for the recruitment of the viral transactivator protein Tat. Using a structure-guided approach, we have developed a series of conformationally-constrained cyclic peptides that act as structural mimics of the Tat RNA binding region and block Tat-TAR interactions at nanomolar concentrations in vitro. Here we show that these compounds block Tat-dependent transcription in cell-free systems and in cell-based reporter assays. The compounds are also cell permeable, have low toxicity, and inhibit replication of diverse HIV-1 strains, including both CXCR4-tropic and CCR5-tropic primary HIV-1 isolates of the divergent subtypes A, B, C, D and CRF01_AE. In human peripheral blood mononuclear cells, the cyclic peptidomimetic L50 exhibited an IC(50 ∼250 nM. Surprisingly, inhibition of LTR-driven HIV-1 transcription could not account for the full antiviral activity. Timed drug-addition experiments revealed that L-50 has a bi-phasic inhibition curve with the first phase occurring after HIV-1 entry into the host cell and during the initiation of HIV-1 reverse transcription. The second phase coincides with inhibition of HIV-1 transcription. Reconstituted reverse transcription assays confirm that HIV-1 (- strand strong stop DNA synthesis is blocked by L50-TAR RNA interactions in-vitro. These findings are consistent with genetic evidence that TAR plays critical roles both during reverse transcription and during HIV gene expression. Our results suggest that antiviral drugs targeting TAR RNA might be highly effective due to a dual inhibitory mechanism.

  12. Insertion of a solo LTR retrotransposon associates with spur mutations in 'Red Delicious' apple (Malus × domestica).

    Science.gov (United States)

    Han, Mengxue; Sun, Qibao; Zhou, Junyong; Qiu, Huarong; Guo, Jing; Lu, Lijuan; Mu, Wenlei; Sun, Jun

    2017-09-01

    Insertion of a solo LTR, which possesses strong bidirectional, stem-specific promoter activities, is associated with the evolution of a dwarfing apple spur mutation. Spur mutations in apple scions revolutionized global apple production. Since long terminal repeat (LTR) retrotransposons are tightly related to natural mutations, inter-retrotransposon-amplified polymorphism technique and genome walking were used to find sequences in the apple genome based on these LTRs. In 'Red Delicious' spur mutants, a novel, 2190-bp insertion was identified as a spur-specific, solo LTR (sLTR) located at the 1038th nucleotide of another sLTR, which was 1536 bp in length. This insertion-within-an-insertion was localized within a preexisting Gypsy-50 retrotransposon at position 3,762,767 on chromosome 4. The analysis of transcriptional activity of the two sLTRs (the 2190- and 1536-bp inserts) indicated that the 2190-bp sLTR is a promoter, capable of bidirectional transcription. GUS expression in the 2190-bp-sense and 2190-bp-antisense transgenic lines was prominent in stems. In contrast, no promoter activity from either the sense or the antisense strand of the 1536-bp sLTR was detected. From ~150 kb of DNA on each side of the 2190 bp, sLTR insertion site, corresponding to 300 kb of the 'Golden Delicious' genome, 23 genes were predicted. Ten genes had predicted functions that could affect shoot development. This first report, of a sLTR insertion associated with the evolution of apple spur mutation, will facilitate apple breeding, cloning of spur-related genes, and discovery of mechanisms behind dwarf habit.

  13. Up-regulation of the Neuronal Nicotinic Receptor α7 by HIV Glycoprotein 120

    Science.gov (United States)

    Ballester, Leomar Y.; Capó-Vélez, Coral M.; García-Beltrán, Wilfredo F.; Ramos, Félix M.; Vázquez-Rosa, Edwin; Ríos, Raymond; Mercado, José R.; Meléndez, Roberto I.; Lasalde-Dominicci, José A.

    2012-01-01

    Approximately 30–50% of the >30 million HIV-infected subjects develop neurological complications ranging from mild symptoms to dementia. HIV does not infect neurons, and the molecular mechanisms behind HIV-associated neurocognitive decline are not understood. There are several hypotheses to explain the development of dementia in HIV+ individuals, including neuroinflammation mediated by infected microglia and neuronal toxicity by HIV proteins. A key protein associated with the neurological complications of HIV, gp120, forms part of the viral envelope and can be found in the CSF of infected individuals. HIV-1-gp120 interacts with several receptors including CD4, CCR5, CXCR4, and nicotinic acetylcholine receptors (nAChRs). However, the role of nAChRs in HIV-associated neurocognitive disorder has not been investigated. We studied the effects of gp120IIIB on the expression and function of the nicotinic receptor α7 (α7-nAChR). Our results show that gp120, through activation of the CXCR4 chemokine receptor, induces a functional up-regulation of α7-nAChRs. Because α7-nAChRs have a high permeability to Ca2+, we performed TUNEL staining to investigate the effects of receptor up-regulation on cell viability. Our data revealed an increase in cell death, which was blocked by the selective antagonist α-bungarotoxin. The in vitro data are supported by RT-PCR and Western blot analysis, confirming a remarkable up-regulation of the α7-nAChR in gp120-transgenic mice brains. Specifically, α7-nAChR up-regulation is observed in mouse striatum, a region severely affected in HIV+ patients. In summary, CXCR4 activation induces up-regulation of α7-nAChR, causing cell death, suggesting that α7-nAChR is a previously unrecognized contributor to the neurotoxicity associated with HIV infection. PMID:22084248

  14. HIV-1 Vpr Induces Adipose Dysfunction in Vivo Through Reciprocal Effects on PPAR/GR Co-Regulation

    Science.gov (United States)

    Agarwal, Neeti; Iyer, Dinakar; Patel, Sanjeet G.; Sekhar, Rajagopal V.; Phillips, Terry M.; Schubert, Ulrich; Oplt, Toni; Buras, Eric D.; Samson, Susan L.; Couturier, Jacob; Lewis, Dorothy E.; Rodriguez-Barradas, Maria C.; Jahoor, Farook; Kino, Tomoshige; Kopp, Jeffrey B.; Balasubramanyam, Ashok

    2014-01-01

    Viral infections, such as HIV, have been linked to obesity, but mechanistic evidence that they cause adipose dysfunction in vivo is lacking. We investigated a pathogenic role for the HIV-1 accessory protein viral protein R (Vpr), which can coactivate the glucocorticoid receptor (GR) and co-repress peroxisome proliferator–activated receptor γ (PPARγ) in vitro, in HIV-associated adipose dysfunction. Vpr circulated in the blood of most HIV-infected patients tested, including those on antiretroviral therapy (ART) with undetectable viral load. Vpr-mediated mechanisms were dissected in vivo using mouse models expressing the Vpr transgene in adipose tissues and liver (Vpr-Tg) or infused with synthetic Vpr. Both models demonstrated accelerated whole-body lipolysis, hyperglycemia and hypertriglyceridemia, and tissue-specific findings. Fat depots in these mice had diminished mass, macrophage infiltration, and blunted PPARγ target gene expression but increased GR target gene expression. In liver, we observed blunted PPARα target gene expression, steatosis with decreased adenosine monophosphate– activated protein kinase activity, and insulin resistance. Similar to human HIV-infected patients, Vpr circulated in the serum of Vpr-Tg mice. Vpr blocked differentiation in preadipocytes through cell cycle arrest, whereas in mature adipocytes, it increased lipolysis with reciprocally altered association of PPARγ and GR with their target promoters. These results delineate a distinct pathogenic sequence: Vpr, released from HIV-1 in tissue reservoirs after ART, can disrupt PPAR/GR co-regulation and cell cycle control to produce adipose dysfunction and hepatosteatosis. Confirmation of these mechanisms in HIV patients could lead to targeted treatment of the metabolic complications with Vpr inhibitors, GR antagonists, or PPARγ/PPARα agonists. PMID:24285483

  15. Picomolar dichotomous activity of gnidimacrin against HIV-1.

    Directory of Open Access Journals (Sweden)

    Li Huang

    Full Text Available Highly active antiretroviral therapy (HAART has offered a promising approach for controlling HIV-1 replication in infected individuals. However, with HARRT, HIV-1 is suppressed rather than eradicated due to persistence of HIV-1 in latent viral reservoirs. Thus, purging the virus from latent reservoirs is an important strategy toward eradicating HIV-1 infection. In this study, we discovered that the daphnane diterpene gnidimacrin, which was previously reported to have potent anti-cancer cell activity, activated HIV-1 replication and killed persistently-infected cells at picomolar concentrations. In addition to its potential to purge HIV-1 from latently infected cells, gnidimacrin potently inhibited a panel of HIV-1 R5 virus infection of peripheral blood mononuclear cells (PBMCs at an average concentration lower than 10 pM. In contrast, gnidimacrin only partially inhibited HIV-1 ×4 virus infection of PBMCs. The strong anti-HIV-1 R5 virus activity of gnidimacrin was correlated with its effect on down-regulation of the HIV-1 coreceptor CCR5. The anti-R5 virus activity of gnidimacrin was completely abrogated by a selective protein kinase C beta inhibitor enzastaurin, which suggests that protein kinase C beta plays a key role in the potent anti-HIV-1 activity of gnidimacrin in PBMCs. In summary, these results suggest that gnidimacrin could activate latent HIV-1, specifically kill HIV-1 persistently infected cells, and inhibit R5 viruses at picomolar concentrations.

  16. GABBR1 has a HERV-W LTR in its regulatory region – a possible implication for schizophrenia

    Directory of Open Access Journals (Sweden)

    Hegyi Hedi

    2013-02-01

    Full Text Available Abstract Schizophrenia is a complex disease with uncertain aetiology. We suggest GABBR1, GABA receptor B1 implicated in schizophrenia based on a HERV-W LTR in the regulatory region of GABBR1. Our hypothesis is supported by: (i GABBR1 is in the 6p22 genomic region most often implicated in schizophrenia; (ii microarray studies found that only presynaptic pathway-related genes, including GABA receptors, have altered expression in schizophrenic patients and (iii it explains how HERV-W elements, expressed in schizophrenia, play a role in the disease: by altering the expression of GABBR1 via a long terminal repeat that is also a regulatory element to GABBR1. Reviewers This paper was reviewed by Sandor Pongor and Martijn Huynen.

  17. Intragenic HIV-1 env sequences that enhance gag expression

    International Nuclear Information System (INIS)

    Suptawiwat, Ornpreya; Sutthent, Ruengpung; Lee, T.-H.; Auewarakul, Prasert

    2003-01-01

    Expression of HIV-1 genes is regulated at multiple levels including the complex RNA splicing and transport mechanisms. Multiple cis-acting elements involved in these regulations have been previously identified in various regions of HIV-1 genome. Here we show that another cis-acting element was present in HIV-1 env region. This element enhanced the expression of Gag when inserted together with Rev response element (RRE) into a truncated HIV-1 genome in the presence of Rev. The enhancing activity was mapped to a 263-bp fragment in the gp41 region downstream to RRE. RNA analysis showed that it might function by promoting RNA stability and Rev-dependent RNA export. The enhancement was specific to Rev-dependent expression, since it did not enhance Gag expression driven by Sam68, a cellular protein that has been shown to be able to substitute for Rev in RNA export function

  18. LTR retrotransposon dynamics in the evolution of the olive (Olea europaea) genome

    Czech Academy of Sciences Publication Activity Database

    Barghini, E.; Natali, L.; Giordani, T.; Cossu, R.M.; Scalabrin, S.; Cattonaro, F.; Šimková, Hana; Vrána, Jan; Doležel, Jaroslav; Morgante, M.; Cavallini, A.

    2015-01-01

    Roč. 22, č. 1 (2015), s. 91-100 ISSN 1340-2838 R&D Projects: GA ČR GBP501/12/G090; GA MŠk(CZ) LO1204 Institutional support: RVO:61389030 Keywords : LTR retrotransposons * next-generation sequencing * olive Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 5.267, year: 2015

  19. The effects of 5-fluorouracil and doxorubicin on expression of human immunodeficiency virus type 1 long terminal repeat

    International Nuclear Information System (INIS)

    Panozzo, J.; Akan, E.; Griffiths, T.D.

    1996-01-01

    Previous work by many groups has documented induction of the HIV-LTR following exposure of cells to ultraviolet light and other DNA damaging agents. Our experiments set out to determine the relative activation or repression of the HIV-LTR in response to two classes of chemotherapeutic agents: Doxorubicin is a DNA-damage inducing agent, and 5-fluorouracil has an antimetabolic mode of action. Using HeLa cells stably transfected with a construct in which HIV-LTR drives expression of the chloramphenicol acetyl transferase reporter gene, we demonstrated an up to 10-fold induction following doxorubicin treatment in 24 h post-treatment. This induction was repressed by treatment with salicylic acid, suggesting a role for prostaglandin/cyclo-oxygenase pathways and/or NFKB in the inductive response. Induction by 5-fluorouracil, in contrast, was more modest (two-fold at most) though it was consistently elevated over controls

  20. Anti-HIV Antibody Responses and the HIV Reservoir Size during Antiretroviral Therapy.

    Directory of Open Access Journals (Sweden)

    Sulggi A Lee

    Full Text Available A major challenge to HIV eradication strategies is the lack of an accurate measurement of the total burden of replication-competent HIV (the "reservoir". We assessed the association of anti-HIV antibody responses and the estimated size of the reservoir during antiretroviral therapy (ART.We evaluated anti-HIV antibody profiles using luciferase immunoprecipitation systems (LIPS assay in relation to several blood-based HIV reservoir measures: total and 2-LTR DNA (rtPCR or droplet digital PCR; integrated DNA (Alu PCR; unspliced RNA (rtPCR, multiply-spliced RNA (TILDA, residual plasma HIV RNA (single copy PCR, and replication-competent virus (outgrowth assay. We also assessed total HIV DNA and RNA in gut-associated lymphoid tissue (rtPCR. Spearman correlations and linear regressions were performed using log-transformed blood- or tissue-based reservoir measurements as predictors and log-transformed antibody levels as outcome variables.Among 51 chronically HIV-infected ART-suppressed participants (median age = 57, nadir CD4+ count = 196 cells/mm3, ART duration = 9 years, the most statistically significant associations were between antibody responses to integrase and HIV RNA in gut-associated lymphoid tissue (1.17 fold-increase per two-fold RNA increase, P = 0.004 and between antibody responses to matrix and integrated HIV DNA in resting CD4+ T cells (0.35 fold-decrease per two-fold DNA increase, P = 0.003. However, these associations were not statistically significant after a stringent Bonferroni-adjustment of P<0.00045. Multivariate models including age and duration of ART did not markedly alter results.Our findings suggest that anti-HIV antibody responses may reflect the size of the HIV reservoir during chronic treated HIV disease, possibly via antigen recognition in reservoir sites. Larger, prospective studies are needed to validate the utility of antibody levels as a measure of the total body burden of HIV during treatment.

  1. HIV-1-infected macrophages induce astrogliosis by SDF-1α and matrix metalloproteinases

    International Nuclear Information System (INIS)

    Okamoto, Mika; Wang, Xin; Baba, Masanori

    2005-01-01

    Brain macrophages/microglia and astrocytes are known to be involved in the pathogenesis of HIV-1-associated dementia (HAD). To clarify their interaction and contribution to the pathogenesis, HIV-1-infected or uninfected macrophages were used as a model of brain macrophages/microglia, and their effects on human astrocytes in vitro were examined. The culture supernatants of HIV-1-infected or uninfected macrophages induced significant astrocyte proliferation, which was annihilated with a neutralizing antibody to stromal cell-derived factor (SDF)-1α or a matrix metalloproteinase (MMP) inhibitor. In these astrocytes, CXCR4, MMP, and tissue inhibitors of matrix metalloproteinase mRNA expression and SDF-1α production were significantly up-regulated. The supernatants of infected macrophages were always more effective than those of uninfected cells. Moreover, the enhanced production of SDF-1α was suppressed by the MMP inhibitor. These results indicate that the activated and HIV-1-infected macrophages can indirectly induce astrocyte proliferation through up-regulating SDF-1α and MMP production, which implies a mechanism of astrogliosis in HAD

  2. A yeast model for target-primed (non-LTR retrotransposition

    Directory of Open Access Journals (Sweden)

    Busby Jason N

    2007-08-01

    Full Text Available Abstract Background Target-primed (non-LTR retrotransposons, such as the human L1 element, are mobile genetic elements found in many eukaryotic genomes. They are often present in large numbers and their retrotransposition can cause mutations and genomic rearrangements. Despite their importance, many aspects of their replication are not well understood. Results We have developed a yeast model system for studying target-primed retrotransposons. This system uses the Zorro3 element from Candida albicans. A cloned copy of Zorro3, tagged with a retrotransposition indicator gene, retrotransposes at a high frequency when introduced into an appropriate C. albicans host strain. Retrotransposed copies of the tagged element exhibit similar features to the native copies, indicating that the natural retrotransposition pathway is being used. Retrotransposition is dependent on the products of the tagged element's own genes and is highly temperature-regulated. The new assay permits the analysis of the effects of specific mutations introduced into the cloned element. Conclusion This Zorro3 retrotransposition assay system complements previously available target-primed retrotransposition assays. Due to the relative simplicity of the growth, manipulation and analysis of yeast cells, the system should advance our understanding of target-primed retrotransposition.

  3. Chromatin Regulation and the Histone Code in HIV Latency
.

    Science.gov (United States)

    Turner, Anne-Marie W; Margolis, David M

    2017-06-01

    The formation of a latent reservoir of Human Immunodeficiency Virus (HIV) infection hidden from immune clearance remains a significant obstacle to approaches to eradicate HIV infection. Towards an understanding of the mechanisms of HIV persistence, there is a growing body of work implicating epigenetic regulation of chromatin in establishment and maintenance of this latent reservoir. Here we discuss recent advances in the field of chromatin regulation, specifically in our understanding of the histone code, and how these discoveries relate to our current knowledge of the chromatin mechanisms linked to HIV transcriptional repression and the reversal of latency. We also examine mechanisms unexplored in the context of HIV latency and briefly discuss current therapies aimed at the induction of proviral expression within latently infected cells. We aim to emphasize that a greater understanding of the epigenetic mechanisms which govern HIV latency could lead to new therapeutic targets for latency reversal and clearance cure strategies.

  4. A European multicientre study on the comparison of HIV-1 viral loads between VERIS HIV-1 Assay and Roche COBAS® TAQMAN® HIV-1 test, Abbott RealTime HIV-1 Assay, and Siemens VERSANT HIV-1 Assay.

    Science.gov (United States)

    Braun, Patrick; Delgado, Rafael; Drago, Monica; Fanti, Diana; Fleury, Hervé; Hofmann, Jörg; Izopet, Jacques; Kühn, Sebastian; Lombardi, Alessandra; Mancon, Alessandro; Marcos, Mª Angeles; Mileto, Davide; Sauné, Karine; O'Shea, Siobhan; Pérez-Rivilla, Alfredo; Ramble, John; Trimoulet, Pascale; Vila, Jordi; Whittaker, Duncan; Artus, Alain; Rhodes, Daniel

    2017-07-01

    Viral load monitoring is essential for patients under treatment for HIV. Beckman Coulter has developed the VERIS HIV-1 Assay for use on the novel, automated DxN VERIS Molecular Diagnostics System. ¥ OBJECTIVES: Evaluation of the clinical performance of the new quantitative VERIS HIV-1 Assay at multiple EU laboratories. Method comparison with the VERIS HIV-1 Assay was performed with 415 specimens at 5 sites tested with COBAS ® AmpliPrep/COBAS ® TaqMan ® HIV-1 Test, v2.0, 169 specimens at 3 sites tested with RealTime HIV-1 Assay, and 202 specimens from 2 sites tested with VERSANT HIV-1 Assay. Patient monitoring sample results from 4 sites were also compared. Bland-Altman analysis showed the average bias between VERIS HIV-1 Assay and COBAS HIV-1 Test, RealTime HIV-1 Assay, and VERSANT HIV-1 Assay to be 0.28, 0.39, and 0.61 log 10 cp/mL, respectively. Bias at low end levels below 1000cp/mL showed predicted bias to be <0.3 log 10 cp/mL for VERIS HIV-1 Assay versus COBAS HIV-1 Test and RealTime HIV-1 Assay, and <0.5 log 10 cp/mL versus VERSANT HIV-1 Assay. Analysis on 174 specimens tested with the 0.175mL volume VERIS HIV-1 Assay and COBAS HIV-1 Test showed average bias of 0.39 log 10 cp/mL. Patient monitoring results using VERIS HIV-1 Assay demonstrated similar viral load trends over time to all comparators. The VERIS HIV-1 Assay for use on the DxN VERIS System demonstrated comparable clinical performance to COBAS ® HIV-1 Test, RealTime HIV-1 Assay, and VERSANT HIV-1 Assay. Copyright © 2017 Elsevier B.V. All rights reserved.

  5. Isolation and characterization of a replication-competent molecular clone of an HIV-1 circulating recombinant form (CRF33_01B.

    Directory of Open Access Journals (Sweden)

    Kok Keng Tee

    Full Text Available A growing number of emerging HIV-1 recombinants classified as circulating recombinant forms (CRFs have been identified in Southeast Asia in recent years, establishing a molecular diversity of increasing complexity in the region. Here, we constructed a replication-competent HIV-1 clone for CRF33_01B (designated p05MYKL045.1, a newly identified recombinant comprised of CRF01_AE and subtype B. p05MYKL045.1 was reconstituted by cloning of the near full-length HIV-1 sequence from a newly-diagnosed individual presumably infected heterosexually in Kuala Lumpur, Malaysia. The chimeric clone, which contains the 5' LTR (long terminal repeat region of p93JP-NH1 (a previously isolated CRF01_AE infectious clone, showed robust viral replication in the human peripheral blood mononuclear cells. This clone demonstrated robust viral propagation and profound syncytium formation in CD4+, CXCR4-expressing human glioma NP-2 cells, indicating that p05MYKL045.1 is a CXCR4-using virus. Viral propagation, however, was not detected in various human T cell lines including MT-2, M8166, Sup-T1, H9, Jurkat, Molt-4 and PM1. p05MYKL045.1 appears to proliferate only in restricted host range, suggesting that unknown viral and/or cellular host factors may play a role in viral infectivity and replication in human T cell lines. Availability of a CRF33_01B molecular clone will be useful in facilitating the development of vaccine candidates that match the HIV-1 strains circulating in Southeast Asia.

  6. BET bromodomain inhibition as a novel strategy for reactivation of HIV-1.

    Science.gov (United States)

    Banerjee, Camellia; Archin, Nancie; Michaels, Daniel; Belkina, Anna C; Denis, Gerald V; Bradner, James; Sebastiani, Paola; Margolis, David M; Montano, Monty

    2012-12-01

    The persistence of latent HIV-1 remains a major challenge in therapeutic efforts to eradicate infection. We report the capacity for HIV reactivation by a selective small molecule inhibitor of BET family bromodomains, JQ1, a promising therapeutic agent with antioncogenic properties. JQ1 reactivated HIV transcription in models of latent T cell infection and latent monocyte infection. We also tested the effect of exposure to JQ1 to allow recovery of replication-competent HIV from pools of resting CD4(+) T cells isolated from HIV-infected, ART-treated patients. In one of three patients, JQ1 allowed recovery of virus at a frequency above unstimulated conditions. JQ1 potently suppressed T cell proliferation with minimal cytotoxic effect. Transcriptional profiling of T cells with JQ1 showed potent down-regulation of T cell activation genes, including CD3, CD28, and CXCR4, similar to HDAC inhibitors, but JQ1 also showed potent up-regulation of chromatin modification genes, including SIRT1, HDAC6, and multiple lysine demethylases (KDMs). Thus, JQ1 reactivates HIV-1 while suppressing T cell activation genes and up-regulating histone modification genes predicted to favor increased Tat activity. Thus, JQ1 may be useful in studies of potentially novel mechanisms for transcriptional control as well as in translational efforts to identify therapeutic molecules to achieve viral eradication.

  7. Glutamic Acid Residues in HIV-1 p6 Regulate Virus Budding and Membrane Association of Gag.

    Science.gov (United States)

    Friedrich, Melanie; Setz, Christian; Hahn, Friedrich; Matthaei, Alina; Fraedrich, Kirsten; Rauch, Pia; Henklein, Petra; Traxdorf, Maximilian; Fossen, Torgils; Schubert, Ulrich

    2016-04-25

    The HIV-1 Gag p6 protein regulates the final abscission step of nascent virions from the cell membrane by the action of its two late (L-) domains, which recruit Tsg101 and ALIX, components of the ESCRT system. Even though p6 consists of only 52 amino acids, it is encoded by one of the most polymorphic regions of the HIV-1 gag gene and undergoes various posttranslational modifications including sumoylation, ubiquitination, and phosphorylation. In addition, it mediates the incorporation of the HIV-1 accessory protein Vpr into budding virions. Despite its small size, p6 exhibits an unusually high charge density. In this study, we show that mutation of the conserved glutamic acids within p6 increases the membrane association of Pr55 Gag followed by enhanced polyubiquitination and MHC-I antigen presentation of Gag-derived epitopes, possibly due to prolonged exposure to membrane bound E3 ligases. The replication capacity of the total glutamic acid mutant E0A was almost completely impaired, which was accompanied by defective virus release that could not be rescued by ALIX overexpression. Altogether, our data indicate that the glutamic acids within p6 contribute to the late steps of viral replication and may contribute to the interaction of Gag with the plasma membrane.

  8. Alterations in the nuclear proteome of HIV-1 infected T-cells

    International Nuclear Information System (INIS)

    DeBoer, Jason; Jagadish, Teena; Haverland, Nicole A.; Madson, Christian J.; Ciborowski, Pawel; Belshan, Michael

    2014-01-01

    Virus infection of a cell involves the appropriation of host factors and the innate defensive response of the cell. The identification of proteins critical for virus replication may lead to the development of novel, cell-based inhibitors. In this study we mapped the changes in T-cell nuclei during human immunodeficiency virus type 1 (HIV-1) at 20 hpi. Using a stringent data threshold, a total of 13 and 38 unique proteins were identified in infected and uninfected cells, respectively, across all biological replicates. An additional 15 proteins were found to be differentially regulated between infected and control nuclei. STRING analysis identified four clusters of protein–protein interactions in the data set related to nuclear architecture, RNA regulation, cell division, and cell homeostasis. Immunoblot analysis confirmed the differential expression of several proteins in both C8166-45 and Jurkat E6-1 T-cells. These data provide a map of the response in host cell nuclei upon HIV-1 infection. - Highlights: • We identify changes in the expression of nuclear proteins during HIV-1 infection. • 163 nuclear proteins were found differentially regulated during HIV-1 infection. • Bioinformatic analysis identified several nuclear pathways altered by HIV infection. • Candidate factors were validated in two independent cell lines

  9. Alterations in the nuclear proteome of HIV-1 infected T-cells

    Energy Technology Data Exchange (ETDEWEB)

    DeBoer, Jason [Department of Medical Microbiology and Immunology, Creighton University, 2500 California Plaza, Omaha, NE 68178 (United States); Jagadish, Teena; Haverland, Nicole A. [Department of Pharmacology and Experimental Neuroscience, University of Nebraska Medical Center, Omaha, NE 68198 (United States); Madson, Christian J. [Department of Medical Microbiology and Immunology, Creighton University, 2500 California Plaza, Omaha, NE 68178 (United States); Ciborowski, Pawel [Department of Pharmacology and Experimental Neuroscience, University of Nebraska Medical Center, Omaha, NE 68198 (United States); The Nebraska Center for Virology, University of Nebraska, Lincoln 68583 (United States); Belshan, Michael, E-mail: michaelbelshan@creighton.edu [Department of Medical Microbiology and Immunology, Creighton University, 2500 California Plaza, Omaha, NE 68178 (United States); The Nebraska Center for Virology, University of Nebraska, Lincoln 68583 (United States)

    2014-11-15

    Virus infection of a cell involves the appropriation of host factors and the innate defensive response of the cell. The identification of proteins critical for virus replication may lead to the development of novel, cell-based inhibitors. In this study we mapped the changes in T-cell nuclei during human immunodeficiency virus type 1 (HIV-1) at 20 hpi. Using a stringent data threshold, a total of 13 and 38 unique proteins were identified in infected and uninfected cells, respectively, across all biological replicates. An additional 15 proteins were found to be differentially regulated between infected and control nuclei. STRING analysis identified four clusters of protein–protein interactions in the data set related to nuclear architecture, RNA regulation, cell division, and cell homeostasis. Immunoblot analysis confirmed the differential expression of several proteins in both C8166-45 and Jurkat E6-1 T-cells. These data provide a map of the response in host cell nuclei upon HIV-1 infection. - Highlights: • We identify changes in the expression of nuclear proteins during HIV-1 infection. • 163 nuclear proteins were found differentially regulated during HIV-1 infection. • Bioinformatic analysis identified several nuclear pathways altered by HIV infection. • Candidate factors were validated in two independent cell lines.

  10. The relationships between HIV stigma, emotional status, and emotional regulation among HIV-affected children in rural China.

    Science.gov (United States)

    Wei, Wei; Li, Xiaoming; Harrison, Sayward; Zhao, Junfeng; Zhao, Guoxiang

    2016-03-01

    Children affected by HIV/AIDS have unique psychosocial needs that often go unaddressed in traditional treatment approaches. They are more likely than unaffected peers to encounter stigma, including overt discriminatory behaviors, as well as stereotyped attitudes. In addition, HIV-affected children are at risk for experiencing negative affect, including sadness and depression. Previous studies have identified a link between HIV stigma and the subsequent emotional status of children affected by HIV/AIDS. However, limited data are available regarding protective psychological factors that can mitigate the effects of HIV stigma and thus promote resiliency for this vulnerable population. Utilizing data from 790 children aged 6-17 years affected by parental HIV in rural central China this study aims to examine the association between HIV stigma, including both enacted and perceived stigma, and emotional status among HIV-affected children, as well as to evaluate the mediating effects of emotional regulation on the relationship between HIV stigma and emotional status. In addition, the moderating role of age is tested. Multiple regression was conducted to test the mediation model. We found that the experience of HIV stigma had a direct positive effect on negative emotions among children affected by HIV. Emotional regulation offers a level of protection, as it mediated the impact of HIV stigma on negative emotions. Moreover, age was found to moderate the relationship between perceived stigma and negative emotions. A significant interaction between perceived stigma and age suggested that negative emotions increase with age among those who perceived a higher level of stigmatization. Results suggest that children affected by HIV may benefit from interventions designed to enhance their capacity to regulate emotions and that health professionals should be aware of the link between stigma and negative emotion in childhood and adolescence and use the knowledge to inform their

  11. SAMHD1 restricts HIV-1 replication and regulates interferon production in mouse myeloid cells.

    Directory of Open Access Journals (Sweden)

    Ruonan Zhang

    Full Text Available SAMHD1 restricts the replication of HIV-1 and other retroviruses in human myeloid and resting CD4(+ T cells and that is counteracted in SIV and HIV-2 by the Vpx accessory protein. The protein is a phosphohydrolase that lowers the concentration of deoxynucleoside triphosphates (dNTP, blocking reverse transcription of the viral RNA genome. Polymorphisms in the gene encoding SAMHD1 are associated with Aicardi-Goutières Syndrome, a neurological disorder characterized by increased type-I interferon production. SAMHD1 is conserved in mammals but its role in restricting virus replication and controlling interferon production in non-primate species is not well understood. We show that SAMHD1 is catalytically active and expressed at high levels in mouse spleen, lymph nodes, thymus and lung. siRNA knock-down of SAMHD1 in bone marrow-derived macrophages increased their susceptibility to HIV-1 infection. shRNA knock-down of SAMHD1 in the murine monocytic cell-line RAW264.7 increased its susceptibility to HIV-1 and murine leukemia virus and increased the levels of the dNTP pool. In addition, SAMHD1 knock-down in RAW264.7 cells induced the production of type-I interferon and several interferon-stimulated genes, modeling the situation in Aicardi-Goutières Syndrome. Our findings suggest that the role of SAMHD1 in restricting viruses is conserved in the mouse. The RAW264.7 cell-line serves as a useful tool to study the antiviral and innate immune response functions of SAMHD1.

  12. HIV-1-infected monocyte-derived dendritic cells do not undergo maturation but can elicit IL-10 production and T cell regulation

    Science.gov (United States)

    Granelli-Piperno, Angela; Golebiowska, Angelika; Trumpfheller, Christine; Siegal, Frederick P.; Steinman, Ralph M.

    2004-05-01

    Dendritic cells (DCs) undergo maturation during virus infection and thereby become potent stimulators of cell-mediated immunity. HIV-1 replicates in immature DCs, but we now find that infection is not accompanied by many components of maturation in either infected cells or uninfected bystanders. The infected cultures do not develop potent stimulating activity for the mixed leukocyte reaction (MLR), and the DCs producing HIV-1 gag p24 do not express CD83 and DC-lysosome-associated membrane protein maturation markers. If different maturation stimuli are applied to DCs infected with HIV-1, the infected cells selectively fail to mature. When DCs from HIV-1-infected patients are infected and cultured with autologous T cells, IL-10 was produced in 6 of 10 patients. These DC-T cell cocultures could suppress another immune response, the MLR. The regulation was partially IL-10-dependent and correlated in extent with the level of IL-10 produced. Suppressor cells only developed from infected patients, rather than healthy controls, and the DCs had to be exposed to live virus rather than HIV-1 gag peptides or protein. These results indicate that HIV-1-infected DCs have two previously unrecognized means to evade immune responses: maturation can be blocked reducing the efficacy of antigen presentation from infected cells, and T cell-dependent suppression can be induced.

  13. Gene Therapy for Fracture Repair

    Science.gov (United States)

    2007-05-01

    modulator-1; c-myc binding protein [ Homo sapiens ]. regulation of transcription, DNA dependent NM_012488 1.55 2.53 Rattus norvegicus α-2-macroglobulin...myc binding protein [ Homo sapiens ] Regulation of transcription, DNA dependent NM_012488 1.55 2.53 Rattus norvegicus α-2-macroglobulin (A2m) Protease...1-HIV LTR-MLV Promoter EG FP -C el l N um be r (M ea n) 10 ul Vector 50 ul Vector 7 Periosteal/Endosteal Cell Transduction 0 200 400 600 800

  14. Copy number variation of KIR genes influences HIV-1 control

    DEFF Research Database (Denmark)

    Pelak, Kimberly; Need, Anna C; Fellay, Jacques

    2011-01-01

    A genome-wide screen for large structural variants showed that a copy number variant (CNV) in the region encoding killer cell immunoglobulin-like receptors (KIR) associates with HIV-1 control as measured by plasma viral load at set point in individuals of European ancestry. This CNV encompasses...... the KIR3DL1-KIR3DS1 locus, encoding receptors that interact with specific HLA-Bw4 molecules to regulate the activation of lymphocyte subsets including natural killer (NK) cells. We quantified the number of copies of KIR3DS1 and KIR3DL1 in a large HIV-1 positive cohort, and showed that an increase in KIR3...... amounts of these activating and inhibitory KIR play a role in regulating the peripheral expansion of highly antiviral KIR3DS1+ NK cells, which may determine differences in HIV-1 control following infection....

  15. Interaction between HIV-1 Tat and DNA-PKcs modulates HIV transcription and class switch recombination.

    Science.gov (United States)

    Zhang, Shi-Meng; Zhang, He; Yang, Tian-Yi; Ying, Tian-Yi; Yang, Pei-Xiang; Liu, Xiao-Dan; Tang, Sheng-Jian; Zhou, Ping-Kun

    2014-01-01

    HIV-1 tat targets a variety of host cell proteins to facilitate viral transcription and disrupts host cellular immunity by inducing lymphocyte apoptosis, but whether it influences humoral immunity remains unclear. Previously, our group demonstrated that tat depresses expression of DNA-PKcs, a critical component of the non-homologous end joining pathway (NHEJ) of DNA double-strand breaks repair, immunoglobulin class switch recombination (CSR) and V(D)J recombination, and sensitizes cells to ionizing radiation. In this study, we demonstrated that HIV-1 Tat down-regulates DNA-PKcs expression by directly binding to the core promoter sequence. In addition, Tat interacts with and activates the kinase activity of DNA-PKcs in a dose-dependent and DNA independent manner. Furthermore, Tat inhibits class switch recombination (CSR) at low concentrations (≤ 4 µg/ml) and stimulates CSR at high concentrations (≥ 8 µg/ml). On the other hand, low protein level and high kinase activity of DNA-PKcs promotes HIV-1 transcription, while high protein level and low kinase activity inhibit HIV-1 transcription. Co-immunoprecipitation results revealed that DNA-PKcs forms a large complex comprised of Cyclin T1, CDK9 and Tat via direct interacting with CDK9 and Tat but not Cyclin T1. Taken together, our results provide new clues that Tat regulates host humoral immunity via both transcriptional depression and kinase activation of DNA-PKcs. We also raise the possibility that inhibitors and interventions directed towards DNA-PKcs may inhibit HIV-1 transcription in AIDS patients.

  16. HIV-1 transmission linkage in an HIV-1 prevention clinical trial

    Energy Technology Data Exchange (ETDEWEB)

    Leitner, Thomas [Los Alamos National Laboratory; Campbell, Mary S [UNIV OF WASHINGTON; Mullins, James I [UNIV OF WASHINGTON; Hughes, James P [UNIV OF WASHINGTON; Wong, Kim G [UNIV OF WASHINGTON; Raugi, Dana N [UNIV OF WASHINGTON; Scrensen, Stefanie [UNIV OF WASHINGTON

    2009-01-01

    HIV-1 sequencing has been used extensively in epidemiologic and forensic studies to investigate patterns of HIV-1 transmission. However, the criteria for establishing genetic linkage between HIV-1 strains in HIV-1 prevention trials have not been formalized. The Partners in Prevention HSV/HIV Transmission Study (ClinicaITrials.gov NCT00194519) enrolled 3408 HIV-1 serodiscordant heterosexual African couples to determine the efficacy of genital herpes suppression with acyclovir in reducing HIV-1 transmission. The trial analysis required laboratory confirmation of HIV-1 linkage between enrolled partners in couples in which seroconversion occurred. Here we describe the process and results from HIV-1 sequencing studies used to perform transmission linkage determination in this clinical trial. Consensus Sanger sequencing of env (C2-V3-C3) and gag (p17-p24) genes was performed on plasma HIV-1 RNA from both partners within 3 months of seroconversion; env single molecule or pyrosequencing was also performed in some cases. For linkage, we required monophyletic clustering between HIV-1 sequences in the transmitting and seroconverting partners, and developed a Bayesian algorithm using genetic distances to evaluate the posterior probability of linkage of participants sequences. Adjudicators classified transmissions as linked, unlinked, or indeterminate. Among 151 seroconversion events, we found 108 (71.5%) linked, 40 (26.5%) unlinked, and 3 (2.0%) to have indeterminate transmissions. Nine (8.3%) were linked by consensus gag sequencing only and 8 (7.4%) required deep sequencing of env. In this first use of HIV-1 sequencing to establish endpoints in a large clinical trial, more than one-fourth of transmissions were unlinked to the enrolled partner, illustrating the relevance of these methods in the design of future HIV-1 prevention trials in serodiscordant couples. A hierarchy of sequencing techniques, analysis methods, and expert adjudication contributed to the linkage

  17. Effects of As2O3 on DNA methylation, genomic instability, and LTR retrotransposon polymorphism in Zea mays.

    Science.gov (United States)

    Erturk, Filiz Aygun; Aydin, Murat; Sigmaz, Burcu; Taspinar, M Sinan; Arslan, Esra; Agar, Guleray; Yagci, Semra

    2015-12-01

    Arsenic is a well-known toxic substance on the living organisms. However, limited efforts have been made to study its DNA methylation, genomic instability, and long terminal repeat (LTR) retrotransposon polymorphism causing properties in different crops. In the present study, effects of As2O3 (arsenic trioxide) on LTR retrotransposon polymorphism and DNA methylation as well as DNA damage in Zea mays seedlings were investigated. The results showed that all of arsenic doses caused a decreasing genomic template stability (GTS) and an increasing Random Amplified Polymorphic DNAs (RAPDs) profile changes (DNA damage). In addition, increasing DNA methylation and LTR retrotransposon polymorphism characterized a model to explain the epigenetically changes in the gene expression were also found. The results of this experiment have clearly shown that arsenic has epigenetic effect as well as its genotoxic effect. Especially, the increasing of polymorphism of some LTR retrotransposon under arsenic stress may be a part of the defense system against the stress.

  18. Vorinostat positively regulates synaptic plasticity genes expression and spine density in HIV infected neurons: role of nicotine in progression of HIV-associated neurocognitive disorder

    Science.gov (United States)

    2014-01-01

    Background HIV-associated neurocognitive disorder (HAND) is characterized by development of cognitive, behavioral and motor abnormalities, and occurs in approximately 50% of HIV infected individuals. In the United States, the prevalence of cigarette smoking ranges from 35-70% in HIV-infected individuals compared to 20% in general population. Cognitive impairment in heavy cigarette smokers has been well reported. However, the synergistic effects of nicotine and HIV infection and the underlying mechanisms in the development of HAND are unknown. Results In this study, we explored the role of nicotine in the progression of HAND using SK-N-MC, a neuronal cell line. SK-N-MC cells were infected with HIV-1 in the presence or absence of nicotine for 7 days. We observed significant increase in HIV infectivity in SK-N-MC treated with nicotine compared to untreated HIV-infected neuronal cells. HIV and nicotine synergize to significantly dysregulate the expression of synaptic plasticity genes and spine density; with a concomitant increase of HDAC2 levels in SK-N-MC cells. In addition, inhibition of HDAC2 up-regulation with the use of vorinostat resulted in HIV latency breakdown and recovery of synaptic plasticity genes expression and spine density in nicotine/HIV alone and in co-treated SK-N-MC cells. Furthermore, increased eIF2 alpha phosphorylation, which negatively regulates eukaryotic translational process, was observed in HIV alone and in co-treatment with nicotine compared to untreated control and nicotine alone treated SK-N-MC cells. Conclusions These results suggest that nicotine and HIV synergize to negatively regulate the synaptic plasticity gene expression and spine density and this may contribute to the increased risk of HAND in HIV infected smokers. Apart from disrupting latency, vorinostat may be a useful therapeutic to inhibit the negative regulatory effects on synaptic plasticity in HIV infected nicotine abusers. PMID:24886748

  19. Quantitative analysis of differentially expressed saliva proteins in human immunodeficiency virus type 1 (HIV-1) infected individuals

    International Nuclear Information System (INIS)

    Zhang, Nawei; Zhang, Zhenyu; Feng, Shan; Wang, Qingtao; Malamud, Daniel; Deng, Haiteng

    2013-01-01

    Highlights: ► A high-throughput method for profiling and quantification of the differentially expressed proteins in saliva samples was developed. ► Identified that DMBT1, S100A7, S100A8, S100A9 and alpha defensin were up-regulated in saliva from HIV-1 seropositive patients. ► Established analytical strategies are translatable to the clinical setting. -- Abstract: In the present study, we have established a new methodology to analyze saliva proteins from HIV-1-seropositive patients before highly active antiretroviral therapy (HAART) and seronegative controls. A total of 593 and 601 proteins were identified in the pooled saliva samples from 5 HIV-1 subjects and 5 controls, respectively. Forty-one proteins were found to be differentially expressed. Bioinformatic analysis of differentially expressed salivary proteins showed an increase of antimicrobial proteins and decrease of protease inhibitors upon HIV-1 infection. To validate some of these differentially expressed proteins, a high-throughput quantitation method was established to determine concentrations of 10 salivary proteins in 40 individual saliva samples from 20 seropositive patients before HAART and 20 seronegative subjects. This method was based on limited protein separation within the zone of the stacking gel of the 1D SDS PAGE and using isotope-coded synthetic peptides as internal standards. The results demonstrated that a combination of protein profiling and targeted quantitation is an efficient method to identify and validate differentially expressed salivary proteins. Expression levels of members of the calcium-binding S100 protein family and deleted in malignant brain tumors 1 protein (DMBT1) were up-regulated while that of Mucin 5B was down-regulated in HIV-1 seropositive saliva samples, which may provide new perspectives for monitoring HIV-infection and understanding the mechanism of HIV-1 infectivity

  20. Quantitative analysis of differentially expressed saliva proteins in human immunodeficiency virus type 1 (HIV-1) infected individuals

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Nawei; Zhang, Zhenyu [Beijing Chaoyang Hospital Affiliated Capital Medical University, Beijing (China); Feng, Shan [MOE Key Laboratory of Bioinformatics, School of Life Sciences, Tsinghua University, Beijing (China); Wang, Qingtao [Beijing Chaoyang Hospital Affiliated Capital Medical University, Beijing (China); Malamud, Daniel [NYU College of Dentistry, 345 East 24th Street, New York, NY 10010 (United States); Deng, Haiteng, E-mail: dht@mail.tsinghua.edu.cn [MOE Key Laboratory of Bioinformatics, School of Life Sciences, Tsinghua University, Beijing (China)

    2013-04-24

    Highlights: ► A high-throughput method for profiling and quantification of the differentially expressed proteins in saliva samples was developed. ► Identified that DMBT1, S100A7, S100A8, S100A9 and alpha defensin were up-regulated in saliva from HIV-1 seropositive patients. ► Established analytical strategies are translatable to the clinical setting. -- Abstract: In the present study, we have established a new methodology to analyze saliva proteins from HIV-1-seropositive patients before highly active antiretroviral therapy (HAART) and seronegative controls. A total of 593 and 601 proteins were identified in the pooled saliva samples from 5 HIV-1 subjects and 5 controls, respectively. Forty-one proteins were found to be differentially expressed. Bioinformatic analysis of differentially expressed salivary proteins showed an increase of antimicrobial proteins and decrease of protease inhibitors upon HIV-1 infection. To validate some of these differentially expressed proteins, a high-throughput quantitation method was established to determine concentrations of 10 salivary proteins in 40 individual saliva samples from 20 seropositive patients before HAART and 20 seronegative subjects. This method was based on limited protein separation within the zone of the stacking gel of the 1D SDS PAGE and using isotope-coded synthetic peptides as internal standards. The results demonstrated that a combination of protein profiling and targeted quantitation is an efficient method to identify and validate differentially expressed salivary proteins. Expression levels of members of the calcium-binding S100 protein family and deleted in malignant brain tumors 1 protein (DMBT1) were up-regulated while that of Mucin 5B was down-regulated in HIV-1 seropositive saliva samples, which may provide new perspectives for monitoring HIV-infection and understanding the mechanism of HIV-1 infectivity.

  1. Effects of gamma rays, ultraviolet radiation, sunlight, microwaves and electromagnetic fields on gene expression mediated by human immunodeficiency virus promoter

    International Nuclear Information System (INIS)

    Libertin, C.R.; Woloschak, G.E.; Panozzo, J.; Groh, K.R.; Chang-Liu, Chin-Mei; Schreck, S.

    1994-01-01

    Previous work by our group and others has shown the modulation of human immunodeficiency virus (HIV) promoter or long terminal repeat (LTR) after exposure to neutrons and ultraviolet radiations. Using HeLa cells stably transfected with a construct containing the chloramphenicol acetyl transferase (CAT) gene, the transcription of which is mediated by the HIV-LTR, we designed experiments to examine the effects of exposure to different types of radiation (such as γ rays, ultraviolet and sunlight irradiations, electromagnetic fields and microwaves) in HIV-LTR-driven expression of CAT. These results demonstrated ultraviolet-light-induced transcription from the HIV promoter, as has been shown by others. Exposure to other DNA-damaging agents such as γ rays and sunlight (with limited exposures) had no significant effect on transcription mediated by HIV-LTR, suggesting that induction of HIV is not mediated by just any type of DNA damage but rather may require specific types of DNA damage. Microwaves did not cause cell killing when cells in culture were exposed in high volumes of medium, and the same cells showed no changes in expression. When microwave exposure was carried out in low volumes of medium (so that excessive heat was generated) induction of HIV-LTR transcription (as assayed by CAT activity) was evident. Electromagnetic field exposures had no effect on expression of HIV-LTR. These results demonstrate that not all types of radiation and not all DNA-damaging agents are capable of inducing HIV. We hypothesize that induction of HIV transcription may be mediated by several different signals exposure to radiation. 22 refs., 8 figs

  2. A specific insertion of a solo-LTR characterizes the Y-chromosome of Bryonia dioica (Cucurbitaceae).

    Science.gov (United States)

    Oyama, Ryan K; Silber, Martina V; Renner, Susanne S

    2010-06-14

    Relatively few species of flowering plants are dioecious and even fewer are known to have sex chromosomes. Current theory posits that homomorphic sex chromosomes, such as found in Bryonia dioica (Cucurbitaceae), offer insight into the early stages in the evolution of sex chromosomes from autosomes. Little is known about these early steps, but an accumulation of transposable element sequences has been observed on the Y-chromosomes of some species with heteromorphic sex chromosomes. Recombination, by which transposable elements are removed, is suppressed on at least part of the emerging Y-chromosome, and this may explain the correlation between the emergence of sex chromosomes and transposable element enrichment. We sequenced 2321 bp of the Y-chromosome in Bryonia dioica that flank a male-linked marker, BdY1, reported previously. Within this region, which should be suppressed for recombination, we observed a solo-LTR nested in a Copia-like transposable element. We also found other, presumably paralogous, solo-LTRs in a consensus sequence of the underlying Copia-like transposable element. Given that solo-LTRs arise via recombination events, it is noteworthy that we find one in a genomic region where recombination should be suppressed. Although the solo-LTR could have arisen before recombination was suppressed, creating the male-linked marker BdY1, our previous study on B. dioica suggested that BdY1 may not lie in the recombination-suppressed region of the Y-chromosome in all populations. Presence of a solo-LTR near BdY1 therefore fits with the observed correlation between retrotransposon accumulation and the suppression of recombination early in the evolution of sex chromosomes. These findings further suggest that the homomorphic sex chromosomes of B. dioica, the first organism for which genetic XY sex-determination was inferred, are evolutionarily young and offer reference information for comparative studies of other plant sex chromosomes.

  3. HIV-1 Nef binds with human GCC185 protein and regulates mannose 6 phosphate receptor recycling

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, Manjeet; Kaur, Supinder; Nazir, Aamir; Tripathi, Raj Kamal, E-mail: rajkamalcdri@gmail.com

    2016-05-20

    HIV-1 Nef modulates cellular function that enhances viral replication in vivo which culminate into AIDS pathogenesis. With no enzymatic activity, Nef regulates cellular function through host protein interaction. Interestingly, trans-cellular introduction of recombinant Nef protein in Caenorhabditis elegans results in AIDS like pathogenesis which might share common pathophysiology because the gene sequence of C. elegans and humans share considerable homology. Therefore employing C. elegans based initial screen complemented with sequence based homology search we identified GCC185 as novel host protein interacting with HIV-1 Nef. The detailed molecular characterization revealed N-terminal EEEE{sub 65} acidic domain of Nef as key region for interaction. GCC185 is a tethering protein that binds with Rab9 transport vesicles. Our results show that Nef-GCC185 interaction disrupts Rab9 interaction resulting in delocalization of CI-MPR (cation independent Mannose 6 phosphate receptor) resulting in elevated secretion of hexosaminidase. In agreement with this, our studies identified novel host GCC185 protein that interacts with Nef EEEE65 acidic domain interfering GCC185-Rab9 vesicle membrane fusion responsible for retrograde vesicular transport of CI-MPR from late endosomes to TGN. In light of existing report suggesting critical role of Nef-GCC185 interaction reveals valuable mechanistic insights affecting specific protein transport pathway in docking of late endosome derived Rab9 bearing transport vesicle at TGN elucidating role of Nef during viral pathogenesis. -- Highlights: •Nef, an accessory protein of HIV-1 interacts with host factor and culminates into AIDS pathogenesis. •Using Caenorhabditis elegans based screen system, novel Nef interacting cellular protein GCC185 was identified. •Molecular characterization of Nef and human protein GCC185 revealed Nef EEEE{sub 65} key region interacted with full length GCC185. •Nef impeded the GCC185-Rab 9 interaction and

  4. Clinical presentation and opportunistic infections in HIV-1, HIV-2 and HIV-1/2 dual seropositive patients in Guinea-Bissau

    DEFF Research Database (Denmark)

    Sørensen, Allan; Jespersen, Sanne; Katzenstein, Terese L

    2016-01-01

    HIV-2 is prevalent. In this study, we aimed to characterize the clinical presentations among HIV-1, HIV-2 and HIV-1/2 dual seropositive patients. Methods: In a cross-sectional study, newly diagnosed HIV patients attending the HIV outpatient clinic at Hospital Nacional Sim~ao Mendes in Guinea......-Bissau were enrolled. Demographical and clinical data were collected and compared between HIV-1, HIV-2 and HIV-1/2 dual seropositive patients. Results: A total of 169 patients (76% HIV-1, 17% HIV-2 and 6% HIV 1/2) were included in the study between 21 March 2012 and 14 December 2012. HIV-1 seropositive...... antigen. Conclusion: HIV-1 and HIV-1/2 seropositive patients have lower CD4 cell counts than HIV-2 seropositive patients when diagnosed with HIV with only minor clinical and demographic differences among groups. Few patients were diagnosed with TB and cryptococcal disease was not found to be a major...

  5. Enhancement of Intranasal Vaccination in Mice with Deglycosylated Chain A Ricin by LTR72, a Novel Mucosal Adjuvant

    National Research Council Canada - National Science Library

    Kende, Meir; Del Giudice, Giuseppe; Rivera, Noelia; Hewetson, John

    2006-01-01

    .... However, in the presence of 4, 2, or 1 microg of the mucosal adjuvant LTR72, a mutant of the heat-labile enterotoxin of Escherichia coli, the low antibody response and protection were substantially enhanced...

  6. Chemical Composition of Essential Oils from Thymus vulgaris, Cymbopogon citratus, and Rosmarinus officinalis, and Their Effects on the HIV-1 Tat Protein Function.

    Science.gov (United States)

    Feriotto, Giordana; Marchetti, Nicola; Costa, Valentina; Beninati, Simone; Tagliati, Federico; Mischiati, Carlo

    2018-02-01

    New drugs would be beneficial to fight resistant HIV strains, in particular those capable of interfering with essential viral functions other than those targeted by highly active antiretroviral therapy drugs. Despite the central role played by Tat protein in HIV transcription, a search for vegetable extracts able to hamper this important viral function was never carried out. In this work, we evaluated the chemical composition and possible interference of essential oil from Thymus vulgaris, Cananga odorata, Cymbopogon citratus, and Rosmarinus officinalis with the Tat/TAR-RNA interaction and with Tat-induced HIV-1 LTR transcription. GC/MS Analysis demonstrated the biodiversity of herbal species translated into essential oils composed of different blends of terpenes. In all of them, 4 - 6 constituents represent from 81.63% to 95.19% of the total terpenes. Essential oils of Thymus vulgaris, Cymbopogon citratus, and Rosmarinus officinalis were active in interfering with Tat functions, encouraging further studies to identify single terpenes responsible for the antiviral activity. In view of the quite different composition of these essential oils, we concluded that their interference on Tat function depends on specific terpene or a characteristic blend. © 2018 Wiley-VHCA AG, Zurich, Switzerland.

  7. μ-opioid modulation of HIV-1 coreceptor expressionand HIV-1 replication

    International Nuclear Information System (INIS)

    Steele, Amber D.; Henderson, Earl E.; Rogers, Thomas J.

    2003-01-01

    A substantial proportion of HIV-1-infected individuals are intravenous drug users (IVDUs) who abuse opiates. Opioids induce a number of immunomodulatory effects that may directly influence HIV-1 disease progression. In the present report, we have investigated the effect of opioids on the expression of the major HIV-1 coreceptors CXCR4 and CCR5. For these studies we have focused on opiates which are ligands for the μ-opioid receptor. Our results show that DAMGO, a selective μ-opioid agonist, increases CXCR4 and CCR5 expression in both CD3 + lymphoblasts and CD14 + monocytes three- to fivefold. Furthermore, DAMGO-induced elevation of HIV-1 coreceptor expression translates into enhanced replication of both X4 and R5 viral strains of HIV-1. We have confirmed the role of the μ-opioid receptor based on the ability of a μ-opioid receptor-selective antagonist to block the effects of DAMGO. We have also found that morphine enhances CXCR4 and CCR5 expression and subsequently increases both X4 and R5 HIV-1 infection. We suggest that the capacity of μ-opioids to increase HIV-1 coreceptor expression and replication may promote viral binding, trafficking of HIV-1-infected cells, and enhanced disease progression

  8. HIV-1 incorporates and proteolytically processes human NDR1 and NDR2 serine-threonine kinases

    International Nuclear Information System (INIS)

    Devroe, Eric; Silver, Pamela A.; Engelman, Alan

    2005-01-01

    Mammalian genomes encode two related serine-threonine kinases, nuclear Dbf2 related (NDR)1 and NDR2, which are homologous to the Saccharomyces cerevisiae Dbf2 kinase. Recently, a yeast genetic screen implicated the Dbf2 kinase in Ty1 retrotransposition. Since several virion-incorporated kinases regulate the infectivity of human immunodeficiency virus type 1 (HIV-1), we speculated that the human NDR1 and NDR2 kinases might play a role in the HIV-1 life cycle. Here we show that the NDR1 and NDR2 kinases were incorporated into HIV-1 particles. Furthermore, NDR1 and NDR2 were cleaved by the HIV-1 protease (PR), both within virions and within producer cells. Truncation at the PR cleavage site altered NDR2 subcellular localization and inhibited NDR1 and NDR2 enzymatic activity. These studies identify two new virion-associated host cell enzymes and suggest a novel mechanism by which HIV-1 alters the intracellular environment of human cells

  9. Enhancement of Intranasal Vaccination in Mice with Deglycosylated Chain A Ricin by LTR72, a Novel Mucosal Adjuvant

    National Research Council Canada - National Science Library

    Kende, Meir; Del Giudice, Giuseppe; Rivera, Noelia; Hewetson, John

    2006-01-01

    .... However, in the presence of 4, 2, or 1 micro-gram of the mucosal adjuvant LTR72, a mutant of the heat-labile enterotoxin of Escherichia coli, the low antibody response and protection were substantially enhanced...

  10. Comparative Methylation of ERVWE1/Syncytin-1 and Other Human Endogenous Retrovirus LTRs in Placenta Tissues

    Science.gov (United States)

    Gimenez, Juliette; Montgiraud, Cécile; Oriol, Guy; Pichon, Jean-Philippe; Ruel, Karine; Tsatsaris, Vassilis; Gerbaud, Pascale; Frendo, Jean-Louis; Evain-Brion, Danièle; Mallet, François

    2009-01-01

    Human endogenous retroviruses (HERVs) are globally silent in somatic cells. However, some HERVs display high transcription in physiological conditions. In particular, ERVWE1, ERVFRDE1 and ERV3, three proviruses of distinct families, are highly transcribed in placenta and produce envelope proteins associated with placenta development. As silencing of repeated elements is thought to occur mainly by DNA methylation, we compared the methylation of ERVWE1 and related HERVs to appreciate whether HERV methylation relies upon the family, the integration site, the tissue, the long terminal repeat (LTR) function or the associated gene function. CpG methylation of HERV-W LTRs in placenta-associated tissues was heterogeneous but a joint epigenetic control was found for ERVWE1 5′LTR and its juxtaposed enhancer, a mammalian apparent LTR retrotransposon. Additionally, ERVWE1, ERVFRDE1 and ERV3 5′LTRs were all essentially hypomethylated in cytotrophoblasts during pregnancy, but showed distinct and stage-dependent methylation profiles. In non-cytotrophoblastic cells, they also exhibited different methylation profiles, compatible with their respective transcriptional activities. Comparative analyses of transcriptional activity and LTR methylation in cell lines further sustained a role for methylation in the control of functional LTRs. These results suggest that HERV methylation might not be family related but copy-specific, and related to the LTR function and the tissue. In particular, ERVWE1 and ERV3 could be developmentally epigenetically regulated HERVs. PMID:19561344

  11. HIV-1 stimulates nuclear entry of amyloid beta via dynamin dependent EEA1 and TGF-β/Smad signaling

    International Nuclear Information System (INIS)

    András, Ibolya E.; Toborek, Michal

    2014-01-01

    Clinical evidence indicates increased amyloid deposition in HIV-1-infected brains, which contributes to neurocognitive dysfunction in infected patients. Here we show that HIV-1 exposure stimulates amyloid beta (Aβ) nuclear entry in human brain endothelial cells (HBMEC), the main component of the blood–brain barrier (BBB). Treatment with HIV-1 and/or Aβ resulted in concurrent increase in early endosomal antigen-1 (EEA1), Smad, and phosphorylated Smad (pSmad) in nuclear fraction of HBMEC. A series of inhibition and silencing studies indicated that Smad and EEA1 closely interact by influencing their own nuclear entry; the effect that was attenuated by dynasore, a blocker of GTP-ase activity of dynamin. Importantly, inhibition of dynamin, EEA1, or TGF-β/Smad effectively attenuated HIV-1-induced Aβ accumulation in the nuclei of HBMEC. The present study indicates that nuclear uptake of Aβ involves the dynamin-dependent EEA1 and TGF-β/Smad signaling pathways. These results identify potential novel targets to protect against HIV-1-associated dysregulation of amyloid processes at the BBB level. - Highlights: • HIV-1 induces nuclear accumulation of amyloid beta (Aβ) in brain endothelial cells. • EEA-1 and TGF-Β/Smad act in concert to regulate nuclear entry of Aβ. • Dynamin appropriates the EEA-1 and TGF-Β/Smad signaling. • Dynamin serves as a master regulator of HIV-1-induced nuclear accumulation of Aβ

  12. HIV-1 stimulates nuclear entry of amyloid beta via dynamin dependent EEA1 and TGF-β/Smad signaling

    Energy Technology Data Exchange (ETDEWEB)

    András, Ibolya E., E-mail: iandras@med.miami; Toborek, Michal, E-mail: mtoborek@med.miami.edu

    2014-04-15

    Clinical evidence indicates increased amyloid deposition in HIV-1-infected brains, which contributes to neurocognitive dysfunction in infected patients. Here we show that HIV-1 exposure stimulates amyloid beta (Aβ) nuclear entry in human brain endothelial cells (HBMEC), the main component of the blood–brain barrier (BBB). Treatment with HIV-1 and/or Aβ resulted in concurrent increase in early endosomal antigen-1 (EEA1), Smad, and phosphorylated Smad (pSmad) in nuclear fraction of HBMEC. A series of inhibition and silencing studies indicated that Smad and EEA1 closely interact by influencing their own nuclear entry; the effect that was attenuated by dynasore, a blocker of GTP-ase activity of dynamin. Importantly, inhibition of dynamin, EEA1, or TGF-β/Smad effectively attenuated HIV-1-induced Aβ accumulation in the nuclei of HBMEC. The present study indicates that nuclear uptake of Aβ involves the dynamin-dependent EEA1 and TGF-β/Smad signaling pathways. These results identify potential novel targets to protect against HIV-1-associated dysregulation of amyloid processes at the BBB level. - Highlights: • HIV-1 induces nuclear accumulation of amyloid beta (Aβ) in brain endothelial cells. • EEA-1 and TGF-Β/Smad act in concert to regulate nuclear entry of Aβ. • Dynamin appropriates the EEA-1 and TGF-Β/Smad signaling. • Dynamin serves as a master regulator of HIV-1-induced nuclear accumulation of Aβ.

  13. Immune defence against HIV-1 infection in HIV-1-exposed seronegative persons.

    Science.gov (United States)

    Schmechel, S C; Russell, N; Hladik, F; Lang, J; Wilson, A; Ha, R; Desbien, A; McElrath, M J

    2001-11-01

    Rare individuals who are repeatedly exposed to HIV-1 through unprotected sexual contact fail to acquire HIV-1 infection. These persons represent a unique study population to evaluate mechanisms by which HIV-1 replication is either prevented or controlled. We followed longitudinally a group of healthy HIV-1 seronegative persons each reporting repeated high-risk sexual activities with their HIV-1-infected partner at enrollment. The volunteers were primarily (90%) male homosexuals, maintaining high risk activities with their known infected partner (45%) or multiple other partners (61%). We evaluated the quantity and specificity of HIV-1-specific T cells in 31 exposed seronegatives (ES) using a IFN-gamma ELISPOT assay to enumerate T cells recognizing epitopes within HIV-1 Env, Gag, Pol and Nef. PBMC from only three of the 31 volunteers demonstrated ex vivo HIV-1-specific IFN-gamma secretion, in contrast to nearly 30% exhibiting cytolytic responses in previous studies. These findings suggest that if T cell responses in ES are induced by HIV-1 exposure, the frequency is at low levels in most of them, and below the level of detection using the ELISPOT assay. Alternative approaches to improve the sensitivity of detection may include use of dendritic cells as antigen-presenting cells in the ex vivo assay and more careful definition of the risk behavior and extent of HIV-1 exposure in conjunction with the evaluation of T cell responses.

  14. HIV-1 infection induces changes in expression of cellular splicing factors that regulate alternative viral splicing and virus production in macrophages

    Directory of Open Access Journals (Sweden)

    Purcell Damian FJ

    2008-02-01

    Full Text Available Abstract Background Macrophages are important targets and long-lived reservoirs of HIV-1, which are not cleared of infection by currently available treatments. In the primary monocyte-derived macrophage model of infection, replication is initially productive followed by a decline in virion output over ensuing weeks, coincident with a decrease in the levels of the essential viral transactivator protein Tat. We investigated two possible mechanisms in macrophages for regulation of viral replication, which appears to be primarily regulated at the level of tat mRNA: 1 differential mRNA stability, used by cells and some viruses for the rapid regulation of gene expression and 2 control of HIV-1 alternative splicing, which is essential for optimal viral replication. Results Following termination of transcription at increasing times after infection in macrophages, we found that tat mRNA did indeed decay more rapidly than rev or nef mRNA, but with similar kinetics throughout infection. In addition, tat mRNA decayed at least as rapidly in peripheral blood lymphocytes. Expression of cellular splicing factors in uninfected and infected macrophage cultures from the same donor showed an inverse pattern over time between enhancing factors (members of the SR family of RNA binding proteins and inhibitory factors (members of the hnRNP family. While levels of the SR protein SC35 were greatly up-regulated in the first week or two after infection, hnRNPs of the A/B and H groups were down-regulated. Around the peak of virus production in each culture, SC35 expression declined to levels in uninfected cells or lower, while the hnRNPs increased to control levels or above. We also found evidence for increased cytoplasmic expression of SC35 following long-term infection. Conclusion While no evidence of differential regulation of tat mRNA decay was found in macrophages following HIV-1 infection, changes in the balance of cellular splicing factors which regulate alternative

  15. Genome-wide analysis of LTR-retrotransposons in oil palm.

    Science.gov (United States)

    Beulé, Thierry; Agbessi, Mawussé Dt; Dussert, Stephane; Jaligot, Estelle; Guyot, Romain

    2015-10-15

    The oil palm (Elaeis guineensis Jacq.) is a major cultivated crop and the world's largest source of edible vegetable oil. The genus Elaeis comprises two species E. guineensis, the commercial African oil palm and E. oleifera, which is used in oil palm genetic breeding. The recent publication of both the African oil palm genome assembly and the first draft sequence of its Latin American relative now allows us to tackle the challenge of understanding the genome composition, structure and evolution of these palm genomes through the annotation of their repeated sequences. In this study, we identified, annotated and compared Transposable Elements (TE) from the African and Latin American oil palms. In a first step, Transposable Element databases were built through de novo detection in both genome sequences then the TE content of both genomes was estimated. Then putative full-length retrotransposons with Long Terminal Repeats (LTRs) were further identified in the E. guineensis genome for characterization of their structural diversity, copy number and chromosomal distribution. Finally, their relative expression in several tissues was determined through in silico analysis of publicly available transcriptome data. Our results reveal a congruence in the transpositional history of LTR retrotransposons between E. oleifera and E. guineensis, especially the Sto-4 family. Also, we have identified and described 583 full-length LTR-retrotransposons in the Elaeis guineensis genome. Our work shows that these elements are most likely no longer mobile and that no recent insertion event has occurred. Moreover, the analysis of chromosomal distribution suggests a preferential insertion of Copia elements in gene-rich regions, whereas Gypsy elements appear to be evenly distributed throughout the genome. Considering the high proportion of LTR retrotransposon in the oil palm genome, our work will contribute to a greater understanding of their impact on genome organization and evolution

  16. Transcriptional profiling reveals molecular signatures associated with HIV permissiveness in Th1Th17 cells and identifies Peroxisome Proliferator-Activated Receptor Gamma as an intrinsic negative regulator of viral replication

    Science.gov (United States)

    2013-01-01

    Background We previously demonstrated that primary Th1Th17 cells are highly permissive to HIV-1, whereas Th1 cells are relatively resistant. Molecular mechanisms underlying these differences remain unknown. Results Exposure to replication competent and single-round VSV-G pseudotyped HIV strains provide evidence that superior HIV replication in Th1Th17 vs. Th1 cells was regulated by mechanisms located at entry and post-entry levels. Genome-wide transcriptional profiling identified transcripts upregulated (n = 264) and downregulated (n = 235) in Th1Th17 vs. Th1 cells (p-value Th17 (nuclear receptors, trafficking, p38/MAPK, NF-κB, p53/Ras, IL-23) vs. Th1 cells (proteasome, interferon α/β). Differentially expressed genes were classified into biological categories using Gene Ontology. Th1Th17 cells expressed typical Th17 markers (IL-17A/F, IL-22, CCL20, RORC, IL-26, IL-23R, CCR6) and transcripts functionally linked to regulating cell trafficking (CEACAM1, MCAM), activation (CD28, CD40LG, TNFSF13B, TNFSF25, PTPN13, MAP3K4, LTB, CTSH), transcription (PPARγ, RUNX1, ATF5, ARNTL), apoptosis (FASLG), and HIV infection (CXCR6, FURIN). Differential expression of CXCR6, PPARγ, ARNTL, PTPN13, MAP3K4, CTSH, SERPINB6, PTK2, and ISG20 was validated by RT-PCR, flow cytometry and/or confocal microscopy. The nuclear receptor PPARγ was preferentially expressed by Th1Th17 cells. PPARγ RNA interference significantly increased HIV replication at levels post-entry and prior HIV-DNA integration. Finally, the activation of PPARγ pathway via the agonist Rosiglitazone induced the nuclear translocation of PPARγ and a robust inhibition of viral replication. Conclusions Thus, transcriptional profiling in Th1Th17 vs. Th1 cells demonstrated that HIV permissiveness is associated with a superior state of cellular activation and limited antiviral properties and identified PPARγ as an intrinsic negative regulator of viral replication. Therefore, triggering PPARγ pathway via non

  17. Iron chelators ICL670 and 311 inhibit HIV-1 transcription

    International Nuclear Information System (INIS)

    Debebe, Zufan; Ammosova, Tatyana; Jerebtsova, Marina; Kurantsin-Mills, Joseph; Niu, Xiaomei; Charles, Sharroya; Richardson, Des R.; Ray, Patricio E.; Gordeuk, Victor R.; Nekhai, Sergei

    2007-01-01

    HIV-1 replication is induced by an excess of iron and iron chelation by desferrioxamine (DFO) inhibits viral replication by reducing proliferation of infected cells. Treatment of cells with DFO and 2-hydroxy-1-naphthylaldehyde isonicotinoyl hydrazone (311) inhibit expression of proteins that regulate cell-cycle progression, including cycle-dependent kinase 2 (CDK2). Our recent studies showed that CDK2 participates in HIV-1 transcription and viral replication suggesting that inhibition of CDK2 by iron chelators might also affect HIV-1 transcription. Here we evaluated the effect of a clinically approved orally effective iron chelator, 4-[3,5-bis-(hydroxyphenyl)-1,2,4-triazol-1-yl]-benzoic acid (ICL670) and 311 on HIV-1 transcription. Both ICL670 and 311 inhibited Tat-induced HIV-1 transcription in CEM-T cells, 293T and HeLa cells. Neither ICL670 nor 311 induced cytotoxicity at concentrations that inhibited HIV-1 transcription. The chelators decreased cellular activity of CDK2 and reduced HIV-1 Tat phosphorylation by CDK2. Neither ICL670A or 311 decreased CDK9 protein level but significantly reduced association of CDK9 with cyclin T1 and reduced phosphorylation of Ser-2 residues of RNA polymerase II C-terminal domain. In conclusion, our findings add to the evidence that iron chelators can inhibit HIV-1 transcription by deregulating CDK2 and CDK9. Further consideration should be given to the development of iron chelators for future anti-retroviral therapeutics

  18. Nucleolar protein trafficking in response to HIV-1 Tat: rewiring the nucleolus.

    Science.gov (United States)

    Jarboui, Mohamed Ali; Bidoia, Carlo; Woods, Elena; Roe, Barbara; Wynne, Kieran; Elia, Giuliano; Hall, William W; Gautier, Virginie W

    2012-01-01

    The trans-activator Tat protein is a viral regulatory protein essential for HIV-1 replication. Tat trafficks to the nucleoplasm and the nucleolus. The nucleolus, a highly dynamic and structured membrane-less sub-nuclear compartment, is the site of rRNA and ribosome biogenesis and is involved in numerous cellular functions including transcriptional regulation, cell cycle control and viral infection. Importantly, transient nucleolar trafficking of both Tat and HIV-1 viral transcripts are critical in HIV-1 replication, however, the role(s) of the nucleolus in HIV-1 replication remains unclear. To better understand how the interaction of Tat with the nucleolar machinery contributes to HIV-1 pathogenesis, we investigated the quantitative changes in the composition of the nucleolar proteome of Jurkat T-cells stably expressing HIV-1 Tat fused to a TAP tag. Using an organellar proteomic approach based on mass spectrometry, coupled with Stable Isotope Labelling in Cell culture (SILAC), we quantified 520 proteins, including 49 proteins showing significant changes in abundance in Jurkat T-cell nucleolus upon Tat expression. Numerous proteins exhibiting a fold change were well characterised Tat interactors and/or known to be critical for HIV-1 replication. This suggests that the spatial control and subcellular compartimentaliation of these cellular cofactors by Tat provide an additional layer of control for regulating cellular machinery involved in HIV-1 pathogenesis. Pathway analysis and network reconstruction revealed that Tat expression specifically resulted in the nucleolar enrichment of proteins collectively participating in ribosomal biogenesis, protein homeostasis, metabolic pathways including glycolytic, pentose phosphate, nucleotides and amino acids biosynthetic pathways, stress response, T-cell signaling pathways and genome integrity. We present here the first differential profiling of the nucleolar proteome of T-cells expressing HIV-1 Tat. We discuss how these

  19. LTRsift: a graphical user interface for semi-automatic classification and postprocessing of de novo detected LTR retrotransposons.

    Science.gov (United States)

    Steinbiss, Sascha; Kastens, Sascha; Kurtz, Stefan

    2012-11-07

    Long terminal repeat (LTR) retrotransposons are a class of eukaryotic mobile elements characterized by a distinctive sequence similarity-based structure. Hence they are well suited for computational identification. Current software allows for a comprehensive genome-wide de novo detection of such elements. The obvious next step is the classification of newly detected candidates resulting in (super-)families. Such a de novo classification approach based on sequence-based clustering of transposon features has been proposed before, resulting in a preliminary assignment of candidates to families as a basis for subsequent manual refinement. However, such a classification workflow is typically split across a heterogeneous set of glue scripts and generic software (for example, spreadsheets), making it tedious for a human expert to inspect, curate and export the putative families produced by the workflow. We have developed LTRsift, an interactive graphical software tool for semi-automatic postprocessing of de novo predicted LTR retrotransposon annotations. Its user-friendly interface offers customizable filtering and classification functionality, displaying the putative candidate groups, their members and their internal structure in a hierarchical fashion. To ease manual work, it also supports graphical user interface-driven reassignment, splitting and further annotation of candidates. Export of grouped candidate sets in standard formats is possible. In two case studies, we demonstrate how LTRsift can be employed in the context of a genome-wide LTR retrotransposon survey effort. LTRsift is a useful and convenient tool for semi-automated classification of newly detected LTR retrotransposons based on their internal features. Its efficient implementation allows for convenient and seamless filtering and classification in an integrated environment. Developed for life scientists, it is helpful in postprocessing and refining the output of software for predicting LTR

  20. Nuclear Export Signal Masking Regulates HIV-1 Rev Trafficking and Viral RNA Nuclear Export.

    Science.gov (United States)

    Behrens, Ryan T; Aligeti, Mounavya; Pocock, Ginger M; Higgins, Christina A; Sherer, Nathan M

    2017-02-01

    HIV-1's Rev protein forms a homo-oligomeric adaptor complex linking viral RNAs to the cellular CRM1/Ran-GTP nuclear export machinery through the activity of Rev's prototypical leucine-rich nuclear export signal (NES). In this study, we used a functional fluorescently tagged Rev fusion protein as a platform to study the effects of modulating Rev NES identity, number, position, or strength on Rev subcellular trafficking, viral RNA nuclear export, and infectious virion production. We found that Rev activity was remarkably tolerant of diverse NES sequences, including supraphysiological NES (SNES) peptides that otherwise arrest CRM1 transport complexes at nuclear pores. Rev's ability to tolerate a SNES was both position and multimerization dependent, an observation consistent with a model wherein Rev self-association acts to transiently mask the NES peptide(s), thereby biasing Rev's trafficking into the nucleus. Combined imaging and functional assays also indicated that NES masking underpins Rev's well-known tendency to accumulate at the nucleolus, as well as Rev's capacity to activate optimal levels of late viral gene expression. We propose that Rev multimerization and NES masking regulates Rev's trafficking to and retention within the nucleus even prior to RNA binding. HIV-1 infects more than 34 million people worldwide causing >1 million deaths per year. Infectious virion production is activated by the essential viral Rev protein that mediates nuclear export of intron-bearing late-stage viral mRNAs. Rev's shuttling into and out of the nucleus is regulated by the antagonistic activities of both a peptide-encoded N-terminal nuclear localization signal and C-terminal nuclear export signal (NES). How Rev and related viral proteins balance strong import and export activities in order to achieve optimal levels of viral gene expression is incompletely understood. We provide evidence that multimerization provides a mechanism by which Rev transiently masks its NES peptide

  1. Akv murine leukemia virus enhances bone tumorigenesis in hMT-c-fos-LTR transgenic mice

    DEFF Research Database (Denmark)

    Schmidt, Jörg; Krump-Konvalinkova, Vera; Luz, Arne

    1995-01-01

    hMt-c-fos-LTR transgenic mice (U. Rüther, D. Komitowski, F. R. Schubert, and E. F. Wagner. Oncogene 4, 861–865, 1989) developed bone sarcomas in 20% (3/15) of females at 448 ± 25 days and in 8% (1/12) of males at 523 days. After infection of newborns with Akv, an infectious retrovirus derived from...

  2. MicroRNA profile changes in human immunodeficiency virus type 1 (HIV-1 seropositive individuals

    Directory of Open Access Journals (Sweden)

    Smith Stephen M

    2008-12-01

    Full Text Available Abstract MicroRNAs (miRNAs play diverse roles in regulating cellular and developmental functions. We have profiled the miRNA expression in peripheral blood mononuclear cells from 36 HIV-1 seropositive individuals and 12 normal controls. The HIV-1-positive individuals were categorized operationally into four classes based on their CD4+ T-cell counts and their viral loads. We report that specific miRNA signatures can be observed for each of the four classes.

  3. Unexpected Modulation of Recall B and T Cell Responses after Immunization with Rotavirus-like Particles in the Presence of LT-R192G

    Directory of Open Access Journals (Sweden)

    Christelle Basset

    2010-08-01

    Full Text Available LT-R192G, a mutant of the thermolabile enterotoxin of E. coli, is a potent adjuvant of immunization. Immune responses are generally analyzed at the end of protocols including at least 2 administrations, but rarely after a prime. To investigate this point, we compared B and T cell responses in mice after one and two intrarectal immunizations with 2/6 rotavirus-like particles (2/6-VLP and LT-R192G. After a boost, we found, an unexpected lower B cell expansion measured by flow cytometry, despite a secondary antibody response. We then analyzed CD4+CD25+Foxp3+ regulatory T cells (Tregs and CD4+CD25+Foxp3− helper T cells after in vitro (restimulation of mesenteric lymph node cells with the antigen (2/6-VLP, the adjuvant (LT-R192G or both. 2/6-VLP did not activate CD4+CD25+Foxp3− nor Foxp3+ T cells from non-immunized and 2/6-VLP immunized mice, whereas they did activate both subsets from mice immunized with 2/6-VLP in the presence of adjuvant. LT-R192G dramatically decreased CD4+CD25+Foxp3+ T cells from non-immunized and 2/6-VLP immunized mice but not from mice immunized with 2/6-VLP and adjuvant. Moreover, in this case, LT-R192G increased Foxp3 expression on CD4+CD25+Foxp3+ cells, suggesting specific Treg activation during the recall. Finally, when both 2/6-VLP and LT-R192G were used for restimulation, LT-R192G clearly suppressed both 2/6-VLP-specific CD4+CD25+Foxp3− and Foxp3+ T cells. All together, these results suggest that LT-R192G exerts different effects on CD4+CD25+Foxp3+ T cells, depending on a first or a second contact. The unexpected immunomodulation observed during the recall should be considered in designing vaccination protocols.

  4. Regulated production and anti-HIV type 1 activities of cytidine deaminases APOBEC3B, 3F, and 3G.

    Science.gov (United States)

    Rose, Kristine M; Marin, Mariana; Kozak, Susan L; Kabat, David

    2005-07-01

    APOBEC3G and 3F (A3G and A3F) cytidine deaminases incorporate into retroviral cores where they lethally hypermutate nascent DNA reverse transcripts. As substantiated here, the viral infectivity factor (Vif) encoded by human immunodeficiency virus type-1 (HIV-1) binds A3G and A3F and induces their degradation, thereby precluding their incorporation into viral progeny. Previous evidence suggested that A3G is expressed in H9 and other nonpermissive cells that contain this antiviral defense but not in several permissive cells, and that overexpression of A3G or A3F makes permissive cells nonpermissive. Using a broader panel of cell lines, we confirmed a correlation between A3G and cellular abilities to inactivate HIV-1(Deltavif). However, there was a quantitative discrepancy because several cells with weak antiviral activities had similar amounts of wild-type A3G mRNA and protein compared to H9 cells. Antiviral activity of H9 cells was also attenuated in some conditions. These quantitative discrepancies could not be explained by the presence of A3F or other A3G paralogs in some of the cell lines. Thus, A3A, A3B, and A3C had weak but significant anti-HIV-1 activities and did not dominantly interfere with A3G or A3F antiviral functions. Control of A3G synthesis by the protein kinase C/mitogen-activated protein kinase kinase/extracellular signal-regulated kinase pathway was also similar in permissive and nonpermissive cells. A3G in highly permissive cells is degraded by Vif, suggesting that it is not in a sequestered site, and is specifically incorporated in low amounts into HIV-1(Deltavif). Although A3G and/or A3F inactivate HIV-1(Deltavif) and are neutralized by Vif, the antiviral properties of cell lines are also influenced by other cellular and viral factors.

  5. Ancient Origin of the U2 Small Nuclear RNA Gene-Targeting Non-LTR Retrotransposons Utopia.

    Science.gov (United States)

    Kojima, Kenji K; Jurka, Jerzy

    2015-01-01

    Most non-long terminal repeat (non-LTR) retrotransposons encoding a restriction-like endonuclease show target-specific integration into repetitive sequences such as ribosomal RNA genes and microsatellites. However, only a few target-specific lineages of non-LTR retrotransposons are distributed widely and no lineage is found across the eukaryotic kingdoms. Here we report the most widely distributed lineage of target sequence-specific non-LTR retrotransposons, designated Utopia. Utopia is found in three supergroups of eukaryotes: Amoebozoa, SAR, and Opisthokonta. Utopia is inserted into a specific site of U2 small nuclear RNA genes with different strength of specificity for each family. Utopia families from oomycetes and wasps show strong target specificity while only a small number of Utopia copies from reptiles are flanked with U2 snRNA genes. Oomycete Utopia families contain an "archaeal" RNase H domain upstream of reverse transcriptase (RT), which likely originated from a plant RNase H gene. Analysis of Utopia from oomycetes indicates that multiple lineages of Utopia have been maintained inside of U2 genes with few copy numbers. Phylogenetic analysis of RT suggests the monophyly of Utopia, and it likely dates back to the early evolution of eukaryotes.

  6. Potent nonnucleoside reverse transcriptase inhibitors target HIV-1 Gag-Pol.

    Directory of Open Access Journals (Sweden)

    Anna Figueiredo

    2006-11-01

    Full Text Available Nonnucleoside reverse transcriptase inhibitors (NNRTIs target HIV-1 reverse transcriptase (RT by binding to a pocket in RT that is close to, but distinct, from the DNA polymerase active site and prevent the synthesis of viral cDNA. NNRTIs, in particular, those that are potent inhibitors of RT polymerase activity, can also act as chemical enhancers of the enzyme's inter-subunit interactions. However, the consequences of this chemical enhancement effect on HIV-1 replication are not understood. Here, we show that the potent NNRTIs efavirenz, TMC120, and TMC125, but not nevirapine or delavirdine, inhibit the late stages of HIV-1 replication. These potent NNRTIs enhanced the intracellular processing of Gag and Gag-Pol polyproteins, and this was associated with a decrease in viral particle production from HIV-1-transfected cells. The increased polyprotein processing is consistent with premature activation of the HIV-1 protease by NNRTI-enhanced Gag-Pol multimerization through the embedded RT sequence. These findings support the view that Gag-Pol multimerization is an important step in viral assembly and demonstrate that regulation of Gag-Pol/Gag-Pol interactions is a novel target for small molecule inhibitors of HIV-1 production. Furthermore, these drugs can serve as useful probes to further understand processes involved in HIV-1 particle assembly and maturation.

  7. Influenza vaccination of HIV-1-positive and HIV-1-negative former intravenous drug users.

    Science.gov (United States)

    Amendola, A; Boschini, A; Colzani, D; Anselmi, G; Oltolina, A; Zucconi, R; Begnini, M; Besana, S; Tanzi, E; Zanetti, A R

    2001-12-01

    The immunogenicity of an anti-influenza vaccine was assessed in 409 former intravenous drug user volunteers and its effect on the levels of HIV-1 RNA, proviral DNA and on CD4+ lymphocyte counts in a subset HIV-1-positive subjects was measured. HIV-1-positive individuals (n = 72) were divided into three groups on the basis of their CD4+ lymphocyte counts, while the 337 HIV-1-negative participants were allocated into group four. Haemagglutination inhibiting (HI) responses varied from 45.8 to 70% in the HIV-1-positive subjects and were significantly higher in group four (80.7% responses to the H1N1 strain, 81.6% to the H3N2 strain, and 83% to the B strain). The percentage of subjects with HI protective antibody titres (> or = 1:40) increased significantly after vaccination, especially in HIV-1 uninfected subjects. Immunization caused no significant changes in CD4+ counts and in neither plasma HIV-1 RNA nor proviral DNA levels. Therefore, vaccination against influenza may benefit persons infected by HIV-1. Copyright 2001 Wiley-Liss, Inc.

  8. Highly conserved serine residue 40 in HIV-1 p6 regulates capsid processing and virus core assembly

    Directory of Open Access Journals (Sweden)

    Solbak Sara MØ

    2011-02-01

    Full Text Available Abstract Background The HIV-1 p6 Gag protein regulates the final abscission step of nascent virions from the cell membrane by the action of two late assembly (L- domains. Although p6 is located within one of the most polymorphic regions of the HIV-1 gag gene, the 52 amino acid peptide binds at least to two cellular budding factors (Tsg101 and ALIX, is a substrate for phosphorylation, ubiquitination, and sumoylation, and mediates the incorporation of the HIV-1 accessory protein Vpr into viral particles. As expected, known functional domains mostly overlap with several conserved residues in p6. In this study, we investigated the importance of the highly conserved serine residue at position 40, which until now has not been assigned to any known function of p6. Results Consistently with previous data, we found that mutation of Ser-40 has no effect on ALIX mediated rescue of HIV-1 L-domain mutants. However, the only feasible S40F mutation that preserves the overlapping pol open reading frame (ORF reduces virus replication in T-cell lines and in human lymphocyte tissue cultivated ex vivo. Most intriguingly, L-domain mediated virus release is not dependent on the integrity of Ser-40. However, the S40F mutation significantly reduces the specific infectivity of released virions. Further, it was observed that mutation of Ser-40 selectively interferes with the cleavage between capsid (CA and the spacer peptide SP1 in Gag, without affecting cleavage of other Gag products. This deficiency in processing of CA, in consequence, led to an irregular morphology of the virus core and the formation of an electron dense extra core structure. Moreover, the defects induced by the S40F mutation in p6 can be rescued by the A1V mutation in SP1 that generally enhances processing of the CA-SP1 cleavage site. Conclusions Overall, these data support a so far unrecognized function of p6 mediated by Ser-40 that occurs independently of the L-domain function, but selectively

  9. Human-Phosphate-Binding-Protein inhibits HIV-1 gene transcription and replication

    Directory of Open Access Journals (Sweden)

    Candolfi Ermanno

    2011-07-01

    Full Text Available Abstract The Human Phosphate-Binding protein (HPBP is a serendipitously discovered lipoprotein that binds phosphate with high affinity. HPBP belongs to the DING protein family, involved in various biological processes like cell cycle regulation. We report that HPBP inhibits HIV-1 gene transcription and replication in T cell line, primary peripherical blood lymphocytes and primary macrophages. We show that HPBP is efficient in naïve and HIV-1 AZT-resistant strains. Our results revealed HPBP as a new and potent anti HIV molecule that inhibits transcription of the virus, which has not yet been targeted by HAART and therefore opens new strategies in the treatment of HIV infection.

  10. HMBA Enhances Prostratin-Induced Activation of Latent HIV-1 via Suppressing the Expression of Negative Feedback Regulator A20/TNFAIP3 in NF-κB Signaling

    Directory of Open Access Journals (Sweden)

    Duchu Chen

    2016-01-01

    Full Text Available In the past decade, much emphasis has been put on the transcriptional activation of HIV-1, which is proposed as a promised strategy for eradicating latent HIV-1 provirus. Two drugs, prostratin and hexamethylene bisacetamide (HMBA, have shown potent effects as inducers for releasing HIV-1 latency when used alone or in combination, although their cellular target(s are currently not well understood, especially under drug combination. Here, we have shown that HMBA and prostratin synergistically release HIV-1 latency via different mechanisms. While prostratin strongly stimulates HMBA-induced HIV-1 transcription via improved P-TEFb activation, HMBA is capable of boosting NF-κB-dependent transcription initiation by suppressing prostratin-induced expression of the deubiquitinase A20, a negative feedback regulator in the NF-κB signaling pathway. In addition, HMBA was able to increase prostratin-induced phosphorylation and degradation of NF-κB inhibitor IκBα, thereby enhancing and prolonging prostratin-induced nuclear translocation of NF-κB, a prerequisite for stimulation of transcription initiation. Thus, by blocking the negative feedback circuit, HMBA functions as a signaling enhancer of the NF-κB signaling pathway.

  11. Semen Bacterial Concentrations and HIV-1 RNA Shedding Among HIV-1-Seropositive Kenyan Men.

    Science.gov (United States)

    Korhonen, Christine J; Srinivasan, Sujatha; Huang, Dandi; Ko, Daisy L; Sanders, Eduard J; Peshu, Norbert M; Krieger, John N; Muller, Charles H; Coombs, Robert W; Fredricks, David N; Graham, Susan M

    2017-03-01

    HIV-1 is transmitted through semen from men to their sexual partners. Genital infections can increase HIV-1 RNA shedding in semen, but shedding also occurs in the absence of typical pathogens. We hypothesized that higher bacterial concentrations in semen would be associated with higher HIV-1 RNA levels. We analyzed semen samples from 42 HIV-1-seropositive Kenyan men using quantitative polymerase chain reaction (PCR) to assess bacterial concentrations and real-time PCR to measure HIV-1 RNA levels. Generalized estimation equations were used to evaluate associations between these 2 measures. Broad-range 16S rRNA gene PCR with pyrosequencing was performed on a subset of 13 samples to assess bacterial community composition. Bacteria were detected in 96.6% of 88 samples by quantitative PCR. Semen bacterial concentration and HIV-1 RNA levels were correlated 0.30 (P = 0.01). The association between bacterial concentration and HIV-1 RNA detection was not significant after adjustment for antiretroviral therapy (ART) (adjusted odds ratio: 1.27, 95% CI: 0.84 to 1.91). Factors associated with semen bacterial concentration included insertive anal sex (adjusted beta 0.92, 95% CI: 0.12 to 1.73) and ART use (adjusted beta: -0.77, 95% CI: -1.50 to 0.04). Among 13 samples with pyrosequencing data, Corynebacterium spp., Staphylococcus spp., and Streptococcus spp. were most frequently detected. Most of these HIV-1-infected men had bacteria in their semen. ART use was associated with undetectable semen HIV-1 RNA and lower semen bacterial concentrations, whereas insertive anal sex was associated with higher bacterial concentrations. Additional studies evaluating the relationship between semen bacteria, inflammation, mucosal immunity, and HIV-1 shedding are needed to understand implications for HIV-1 transmission.

  12. HIV-1 molecular epidemiology among newly diagnosed HIV-1 individuals in Hebei, a low HIV prevalence province in China.

    Science.gov (United States)

    Lu, Xinli; Kang, Xianjiang; Liu, Yongjian; Cui, Ze; Guo, Wei; Zhao, Cuiying; Li, Yan; Chen, Suliang; Li, Jingyun; Zhang, Yuqi; Zhao, Hongru

    2017-01-01

    New human immunodeficiency virus type 1 (HIV-1) diagnoses are increasing rapidly in Hebei. The aim of this study presents the most extensive HIV-1 molecular epidemiology investigation in Hebei province in China thus far. We have carried out the most extensive systematic cross-sectional study based on newly diagnosed HIV-1 positive individuals in 2013, and characterized the molecular epidemiology of HIV-1 based on full length gag-partial pol gene sequences in the whole of Hebei. Nine HIV-1 genotypes based on full length gag-partial pol gene sequence were identified among 610 newly diagnosed naïve individuals. The four main genotypes were circulating recombinant form (CRF)01_AE (53.4%), CRF07_BC (23.4%), subtype B (15.9%), and unique recombinant forms URFs (4.9%). Within 1 year, three new genotypes (subtype A1, CRF55_01B, CRF65_cpx), unknown before in Hebei, were first found among men who have sex with men (MSM). All nine genotypes were identified in the sexually contracted HIV-1 population. Among 30 URFs, six recombinant patterns were revealed, including CRF01_AE/BC (40.0%), CRF01_AE/B (23.3%), B/C (16.7%), CRF01_AE/C (13.3%), CRF01_AE/B/A2 (3.3%) and CRF01_AE/BC/A2 (3.3%), plus two potential CRFs. This study elucidated the complicated characteristics of HIV-1 molecular epidemiology in a low HIV-1 prevalence northern province of China and revealed the high level of HIV-1 genetic diversity. All nine HIV-1 genotypes circulating in Hebei have spread out of their initial risk groups into the general population through sexual contact, especially through MSM. This highlights the urgency of HIV prevention and control in China.

  13. HIV-1 molecular epidemiology among newly diagnosed HIV-1 individuals in Hebei, a low HIV prevalence province in China.

    Directory of Open Access Journals (Sweden)

    Xinli Lu

    Full Text Available New human immunodeficiency virus type 1 (HIV-1 diagnoses are increasing rapidly in Hebei. The aim of this study presents the most extensive HIV-1 molecular epidemiology investigation in Hebei province in China thus far. We have carried out the most extensive systematic cross-sectional study based on newly diagnosed HIV-1 positive individuals in 2013, and characterized the molecular epidemiology of HIV-1 based on full length gag-partial pol gene sequences in the whole of Hebei. Nine HIV-1 genotypes based on full length gag-partial pol gene sequence were identified among 610 newly diagnosed naïve individuals. The four main genotypes were circulating recombinant form (CRF01_AE (53.4%, CRF07_BC (23.4%, subtype B (15.9%, and unique recombinant forms URFs (4.9%. Within 1 year, three new genotypes (subtype A1, CRF55_01B, CRF65_cpx, unknown before in Hebei, were first found among men who have sex with men (MSM. All nine genotypes were identified in the sexually contracted HIV-1 population. Among 30 URFs, six recombinant patterns were revealed, including CRF01_AE/BC (40.0%, CRF01_AE/B (23.3%, B/C (16.7%, CRF01_AE/C (13.3%, CRF01_AE/B/A2 (3.3% and CRF01_AE/BC/A2 (3.3%, plus two potential CRFs. This study elucidated the complicated characteristics of HIV-1 molecular epidemiology in a low HIV-1 prevalence northern province of China and revealed the high level of HIV-1 genetic diversity. All nine HIV-1 genotypes circulating in Hebei have spread out of their initial risk groups into the general population through sexual contact, especially through MSM. This highlights the urgency of HIV prevention and control in China.

  14. LTRsift: a graphical user interface for semi-automatic classification and postprocessing of de novo detected LTR retrotransposons

    Directory of Open Access Journals (Sweden)

    Steinbiss Sascha

    2012-11-01

    Full Text Available Abstract Background Long terminal repeat (LTR retrotransposons are a class of eukaryotic mobile elements characterized by a distinctive sequence similarity-based structure. Hence they are well suited for computational identification. Current software allows for a comprehensive genome-wide de novo detection of such elements. The obvious next step is the classification of newly detected candidates resulting in (super-families. Such a de novo classification approach based on sequence-based clustering of transposon features has been proposed before, resulting in a preliminary assignment of candidates to families as a basis for subsequent manual refinement. However, such a classification workflow is typically split across a heterogeneous set of glue scripts and generic software (for example, spreadsheets, making it tedious for a human expert to inspect, curate and export the putative families produced by the workflow. Results We have developed LTRsift, an interactive graphical software tool for semi-automatic postprocessing of de novo predicted LTR retrotransposon annotations. Its user-friendly interface offers customizable filtering and classification functionality, displaying the putative candidate groups, their members and their internal structure in a hierarchical fashion. To ease manual work, it also supports graphical user interface-driven reassignment, splitting and further annotation of candidates. Export of grouped candidate sets in standard formats is possible. In two case studies, we demonstrate how LTRsift can be employed in the context of a genome-wide LTR retrotransposon survey effort. Conclusions LTRsift is a useful and convenient tool for semi-automated classification of newly detected LTR retrotransposons based on their internal features. Its efficient implementation allows for convenient and seamless filtering and classification in an integrated environment. Developed for life scientists, it is helpful in postprocessing and refining

  15. HIV-1 vaccines

    Science.gov (United States)

    Excler, Jean-Louis; Robb, Merlin L; Kim, Jerome H

    2014-01-01

    The development of a safe and effective preventive HIV-1 vaccine remains a public health priority. Despite scientific difficulties and disappointing results, HIV-1 vaccine clinical development has, for the first time, established proof-of-concept efficacy against HIV-1 acquisition and identified vaccine-associated immune correlates of risk. The correlate of risk analysis showed that IgG antibodies against the gp120 V2 loop correlated with decreased risk of HIV infection, while Env-specific IgA directly correlated with increased risk. The development of vaccine strategies such as improved envelope proteins formulated with potent adjuvants and DNA and vectors expressing mosaics, or conserved sequences, capable of eliciting greater breadth and depth of potentially relevant immune responses including neutralizing and non-neutralizing antibodies, CD4+ and CD8+ cell-mediated immune responses, mucosal immune responses, and immunological memory, is now proceeding quickly. Additional human efficacy trials combined with other prevention modalities along with sustained funding and international collaboration remain key to bring an HIV-1 vaccine to licensure. PMID:24637946

  16. Toll-like receptor 3 signalling up-regulates expression of the HIV co-receptor G-protein coupled receptor 15 on human CD4+ T cells.

    Directory of Open Access Journals (Sweden)

    Miriam Kiene

    Full Text Available BACKGROUND: Many HIV-2 and SIV isolates, as well as some HIV-1 strains, can use the orphan 7-transmembrane receptor GPR15 as co-receptor for efficient entry into host cells. GPR15 is expressed on central memory and effector memory CD4(+ T cells in healthy individuals and a subset of these cells is susceptible to HIV-1 and SIV infection. However, it has not been determined whether GPR15 expression is altered in the context of HIV-1 infection. RESULTS: Here, we show that GPR15 expression in CD4(+ T cells is markedly up-regulated in some HIV-1 infected individuals compared to the rest of the infected patients and to healthy controls. Infection of the PM1 T cell line with primary HIV-1 isolates was found to up-regulate GPR15 expression on the infected cells, indicating that viral components can induce GPR15 expression. Up-regulation of GPR15 expression on CD4(+ T cells was induced by activation of Toll-like receptor 3 signalling via TIR-domain-containing adapter-inducing interferon-β (TRIF and was more prominent on gut-homing compared to lymph node-homing CD4(+ T cells. CONCLUSION: These results suggest that infection-induced up-regulation of GPR15 expression could increase susceptibility of CD4(+ T cells to HIV infection and target cell availability in the gut in some infected individuals.

  17. Direct effects of HIV-1 Tat on excitability and survival of primary dorsal root ganglion neurons: possible contribution to HIV-1-associated pain.

    Directory of Open Access Journals (Sweden)

    Xianxun Chi

    Full Text Available The vast majority of people living with human immunodeficiency virus type 1 (HIV-1 have pain syndrome, which has a significant impact on their quality of life. The underlying causes of HIV-1-associated pain are not likely attributable to direct viral infection of the nervous system due to the lack of evidence of neuronal infection by HIV-1. However, HIV-1 proteins are possibly involved as they have been implicated in neuronal damage and death. The current study assesses the direct effects of HIV-1 Tat, one of potent neurotoxic viral proteins released from HIV-1-infected cells, on the excitability and survival of rat primary dorsal root ganglion (DRG neurons. We demonstrated that HIV-1 Tat triggered rapid and sustained enhancement of the excitability of small-diameter rat primary DRG neurons, which was accompanied by marked reductions in the rheobase and resting membrane potential (RMP, and an increase in the resistance at threshold (R(Th. Such Tat-induced DRG hyperexcitability may be a consequence of the inhibition of cyclin-dependent kinase 5 (Cdk5 activity. Tat rapidly inhibited Cdk5 kinase activity and mRNA production, and roscovitine, a well-known Cdk5 inhibitor, induced a very similar pattern of DRG hyperexcitability. Indeed, pre-application of Tat prevented roscovitine from having additional effects on the RMP and action potentials (APs of DRGs. However, Tat-mediated actions on the rheobase and R(Th were accelerated by roscovitine. These results suggest that Tat-mediated changes in DRG excitability are partly facilitated by Cdk5 inhibition. In addition, Cdk5 is most abundant in DRG neurons and participates in the regulation of pain signaling. We also demonstrated that HIV-1 Tat markedly induced apoptosis of primary DRG neurons after exposure for longer than 48 h. Together, this work indicates that HIV-1 proteins are capable of producing pain signaling through direct actions on excitability and survival of sensory neurons.

  18. Mammalian-specific genomic functions: Newly acquired traits generated by genomic imprinting and LTR retrotransposon-derived genes in mammals.

    Science.gov (United States)

    Kaneko-Ishino, Tomoko; Ishino, Fumitoshi

    2015-01-01

    Mammals, including human beings, have evolved a unique viviparous reproductive system and a highly developed central nervous system. How did these unique characteristics emerge in mammalian evolution, and what kinds of changes did occur in the mammalian genomes as evolution proceeded? A key conceptual term in approaching these issues is "mammalian-specific genomic functions", a concept covering both mammalian-specific epigenetics and genetics. Genomic imprinting and LTR retrotransposon-derived genes are reviewed as the representative, mammalian-specific genomic functions that are essential not only for the current mammalian developmental system, but also mammalian evolution itself. First, the essential roles of genomic imprinting in mammalian development, especially related to viviparous reproduction via placental function, as well as the emergence of genomic imprinting in mammalian evolution, are discussed. Second, we introduce the novel concept of "mammalian-specific traits generated by mammalian-specific genes from LTR retrotransposons", based on the finding that LTR retrotransposons served as a critical driving force in the mammalian evolution via generating mammalian-specific genes.

  19. A DEAD box protein facilitates HIV-1 replication as a cellular co-factor of Rev

    International Nuclear Information System (INIS)

    Fang Jianhua; Kubota, Satoshi; Yang Bin; Zhou Naiming; Zhang Hui; Godbout, Roseline; Pomerantz, Roger J.

    2004-01-01

    HIV-1 Rev escorts unspliced viral mRNAs out of the nucleus of infected cells, which allows formation of infectious HIV-1 virions. We have identified a putative DEAD box (Asp-Glu-Ala-Asp) RNA helicase, DDX1, as a cellular co-factor of Rev, through yeast and mammalian two-hybrid systems using the N-terminal motif of Rev as 'bait'. DDX1 is not a functional homolog of HIV-1 Rev, but down-regulation of DDX1 resulted in an alternative splicing pattern of Rev-responsive element (RRE)-containing mRNA, and attenuation of Gag p24 antigen production from HLfb rev(-) cells rescued by exogenous Rev. Co-transfection of a DDX1 expression vector with HIV-1 significantly increased viral production. DDX1 binding to Rev, as well as to the RRE, strongly suggest that DDX1 affects Rev function through the Rev-RRE axis. Moreover, down-regulation of DDX1 altered the steady state subcellular distribution of Rev, from nuclear/nucleolar to cytoplasmic dominance. These findings indicate that DDX1 is a critical cellular co-factor for Rev function, which maintains the proper subcellular distribution of this lentiviral regulatory protein. Therefore, alterations in DDX1-Rev interactions could induce HIV-1 persistence and targeting DDX1 may lead to rationally designed and novel anti-HIV-1 strategies and therapeutics

  20. Trans-dissemination of exosomes from HIV-1-infected cells fosters both HIV-1 trans-infection in resting CD4+ T lymphocytes and reactivation of the HIV-1 reservoir.

    Science.gov (United States)

    Chiozzini, Chiara; Arenaccio, Claudia; Olivetta, Eleonora; Anticoli, Simona; Manfredi, Francesco; Ferrantelli, Flavia; d'Ettorre, Gabriella; Schietroma, Ivan; Andreotti, Mauro; Federico, Maurizio

    2017-09-01

    Intact HIV-1 and exosomes can be internalized by dendritic cells (DCs) through a common pathway leading to their transmission to CD4 + T lymphocytes by means of mechanisms defined as trans-infection and trans-dissemination, respectively. We previously reported that exosomes from HIV-1-infected cells activate both uninfected quiescent CD4 + T lymphocytes, which become permissive to HIV-1, and latently infected cells, with release of HIV-1 particles. However, nothing is known about the effects of trans-dissemination of exosomes produced by HIV-1-infected cells on uninfected or latently HIV-1-infected CD4 + T lymphocytes. Here, we report that trans-dissemination of exosomes from HIV-1-infected cells induces cell activation in resting CD4 + T lymphocytes, which appears stronger with mature than immature DCs. Using purified preparations of both HIV-1 and exosomes, we observed that mDC-mediated trans-dissemination of exosomes from HIV-1-infected cells to resting CD4 + T lymphocytes induces efficient trans-infection and HIV-1 expression in target cells. Most relevant, when both mDCs and CD4 + T lymphocytes were isolated from combination anti-retroviral therapy (ART)-treated HIV-1-infected patients, trans-dissemination of exosomes from HIV-1-infected cells led to HIV-1 reactivation from the viral reservoir. In sum, our data suggest a role of exosome trans-dissemination in both HIV-1 spread in the infected host and reactivation of the HIV-1 reservoir.

  1. Evolutionary characterization of Ty3/gypsy-like LTR retrotransposons in the parasitic cestode Echinococcus granulosus.

    Science.gov (United States)

    Bae, Young-An

    2016-11-01

    Cyclophyllidean cestodes including Echinococcus granulosus have a smaller genome and show characteristics such as loss of the gut, a segmented body plan, and accelerated growth rate in hosts compared with other tissue-invading helminths. In an effort to address the molecular mechanism relevant to genome shrinkage, the evolutionary status of long-terminal-repeat (LTR) retrotransposons, which are known as the most potent genomic modulators, was investigated in the E. granulosus draft genome. A majority of the E. granulosus LTR retrotransposons were classified into a novel characteristic clade, named Saci-2, of the Ty3/gypsy family, while the remaining elements belonged to the CsRn1 clade of identical family. Their nucleotide sequences were heavily corrupted by frequent base substitutions and segmental losses. The ceased mobile activity of the major retrotransposons and the following intrinsic DNA loss in their inactive progenies might have contributed to decrease in genome size. Apart from the degenerate copies, a gag gene originating from a CsRn1-like element exhibited substantial evidences suggesting its domestication including a preserved coding profile and transcriptional activity, the presence of syntenic orthologues in cestodes, and selective pressure acting on the gene. To my knowledge, the endogenized gag gene is reported for the first time in invertebrates, though its biological function remains elusive.

  2. Role of MRP transporters in regulating antimicrobial drug inefficacy and oxidative stress-induced pathogenesis during HIV-1 and TB infections.

    Science.gov (United States)

    Roy, Upal; Barber, Paul; Tse-Dinh, Yuk-Ching; Batrakova, Elena V; Mondal, Debasis; Nair, Madhavan

    2015-01-01

    Multi-Drug Resistance Proteins (MRPs) are members of the ATP binding cassette (ABC) drug-efflux transporter superfamily. MRPs are known to regulate the efficacy of a broad range of anti-retroviral drugs (ARV) used in highly active antiretroviral therapy (HAART) and antibacterial agents used in Tuberculus Bacilli (TB) therapy. Due to their role in efflux of glutathione (GSH) conjugated drugs, MRPs can also regulate cellular oxidative stress, which may contribute to both HIV and/or TB pathogenesis. This review focuses on the characteristics, functional expression, and modulation of known members of the MRP family in HIV infected cells exposed to ARV drugs and discusses their known role in drug-inefficacy in HIV/TB-induced dysfunctions. Currently, nine members of the MRP family (MRP1-MRP9) have been identified, with MRP1 and MRP2 being the most extensively studied. Details of the other members of this family have not been known until recently, but differential expression has been documented in inflammatory tissues. Researchers have found that the distribution, function, and reactivity of members of MRP family vary in different types of lymphocytes and macrophages, and are differentially expressed at the basal and apical surfaces of both endothelial and epithelial cells. Therefore, the prime objective of this review is to delineate the role of MRP transporters in HAART and TB therapy and their potential in precipitating cellular dysfunctions manifested in these chronic infectious diseases. We also provide an overview of different available options and novel experimental strategies that are being utilized to overcome the drug resistance and disease pathogenesis mediated by these membrane transporters.

  3. Role of MRP Transporters in Regulating Antimicrobial Drug Inefficacy and Oxidative Stress-induced Pathogenesis during HIV-1 and TB Infections

    Directory of Open Access Journals (Sweden)

    Upal eRoy

    2015-09-01

    Full Text Available Multi-Drug Resistance Proteins (MRPs are members of the ATP binding cassette (ABC drug-efflux transporter superfamily. MRPs are known to regulate the efficacy of a broad range of anti-retroviral drugs (ARV used in highly active antiretroviral therapy (HAART and antibacterial agents used in Tuberculus Bacilli (TB therapy. Due to their role in efflux of glutathione (GSH conjugated drugs, MRPs can also regulate cellular oxidative stress, which may contribute to both HIV and/or TB pathogenesis. This review focuses on the characteristics, functional expression, and modulation of known members of the MRP family in HIV infected cells exposed to ARV drugs and discusses their known role in drug-inefficacy in HIV/TB-induced dysfunctions. Currently, nine members of the MRP family (MRP1-MRP9 have been identified, with MRP1 and MRP2 being the most extensively studied. Details of the other members of this family have not been known until recently, but differential expression has been documented in inflammatory tissues. Researchers have found that the distribution, function and reactivity of members of MRP family vary in different types of lymphocytes and macrophages, and are differentially expressed at the basal and apical surfaces of both endothelial and epithelial cells. Therefore, the prime objective of this review is to delineate the role of MRP transporters in HAART and TB therapy and their potential in precipitating cellular dysfunctions manifested in these chronic infectious diseases. We also provide an overview of different available options and novel experimental strategies that are being utilized to overcome the drug resistance and disease pathogenesis mediated by these membrane transporters.

  4. HIV-1 Infection of Primary CD4+ T Cells Regulates the Expression of Specific Human Endogenous Retrovirus HERV-K (HML-2) Elements.

    Science.gov (United States)

    Young, George R; Terry, Sandra N; Manganaro, Lara; Cuesta-Dominguez, Alvaro; Deikus, Gintaras; Bernal-Rubio, Dabeiba; Campisi, Laura; Fernandez-Sesma, Ana; Sebra, Robert; Simon, Viviana; Mulder, Lubbertus C F

    2018-01-01

    Endogenous retroviruses (ERVs) occupy extensive regions of the human genome. Although many of these retroviral elements have lost their ability to replicate, those whose insertion took place more recently, such as the HML-2 group of HERV-K elements, still retain intact open reading frames and the capacity to produce certain viral RNA and/or proteins. Transcription of these ERVs is, however, tightly regulated by dedicated epigenetic control mechanisms. Nonetheless, it has been reported that some pathological states, such as viral infections and certain cancers, coincide with ERV expression, suggesting that transcriptional reawakening is possible. HML-2 elements are reportedly induced during HIV-1 infection, but the conserved nature of these elements has, until recently, rendered their expression profiling problematic. Here, we provide comprehensive HERV-K HML-2 expression profiles specific for productively HIV-1-infected primary human CD4 + T cells. We combined enrichment of HIV-1 infected cells using a reporter virus expressing a surface reporter for gentle and efficient purification with long-read single-molecule real-time sequencing. We show that three HML-2 proviruses-6q25.1, 8q24.3, and 19q13.42-are upregulated on average between 3- and 5-fold in HIV-1-infected CD4 + T cells. One provirus, HML-2 12q24.33, in contrast, was repressed in the presence of active HIV replication. In conclusion, this report identifies the HERV-K HML-2 loci whose expression profiles differ upon HIV-1 infection in primary human CD4 + T cells. These data will help pave the way for further studies on the influence of endogenous retroviruses on HIV-1 replication. IMPORTANCE Endogenous retroviruses inhabit big portions of our genome. Moreover, although they are mainly inert, some of the evolutionarily younger members maintain the ability to express both RNA and proteins. We have developed an approach using long-read single-molecule real-time (SMRT) sequencing that produces long reads that

  5. Developing strategies for HIV-1 eradication

    Science.gov (United States)

    Durand, Christine M.; Blankson, Joel N.; Siliciano, Robert F.

    2014-01-01

    Highly active antiretroviral therapy (HAART) suppresses HIV-1 replication, transforming the outlook for infected patients. However, reservoirs of replication-competent forms of the virus persist during HAART, and when treatment is stopped, high rates of HIV-1 replication return. Recent insights into HIV-1 latency, as well as a report that HIV-1 infection was eradicated in one individual, have renewed interest in finding a cure for HIV-1 infection. Strategies for HIV-1 eradication include gene therapy and hematopoietic stem cell transplantation, stimulating host immunity to control HIV-1 replication, and targeting latent HIV-1 in resting memory CD4+ T cells. Future efforts should aim to provide better understanding of how to reconstitute the CD4+ T cell compartment with genetically engineered cells, exert immune control over HIV-1 replication, and identify and eliminate all viral reservoirs. PMID:22867874

  6. Human immunodeficiency virus long terminal repeat responds to T-cell activation signals

    International Nuclear Information System (INIS)

    Tong-Starksen, S.E.; Luciw, P.A.; Peterlin, B.M.

    1987-01-01

    Human immunodeficiency virus (HIV), the causative agent of AIDS, infects and kills lymphoid cells bearing the CD4 antigen. In an infected cell, a number of cellular as well as HIV-encoded gene products determine the levels of viral gene expression and HIV replication. Efficient HIV replication occurs in activated T cells. Utilizing transient expression assays, the authors show that gene expression directed by the HIV long terminal repeat (LTR) increases in response to T-cell activation signals. The effects of T-cell activation and of the HIV-encoded trans-activator (TAT) are multiplicative. Analysis of mutations and deletions in the HIV LTR reveals that the region responding to T-cell activation signals is located at positions -105 to -80. These sequences are composed of two direct repeats, which are homologous to the core transcriptional enhancer elements in the simian virus 40 genome. The studies reveal that these elements function as the HIV enhancer. By acting directly on the HIV LTR, T-cell activation may play an important role in HIV gene expression and in the activation of latent HIV

  7. Semen Bacterial Concentrations and HIV-1 RNA Shedding Among HIV-1–Seropositive Kenyan Men

    Science.gov (United States)

    Srinivasan, Sujatha; Huang, Dandi; Ko, Daisy L.; Sanders, Eduard J.; Peshu, Norbert M.; Krieger, John N.; Muller, Charles H.; Coombs, Robert W.; Fredricks, David N.; Graham, Susan M.

    2017-01-01

    Introduction: HIV-1 is transmitted through semen from men to their sexual partners. Genital infections can increase HIV-1 RNA shedding in semen, but shedding also occurs in the absence of typical pathogens. We hypothesized that higher bacterial concentrations in semen would be associated with higher HIV-1 RNA levels. Methods: We analyzed semen samples from 42 HIV-1–seropositive Kenyan men using quantitative polymerase chain reaction (PCR) to assess bacterial concentrations and real-time PCR to measure HIV-1 RNA levels. Generalized estimation equations were used to evaluate associations between these 2 measures. Broad-range 16S rRNA gene PCR with pyrosequencing was performed on a subset of 13 samples to assess bacterial community composition. Results: Bacteria were detected in 96.6% of 88 samples by quantitative PCR. Semen bacterial concentration and HIV-1 RNA levels were correlated 0.30 (P = 0.01). The association between bacterial concentration and HIV-1 RNA detection was not significant after adjustment for antiretroviral therapy (ART) (adjusted odds ratio: 1.27, 95% CI: 0.84 to 1.91). Factors associated with semen bacterial concentration included insertive anal sex (adjusted beta 0.92, 95% CI: 0.12 to 1.73) and ART use (adjusted beta: −0.77, 95% CI: −1.50 to 0.04). Among 13 samples with pyrosequencing data, Corynebacterium spp., Staphylococcus spp., and Streptococcus spp. were most frequently detected. Conclusion: Most of these HIV-1–infected men had bacteria in their semen. ART use was associated with undetectable semen HIV-1 RNA and lower semen bacterial concentrations, whereas insertive anal sex was associated with higher bacterial concentrations. Additional studies evaluating the relationship between semen bacteria, inflammation, mucosal immunity, and HIV-1 shedding are needed to understand implications for HIV-1 transmission. PMID:27861240

  8. Editing of HIV-1 RNA by the double-stranded RNA deaminase ADAR1 stimulates viral infection

    Science.gov (United States)

    Doria, Margherita; Neri, Francesca; Gallo, Angela; Farace, Maria Giulia; Michienzi, Alessandro

    2009-01-01

    Adenosine deaminases that act on dsRNA (ADARs) are enzymes that target double-stranded regions of RNA converting adenosines into inosines (A-to-I editing) thus contributing to genome complexity and fine regulation of gene expression. It has been described that a member of the ADAR family, ADAR1, can target viruses and affect their replication process. Here we report evidence showing that ADAR1 stimulates human immuno deficiency virus type 1 (HIV-1) replication by using both editing-dependent and editing-independent mechanisms. We show that over-expression of ADAR1 in HIV-1 producer cells increases viral protein accumulation in an editing-independent manner. Moreover, HIV-1 virions generated in the presence of over-expressed ADAR1 but not an editing-inactive ADAR1 mutant are released more efficiently and display enhanced infectivity, as demonstrated by challenge assays performed with T cell lines and primary CD4+ T lymphocytes. Finally, we report that ADAR1 associates with HIV-1 RNAs and edits adenosines in the 5′ untranslated region (UTR) and the Rev and Tat coding sequence. Overall these results suggest that HIV-1 has evolved mechanisms to take advantage of specific RNA editing activity of the host cell and disclose a stimulatory function of ADAR1 in the spread of HIV-1. PMID:19651874

  9. Increased Risk of HIV-1 Transmission in Pregnancy: A Prospective Study among African HIV-1 Serodiscordant Couples

    Science.gov (United States)

    MUGO, Nelly R.; HEFFRON, Renee; DONNELL, Deborah; WALD, Anna; WERE, Edwin O.; REES, Helen; CELUM, Connie; KIARIE, James N.; COHEN, Craig R.; KAYINTEKORE, Kayitesi; BAETEN, Jared M.

    2011-01-01

    Background Physiologic and behavioral changes during pregnancy may alter HIV-1 susceptibility and infectiousness. Prospective studies exploring pregnancy and HIV-1 acquisition risk in women have found inconsistent results. No study has explored the effect of pregnancy on HIV-1 transmission risk from HIV-1 infected women to male partners. Methods In a prospective study of African HIV-1 serodiscordant couples, we evaluated the relationship between pregnancy and the risk of 1) HIV-1 acquisition among women and 2) HIV-1 transmission from women to men. Results 3321 HIV-1 serodiscordant couples were enrolled, 1085 (32.7%) with HIV-1 susceptible female partners and 2236 (67.3%) with susceptible male partners. HIV-1 incidence in women was 7.35 versus 3.01 per 100 person-years during pregnant and non-pregnant periods (hazard ratio [HR] 2.34, 95% confidence interval [CI] 1.33–4.09). This effect was attenuated and not statistically significant after adjusting for sexual behavior and other confounding factors (adjusted HR 1.71, 95% CI 0.93–3.12). HIV-1 incidence in male partners of infected women was 3.46 versus 1.58 per 100 person-years when their partners were pregnant versus not pregnant (HR 2.31, 95% CI 1.22–4.39). This effect was not attenuated in adjusted analysis (adjusted HR 2.47, 95% CI 1.26–4.85). Conclusions HIV-1 risk increased two-fold during pregnancy. Elevated risk of HIV-1 acquisition in pregnant women appeared in part to be explained by behavioral and other factors. This is the first study to show pregnancy increased the risk of female-to-male HIV-1 transmission, which may reflect biological changes of pregnancy that could increase HIV-1 infectiousness. PMID:21785321

  10. In vitro nuclear interactome of the HIV-1 Tat protein.

    LENUS (Irish Health Repository)

    Gautier, Virginie W

    2009-01-01

    BACKGROUND: One facet of the complexity underlying the biology of HIV-1 resides not only in its limited number of viral proteins, but in the extensive repertoire of cellular proteins they interact with and their higher-order assembly. HIV-1 encodes the regulatory protein Tat (86-101aa), which is essential for HIV-1 replication and primarily orchestrates HIV-1 provirus transcriptional regulation. Previous studies have demonstrated that Tat function is highly dependent on specific interactions with a range of cellular proteins. However they can only partially account for the intricate molecular mechanisms underlying the dynamics of proviral gene expression. To obtain a comprehensive nuclear interaction map of Tat in T-cells, we have designed a proteomic strategy based on affinity chromatography coupled with mass spectrometry. RESULTS: Our approach resulted in the identification of a total of 183 candidates as Tat nuclear partners, 90% of which have not been previously characterised. Subsequently we applied in silico analysis, to validate and characterise our dataset which revealed that the Tat nuclear interactome exhibits unique signature(s). First, motif composition analysis highlighted that our dataset is enriched for domains mediating protein, RNA and DNA interactions, and helicase and ATPase activities. Secondly, functional classification and network reconstruction clearly depicted Tat as a polyvalent protein adaptor and positioned Tat at the nexus of a densely interconnected interaction network involved in a range of biological processes which included gene expression regulation, RNA biogenesis, chromatin structure, chromosome organisation, DNA replication and nuclear architecture. CONCLUSION: We have completed the in vitro Tat nuclear interactome and have highlighted its modular network properties and particularly those involved in the coordination of gene expression by Tat. Ultimately, the highly specialised set of molecular interactions identified will

  11. Dendritic cells exposed to MVA-based HIV-1 vaccine induce highly functional HIV-1-specific CD8(+ T cell responses in HIV-1-infected individuals.

    Directory of Open Access Journals (Sweden)

    Núria Climent

    Full Text Available Currently, MVA virus vectors carrying HIV-1 genes are being developed as HIV-1/AIDS prophylactic/therapeutic vaccines. Nevertheless, little is known about the impact of these vectors on human dendritic cells (DC and their capacity to present HIV-1 antigens to human HIV-specific T cells. This study aimed to characterize the interaction of MVA and MVA expressing the HIV-1 genes Env-Gag-Pol-Nef of clade B (referred to as MVA-B in human monocyte-derived dendritic cells (MDDC and the subsequent processes of HIV-1 antigen presentation and activation of memory HIV-1-specific T lymphocytes. For these purposes, we performed ex vivo assays with MDDC and autologous lymphocytes from asymptomatic HIV-infected patients. Infection of MDDC with MVA-B or MVA, at the optimal dose of 0.3 PFU/MDDC, induced by itself a moderate degree of maturation of MDDC, involving secretion of cytokines and chemokines (IL1-ra, IL-7, TNF-α, IL-6, IL-12, IL-15, IL-8, MCP-1, MIP-1α, MIP-1β, RANTES, IP-10, MIG, and IFN-α. MDDC infected with MVA or MVA-B and following a period of 48 h or 72 h of maturation were able to migrate toward CCL19 or CCL21 chemokine gradients. MVA-B infection induced apoptosis of the infected cells and the resulting apoptotic bodies were engulfed by the uninfected MDDC, which cross-presented HIV-1 antigens to autologous CD8(+ T lymphocytes. MVA-B-infected MDDC co-cultured with autologous T lymphocytes induced a highly functional HIV-specific CD8(+ T cell response including proliferation, secretion of IFN-γ, IL-2, TNF-α, MIP-1β, MIP-1α, RANTES and IL-6, and strong cytotoxic activity against autologous HIV-1-infected CD4(+ T lymphocytes. These results evidence the adjuvant role of the vector itself (MVA and support the clinical development of prophylactic and therapeutic anti-HIV vaccines based on MVA-B.

  12. HIV-1 resistance conferred by siRNA cosuppression of CXCR4 and CCR5 coreceptors by a bispecific lentiviral vector

    Directory of Open Access Journals (Sweden)

    Akkina Ramesh

    2005-01-01

    Full Text Available Abstract Background RNA interference (RNAi mediated by small interfering RNAs (siRNAs has proved to be a highly effective gene silencing mechanism with great potential for HIV/AIDS gene therapy. Previous work with siRNAs against cellular coreceptors CXCR4 and CCR5 had shown that down regulation of these surface molecules could prevent HIV-1 entry and confer viral resistance. Since monospecific siRNAs targeting individual coreceptors are inadequate in protecting against both T cell tropic (X4 and monocyte tropic (R5 viral strains simultaneously, bispecific constructs with dual specificity are required. For effective long range therapy, the bispecific constructs need to be stably transduced into HIV-1 target cells via integrating viral vectors. Results To achieve this goal, lentiviral vectors incorporating both CXCR4 and CCR5 siRNAs of short hairpin design were constructed. The CXCR4 siRNA was driven by a U6 promoter whereas the CCR5 siRNA was driven by an H1 promoter. A CMV promoter driven EGFP reporter gene is also incorporated in the bispecific construct. High efficiency transduction into coreceptor expressing Magi and Ghost cell lines with a concomitant down regulation of respective coreceptors was achieved with lentiviral vectors. When the siRNA expressing transduced cells were challenged with X4 and R5 tropic HIV-1, they demonstrated marked viral resistance. HIV-1 resistance was also observed in bispecific lentiviral vector transduced primary PBMCs. Conclusions Both CXCR4 and CCR5 coreceptors could be simultaneously targeted for down regulation by a single combinatorial lentiviral vector incorporating respective anti-coreceptor siRNAs. Stable down regulation of both the coreceptors protects cells against infection by both X4 and R5 tropic HIV-1. Stable down regulation of cellular molecules that aid in HIV-1 infection will be an effective strategy for long range HIV gene therapy.

  13. Role of Bruton’s Tyrosine Kinase inhibitors in HIV-1 infected cells

    Science.gov (United States)

    Guendel, Irene; Iordanskiy, Sergey; Sampey, Gavin C; Van Duyne, Rachel; Calvert, Valerie; Petricoin, Emanuel; Saifuddin, Mohammed; Kehn-Hall, Kylene; Kashanchi, Fatah

    2015-01-01

    Many cellular cofactors have been documented to be critical for various stages of viral replication. Using high throughput proteomic assays, we have previously identified Bruton’s tyrosine kinase (BTK) as a host protein that was uniquely up-regulated in the plasma membrane of HIV-1 infected T-cells. Here, we have further characterized the BTK expression in HIV-1 infection and show that this cellular factor is specifically expressed in infected myeloid cells. Significant up-regulation of the phosphorylated form of BTK was observed in infected cells. Using size exclusion chromatography, we found BTK to be virtually absent in the uninfected U937 cells, however new BTK protein complexes were identified and distributed in both high molecular weight (~600 kDa) and a small molecular weight complex (~60–120 kDa) in the infected U1 cells. BTK levels were highest in cells either chronically expressing virus or induced/infected myeloid cells and that BTK translocated to the membrane following induction of the infected cells. BTK knockdown in HIV-1 infected cells using siRNA resulted in selective death of infected, but not uninfected, cells. Using BTK specific antibody and small molecule inhibitors including LFM-A13 and a FDA approved compound, Ibrutinib (PCI – 32765), we have found that HIV-1 infected cells are sensitive to apoptotic cell death and result in a decrease in virus production. Overall, our data suggests that HIV-1 infected cells are sensitive to treatments targeting BTK expressed in infected cells. PMID:25672887

  14. Low doses of neutrons induce changes in gene expression

    International Nuclear Information System (INIS)

    Woloschak, G.E.; Chang-Liu, C.M.; Panozzo, J.; Libertin, C.R.

    1993-01-01

    Studies were designed to identify genes induced following low-dose neutron but not following γ-ray exposure in fibroblasts. Our past work had shown differences in the expression of β-protein kinase C and c-fos genes, both being induced following γ-ray but not neutron exposure. We have identified two genes that are induced following neutron, but not γ-ray, exposure: Rp-8 (a gene induced by apoptosis) and the long terminal repeat (LTR) of the human immunodeficiency (HIV). Rp-8 mRNA induction was demonstrated in Syrian hamster embryo fibroblasts and was found to be induced in cells exposed to neutrons administered at low (0.5 cGy/min) and at high dose rate (12 cGy/min). The induction of transcription from the LTR of HIV was demonstrated in HeLa cells bearing a transfected construct of the chloramphenicol acetyl transferase (CAT) gene driven by the HIV-LTR promoter. Measures of CAT activity and CAT transcripts following irradiation demonstrated an unresponsiveness to γ rays over a broad range of doses. Twofold induction of the HIV-LTR was detected following neutron exposure (48 cGy) administered at low (0.5 cGy/min) but not high (12 cGy/min) dose rates. Ultraviolet-mediated HIV-LTR induction was inhibited by low-dose-rate neutron exposure

  15. Acyclovir and Transmission of HIV-1 from Persons Infected with HIV-1 and HSV-2

    Science.gov (United States)

    Celum, Connie; Wald, Anna; Lingappa, Jairam R.; Magaret, Amalia S.; Wang, Richard S.; Mugo, Nelly; Mujugira, Andrew; Baeten, Jared M.; Mullins, James I.; Hughes, James P.; Bukusi, Elizabeth A.; Cohen, Craig R.; Katabira, Elly; Ronald, Allan; Kiarie, James; Farquhar, Carey; Stewart, Grace John; Makhema, Joseph; Essex, Myron; Were, Edwin; Fife, Kenneth H.; de Bruyn, Guy; Gray, Glenda E.; McIntyre, James A.; Manongi, Rachel; Kapiga, Saidi; Coetzee, David; Allen, Susan; Inambao, Mubiana; Kayitenkore, Kayitesi; Karita, Etienne; Kanweka, William; Delany, Sinead; Rees, Helen; Vwalika, Bellington; Stevens, Wendy; Campbell, Mary S.; Thomas, Katherine K.; Coombs, Robert W.; Morrow, Rhoda; Whittington, William L.H.; McElrath, M. Juliana; Barnes, Linda; Ridzon, Renee; Corey, Lawrence

    2010-01-01

    BACKGROUND Most persons who are infected with human immunodeficiency virus type 1 (HIV-1) are also infected with herpes simplex virus type 2 (HSV-2), which is frequently reactivated and is associated with increased plasma and genital levels of HIV-1. Therapy to suppress HSV-2 reduces the frequency of reactivation of HSV-2 as well as HIV-1 levels, suggesting that suppression of HSV-2 may reduce the risk of transmission of HIV-1. METHODS We conducted a randomized, placebo-controlled trial of suppressive therapy for HSV-2 (acyclovir at a dose of 400 mg orally twice daily) in couples in which only one of the partners was seropositive for HIV-1 (CD4 count, ≥250 cells per cubic millimeter) and that partner was also infected with HSV-2 and was not taking antiretroviral therapy at the time of enrollment. The primary end point was transmission of HIV-1 to the partner who was not initially infected with HIV-1; linkage of transmissions was assessed by means of genetic sequencing of viruses. RESULTS A total of 3408 couples were enrolled at 14 sites in Africa. Of the partners who were infected with HIV-1, 68% were women, and the baseline median CD4 count was 462 cells per cubic millimeter. Of 132 HIV-1 seroconversions that occurred after randomization (an incidence of 2.7 per 100 person-years), 84 were linked within couples by viral sequencing: 41 in the acyclovir group and 43 in the placebo group (hazard ratio with acyclovir, 0.92, 95% confidence interval [CI], 0.60 to 1.41; P = 0.69). Suppression with acyclovir reduced the mean plasma concentration of HIV-1 by 0.25 log10 copies per milliliter (95% CI, 0.22 to 0.29; P<0.001) and the occurrence of HSV-2–positive genital ulcers by 73% (risk ratio, 0.27; 95% CI, 0.20 to 0.36; P<0.001). A total of 92% of the partners infected with HIV-1 and 84% of the partners not infected with HIV-1 remained in the study for 24 months. The level of adherence to the dispensed study drug was 96%. No serious adverse events related to acyclovir

  16. Oligodendrocyte Injury and Pathogenesis of HIV-1-Associated Neurocognitive Disorders

    Directory of Open Access Journals (Sweden)

    Han Liu

    2016-07-01

    Full Text Available Oligodendrocytes wrap neuronal axons to form myelin, an insulating sheath which is essential for nervous impulse conduction along axons. Axonal myelination is highly regulated by neuronal and astrocytic signals and the maintenance of myelin sheaths is a very complex process. Oligodendrocyte damage can cause axonal demyelination and neuronal injury, leading to neurological disorders. Demyelination in the cerebrum may produce cognitive impairment in a variety of neurological disorders, including human immunodeficiency virus type one (HIV-1-associated neurocognitive disorders (HAND. Although the combined antiretroviral therapy has markedly reduced the incidence of HIV-1-associated dementia, a severe form of HAND, milder forms of HAND remain prevalent even when the peripheral viral load is well controlled. HAND manifests as a subcortical dementia with damage in the brain white matter (e.g., corpus callosum, which consists of myelinated axonal fibers. How HIV-1 brain infection causes myelin injury and resultant white matter damage is an interesting area of current HIV research. In this review, we tentatively address recent progress on oligodendrocyte dysregulation and HAND pathogenesis.

  17. HIV-1 genetic diversity and its distribution characteristics among newly diagnosed HIV-1 individuals in Hebei province, China.

    Science.gov (United States)

    Lu, Xinli; Zhao, Cuiying; Wang, Wei; Nie, Chenxi; Zhang, Yuqi; Zhao, Hongru; Chen, Suliang; Cui, Ze

    2016-01-01

    Since the first HIV-1 case in 1989, Hebei province has presented a clearly rising trend of HIV-1 prevalence, and HIV-1 genetic diversity has become the vital barrier to HIV prevention and control in this area. To obtain detailed information of HIV-1 spread in different populations and in different areas of Hebei, a cross-sectional HIV-1 molecular epidemiological investigation was performed across the province. Blood samples of 154 newly diagnosed HIV-1 individuals were collected from ten prefectures in Hebei using stratified sampling. Partial gag and env genes were amplified and sequenced. HIV-1 genotypes were identified by phylogenetic tree analyses. Among the 139 subjects genotyped, six HIV-1 subtypes were identified successfully, including subtype B (41.0 %), CRF01_AE (40.3 %), CRF07_BC (11.5 %), CRF08_BC (4.3 %), unique recombinant forms (URFs) (1.4 %) and subtype C (1.4 %). Subtype B was identified as the most frequent subtype. Two URF recombination patterns were the same as CRF01_AE/B. HIV-1 genotype distribution showed a significant statistical difference in different demographic characteristics, such as source (P  0.05). The differences in HIV-1 genotype distribution were closely associated with transmission routes. Particularly, all six subtype strains were found in heterosexuals, showing that HIV-1 has spread from the high-risk populations to the general populations in Hebei, China. In addition, CRF01_AE instead of subtype B has become the major strain of HIV-1 infection among homosexuals. Our study revealed HIV-1 evolution and genotype distribution by investigating newly diagnosed HIV-1 individuals in Hebei, China. This study provides important information to enhance the strategic plan for HIV prevention and control in China.

  18. Cloning and heterologous expression of a hydrophobin gene Ltr.hyd from the tiger milk mushroom Lentinus tuber-regium in yeast-like cells of Tremella fuciformis

    Directory of Open Access Journals (Sweden)

    Dongmei Liu

    2018-03-01

    Full Text Available Background: Hydrophobins are small proteins secreted by filamentous fungi, which show a highly surface activity. Because of the signally self-assembling abilities and surface activities, hydrophobins were considered as candidates in many aspects, for example, stabilizing foams and emulsions in food products. Lentinus tuber-regium, known as tiger milk mushroom, is both an edible and medicinal sclerotium-producing mushroom. Up to now, the hydrophobins of L. tuber-regium have not been identified. Results: In this paper, a Class I hydrophobin gene, Ltr.hyd, was cloned from L. tuber-regium and expressed in the yeast-like cells of Tremella fuciformis mediated by Agrobacterium tumefaciens. The expression vector pGEH-GH was under the control of T. fuciformis glyceraldehyde-3-phosphate dehydrogenase gene (gpd promoter. The integration of Ltr.hyd into the genome of T. fuciformis was confirmed by PCR, Southern blot, fluorescence observation and quantitative real-time PCR (qRT-PCR. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE demonstrated that recombinant hydrophobin rLtr.HYD with an expected molecular mass of 13 kDa was extracted. The yield of rLtr.HYD was 0.66 mg/g dry weight. The emulsifying activity of rLtr.HYD was better than the typical food emulsifiers sodium caseinate and Tween 20. Conclusions: We evaluated the emulsifying property of hydrophobin Ltr.HYD, which can be potentially used as a food emulsifier. Keywords: Agrobacterium tumefaciens, Emulsifier, Expression vector, Filamentous fungi, Gel electrophoresis, Glyceraldehyde-3-phosphate dehydrogenase, Heterogenous expression, Hydrophobin, Quantitative real-time PCR, Southern blot, Surface activity

  19. Interactions Between HIV-1 Gag and Viral RNA Genome Enhance Virion Assembly

    DEFF Research Database (Denmark)

    Dilley, Kari A; Nikolaitchik, Olga A; Galli, Andrea

    2017-01-01

    between Gag and viral RNA are required for the enhancement of particle production. Taken together, these studies are consistent with our previous hypothesis that specific dimeric viral RNA:Gag interactions are the nucleation event of infectious virion assembly, ensuring that one RNA dimer is packaged......Most HIV-1 virions contain two copies of full-length viral RNA, indicating that genome packaging is efficient and tightly regulated. However, the structural protein Gag is the only component required for the assembly of noninfectious virus-like particles and the viral RNA is dispensable...... in this process. The mechanism that allows HIV-1 to achieve such high efficiency of genome packaging when a packageable viral RNA is not required for virus assembly is currently unknown. In this report, we examined the role of HIV-1 RNA in virus assembly and found that packageable HIV-1 RNA enhances particle...

  20. Two cis-acting elements responsible for posttranscriptional trans-regulation of gene expression of human T-cell leukemia virus type I

    International Nuclear Information System (INIS)

    Seiki, Motoharu; Inoue, Junichiro; Hidaka, Makoto; Yoshida, Mitsuaki

    1988-01-01

    The pX sequence of human T-cell leukemia virus type I codes for two nuclear proteins, p40 tax and p27 rex and a cytoplasmic protein, p21 X-III . p40 tax activates transcription from the long terminal repeat (LTR), whereas p27 rex modulates posttranscriptional processing to accumulate gag and env mRNAs that retain intron sequences. In this paper, the authors identify two cis-acting sequence elements needed for regulation by p27 rex : a 5' splice signal and a specific sequence in the 3' LTR. These two sequence elements are sufficient for regulation by p27 rex ; expression of a cellular gene (metallothionein I) became sensitive to rex regulation when the LTR was inserted at the 3' end of this gene. The requirement for these two elements suggests and unusual regulatory mechanism of RNA processing in the nucleus

  1. Selective elimination of HIV-1-infected cells by Env-directed, HIV-1-based virus-like particles

    International Nuclear Information System (INIS)

    Peretti, Silvia; Schiavoni, Ilaria; Pugliese, Katherina; Federico, Maurizio

    2006-01-01

    We recently showed that both replicating and resting cells cultivated with ganciclovir (GCV) were killed when challenged with vesicular stomatitis virus G glycoprotein pseudotyped HIV-1-based virus-like particles (VLPs) carrying the Nef7 (i.e., an HIV-1 Nef mutant incorporating in virions at high levels)/herpes simplex virus-1 thymidine kinase (HSV-TK) fusion product. On this basis, a novel anti-HIV therapeutic approach based on Nef7/TK VLPs expressing X4 or R5 HIV cell receptor complexes has been attempted. We here report that (CD4-CXCR4) and (CD4-CCR5) Nef7-based VLPs efficiently enter cells infected by X4- or R5-tropic HIV-1 strains, respectively. Importantly, the delivery of the VLP-associated Nef7/TK led to cell death upon GCV treatment. Of interest, VLPs were effective also against non-replicating, HIV-1-infected primary human monocyte-derived macrophages. HIV-targeted VLPs represent a promising candidate for the treatment of persistently HIV-1-infected cells that are part of virus reservoirs resistant to HAART therapies

  2. Resveratrol Reactivates Latent HIV through Increasing Histone Acetylation and Activating Heat Shock Factor 1.

    Science.gov (United States)

    Zeng, Xiaoyun; Pan, Xiaoyan; Xu, Xinfeng; Lin, Jian; Que, Fuchang; Tian, Yuanxin; Li, Lin; Liu, Shuwen

    2017-06-07

    The persistence of latent HIV reservoirs presents a significant challenge to viral eradication. Effective latency reversing agents (LRAs) based on "shock and kill" strategy are urgently needed. The natural phytoalexin resveratrol has been demonstrated to enhance HIV gene expression, although its mechanism remains unclear. In this study, we demonstrated that resveratrol was able to reactivate latent HIV without global T cell activation in vitro. Mode of action studies showed resveratrol-mediated reactivation from latency did not involve the activation of silent mating type information regulation 2 homologue 1 (SIRT1), which belonged to class-3 histone deacetylase (HDAC). However, latent HIV was reactivated by resveratrol mediated through increasing histone acetylation and activation of heat shock factor 1 (HSF1). Additionally, synergistic activation of the latent HIV reservoirs was observed under cotreatment with resveratrol and conventional LRAs. Collectively, this research reveals that resveratrol is a natural LRA and shows promise for HIV therapy.

  3. HIV-1-Specific IgA Monoclonal Antibodies from an HIV-1 Vaccinee Mediate Galactosylceramide Blocking and Phagocytosis

    Science.gov (United States)

    2018-01-01

    ABSTRACT Vaccine-elicited humoral immune responses comprise an array of antibody forms and specificities, with only a fraction contributing to protective host immunity. Elucidation of antibody effector functions responsible for protective immunity against human immunodeficiency virus type 1 (HIV-1) acquisition is a major goal for the HIV-1 vaccine field. Immunoglobulin A (IgA) is an important part of the host defense against pathogens; however, little is known about the role of vaccine-elicited IgA and its capacity to mediate antiviral functions. To identify the antiviral functions of HIV-1-specific IgA elicited by vaccination, we cloned HIV-1 envelope-specific IgA monoclonal antibodies (MAbs) by memory B cell cultures from peripheral blood mononuclear cells from an RV144 vaccinee and produced two IgA clonal cell lines (HG129 and HG130) producing native, nonrecombinant IgA MAbs. The HG129 and HG130 MAbs mediated phagocytosis by monocytes, and HG129 blocked HIV-1 Env glycoprotein binding to galactosylceramide, an alternative HIV-1 receptor. These findings elucidate potential antiviral functions of vaccine-elicited HIV-1 envelope-specific IgA that may act to block HIV-1 acquisition at the portal of entry by preventing HIV-1 binding to galactosylceramide and mediating antibody Fc receptor-mediated virion phagocytosis. Furthermore, these findings highlight the complex and diverse interactions of vaccine-elicited IgA with pathogens that depend on IgA fine specificity and form (e.g., multimeric or monomeric) in the systemic circulation and mucosal compartments. IMPORTANCE Host-pathogen interactions in vivo involve numerous immune mechanisms that can lead to pathogen clearance. Understanding the nature of antiviral immune mechanisms can inform the design of efficacious HIV-1 vaccine strategies. Evidence suggests that both neutralizing and nonneutralizing antibodies can mediate some protection against HIV in animal models. Although numerous studies have characterized the

  4. Identifying HIV-1 dual infections

    Directory of Open Access Journals (Sweden)

    Cornelissen Marion

    2007-09-01

    Full Text Available Abstract Transmission of human immunodeficiency virus (HIV is no exception to the phenomenon that a second, productive infection with another strain of the same virus is feasible. Experiments with RNA viruses have suggested that both coinfections (simultaneous infection with two strains of a virus and superinfections (second infection after a specific immune response to the first infecting strain has developed can result in increased fitness of the viral population. Concerns about dual infections with HIV are increasing. First, the frequent detection of superinfections seems to indicate that it will be difficult to develop a prophylactic vaccine. Second, HIV-1 superinfections have been associated with accelerated disease progression, although this is not true for all persons. In fact, superinfections have even been detected in persons controlling their HIV infections without antiretroviral therapy. Third, dual infections can give rise to recombinant viruses, which are increasingly found in the HIV-1 epidemic. Recombinants could have increased fitness over the parental strains, as in vitro models suggest, and could exhibit increased pathogenicity. Multiple drug resistant (MDR strains could recombine to produce a pan-resistant, transmittable virus. We will describe in this review what is presently known about super- and re-infection among ambient viral infections, as well as the first cases of HIV-1 superinfection, including HIV-1 triple infections. The clinical implications, the impact of the immune system, and the effect of anti-retroviral therapy will be covered, as will as the timing of HIV superinfection. The methods used to detect HIV-1 dual infections will be discussed in detail. To increase the likelihood of detecting a dual HIV-1 infection, pre-selection of patients can be done by serotyping, heteroduplex mobility assays (HMA, counting the degenerate base codes in the HIV-1 genotyping sequence, or surveying unexpected increases in the

  5. Candidate Microbicides Block HIV-1 Infection of Human Immature Langerhans Cells within Epithelial Tissue Explants

    Science.gov (United States)

    Kawamura, Tatsuyoshi; Cohen, Sandra S.; Borris, Debra L.; Aquilino, Elisabeth A.; Glushakova, Svetlana; Margolis, Leonid B.; Orenstein, Jan M.; Offord, Robin E.; Neurath, A. Robert; Blauvelt, Andrew

    2000-01-01

    Initial biologic events that underlie sexual transmission of HIV-1 are poorly understood. To model these events, we exposed human immature Langerhans cells (LCs) within epithelial tissue explants to two primary and two laboratory-adapted HIV-1 isolates. We detected HIV-1Ba-L infection in single LCs that spontaneously emigrated from explants by flow cytometry (median of infected LCs = 0.52%, range = 0.08–4.77%). HIV-1–infected LCs downregulated surface CD4 and CD83, whereas MHC class II, CD80, and CD86 were unchanged. For all HIV-1 strains tested, emigrated LCs were critical in establishing high levels of infection (0.11 μg HIV-1 p24 per milliliter) in cocultured autologous or allogeneic T cells. HIV-1Ba-L (an R5 HIV-1 strain) more efficiently infected LC–T cell cocultures when compared with HIV-1IIIB (an X4 HIV-1 strain). Interestingly, pretreatment of explants with either aminooxypentane-RANTES (regulated upon activation, normal T cell expressed and secreted) or cellulose acetate phthalate (potential microbicides) blocked HIV-1 infection of LCs and subsequent T cell infection in a dose-dependent manner. In summary, we document HIV-1 infection in single LCs after exposure to virus within epithelial tissue, demonstrate that relatively low numbers of these cells are capable of inducing high levels of infection in cocultured T cells, and provide a useful explant model for testing of agents designed to block sexual transmission of HIV-1. PMID:11085750

  6. Macrophage Resistance to HIV-1 Infection Is Enhanced by the Neuropeptides VIP and PACAP

    Science.gov (United States)

    Temerozo, Jairo R.; Joaquim, Rafael; Regis, Eduardo G.; Savino, Wilson; Bou-Habib, Dumith Chequer

    2013-01-01

    It is well established that host factors can modulate HIV-1 replication in macrophages, critical cells in the pathogenesis of HIV-1 infection due to their ability to continuously produce virus. The neuropeptides VIP and PACAP induce well-characterized effects on macrophages through binding to the G protein-coupled receptors VPAC1, VPAC2 and PAC1, but their influence on HIV-1 production by these cells has not been established. Here, we describe that VIP and PACAP reduce macrophage production of HIV-1, acting in a synergistic or additive manner to decrease viral growth. Using receptor antagonists, we detected that the HIV-1 inhibition promoted by VIP is dependent on its ligation to VPAC1/2, whereas PACAP decreases HIV-1 growth via activation of the VPAC1/2 and PAC1 receptors. Specific agonists of VPAC2 or PAC1 decrease macrophage production of HIV-1, whereas sole activation of VPAC1 enhances viral growth. However, the combination of specific agonists mimicking the receptor preference of the natural neuropeptides reproduces the ability of VIP and PACAP to increase macrophage resistance to HIV-1 replication. VIP and PACAP up-regulated macrophage secretion of the β-chemokines CCL3 and CCL5 and the cytokine IL-10, whose neutralization reversed the neuropeptide-induced inhibition of HIV-1 replication. Our results suggest that VIP and PACAP and the receptors VPAC2 and PAC1 could be used as targets for developing alternative therapeutic strategies for HIV-1 infection. PMID:23818986

  7. HIV-1 Latency in Monocytes/Macrophages

    Directory of Open Access Journals (Sweden)

    Amit Kumar

    2014-04-01

    Full Text Available Human immunodeficiency virus type 1 (HIV-1 targets CD4+ T cells and cells of the monocyte/macrophage lineage. HIV pathogenesis is characterized by the depletion of T lymphocytes and by the presence of a population of cells in which latency has been established called the HIV-1 reservoir. Highly active antiretroviral therapy (HAART has significantly improved the life of HIV-1 infected patients. However, complete eradication of HIV-1 from infected individuals is not possible without targeting latent sources of infection. HIV-1 establishes latent infection in resting CD4+ T cells and findings indicate that latency can also be established in the cells of monocyte/macrophage lineage. Monocyte/macrophage lineage includes among others, monocytes, macrophages and brain resident macrophages. These cells are relatively more resistant to apoptosis induced by HIV-1, thus are important stable hideouts of the virus. Much effort has been made in the direction of eliminating HIV-1 resting CD4+ T-cell reservoirs. However, it is impossible to achieve a cure for HIV-1 without considering these neglected latent reservoirs, the cells of monocyte/macrophage lineage. In this review we will describe our current understanding of the mechanism of latency in monocyte/macrophage lineage and how such cells can be specifically eliminated from the infected host.

  8. DJ1 Expression Downregulates in Neuroblastoma Cells (SK-N-MC Chronically Exposed to HIV-1 and Cocaine.

    Directory of Open Access Journals (Sweden)

    Upal eRoy

    2015-07-01

    Full Text Available Background: HIV-associated neurological disorder (HAND has long been recognized as a consequence of Human Immunodeficiency Virus (HIV infection in the brain. The pathology of HAND gets more complicated with the recreational drug use such as cocaine. Recent studies have suggested multiple genetic influences involved in the pathology of addiction and HAND but only a fraction of the entire genetic risk has been investigated so far. In this regard, role of DJ1 protein (a gene linked to autosomal recessive early-onset Parkinson’s disease in regulating dopamine transmission and reactive oxygen species (ROS production in neuronal cells will be worth investigating in HIV-1 and cocaine exposed microenvironment. Being a very abundant protein in the brain, DJ1 could serve as a potential marker for early detection of HIV-1 and/or cocaine related neurological disorder.Methods: In vitro analysis was done to observe the effect of HIV-1 and/or cocaine on DJ1 protein expression in neuroblastoma cells (SK-N-MC. Gene expression and protein analysis of DJ1 was done on the HIV infected and/or cocaine treated SK-N-MC and compared to untreated cells using real time PCR, Western Blot and flow cytometry.Results: Gene expression and protein analysis indicated that there was a significant decrease in DJ1 expression in SK-N-MC chronically exposed to HIV-1 and/or cocaine.Conclusion: This is the first study to establish that DJ1 expression level in the neuronal cells significantly decreased in presence of HIV-1and/or cocaine indicating oxidative stress level of dopamine neurons.

  9. Development of an epitope-based HIV-1 vaccine strategy from HIV-1 lipopeptide to dendritic-based vaccines.

    Science.gov (United States)

    Surenaud, Mathieu; Lacabaratz, Christine; Zurawski, Gérard; Lévy, Yves; Lelièvre, Jean-Daniel

    2017-10-01

    Development of a safe, effective and globally affordable Human Immunodeficiency Virus strain 1 (HIV-1) vaccine offers the best hope for future control of the HIV-1 pandemic. However, with the exception of the recent RV144 trial, which elicited a modest level of protection against infection, no vaccine candidate has shown efficacy in preventing HIV-1 infection or in controlling virus replication in humans. There is also a great need for a successful immunotherapeutic vaccine since combination antiretroviral therapy (cART) does not eliminate the reservoir of HIV-infected cells. But to date, no vaccine candidate has proven to significantly alter the natural history of an individual with HIV-1 infection. Areas covered: For over 25 years, the ANRS (France Recherche Nord&Sud Sida-HIV hépatites) has been committed to an original program combining basic science and clinical research developing an epitope-based vaccine strategy to induce a multiepitopic cellular response against HIV-1. This review describes the evolution of concepts, based on strategies using HIV-1 lipopeptides towards the use of dendritic cell (DC) manipulation. Expert commentary: Understanding the crucial role of DCs in immune responses allowed moving from the non-specific administration of HIV-1 sequences with lipopeptides to DC-based vaccines. These DC-targeting strategies should improve HIV-1 vaccine efficacy.

  10. HIV-1 phylogenetic analysis shows HIV-1 transits through the meninges to brain and peripheral tissues.

    Science.gov (United States)

    Lamers, Susanna L; Gray, Rebecca R; Salemi, Marco; Huysentruyt, Leanne C; McGrath, Michael S

    2011-01-01

    Brain infection by the human immunodeficiency virus type 1 (HIV-1) has been investigated in many reports with a variety of conclusions concerning the time of entry and degree of viral compartmentalization. To address these diverse findings, we sequenced HIV-1 gp120 clones from a wide range of brain, peripheral and meningeal tissues from five patients who died from several HIV-1 associated disease pathologies. High-resolution phylogenetic analysis confirmed previous studies that showed a significant degree of compartmentalization in brain and peripheral tissue subpopulations. Some intermixing between the HIV-1 subpopulations was evident, especially in patients that died from pathologies other than HIV-associated dementia. Interestingly, the major tissue harboring virus from both the brain and peripheral tissues was the meninges. These results show that (1) HIV-1 is clearly capable of migrating out of the brain, (2) the meninges are the most likely primary transport tissues, and (3) infected brain macrophages comprise an important HIV reservoir during highly active antiretroviral therapy. Copyright © 2010 Elsevier B.V. All rights reserved.

  11. Colon dysregulation in methamphetamine self-administering HIV-1 transgenic rats.

    Directory of Open Access Journals (Sweden)

    Amanda L Persons

    Full Text Available The integrity and function of the gut is impaired in HIV-infected individuals, and gut pathogenesis may play a role in several HIV-associated disorders. Methamphetamine is a popular illicit drug abused by HIV-infected individuals. However, the effect of methamphetamine on the gut and its potential to exacerbate HIV-associated gut pathology is not known. To shed light on this scenario, we evaluated colon barrier pathology in a rat model of the human comorbid condition. Intestinal barrier integrity and permeability were assessed in drug-naïve Fischer 344 HIV-1 transgenic (Tg and non-Tg rats, and in Tg and non-Tg rats instrumented with jugular cannulae trained to self-administer methamphetamine or serving as saline-yoked controls. Intestinal permeability was determined by measuring the urine content of orally gavaged sugars. Intestinal barrier integrity was evaluated by immunoblotting or immunofluorescence of colon claudin-1 and zonula occludens-1 (ZO-1, two major tight junction proteins that regulate gut epithelial paracellular permeability. Both non-Tg and Tg rats self-administered moderate amounts of methamphetamine. These amounts were sufficient to increase colon permeability, reduce protein level of claudin-1, and reduce claudin-1 and ZO-1 immunofluorescence in Tg rats relative to non-Tg rats. Methamphetamine decreased tight junction immunofluorescence in non-Tg rats, with a similar, but non-significant trend observed in Tg rats. However, the effect of methamphetamine on tight junction proteins was subthreshold to gut leakiness. These findings reveal that both HIV-1 proteins and methamphetamine alter colon barrier integrity, and indicate that the gut may be a pathogenic site for these insults.

  12. Colon dysregulation in methamphetamine self-administering HIV-1 transgenic rats.

    Science.gov (United States)

    Persons, Amanda L; Bradaric, Brinda D; Dodiya, Hemraj B; Ohene-Nyako, Michael; Forsyth, Christopher B; Keshavarzian, Ali; Shaikh, Maliha; Napier, T Celeste

    2018-01-01

    The integrity and function of the gut is impaired in HIV-infected individuals, and gut pathogenesis may play a role in several HIV-associated disorders. Methamphetamine is a popular illicit drug abused by HIV-infected individuals. However, the effect of methamphetamine on the gut and its potential to exacerbate HIV-associated gut pathology is not known. To shed light on this scenario, we evaluated colon barrier pathology in a rat model of the human comorbid condition. Intestinal barrier integrity and permeability were assessed in drug-naïve Fischer 344 HIV-1 transgenic (Tg) and non-Tg rats, and in Tg and non-Tg rats instrumented with jugular cannulae trained to self-administer methamphetamine or serving as saline-yoked controls. Intestinal permeability was determined by measuring the urine content of orally gavaged sugars. Intestinal barrier integrity was evaluated by immunoblotting or immunofluorescence of colon claudin-1 and zonula occludens-1 (ZO-1), two major tight junction proteins that regulate gut epithelial paracellular permeability. Both non-Tg and Tg rats self-administered moderate amounts of methamphetamine. These amounts were sufficient to increase colon permeability, reduce protein level of claudin-1, and reduce claudin-1 and ZO-1 immunofluorescence in Tg rats relative to non-Tg rats. Methamphetamine decreased tight junction immunofluorescence in non-Tg rats, with a similar, but non-significant trend observed in Tg rats. However, the effect of methamphetamine on tight junction proteins was subthreshold to gut leakiness. These findings reveal that both HIV-1 proteins and methamphetamine alter colon barrier integrity, and indicate that the gut may be a pathogenic site for these insults.

  13. The effect of antiretroviral intensification with dolutegravir on residual virus replication in HIV-infected individuals: a randomised, placebo-controlled, double-blind trial.

    Science.gov (United States)

    Rasmussen, Thomas A; McMahon, James H; Chang, J Judy; Audsley, Jennifer; Rhodes, Ajantha; Tennakoon, Surekha; Dantanarayana, Ashanti; Spelman, Tim; Schmidt, Tina; Kent, Stephen J; Morcilla, Vincent; Palmer, Sarah; Elliott, Julian H; Lewin, Sharon R

    2018-04-06

    Whether ongoing virus replication occurs in HIV-infected individuals on antiretroviral therapy (ART) is unclear; therefore, whether residual virus replication is a barrier to achieving a cure for HIV is also unknown. We aimed to establish whether ART intensification with dolutegravir would reveal or affect residual virus replication in HIV-infected individuals on suppressive treatment. In this randomised, placebo-controlled, double-blind trial, we enrolled HIV-infected adults (aged 18 years and older) receiving combination ART (at least three agents) for at least 3 years from the Alfred Hospital and Melbourne Sexual Health Centre, Melbourne, VIC, Australia. Eligible participants had fewer than 50 copies per mL HIV-1 plasma RNA for more than 3 years and fewer than 20 copies per mL at screening and two CD4 counts higher than 350 cells per μL in the previous 24 months including screening. Participants were randomly assigned (1:1) to receive 50 mg oral dolutegravir or placebo once a day for 56 days in addition to background ART. Follow-up was done at days 1, 3, 7, 14, 28, 56, and 84. The primary outcome was the change from baseline in frequency of 2-long terminal repeat (2-LTR) circles in peripheral blood CD4 cells at day 7. This trial is registered with ClinicalTrials.gov, number NCT02500446. Between Sept 21, 2015, and Sept 19, 2016, 46 individuals were screened for inclusion. 40 were eligible for inclusion and were randomly assigned to the dolutegravir (n=21) or placebo group (n=19). All enrolled participants completed the study procedures and no individuals were lost to follow up. All participants were on suppressive ART with 12% receiving protease inhibitors and the others non-nucleoside reverse transcriptase inhibitors. Median 2-LTR circles fold-change from baseline to day 7 was -0·17 (IQR -0·90 to 0·90) in the dolutegravir group and -0·26 (-1·00 to 1·17) in the placebo group (p=0·17). The addition of dolutegravir to pre-existing ART regimens was safe and

  14. The thermodynamics of Pr55Gag-RNA interaction regulate the assembly of HIV.

    Directory of Open Access Journals (Sweden)

    Hanumant S Tanwar

    2017-02-01

    Full Text Available The interactions that occur during HIV Pr55Gag oligomerization and genomic RNA packaging are essential elements that facilitate HIV assembly. However, mechanistic details of these interactions are not clearly defined. Here, we overcome previous limitations in producing large quantities of full-length recombinant Pr55Gag that is required for isothermal titration calorimetry (ITC studies, and we have revealed the thermodynamic properties of HIV assembly for the first time. Thermodynamic analysis showed that the binding between RNA and HIV Pr55Gag is an energetically favourable reaction (ΔG<0 that is further enhanced by the oligomerization of Pr55Gag. The change in enthalpy (ΔH widens sequentially from: (1 Pr55Gag-Psi RNA binding during HIV genome selection; to (2 Pr55Gag-Guanosine Uridine (GU-containing RNA binding in cytoplasm/plasma membrane; and then to (3 Pr55Gag-Adenosine(A-containing RNA binding in immature HIV. These data imply the stepwise increments of heat being released during HIV biogenesis may help to facilitate the process of viral assembly. By mimicking the interactions between A-containing RNA and oligomeric Pr55Gag in immature HIV, it was noted that a p6 domain truncated Pr50Gag Δp6 is less efficient than full-length Pr55Gag in this thermodynamic process. These data suggest a potential unknown role of p6 in Pr55Gag-Pr55Gag oligomerization and/or Pr55Gag-RNA interaction during HIV assembly. Our data provide direct evidence on how nucleic acid sequences and the oligomeric state of Pr55Gag regulate HIV assembly.

  15. Class 1-Selective Histone Deacetylase (HDAC) Inhibitors Enhance HIV Latency Reversal while Preserving the Activity of HDAC Isoforms Necessary for Maximal HIV Gene Expression.

    Science.gov (United States)

    Zaikos, Thomas D; Painter, Mark M; Sebastian Kettinger, Nadia T; Terry, Valeri H; Collins, Kathleen L

    2018-03-15

    Combinations of drugs that affect distinct mechanisms of HIV latency aim to induce robust latency reversal leading to cytopathicity and elimination of the persistent HIV reservoir. Thus far, attempts have focused on combinations of protein kinase C (PKC) agonists and pan-histone deacetylase inhibitors (HDIs) despite the knowledge that HIV gene expression is regulated by class 1 histone deacetylases. We hypothesized that class 1-selective HDIs would promote more robust HIV latency reversal in combination with a PKC agonist than pan-HDIs because they preserve the activity of proviral factors regulated by non-class 1 histone deacetylases. Here, we show that class 1-selective agents used alone or with the PKC agonist bryostatin-1 induced more HIV protein expression per infected cell. In addition, the combination of entinostat and bryostatin-1 induced viral outgrowth, whereas bryostatin-1 combinations with pan-HDIs did not. When class 1-selective HDIs were used in combination with pan-HDIs, the amount of viral protein expression and virus outgrowth resembled that of pan-HDIs alone, suggesting that pan-HDIs inhibit robust gene expression induced by class 1-selective HDIs. Consistent with this, pan-HDI-containing combinations reduced the activity of NF-κB and Hsp90, two cellular factors necessary for potent HIV protein expression, but did not significantly reduce overall cell viability. An assessment of viral clearance from in vitro cultures indicated that maximal protein expression induced by class 1-selective HDI treatment was crucial for reservoir clearance. These findings elucidate the limitations of current approaches and provide a path toward more effective strategies to eliminate the HIV reservoir. IMPORTANCE Despite effective antiretroviral therapy, HIV evades eradication in a latent form that is not affected by currently available drug regimens. Pharmacologic latency reversal that leads to death of cellular reservoirs has been proposed as a strategy for

  16. A super-family of transcriptional activators regulates bacteriophage packaging and lysis in Gram-positive bacteria

    Science.gov (United States)

    Quiles-Puchalt, Nuria; Tormo-Más, María Ángeles; Campoy, Susana; Toledo-Arana, Alejandro; Monedero, Vicente; Lasa, Íñigo; Novick, Richard P.; Christie, Gail E.; Penadés, José R.

    2013-01-01

    The propagation of bacteriophages and other mobile genetic elements requires exploitation of the phage mechanisms involved in virion assembly and DNA packaging. Here, we identified and characterized four different families of phage-encoded proteins that function as activators required for transcription of the late operons (morphogenetic and lysis genes) in a large group of phages infecting Gram-positive bacteria. These regulators constitute a super-family of proteins, here named late transcriptional regulators (Ltr), which share common structural, biochemical and functional characteristics and are unique to this group of phages. They are all small basic proteins, encoded by genes present at the end of the early gene cluster in their respective phage genomes and expressed under cI repressor control. To control expression of the late operon, the Ltr proteins bind to a DNA repeat region situated upstream of the terS gene, activating its transcription. This involves the C-terminal part of the Ltr proteins, which control specificity for the DNA repeat region. Finally, we show that the Ltr proteins are the only phage-encoded proteins required for the activation of the packaging and lysis modules. In summary, we provide evidence that phage packaging and lysis is a conserved mechanism in Siphoviridae infecting a wide variety of Gram-positive bacteria. PMID:23771138

  17. New Highly Sensitive Real-Time PCR Assay for HIV-2 Group A and Group B DNA Quantification.

    Science.gov (United States)

    Bertine, Mélanie; Gueudin, Marie; Mélard, Adeline; Damond, Florence; Descamps, Diane; Matheron, Sophie; Collin, Fidéline; Rouzioux, Christine; Plantier, Jean-Christophe; Avettand-Fenoel, Véronique

    2017-09-01

    HIV-2 infection is characterized by a very low replication rate in most cases and low progression. This necessitates an approach to patient monitoring that differs from that for HIV-1 infection. Here, a new highly specific and sensitive method for HIV-2 DNA quantification was developed. The new test is based on quantitative real-time PCR targeting the long terminal repeat (LTR) and gag regions and using an internal control. Analytical performance was determined in three laboratories, and clinical performance was determined on blood samples from 63 patients infected with HIV-2 group A ( n = 35) or group B ( n = 28). The specificity was 100%. The 95% limit of detection was three copies/PCR and the limit of quantification was six copies/PCR. The within-run coefficients of variation were between 1.03% at 3.78 log 10 copies/PCR and 27.02% at 0.78 log 10 copies/PCR. The between-run coefficient of variation was 5.10%. Both manual and automated nucleic acid extraction methods were validated. HIV-2 DNA loads were detectable in blood cells from all 63 patients. When HIV-2 DNA was quantifiable, median loads were significantly higher in antiretroviral-treated than in naive patients and were similar for groups A and B. HIV-2 DNA load was correlated with HIV-2 RNA load ( r = 0.68; 95% confidence interval [CI], 0.4 to 0.8; P < 0.0001). Our data show that this new assay is highly sensitive and quantifies the two main HIV-2 groups, making it useful for the diagnosis of HIV-2 infection and for pathogenesis studies on HIV-2 reservoirs. Copyright © 2017 American Society for Microbiology.

  18. Nup153 and Nup98 bind the HIV-1 core and contribute to the early steps of HIV-1 replication

    Energy Technology Data Exchange (ETDEWEB)

    Di Nunzio, Francesca, E-mail: francesca.di-nunzio@pasteur.fr [Molecular Virology and Vaccinology unit, CNRS URA 3015, Department of Virology, Institut Pasteur, 25-28 rue du Dr. Roux, 75015 Paris (France); Fricke, Thomas [Department of Microbiology and Immunology, Albert Einstein College of Medicine Bronx, NY 10461 (United States); Miccio, Annarita [University of Modena e Reggio Emilia, Centro di Medicina Rigenerativa, Modena (Italy); Valle-Casuso, Jose Carlos; Perez, Patricio [Department of Microbiology and Immunology, Albert Einstein College of Medicine Bronx, NY 10461 (United States); Souque, Philippe [Molecular Virology and Vaccinology unit, CNRS URA 3015, Department of Virology, Institut Pasteur, 25-28 rue du Dr. Roux, 75015 Paris (France); Rizzi, Ermanno; Severgnini, Marco [Institute of Biomedical Technologies, CNR, Milano (Italy); Mavilio, Fulvio [University of Modena e Reggio Emilia, Centro di Medicina Rigenerativa, Modena (Italy); Genethon, Evry (France); Charneau, Pierre [Molecular Virology and Vaccinology unit, CNRS URA 3015, Department of Virology, Institut Pasteur, 25-28 rue du Dr. Roux, 75015 Paris (France); Diaz-Griffero, Felipe, E-mail: felipe.diaz-griffero@einstein.yu.edu [Department of Microbiology and Immunology, Albert Einstein College of Medicine Bronx, NY 10461 (United States)

    2013-05-25

    The early steps of HIV-1 replication involve the entry of HIV-1 into the nucleus, which is characterized by viral interactions with nuclear pore components. HIV-1 developed an evolutionary strategy to usurp the nuclear pore machinery and chromatin in order to integrate and efficiently express viral genes. In the current work, we studied the role of nucleoporins 153 and 98 (Nup153 and Nup98) in infection of human Jurkat lymphocytes by HIV-1. We showed that Nup153-depleted cells exhibited a defect in nuclear import, while depletion of Nup 98 caused a slight defect in HIV integration. To explore the biochemical viral determinants for the requirement of Nup153 and Nup98 during HIV-1 infection, we tested the ability of these nucleoporins to interact with HIV-1 cores. Our findings showed that both nucleoporins bind HIV-1 cores suggesting that this interaction is important for HIV-1 nuclear import and/or integration. Distribution analysis of integration sites in Nup153-depleted cells revealed a reduced tendency of HIV-1 to integrate in intragenic sites, which in part could account for the large infectivity defect observed in Nup153-depleted cells. Our work strongly supports a role for Nup153 in HIV-1 nuclear import and integration. - Highlights: ► We studied the role of Nup98 and Nup153 in HIV-1 infection. ► Nup98 binds the HIV-1 core and is involved in HIV-1 integration. ► Nup153 binds the HIV-1 core and is involved in HIV-1 nuclear import. ► Depletion of Nup153 decreased the integration of HIV-1 in transcriptionally active sites.

  19. Nup153 and Nup98 bind the HIV-1 core and contribute to the early steps of HIV-1 replication

    International Nuclear Information System (INIS)

    Di Nunzio, Francesca; Fricke, Thomas; Miccio, Annarita; Valle-Casuso, Jose Carlos; Perez, Patricio; Souque, Philippe; Rizzi, Ermanno; Severgnini, Marco; Mavilio, Fulvio; Charneau, Pierre; Diaz-Griffero, Felipe

    2013-01-01

    The early steps of HIV-1 replication involve the entry of HIV-1 into the nucleus, which is characterized by viral interactions with nuclear pore components. HIV-1 developed an evolutionary strategy to usurp the nuclear pore machinery and chromatin in order to integrate and efficiently express viral genes. In the current work, we studied the role of nucleoporins 153 and 98 (Nup153 and Nup98) in infection of human Jurkat lymphocytes by HIV-1. We showed that Nup153-depleted cells exhibited a defect in nuclear import, while depletion of Nup 98 caused a slight defect in HIV integration. To explore the biochemical viral determinants for the requirement of Nup153 and Nup98 during HIV-1 infection, we tested the ability of these nucleoporins to interact with HIV-1 cores. Our findings showed that both nucleoporins bind HIV-1 cores suggesting that this interaction is important for HIV-1 nuclear import and/or integration. Distribution analysis of integration sites in Nup153-depleted cells revealed a reduced tendency of HIV-1 to integrate in intragenic sites, which in part could account for the large infectivity defect observed in Nup153-depleted cells. Our work strongly supports a role for Nup153 in HIV-1 nuclear import and integration. - Highlights: ► We studied the role of Nup98 and Nup153 in HIV-1 infection. ► Nup98 binds the HIV-1 core and is involved in HIV-1 integration. ► Nup153 binds the HIV-1 core and is involved in HIV-1 nuclear import. ► Depletion of Nup153 decreased the integration of HIV-1 in transcriptionally active sites

  20. Anti-HIV-1 activity of flavonoid myricetin on HIV-1 infection in a dual-chamber in vitro model.

    Directory of Open Access Journals (Sweden)

    Silvana Pasetto

    Full Text Available HIV infection by sexual transmission remains an enormous global health concern. More than 1 million new infections among women occur annually. Microbicides represent a promising prevention strategy that women can easily control. Among emerging therapies, natural small molecules such as flavonoids are an important source of new active substances. In this study we report the in vitro cytotoxicity and anti-HIV-1 and microbicide activity of the following flavonoids: Myricetin, Quercetin and Pinocembrin. Cytotoxicity tests were conducted on TZM-bl, HeLa, PBMC, and H9 cell cultures using 0.01-100 µM concentrations. Myricetin presented the lowest toxic effect, with Quercetin and Pinocembrin relatively more toxic. The anti-HIV-1 activity was tested with TZM-bl cell plus HIV-1 BaL (R5 tropic, H9 and PBMC cells plus HIV-1 MN (X4 tropic, and the dual tropic (X4R5 HIV-1 89.6. All flavonoids showed anti-HIV activity, although Myricetin was more effective than Quercetin or Pinocembrin. In TZM-bl cells, Myricetin inhibited ≥90% of HIV-1 BaL infection. The results were confirmed by quantification of HIV-1 p24 antigen in supernatant from H9 and PBMC cells following flavonoid treatment. In H9 and PBMC cells infected by HIV-1 MN and HIV-1 89.6, Myricetin showed more than 80% anti-HIV activity. Quercetin and Pinocembrin presented modest anti-HIV activity in all experiments. Myricetin activity was tested against HIV-RT and inhibited the enzyme by 49%. Microbicide activities were evaluated using a dual-chamber female genital tract model. In the in vitro microbicide activity model, Myricetin showed promising results against different strains of HIV-1 while also showing insignificant cytotoxic effects. Further studies of Myricetin should be performed to identify its molecular targets in order to provide a solid biological foundation for translational research.

  1. IL-4 and IL-13 mediated down-regulation of CD8 expression levels can dampen anti-viral CD8⁺ T cell avidity following HIV-1 recombinant pox viral vaccination.

    Science.gov (United States)

    Wijesundara, Danushka K; Jackson, Ronald J; Tscharke, David C; Ranasinghe, Charani

    2013-09-23

    We have shown that mucosal HIV-1 recombinant pox viral vaccination can induce high, avidity HIV-specific CD8(+) T cells with reduced interleukin (IL)-4 and IL-13 expression compared to, systemic vaccine delivery. In the current study how these cytokines act to regulate anti-viral CD8(+) T, cell avidity following HIV-1 recombinant pox viral prime-boost vaccination was investigated. Out of a panel of T cell avidity markers tested, only CD8 expression levels were found to be enhanced on, KdGag197-205 (HIV)-specific CD8(+) T cells obtained from IL-13(-/-), IL-4(-/-) and signal transducer and, activator of transcription of 6 (STAT6)(-/-) mice compared to wild-type (WT) controls following, vaccination. Elevated CD8 expression levels in this instance also correlated with polyfunctionality, (interferon (IFN)-γ, tumour necorsis factor (TNF)-α and IL-2 production) and the avidity of HIVspecific CD8(+) T cells. Furthermore, mucosal vaccination and vaccination with the novel adjuvanted IL-13 inhibitor (i.e. IL-13Rα2) vaccines significantly enhanced CD8 expression levels on HIV-specific CD8(+), T cells, which correlated with avidity. Using anti-CD8 antibodies that blocked CD8 availability on CD8(+), T cells, it was established that CD8 played an important role in increasing HIV-specific CD8(+) T cell avidity and polyfunctionality in IL-4(-/-), IL-13(-/-) and STAT6(-/-) mice compared to WT controls, following vaccination. Collectively, our data demonstrate that IL-4 and IL-13 dampen CD8 expression levels on anti-viral CD8(+) T cells, which can down-regulate anti-viral CD8(+) T cell avidity and, polyfunctionality following HIV-1 recombinant pox viral vaccination. These findings can be exploited to, design more efficacious vaccines not only against HIV-1, but many chronic infections where high, avidity CD8(+) T cells help protection. Copyright © 2013 Elsevier Ltd. All rights reserved.

  2. Deciphering the role of the Gag-Pol ribosomal frameshift signal in HIV-1 RNA genome packaging.

    Science.gov (United States)

    Nikolaitchik, Olga A; Hu, Wei-Shau

    2014-04-01

    A key step of retroviral replication is packaging of the viral RNA genome during virus assembly. Specific packaging is mediated by interactions between the viral protein Gag and elements in the viral RNA genome. In HIV-1, similar to most retroviruses, the packaging signal is located within the 5' untranslated region and extends into the gag-coding region. A recent study reported that a region including the Gag-Pol ribosomal frameshift signal plays an important role in HIV-1 RNA packaging; deletions or mutations that affect the RNA structure of this signal lead to drastic decreases (10- to 50-fold) in viral RNA packaging and virus titer. We examined here the role of the ribosomal frameshift signal in HIV-1 RNA packaging by studying the RNA packaging and virus titer in the context of proviruses. Three mutants with altered ribosomal frameshift signal, either through direct deletion of the signal, mutation of the 6U slippery sequence, or alterations of the secondary structure were examined. We found that RNAs from all three mutants were packaged efficiently, and they generate titers similar to that of a virus containing the wild-type ribosomal frameshift signal. We conclude that although the ribosomal frameshift signal plays an important role in regulating the replication cycle, this RNA element is not directly involved in regulating RNA encapsidation. To generate infectious viruses, HIV-1 must package viral RNA genome during virus assembly. The specific HIV-1 genome packaging is mediated by interactions between the structural protein Gag and elements near the 5' end of the viral RNA known as packaging signal. In this study, we examined whether the Gag-Pol ribosomal frameshift signal is important for HIV-1 RNA packaging as recently reported. Our results demonstrated that when Gag/Gag-Pol is supplied in trans, none of the tested ribosomal frameshift signal mutants has defects in RNA packaging or virus titer. These studies provide important information on how HIV-1

  3. Cytoplasmic Dynein Promotes HIV-1 Uncoating

    Directory of Open Access Journals (Sweden)

    Paulina Pawlica

    2014-11-01

    Full Text Available Retroviral capsid (CA cores undergo uncoating during their retrograde transport (toward the nucleus, and/or after reaching the nuclear membrane. However, whether HIV-1 CA core uncoating is dependent upon its transport is not understood. There is some evidence that HIV-1 cores retrograde transport involves cytoplasmic dynein complexes translocating on microtubules. Here we investigate the role of dynein-dependent transport in HIV-1 uncoating. To interfere with dynein function, we depleted dynein heavy chain (DHC using RNA interference, and we over-expressed p50/dynamitin. In immunofluorescence microscopy experiments, DHC depletion caused an accumulation of CA foci in HIV-1 infected cells. Using a biochemical assay to monitor HIV-1 CA core disassembly in infected cells, we observed an increase in amounts of intact (pelletable CA cores upon DHC depletion or p50 over-expression. Results from these two complementary assays suggest that inhibiting dynein-mediated transport interferes with HIV-1 uncoating in infected cells, indicating the existence of a functional link between HIV-1 transport and uncoating.

  4. Genome-wide analysis of LTR-retrotransposon diversity and its impact on the evolution of the genus Helianthus (L.).

    Science.gov (United States)

    Mascagni, Flavia; Giordani, Tommaso; Ceccarelli, Marilena; Cavallini, Andrea; Natali, Lucia

    2017-08-18

    Genome divergence by mobile elements activity and recombination is a continuous process that plays a key role in the evolution of species. Nevertheless, knowledge on retrotransposon-related variability among species belonging to the same genus is still limited. Considering the importance of the genus Helianthus, a model system for studying the ecological genetics of speciation and adaptation, we performed a comparative analysis of the repetitive genome fraction across ten species and one subspecies of sunflower, focusing on long terminal repeat retrotransposons at superfamily, lineage and sublineage levels. After determining the relative genome size of each species, genomic DNA was isolated and subjected to Illumina sequencing. Then, different assembling and clustering approaches allowed exploring the repetitive component of all genomes. On average, repetitive DNA in Helianthus species represented more than 75% of the genome, being composed mostly by long terminal repeat retrotransposons. Also, the prevalence of Gypsy over Copia superfamily was observed and, among lineages, Chromovirus was by far the most represented. Although nearly all the same sublineages are present in all species, we found considerable variability in the abundance of diverse retrotransposon lineages and sublineages, especially between annual and perennial species. This large variability should indicate that different events of amplification or loss related to these elements occurred following species separation and should have been involved in species differentiation. Our data allowed us inferring on the extent of interspecific repetitive DNA variation related to LTR-RE abundance, investigating the relationship between changes of LTR-RE abundance and the evolution of the genus, and determining the degree of coevolution of different LTR-RE lineages or sublineages between and within species. Moreover, the data suggested that LTR-RE abundance in a species was affected by the annual or perennial

  5. Recognition of HIV-1 peptides by host CTL is related to HIV-1 similarity to human proteins.

    Directory of Open Access Journals (Sweden)

    Morgane Rolland

    Full Text Available BACKGROUND: While human immunodeficiency virus type 1 (HIV-1-specific cytotoxic T lymphocytes preferentially target specific regions of the viral proteome, HIV-1 features that contribute to immune recognition are not well understood. One hypothesis is that similarities between HIV and human proteins influence the host immune response, i.e., resemblance between viral and host peptides could preclude reactivity against certain HIV epitopes. METHODOLOGY/PRINCIPAL FINDINGS: We analyzed the extent of similarity between HIV-1 and the human proteome. Proteins from the HIV-1 B consensus sequence from 2001 were dissected into overlapping k-mers, which were then probed against a non-redundant database of the human proteome in order to identify segments of high similarity. We tested the relationship between HIV-1 similarity to host encoded peptides and immune recognition in HIV-infected individuals, and found that HIV immunogenicity could be partially modulated by the sequence similarity to the host proteome. ELISpot responses to peptides spanning the entire viral proteome evaluated in 314 individuals showed a trend indicating an inverse relationship between the similarity to the host proteome and the frequency of recognition. In addition, analysis of responses by a group of 30 HIV-infected individuals against 944 overlapping peptides representing a broad range of individual HIV-1B Nef variants, affirmed that the degree of similarity to the host was significantly lower for peptides with reactive epitopes than for those that were not recognized. CONCLUSIONS/SIGNIFICANCE: Our results suggest that antigenic motifs that are scarcely represented in human proteins might represent more immunogenic CTL targets not selected against in the host. This observation could provide guidance in the design of more effective HIV immunogens, as sequences devoid of host-like features might afford superior immune reactivity.

  6. No evidence of association between HIV-1 and malaria in populations with low HIV-1 prevalence.

    Directory of Open Access Journals (Sweden)

    Diego F Cuadros

    Full Text Available The geographic overlap between HIV-1 and malaria has generated much interest in their potential interactions. A variety of studies have evidenced a complex HIV-malaria interaction within individuals and populations that may have dramatic effects, but the causes and implications of this co-infection at the population level are still unclear. In a previous publication, we showed that the prevalence of malaria caused by the parasite Plasmodium falciparum is associated with HIV infection in eastern sub-Saharan Africa. To complement our knowledge of the HIV-malaria co-infection, the objective of this work was to assess the relationship between malaria and HIV prevalence in the western region of sub-Saharan Africa.Population-based cross-sectional data were obtained from the HIV/AIDS Demographic and Health Surveys conducted in Burkina Faso, Ghana, Guinea, Mali, Liberia and Cameroon, and the malaria atlas project. Using generalized linear mixed models, we assessed the relationship between HIV-1 and Plasmodium falciparum parasite rate (PfPR adjusting for important socio-economic and biological cofactors. We found no evidence that individuals living in areas with stable malaria transmission (PfPR>0.46 have higher odds of being HIV-positive than individuals who live in areas with PfPR≤0.46 in western sub-Saharan Africa (estimated odds ratio 1.14, 95% confidence interval 0.86-1.50. In contrast, the results suggested that PfPR was associated with being infected with HIV in Cameroon (estimated odds ratio 1.56, 95% confidence interval 1.23-2.00.Contrary to our previous research on eastern sub-Saharan Africa, this study did not identify an association between PfPR and infection with HIV in western sub-Saharan Africa, which suggests that malaria might not play an important role in the spread of HIV in populations where the HIV prevalence is low. Our work highlights the importance of understanding the epidemiologic effect of co-infection and the relevant

  7. Characteristics of HIV-1 serodiscordant couples enrolled in a clinical trial of antiretroviral pre-exposure prophylaxis for HIV-1 prevention.

    Directory of Open Access Journals (Sweden)

    Andrew Mujugira

    Full Text Available Stable heterosexual HIV-1 serodiscordant couples in Africa have high HIV-1 transmission rates and are a critical population for evaluation of new HIV-1 prevention strategies. The Partners PrEP Study is a randomized, double-blind, placebo-controlled trial of tenofovir and emtricitabine-tenofovir pre-exposure prophylaxis to decrease HIV-1 acquisition within heterosexual HIV-1 serodiscordant couples. We describe the trial design and characteristics of the study cohort.HIV-1 serodiscordant couples, in which the HIV-1 infected partner did not meet national guidelines for initiation of antiretroviral therapy, were enrolled at 9 research sites in Kenya and Uganda. The HIV-1 susceptible partner was randomized to daily oral tenofovir, emtricitabine-tenofovir, or matching placebo with monthly follow-up for 24-36 months.From July 2008 to November 2010, 7920 HIV-1 serodiscordant couples were screened and 4758 enrolled. For 62% (2966/4758 of enrolled couples, the HIV-1 susceptible partner was male. Median age was 33 years for HIV-1 susceptible and HIV-1 infected partners [IQR (28-40 and (26-39 respectively]. Most couples (98% were married, with a median duration of partnership of 7.0 years (IQR 3.0-14.0 and recent knowledge of their serodiscordant status [median 0.4 years (IQR 0.1-2.0]. During the month prior to enrollment, couples reported a median of 4 sex acts (IQR 2-8; 27% reported unprotected sex and 14% of male and 1% of female HIV-1 susceptible partners reported sex with outside partners. Among HIV-1 infected partners, the median plasma HIV-1 level was 3.94 log(10 copies/mL (IQR 3.31-4.53 and median CD4 count was 496 cells/µL (IQR 375-662; the majority (64% had WHO stage 1 HIV-1 disease.Couples at high risk of HIV-1 transmission were rapidly recruited into the Partners PrEP Study, the largest efficacy trial of oral PrEP. (ClinicalTrials.gov NCT00557245.

  8. Calcitonin Gene-Related Peptide Induces HIV-1 Proteasomal Degradation in Mucosal Langerhans Cells.

    Science.gov (United States)

    Bomsel, Morgane; Ganor, Yonatan

    2017-12-01

    to CD4 + T cells, the principal HIV-1 targets. We previously found that the neuroimmune dialogue between LCs and peripheral neurons, innervating mucosal epithelia, significantly inhibits trans -infection via the action of the secreted neuropeptide CGRP on LCs. In this study, we investigated whether CGRP-induced inhibition of trans -infection is linked to CGRP-controlled HIV-1 degradation in LCs. We show that in untreated LCs, HIV-1 is functionally degraded in endolysosomes. In sharp contrast, we reveal that in CGRP-treated LCs, HIV-1 is diverted toward and degraded via another cytosolic protein degradative pathway, namely, the proteasome. These results establish that CGRP regulates HIV-1 degradation in LCs. As CGRP contributes to the sexual response and present within mucosal epithelia, HIV-1 proteasomal degradation in LCs might predominate in vivo and should be enhanced clinically. Copyright © 2017 American Society for Microbiology.

  9. Human CNS cultures exposed to HIV-1 gp120 reproduce dendritic injuries of HIV-1-associated dementia

    Directory of Open Access Journals (Sweden)

    Hammond Robert R

    2004-05-01

    Full Text Available Abstract HIV-1-associated dementia remains a common subacute to chronic central nervous system degeneration in adult and pediatric HIV-1 infected populations. A number of viral and host factors have been implicated including the HIV-1 120 kDa envelope glycoprotein (gp120. In human post-mortem studies using confocal scanning laser microscopy for microtubule-associated protein 2 and synaptophysin, neuronal dendritic pathology correlated with dementia. In the present study, primary human CNS cultures exposed to HIV-1 gp120 at 4 weeks in vitro suffered gliosis and dendritic damage analogous to that described in association with HIV-1-associated dementia.

  10. Human endogenous retrovirus K Gag coassembles with HIV-1 Gag and reduces the release efficiency and infectivity of HIV-1.

    Science.gov (United States)

    Monde, Kazuaki; Contreras-Galindo, Rafael; Kaplan, Mark H; Markovitz, David M; Ono, Akira

    2012-10-01

    Human endogenous retroviruses (HERVs), which are remnants of ancestral retroviruses integrated into the human genome, are defective in viral replication. Because activation of HERV-K and coexpression of this virus with HIV-1 have been observed during HIV-1 infection, it is conceivable that HERV-K could affect HIV-1 replication, either by competition or by cooperation, in cells expressing both viruses. In this study, we found that the release efficiency of HIV-1 Gag was 3-fold reduced upon overexpression of HERV-K(CON) Gag. In addition, we observed that in cells expressing Gag proteins of both viruses, HERV-K(CON) Gag colocalized with HIV-1 Gag at the plasma membrane. Furthermore, HERV-K(CON) Gag was found to coassemble with HIV-1 Gag, as demonstrated by (i) processing of HERV-K(CON) Gag by HIV-1 protease in virions, (ii) coimmunoprecipitation of virion-associated HERV-K(CON) Gag with HIV-1 Gag, and (iii) rescue of a late-domain-defective HERV-K(CON) Gag by wild-type (WT) HIV-1 Gag. Myristylation-deficient HERV-K(CON) Gag localized to nuclei, suggesting cryptic nuclear trafficking of HERV-K Gag. Notably, unlike WT HERV-K(CON) Gag, HIV-1 Gag failed to rescue myristylation-deficient HERV-K(CON) Gag to the plasma membrane. Efficient colocalization and coassembly of HIV-1 Gag and HERV-K Gag also required nucleocapsid (NC). These results provide evidence that HIV-1 Gag heteromultimerizes with HERV-K Gag at the plasma membrane, presumably through NC-RNA interaction. Intriguingly, HERV-K Gag overexpression reduced not only HIV-1 release efficiency but also HIV-1 infectivity in a myristylation- and NC-dependent manner. Altogether, these results indicate that Gag proteins of endogenous retroviruses can coassemble with HIV-1 Gag and modulate the late phase of HIV-1 replication.

  11. The anti-HIV-1 effect of scutellarin

    International Nuclear Information System (INIS)

    Zhang Gaohong; Wang Qian; Chen Jijun; Zhang Xuemei; Tam, S.-C.; Zheng Yongtang

    2005-01-01

    Scutellarin was purified from the plant Erigeron breviscapus (Vant.) Hand.-Mazz. The activity against 3 strains of human immunodeficiency virus (HIV) was determined in vitro in this study. These were laboratory-derived virus (HIV-1 IIIB ), drug-resistant virus (HIV-1 74V ), and low-passage clinical isolated virus (HIV-1 KM018 ). From syncytia inhibition study, the EC 50 of scutellarin against HIV-1 IIIB direct infection in C8166 cells was 26 μM with a therapeutic index of 36. When the mode of infection changed from acute infection to cell-to-cell infection, this compound became even more potent and the EC 50 reduced to 15 μM. This suggested that cell fusion might be affected by this compound. By comparing the inhibitory effects on p24 antigen, scutellarin was also found to be active against HIV-1 74V (EC 50 253 μM) and HIV-1 KM018 (EC 50 136 μM) infection with significant difference in potency. The mechanism of its action was also explored in this study. At a concentration of 433 μM, scutellarin inhibited 48% of the cell free recombinant HIV-1 RT activity. It also caused 82% inhibition of HIV-1 particle attachment and 45% inhibition of fusion at the concentrations of 54 μM. In summary, scutellarin was found to inhibit several strains of HIV-1 replication with different potencies. It appeared to inhibit HIV-1 RT activity, HIV-1 particle attachment and cell fusion. These are essential activities for viral transmission and replication

  12. MicroRNA-210, MicroRNA-331, and MicroRNA-7 Are Differentially Regulated in Treated HIV-1–Infected Individuals and Are Associated With Markers of Systemic Inflammation

    DEFF Research Database (Denmark)

    Ballegaard, Vibe; Ralfkiaer, Ulrik; Pedersen, Karin K.

    2017-01-01

    in inflammation and CVD risk and to investigate associations between these and systemic inflammation. Methods: In a screening cohort including 14 HIV-1-infected individuals and 9 uninfected controls, microarray profiling was performed using peripheral blood mononuclear cells (PBMCs). Differentially regulated mi......-sensitivity C-reactive protein, lipopolysaccharide (LPS), cytomegalovirus immunoglobulin G, lipids, and fasting glucose were measured, and associations with validated miRNAs were assessed with multiple linear regression analysis. Results: Upregulation of miR-210, miR-7, and miR-331 was found in PBMCs from HIV-1...... with tumor necrosis factor-alpha (P = 0.004). MiR-7 in PBMC was positively associated with interleukin-6 (P = 0.025) and fasting glucose (P = 0.005), whereas miR-331 was negatively associated with LPS (P = 0.006). In PBMCs from HIV-1-infected individuals with low cytomegalovirus immunoglobulin G, miR-7, mi...

  13. The Oncolytic Virus MG1 Targets and Eliminates Cells Latently Infected With HIV-1: Implications for an HIV Cure.

    Science.gov (United States)

    Ranganath, Nischal; Sandstrom, Teslin S; Burke Schinkel, Stephanie C; Côté, Sandra C; Angel, Jonathan B

    2018-02-14

    Cells latently infected with human immunodeficiency virus (HIV) evade immune- and drug-mediated clearance. These cells harbor intracellular signaling defects, including impairment of the antiviral type I interferon response. Such defects have also been observed in several cancers and have been exploited for the development of therapeutic oncolytic viruses, including the recombinant Maraba virus (MG1). We therefore hypothesized that MG1 would infect and eliminate cells latently infected with HIV-1, while sparing healthy uninfected cells. Preferential infection and elimination by MG1 was first demonstrated in cell lines latently infected with HIV-1. Following this, a reduction in HIV-1 DNA and inducible HIV-1 replication was observed following MG1 infection of latently infected, resting CD4+ T cells generated using an in vitro model of latency. Last, MG1 infection resulted in a reduction in HIV-1 DNA and inducible HIV-1 replication in memory CD4+ T cells isolated from effectively treated, HIV-1-infected individuals. Our results therefore highlight a novel approach to eliminate the latent HIV-1 reservoir. © The Author(s) 2017. Published by Oxford University Press for the Infectious Diseases Society of America.

  14. Interferon-inducible protein 10 (IP-10) is associated with viremia of early HIV-1 infection in Korean patients.

    Science.gov (United States)

    Lee, SoYong; Chung, Yoon-Seok; Yoon, Cheol-Hee; Shin, YoungHyun; Kim, SeungHyun; Choi, Byeong-Sun; Kim, Sung Soon

    2015-05-01

    Cytokines/chemokines play key roles in modulating disease progression in human immunodeficiency virus (HIV) infection. Although it is known that early HIV-1 infection is associated with increased production of proinflammatory cytokines, the relationship between cytokine levels and HIV-1 pathogenesis is not clear. The concentrations of 18 cytokines/chemokines in 30 HIV-1 negative and 208 HIV-1 positive plasma samples from Korean patients were measured by the Luminex system. Early HIV-1 infection was classified according to the Fiebig stage (FS) based on the characteristics of the patients infected with HIV-1. Concentrations of interleukin-12 (IL-12), interferon-inducible protein-10 (IP-10), macrophage inflammatory protein-1α (MIP-1α) and regulated upon activation, normal T cells expressed and secreted (RANTES) were increased significantly during the early stage of HIV-1 infection (FS II-IV) compared with the HIV-1-negative group. Of these cytokines, an elevated level of IP-10 was the only factor to be correlated positively with a higher viral load during the early stages of HIV-1 infection (FS II-IV) in Koreans (R = 0.52, P IP-10 may be an indicator for HIV-1 viremia and associated closely with viral replication in patients with early HIV-1 infection. © 2015 Wiley Periodicals, Inc.

  15. Viral linkage in HIV-1 seroconverters and their partners in an HIV-1 prevention clinical trial.

    Directory of Open Access Journals (Sweden)

    Mary S Campbell

    2011-03-01

    Full Text Available Characterization of viruses in HIV-1 transmission pairs will help identify biological determinants of infectiousness and evaluate candidate interventions to reduce transmission. Although HIV-1 sequencing is frequently used to substantiate linkage between newly HIV-1 infected individuals and their sexual partners in epidemiologic and forensic studies, viral sequencing is seldom applied in HIV-1 prevention trials. The Partners in Prevention HSV/HIV Transmission Study (ClinicalTrials.gov #NCT00194519 was a prospective randomized placebo-controlled trial that enrolled serodiscordant heterosexual couples to determine the efficacy of genital herpes suppression in reducing HIV-1 transmission; as part of the study analysis, HIV-1 sequences were examined for genetic linkage between seroconverters and their enrolled partners.We obtained partial consensus HIV-1 env and gag sequences from blood plasma for 151 transmission pairs and performed deep sequencing of env in some cases. We analyzed sequences with phylogenetic techniques and developed a Bayesian algorithm to evaluate the probability of linkage. For linkage, we required monophyletic clustering between enrolled partners' sequences and a Bayesian posterior probability of ≥ 50%. Adjudicators classified each seroconversion, finding 108 (71.5% linked, 40 (26.5% unlinked, and 3 (2.0% indeterminate transmissions, with linkage determined by consensus env sequencing in 91 (84%. Male seroconverters had a higher frequency of unlinked transmissions than female seroconverters. The likelihood of transmission from the enrolled partner was related to time on study, with increasing numbers of unlinked transmissions occurring after longer observation periods. Finally, baseline viral load was found to be significantly higher among linked transmitters.In this first use of HIV-1 sequencing to establish endpoints in a large clinical trial, more than one-fourth of transmissions were unlinked to the enrolled partner

  16. The HIV-1 leader RNA conformational switch regulates RNA dimerization but does not regulate mRNA translation

    NARCIS (Netherlands)

    Abbink, Truus E. M.; Ooms, Marcel; Haasnoot, P. C. Joost; Berkhout, Ben

    2005-01-01

    The untranslated leader RNA is the most conserved part of the human immunodeficiency virus type I (HIV-1) genome. It contains many regulatory motifs that mediate a variety of steps in the viral life cycle. Previous work showed that the full-length leader RNA can adopt two alternative structures: a

  17. Safety and immunogenicity of HIV-1 Tat toxoid in immunocompromised HIV-1-infected patients.

    Science.gov (United States)

    Gringeri, A; Santagostino, E; Muça-Perja, M; Mannucci, P M; Zagury, J F; Bizzini, B; Lachgar, A; Carcagno, M; Rappaport, J; Criscuolo, M; Blattner, W; Burny, A; Gallo, R C; Zagury, D

    1998-01-01

    To antagonize the deleterious effects of the HIV-1 toxin extracellular Tat on uninfected immune cells, we developed a new strategy of anti-HIV-1 vaccine using an inactivated but immunogenic Tat (Tat toxoid). Tat toxoid has been assayed for safety and immunogenicity in seropositive patients. The phase I vaccine clinical trial testing Tat toxoid preparation in Seppic Isa 51 oil adjuvant was performed on 14 HIV-1-infected asymptomatic although biologically immunocompromised individuals (500-200 CD4+ cells/mm3). Following as many as 8 injections, no clinical defects were observed. All patients exhibited an antibody (Ab) response to Tat, and some had cell-mediated immunity (CMI) as evaluated by skin test in vivo and T-cell proliferation in vitro. These results provide initial evidence of safety and potency of Tat toxoid vaccination in HIV-1-infected individuals.

  18. Proteomic Profiling of a Primary CD4+ T Cell Model of HIV-1 Latency Identifies Proteins Whose Differential Expression Correlates with Reactivation of Latent HIV-1.

    Science.gov (United States)

    Saha, Jamaluddin Md; Liu, Hongbing; Hu, Pei-Wen; Nikolai, Bryan C; Wu, Hulin; Miao, Hongyu; Rice, Andrew P

    2018-01-01

    The latent HIV-1 reservoir of memory CD4 + T cells that persists during combination antiviral therapy prevents a cure of infection. Insight into mechanisms of latency and viral reactivation are essential for the rational design of strategies to reduce the latent reservoir. In this study, we quantified the levels of >2,600 proteins in the CCL19 primary CD4 + T cell model of HIV-1 latency. We profiled proteins under conditions that promote latent infection and after cells were treated with phorbol 12-myristate 13-acetate (PMA) + ionomycin, which is known to efficiently induce reactivation of latent HIV-1. In an analysis of cells from two healthy blood donors, we identified 61 proteins that were upregulated ≥2-fold, and 36 proteins that were downregulated ≥2-fold under conditions in which latent viruses were reactivated. These differentially expressed proteins are, therefore, candidates for cellular factors that regulate latency or viral reactivation. Two unexpected findings were obtained from the proteomic data: (1) the interactions among the majority of upregulated proteins are largely undetermined in published protein-protein interaction networks and (2) downregulated proteins are strongly associated with Gene Ontology terms related to mitochondrial protein synthesis. This proteomic data set provides a useful resource for future mechanistic studies of HIV-1 latency.

  19. HIV-1 induces DCIR expression in CD4+ T cells.

    Directory of Open Access Journals (Sweden)

    Alexandra A Lambert

    2010-11-01

    Full Text Available The C-type lectin receptor DCIR, which has been shown very recently to act as an attachment factor for HIV-1 in dendritic cells, is expressed predominantly on antigen-presenting cells. However, this concept was recently challenged by the discovery that DCIR can also be detected in CD4(+ T cells found in the synovial tissue from rheumatoid arthritis (RA patients. Given that RA and HIV-1 infections share common features such as a chronic inflammatory condition and polyclonal immune hyperactivation status, we hypothesized that HIV-1 could promote DCIR expression in CD4(+ T cells. We report here that HIV-1 drives DCIR expression in human primary CD4(+ T cells isolated from patients (from both aviremic/treated and viremic/treatment naive persons and cells acutely infected in vitro (seen in both virus-infected and uninfected cells. Soluble factors produced by virus-infected cells are responsible for the noticed DCIR up-regulation on uninfected cells. Infection studies with Vpr- or Nef-deleted viruses revealed that these two viral genes are not contributing to the mechanism of DCIR induction that is seen following acute infection of CD4(+ T cells with HIV-1. Moreover, we report that DCIR is linked to caspase-dependent (induced by a mitochondria-mediated generation of free radicals and -independent intrinsic apoptotic pathways (involving the death effector AIF. Finally, we demonstrate that the higher surface expression of DCIR in CD4(+ T cells is accompanied by an enhancement of virus attachment/entry, replication and transfer. This study shows for the first time that HIV-1 induces DCIR membrane expression in CD4(+ T cells, a process that might promote virus dissemination throughout the infected organism.

  20. Gene expression profiling of the host response to HIV-1 B, C, or A/E infection in monocyte-derived dendritic cells

    International Nuclear Information System (INIS)

    Solis, Mayra; Wilkinson, Peter; Romieu, Raphaelle; Hernandez, Eduardo; Wainberg, Mark A.; Hiscott, John

    2006-01-01

    Dendritic cells (DC) are among the first targets of human immunodeficiency virus type-1 (HIV-1) infection and in turn play a crucial role in viral transmission to T cells and in the regulation of the immune response. The major group of HIV-1 has diversified genetically based on variation in env sequences and comprise at least 11 subtypes. Because little is known about the host response elicited against different HIV-1 clade isolates in vivo, we sought to use gene expression profiling to identify genes regulated by HIV-1 subtypes B, C, and A/E upon de novo infection of primary immature monocyte-derived DC (iMDDCs). A total of 3700 immune-related genes were subjected to a significance analysis of microarrays (SAM); 656 genes were selected as significant and were further divided into 8 functional categories. Regardless of the time of infection, 20% of the genes affected by HIV-1 were involved in signal transduction, followed by 14% of the genes identified as transcription-related genes, and 7% were classified as playing a role in cell proliferation and cell cycle. Furthermore, 7% of the genes were immune response genes. By 72 h postinfection, genes upregulated by subtype B included the inhibitor of the matrix metalloproteinase TIMP2 and the heat shock protein 40 homolog (Hsp40) DNAJB1, whereas the IFN inducible gene STAT1, the MAPK1/ERK2 kinase regulator ST5, and the chemokine CXCL3 and SHC1 genes were induced by subtypes C and A/E. These analyses distinguish a temporally regulated host response to de novo HIV-1 infection in primary dendritic cells

  1. Nuclear exportin receptor CAS regulates the NPI-1-mediated nuclear import of HIV-1 Vpr.

    Directory of Open Access Journals (Sweden)

    Eri Takeda

    Full Text Available Vpr, an accessory protein of human immunodeficiency virus type 1, is a multifunctional protein that plays an important role in viral replication. We have previously shown that the region between residues 17 and 74 of Vpr (Vpr(N17C74 contained a bona fide nuclear localization signal and it is targeted Vpr(N17C74 to the nuclear envelope and then imported into the nucleus by importin α (Impα alone. The interaction between Impα and Vpr is important not only for the nuclear import of Vpr but also for HIV-1 replication in macrophages; however, it was unclear whether full-length Vpr enters the nucleus in a manner similar to Vpr(N17C74. This study investigated the nuclear import of full-length Vpr using the three typical Impα isoforms, Rch1, Qip1 and NPI-1, and revealed that full-length Vpr is selectively imported by NPI-1, but not Rch1 and Qip1, after it makes contact with the perinuclear region in digitonin-permeabilized cells. A binding assay using the three Impα isoforms showed that Vpr bound preferentially to the ninth armadillo repeat (ARM region (which is also essential for the binding of CAS, the export receptor for Impα in all three isoforms. Comparison of biochemical binding affinities between Vpr and the Impα isoforms using surface plasmon resonance analysis demonstrated almost identical values for the binding of Vpr to the full-length isoforms and to their C-terminal domains. By contrast, the data showed that, in the presence of CAS, Vpr was released from the Vpr/NPI-1 complex but was not released from Rch1 or Qip1. Finally, the NPI-1-mediated nuclear import of Vpr was greatly reduced in semi-intact CAS knocked-down cells and was recovered by the addition of exogenous CAS. This report is the first to show the requirement for and the regulation of CAS in the functioning of the Vpr-Impα complex.

  2. Transcriptional regulation of HIV-1 host factor COMMD1 by the Sp family.

    Science.gov (United States)

    Kudo, Eriko; Taura, Manabu; Suico, Mary Ann; Goto, Hiroki; Kai, Hirofumi; Okada, Seiji

    2018-04-01

    Copper metabolism Murr1 domain containing 1 (COMMD1) has multiple functions in the regulation of protein stability at the plasma membrane and in the cytoplasm. However, the regulation of COMMD1 transcriptional has remained to be elucidated. In the present study, the 5'‑flanking region (‑1,192/+83 bp) of the human COMMD1 gene was cloned. It was observed that the COMMD1 promoter region contains GC‑rich region that has 7 putative Sp1‑binding sites via in silico analysis. The proximal promoter region at ‑289/+83 bp was required for COMMD1 basal promoter activity by deletion constructs of COMMD1 promoter. Moreover, Sp1 inhibitor, mithramycin A, suppressed basal COMMD1 promoter activity. The Sp1‑binding site (‑11/‑1 bp) in the proximal promoter region was a critical site for COMMD1 gene regulation by Sp1 and Sp3. Sp1 upregulated COMMD1 promoter activity, whereas Sp3 suppressed it. Endogenous Sp1 and Sp3 bound to the proximal promoter region of COMMD1. Taken together, Sp1 constitutively regulates the basal expression of the COMMD1 gene in human epithelial cell lines.

  3. Enhanced glucagon-like peptide-1 (GLP-1) response to oral glucose in glucose-intolerant HIV-infected patients on antiretroviral therapy

    DEFF Research Database (Denmark)

    Andersen, O; Haugaard, S B; Holst, Jens Juul

    2005-01-01

    concentrations of GLP-1 and GIP were determined frequently during a 3-h, 75-g glucose tolerance test. Insulin secretion rates (ISRs) were calculated by deconvolution of C-peptide concentrations. RESULTS: The incremental area under the curve (incrAUC) for GLP-1 was increased by 250% in IGT patients compared...... without adjustment (r=0.38, Pglucose incrAUC (r=0.49, Pglucose-intolerant, HIV-infected male patients may display enhanced GLP-1 responses to oral glucose compared with normal glucose-tolerant HIV-infected male patients......OBJECTIVES: We investigated whether the incretin hormones glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP), which are major regulators of glucose tolerance through the stimulation of insulin secretion, contribute to impaired glucose tolerance (IGT) among HIV...

  4. Nullbasic, a potent anti-HIV tat mutant, induces CRM1-dependent disruption of HIV rev trafficking.

    Directory of Open Access Journals (Sweden)

    Min-Hsuan Lin

    Full Text Available Nullbasic, a mutant of the HIV-1 Tat protein, has anti-HIV-1 activity through mechanisms that include inhibition of Rev function and redistribution of the HIV-1 Rev protein from the nucleolus to the nucleoplasm and cytoplasm. Here we investigate the mechanism of this effect for the first time, establishing that redistribution of Rev by Nullbasic is not due to direct interaction between the two proteins. Rather, Nullbasic affects subcellular localization of cellular proteins that regulate Rev trafficking. In particular, Nullbasic induced redistribution of exportin 1 (CRM1, nucleophosmin (B23 and nucleolin (C23 from the nucleolus to the nucleus when Rev was coexpressed, but never in its absence. Inhibition of the Rev:CRM1 interaction by leptomycin B or a non-interacting RevM10 mutant completely blocked redistribution of Rev by Nullbasic. Finally, Nullbasic did not inhibit importin β- or transportin 1-mediated nuclear import, suggesting that cytoplasmic accumulation of Rev was due to increased export by CRM1. Overall, our data support the conclusion that CRM1-dependent subcellular redistribution of Rev from the nucleolus by Nullbasic is not through general perturbation of either nuclear import or export. Rather, Nullbasic appears to interact with and disrupt specific components of a Rev trafficking complex required for its nucleocytoplasmic shuttling and, in particular, its nucleolar accumulation.

  5. I-mfa domain proteins specifically interact with HTLV-1 Tax and repress its transactivating functions

    International Nuclear Information System (INIS)

    Kusano, Shuichi; Yoshimitsu, Makoto; Hachiman, Miho; Ikeda, Masanori

    2015-01-01

    The I-mfa domain proteins HIC (also known as MDFIC) and I-mfa (also known as MDFI) are candidate tumor suppressor genes that are involved in cellular and viral transcriptional regulation. Here, we show that HIC and I-mfa directly interact with human T-cell leukemia virus type-1 (HTLV-1) Tax protein in vitro. In addition, HIC and I-mfa repress Tax-dependent transactivation of an HTLV-1 long terminal repeat (LTR) reporter construct in COS-1, Jurkat and high-Tax-producing HTLV-1-infected T cells. HIC also interacts with Tax through its I-mfa domain in vivo and represses Tax-dependent transactivation of HTLV-1 LTR and NF-κB reporter constructs in an interaction-dependent manner. Furthermore, we show that HIC decreases the nuclear distribution and stimulates the proteasomal degradation of Tax. These data reveal that HIC specifically interacts with HTLV-1 Tax and negatively regulates Tax transactivational activity by altering its subcellular distribution and stability. - Highlights: • I-mfa domain proteins, HIC and I-mfa, specifically interact with HTLV-1 Tax. • HIC and I-mfa repress the Tax-dependent transactivation of HTLV-1 LTR. • HIC represses the Tax-dependent transactivation of NF-κΒ. • HIC decreases the nuclear distribution of Tax. • HIC stimulates the proteasomal degradation of Tax.

  6. I-mfa domain proteins specifically interact with HTLV-1 Tax and repress its transactivating functions

    Energy Technology Data Exchange (ETDEWEB)

    Kusano, Shuichi, E-mail: skusano@m2.kufm.kagoshima-u.ac.jp [Division of Persistent and Oncogenic Viruses, Center for Chronic Viral Diseases, Graduate School of Medical and Dental Sciences, Kagoshima University, 8-35-1 Sakuragaoka, Kagoshima 890-8544 (Japan); Yoshimitsu, Makoto; Hachiman, Miho [Division of Hematology and Immunology, Center for Chronic Viral Diseases, Graduate School of Medical and Dental Sciences, Kagoshima University, 8-35-1 Sakuragaoka, Kagoshima 890-8544 (Japan); Ikeda, Masanori [Division of Persistent and Oncogenic Viruses, Center for Chronic Viral Diseases, Graduate School of Medical and Dental Sciences, Kagoshima University, 8-35-1 Sakuragaoka, Kagoshima 890-8544 (Japan)

    2015-12-15

    The I-mfa domain proteins HIC (also known as MDFIC) and I-mfa (also known as MDFI) are candidate tumor suppressor genes that are involved in cellular and viral transcriptional regulation. Here, we show that HIC and I-mfa directly interact with human T-cell leukemia virus type-1 (HTLV-1) Tax protein in vitro. In addition, HIC and I-mfa repress Tax-dependent transactivation of an HTLV-1 long terminal repeat (LTR) reporter construct in COS-1, Jurkat and high-Tax-producing HTLV-1-infected T cells. HIC also interacts with Tax through its I-mfa domain in vivo and represses Tax-dependent transactivation of HTLV-1 LTR and NF-κB reporter constructs in an interaction-dependent manner. Furthermore, we show that HIC decreases the nuclear distribution and stimulates the proteasomal degradation of Tax. These data reveal that HIC specifically interacts with HTLV-1 Tax and negatively regulates Tax transactivational activity by altering its subcellular distribution and stability. - Highlights: • I-mfa domain proteins, HIC and I-mfa, specifically interact with HTLV-1 Tax. • HIC and I-mfa repress the Tax-dependent transactivation of HTLV-1 LTR. • HIC represses the Tax-dependent transactivation of NF-κΒ. • HIC decreases the nuclear distribution of Tax. • HIC stimulates the proteasomal degradation of Tax.

  7. Inhibition of human immunodeficiency virus type 1 (HIV-1) nuclear import via Vpr-Importin α interactions as a novel HIV-1 therapy

    International Nuclear Information System (INIS)

    Suzuki, Tatsunori; Yamamoto, Norio; Nonaka, Mizuho; Hashimoto, Yoshie; Matsuda, Go; Takeshima, Shin-nosuke; Matsuyama, Megumi; Igarashi, Tatsuhiko; Miura, Tomoyuki; Tanaka, Rie; Kato, Shingo; Aida, Yoko

    2009-01-01

    The development of multidrug-resistant viruses compromises the efficacy of anti-human immunodeficiency virus (HIV) therapy and limits treatment options. Therefore, new targets that can be used to develop novel antiviral agents need to be identified. One such target is the interaction between Vpr, one of the accessory gene products of HIV-1 and Importin α, which is crucial, not only for the nuclear import of Vpr, but also for HIV-1 replication in macrophages. We have identified a potential parent compound, hematoxylin, which suppresses Vpr-Importin α interaction, thereby inhibiting HIV-1 replication in a Vpr-dependent manner. Analysis by real-time PCR demonstrated that hematoxylin specifically inhibited nuclear import step of pre-integration complex. Thus, hematoxylin is a new anti-HIV-1 inhibitor that targets the nuclear import of HIV-1 via the Vpr-Importin α interaction, suggesting that a specific inhibitor of the interaction between viral protein and the cellular factor may provide a new strategy for HIV-1 therapy.

  8. HIV-1 RNAs are Not Part of the Argonaute 2 Associated RNA Interference Pathway in Macrophages.

    Directory of Open Access Journals (Sweden)

    Valentina Vongrad

    Full Text Available MiRNAs and other small noncoding RNAs (sncRNAs are key players in post-transcriptional gene regulation. HIV-1 derived small noncoding RNAs (sncRNAs have been described in HIV-1 infected cells, but their biological functions still remain to be elucidated. Here, we approached the question whether viral sncRNAs may play a role in the RNA interference (RNAi pathway or whether viral mRNAs are targeted by cellular miRNAs in human monocyte derived macrophages (MDM.The incorporation of viral sncRNAs and/or their target RNAs into RNA-induced silencing complex was investigated using photoactivatable ribonucleoside-induced cross-linking and immunoprecipitation (PAR-CLIP as well as high-throughput sequencing of RNA isolated by cross-linking immunoprecipitation (HITS-CLIP, which capture Argonaute2-bound miRNAs and their target RNAs. HIV-1 infected monocyte-derived macrophages (MDM were chosen as target cells, as they have previously been shown to express HIV-1 sncRNAs. In addition, we applied small RNA deep sequencing to study differential cellular miRNA expression in HIV-1 infected versus non-infected MDMs.PAR-CLIP and HITS-CLIP data demonstrated the absence of HIV-1 RNAs in Ago2-RISC, although the presence of a multitude of HIV-1 sncRNAs in HIV-1 infected MDMs was confirmed by small RNA sequencing. Small RNA sequencing revealed that 1.4% of all sncRNAs were of HIV-1 origin. However, neither HIV-1 derived sncRNAs nor putative HIV-1 target sequences incorporated into Ago2-RISC were identified suggesting that HIV-1 sncRNAs are not involved in the canonical RNAi pathway nor is HIV-1 targeted by this pathway in HIV-1 infected macrophages.

  9. Artificial 64-Residue HIV-1 Enhancer-Binding Peptide Is a Potent Inhibitor of Viral Replication in HIV-1-Infected Cells.

    Science.gov (United States)

    Oufir, Mouhssin; Bisset, Leslie R; Hoffmann, Stefan R K; Xue, Gongda; Klauser, Stephan; Bergamaschi, Bianca; Gervaix, Alain; Böni, Jürg; Schüpbach, Jörg; Gutte, Bernd

    2011-01-01

    An artificial HIV-1 enhancer-binding peptide was extended by nine consecutive arginine residues at the C-terminus and by the nuclear localization signal of SV40 large T antigen at the N-terminus. The resulting synthetic 64-residue peptide was found to bind to the two enhancers of the HIV-1 long terminal repeat, cross the plasma membrane and the nuclear envelope of human cells, and suppress the HIV-1 enhancer-controlled expression of a green fluorescent protein reporter gene. Moreover, HIV-1 replication is inhibited by this peptide in HIV-1-infected CEM-GFP cells as revealed by HIV-1 p24 ELISA and real-time RT-PCR of HIV-1 RNA. Rapid uptake of this intracellular stable and inhibitory peptide into the cells implies that this peptide may have the potential to attenuate HIV-1 replication in vivo.

  10. Transcriptional Reprogramming during Effector-to-Memory Transition Renders CD4+ T Cells Permissive for Latent HIV-1 Infection.

    Science.gov (United States)

    Shan, Liang; Deng, Kai; Gao, Hongbo; Xing, Sifei; Capoferri, Adam A; Durand, Christine M; Rabi, S Alireza; Laird, Gregory M; Kim, Michelle; Hosmane, Nina N; Yang, Hung-Chih; Zhang, Hao; Margolick, Joseph B; Li, Linghua; Cai, Weiping; Ke, Ruian; Flavell, Richard A; Siliciano, Janet D; Siliciano, Robert F

    2017-10-17

    The latent reservoir for HIV-1 in resting memory CD4 + T cells is the major barrier to curing HIV-1 infection. Studies of HIV-1 latency have focused on regulation of viral gene expression in cells in which latent infection is established. However, it remains unclear how infection initially becomes latent. Here we described a unique set of properties of CD4 + T cells undergoing effector-to-memory transition including temporary upregulation of CCR5 expression and rapid downregulation of cellular gene transcription. These cells allowed completion of steps in the HIV-1 life cycle through integration but suppressed HIV-1 gene transcription, thus allowing the establishment of latency. CD4 + T cells in this stage were substantially more permissive for HIV-1 latent infection than other CD4 + T cells. Establishment of latent HIV-1 infection in CD4 + T could be inhibited by viral-specific CD8 + T cells, a result with implications for elimination of latent HIV-1 infection by T cell-based vaccines. Copyright © 2017. Published by Elsevier Inc.

  11. HIV-1 envelope glycoprotein

    Science.gov (United States)

    Caulfield, Michael; Cupo, Albert; Dean, Hansi; Hoffenberg, Simon; King, C. Richter; Klasse, P. J.; Marozsan, Andre; Moore, John P.; Sanders, Rogier W.; Ward, Andrew; Wilson, Ian; Julien, Jean-Philippe

    2017-08-22

    The present application relates to novel HIV-1 envelope glycoproteins, which may be utilized as HIV-1 vaccine immunogens, and antigens for crystallization, electron microscopy and other biophysical, biochemical and immunological studies for the identification of broad neutralizing antibodies. The present invention encompasses the preparation and purification of immunogenic compositions, which are formulated into the vaccines of the present invention.

  12. Artificial 64-Residue HIV-1 Enhancer-Binding Peptide Is a Potent Inhibitor of Viral Replication in HIV-1-Infected Cells

    Directory of Open Access Journals (Sweden)

    Mouhssin Oufir

    2011-01-01

    Full Text Available An artificial HIV-1 enhancer-binding peptide was extended by nine consecutive arginine residues at the C-terminus and by the nuclear localization signal of SV40 large T antigen at the N-terminus. The resulting synthetic 64-residue peptide was found to bind to the two enhancers of the HIV-1 long terminal repeat, cross the plasma membrane and the nuclear envelope of human cells, and suppress the HIV-1 enhancer-controlled expression of a green fluorescent protein reporter gene. Moreover, HIV-1 replication is inhibited by this peptide in HIV-1-infected CEM-GFP cells as revealed by HIV-1 p24 ELISA and real-time RT-PCR of HIV-1 RNA. Rapid uptake of this intracellular stable and inhibitory peptide into the cells implies that this peptide may have the potential to attenuate HIV-1 replication in vivo.

  13. BI-2 destabilizes HIV-1 cores during infection and Prevents Binding of CPSF6 to the HIV-1 Capsid.

    Science.gov (United States)

    Fricke, Thomas; Buffone, Cindy; Opp, Silvana; Valle-Casuso, Jose; Diaz-Griffero, Felipe

    2014-12-11

    The recently discovered small-molecule BI-2 potently blocks HIV-1 infection. BI-2 binds to the N-terminal domain of HIV-1 capsid. BI-2 utilizes the same capsid pocket used by the small molecule PF74. Although both drugs bind to the same pocket, it has been proposed that BI-2 uses a different mechanism to block HIV-1 infection when compared to PF74. This work demonstrates that BI-2 destabilizes the HIV-1 core during infection, and prevents the binding of the cellular factor CPSF6 to the HIV-1 core. Overall this short-form paper suggests that BI-2 is using a similar mechanism to the one used by PF74 to block HIV-1 infection.

  14. Coactivator-associated arginine methyltransferase 1 enhances transcriptional activity of the human T-cell lymphotropic virus type 1 long terminal repeat through direct interaction with Tax.

    Science.gov (United States)

    Jeong, Soo-Jin; Lu, Hanxin; Cho, Won-Kyung; Park, Hyeon Ung; Pise-Masison, Cynthia; Brady, John N

    2006-10-01

    In this study, we demonstrate that the coactivator-associated arginine methyltransferase 1 (CARM1), which methylates histone H3 and other proteins such as p300/CBP, is positively involved in the regulation of Tax transactivation. First, transfection studies demonstrated that overexpression of CARM1 wild-type protein resulted in increased Tax transactivation of the human T-cell lymphotropic virus type 1 (HTLV-1) long terminal repeat (LTR). In contrast, transfection of a catalytically inactive CARM1 methyltransferase mutant did not enhance Tax transactivation. CARM1 facilitated Tax transactivation of the CREB-dependent cellular GEM promoter. A direct physical interaction between HTLV-1 Tax and CARM1 was demonstrated using in vitro glutathione S-transferase-Tax binding assays, in vivo coimmunoprecipitation, and confocal microscopy experiments. Finally, chromatin immunoprecipitation analysis of the activated HTLV-1 LTR promoter showed the association of CARM1 and methylated histone H3 with the template DNA. In vitro, Tax facilitates the binding of CARM1 to the transcription complex. Together, our data provide evidence that CARM1 enhances Tax transactivation of the HTLV-1 LTR through a direct interaction between CARM1 and Tax and this binding promotes methylation of histone H3 (R2, R17, and R26).

  15. Phylogenetic analysis of HIV-1 pol gene: first subgenomic evidence of CRF29-BF among Iranian HIV-1 patients

    Directory of Open Access Journals (Sweden)

    Kazem Baesi

    2014-09-01

    Full Text Available Objective: To identify the dominant subtype among the HIV-1 strains circulation in Iran. Methods: In this cross sectional study 100 HIV positive patients participated. HIV-1 RNA was extracted from plasma. RT nested-PCR was performed and the final products were sequenced and phylogenetically analyzed; reference sequences were downloaded from Los Alamos, aligned with Iranian pol sequences in the study and analyzed by neighbor-joining method. Results: The results of the phylogenetic analysis showed that HIV-1 subtype CRF-35AD was the dominant subtype among HIV-1 infected patients in Iran; this analysis also suggested a new circulating recombinant form that had not previously been identified in Iran: CRF-29BF. Conclusions: The impact of HIV diversity on pathogenesis, transmission and clinical management have been discussed in different studies; therefore, analyses of HIV genetic diversity is required to design effective antiretroviral strategies for different HIV subtypes.

  16. German-austrian recommendations for HIV1-therapy in pregnancy and in HIV1-exposed newborn - update 2008

    Directory of Open Access Journals (Sweden)

    Buchholz Bernd

    2009-11-01

    Full Text Available Abstract German-Austrian recommendations for HIV1-therapy in pregnancy - Update 2008 Bernd Buchholz (University Medical Centre Mannheim, Pediatric Clinic, Matthias Beichert (Mannheim, Gynecology and Obstetrics Practice, Ulrich Marcus (Robert Koch Institute, Berlin, Thomas Grubert, Andrea Gingelmaier (Gynecology Clinic of the Ludwig Maximilians University of Munich, Dr. med. Annette Haberl (HIV-Department, J. W. Goethe-University Hospital, Frankfurt, Dr. med. Brigitte Schmied (Otto-Wagner Spital, Wien. In Germany during the last years about 200-250 HIV1-infected pregnant women delivered a baby each year, a number that is currently increasing. To determine the HIV-status early in pregnancy voluntary HIV-testing of all pregnant women is recommended in Germany and Austria as part of prenatal care. In those cases, where HIV1-infection was known during pregnancy, since 1995 the rate of vertical transmission of HIV1 was reduced to 1-2%. This low transmission rate has been achieved by the combination of anti-retroviral therapy of pregnant women, caesarean section scheduled before onset of labour, anti-retroviral post exposition prophylaxis in the newborn and refraining from breast-feeding by the HIV1-infected mother. To keep pace with new results in research, approval of new anti-retroviral drugs and changes in the general treatment recommendations for HIV1-infected adults, in 1998, 2001, 2003 and 2005 an interdisciplinary consensus meeting was held. Gynaecologists, infectious disease specialists, paediatricians, pharmacologists, virologists and members of the German AIDS Hilfe (NGO were participating in this conference to update the prevention strategies. A fifth update became necessary in 2008. The updating process was started in January 2008 and was terminated in September 2008. The guidelines provide new recommendations on the indication and the starting point for HIV-therapy in pregnancies without complications, drugs and drug combinations to be

  17. Genetic characterization of human T-cell lymphotropic virus type 1 in Mozambique: transcontinental lineages drive the HTLV-1 endemic.

    Directory of Open Access Journals (Sweden)

    Ana Carolina P Vicente

    2011-04-01

    Full Text Available Human T-Cell Lymphotropic Virus Type 1 (HTLV-1 is the etiological agent of adult T-cell leukemia (ATL and HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP. It has been estimated that 10-20 million people are infected worldwide, but no successful treatment is available. Recently, the epidemiology of this virus was addressed in blood donors from Maputo, showing rates from 0.9 to 1.2%. However, the origin and impact of HTLV endemic in this population is unknown.To assess the HTLV-1 molecular epidemiology in Mozambique and to investigate their relationship with HTLV-1 lineages circulating worldwide.Blood donors and HIV patients were screened for HTLV antibodies by using enzyme immunoassay, followed by Western Blot. PCR and sequencing of HTLV-1 LTR region were applied and genetic HTLV-1 subtypes were assigned by the neighbor-joining method. The mean genetic distance of Mozambican HTLV-1 lineages among the genetic clusters were determined. Human mitochondrial (mt DNA analysis was performed and individuals classified in mtDNA haplogroups.LTR HTLV-1 analysis demonstrated that all isolates belong to the Transcontinental subgroup of the Cosmopolitan subtype. Mozambican HTLV-1 sequences had a high inter-strain genetic distance, reflecting in three major clusters. One cluster is associated with the South Africa sequences, one is related with Middle East and India strains and the third is a specific Mozambican cluster. Interestingly, 83.3% of HIV/HTLV-1 co-infection was observed in the Mozambican cluster. The human mtDNA haplotypes revealed that all belong to the African macrohaplogroup L with frequencies representatives of the country.The Mozambican HTLV-1 genetic diversity detected in this study reveals that although the strains belong to the most prevalent and worldwide distributed Transcontinental subgroup of the Cosmopolitan subtype, there is a high HTLV diversity that could be correlated with at least 3 different HTLV-1 introductions

  18. DBR1 siRNA inhibition of HIV-1 replication

    Directory of Open Access Journals (Sweden)

    Naidu Yathi

    2005-10-01

    Full Text Available Abstract Background HIV-1 and all retroviruses are related to retroelements of simpler organisms such as the yeast Ty elements. Recent work has suggested that the yeast retroelement Ty1 replicates via an unexpected RNA lariat intermediate in cDNA synthesis. The putative genomic RNA lariat intermediate is formed by a 2'-5' phosphodiester bond, like that found in pre-mRNA intron lariats and it facilitates the minus-strand template switch during cDNA synthesis. We hypothesized that HIV-1 might also form a genomic RNA lariat and therefore that siRNA-mediated inhibition of expression of the human RNA lariat de-branching enzyme (DBR1 expression would specifically inhibit HIV-1 replication. Results We designed three short interfering RNA (siRNA molecules targeting DBR1, which were capable of reducing DBR1 mRNA expression by 80% and did not significantly affect cell viability. We assessed HIV-1 replication in the presence of DBR1 siRNA and found that DBR1 knockdown led to decreases in viral cDNA and protein production. These effects could be reversed by cotransfection of a DBR1 cDNA indicating that the inhibition of HIV-1 replication was a specific effect of DBR1 underexpression. Conclusion These data suggest that DBR1 function may be needed to debranch a putative HIV-1 genomic RNA lariat prior to completion of reverse transcription.

  19. HLA Class I-Mediated HIV-1 Control in Vietnamese Infected with HIV-1 Subtype A/E.

    Science.gov (United States)

    Chikata, Takayuki; Tran, Giang Van; Murakoshi, Hayato; Akahoshi, Tomohiro; Qi, Ying; Naranbhai, Vivek; Kuse, Nozomi; Tamura, Yoshiko; Koyanagi, Madoka; Sakai, Sachiko; Nguyen, Dung Hoai; Nguyen, Dung Thi; Nguyen, Ha Thu; Nguyen, Trung Vu; Oka, Shinichi; Martin, Maureen P; Carrington, Mary; Sakai, Keiko; Nguyen, Kinh Van; Takiguchi, Masafumi

    2018-03-01

    HIV-1-specific cytotoxic T cells (CTLs) play an important role in the control of HIV-1 subtype B or C infection. However, the role of CTLs in HIV-1 subtype A/E infection still remains unclear. Here we investigated the association of HLA class I alleles with clinical outcomes in treatment-naive Vietnamese infected with subtype A/E virus. We found that HLA-C*12:02 was significantly associated with lower plasma viral loads (pVL) and higher CD4 counts and that the HLA-A*29:01-B*07:05-C*15:05 haplotype was significantly associated with higher pVL and lower CD4 counts than those for individuals without these respective genotypes. Nine Pol and three Nef mutations were associated with at least one HLA allele in the HLA-A*29:01-B*07:05-C*15:05 haplotype, with a strong negative correlation between the number of HLA-associated Pol mutations and CD4 count as well as a positive correlation with pVL for individuals with these HLA alleles. The results suggest that the accumulation of mutations selected by CTLs restricted by these HLA alleles affects HIV control. IMPORTANCE Most previous studies on HLA association with disease progression after HIV-1 infection have been performed on cohorts infected with HIV-1 subtypes B and C, whereas few such population-based studies have been reported for cohorts infected with the Asian subtype A/E virus. In this study, we analyzed the association of HLA class I alleles with clinical outcomes for 536 HIV-1 subtype A/E-infected Vietnamese individuals. We found that HLA-C*12:02 is protective, while the HLA haplotype HLA-A*29:01-B*07:05-C*15:05 is deleterious. The individuals with HIV-1 mutations associated with at least one of the HLA alleles in the deleterious HLA haplotype had higher plasma viral loads and lower CD4 counts than those of individuals without the mutations, suggesting that viral adaptation and escape from HLA-mediated immune control occurred. The present study identifies a protective allele and a deleterious haplotype for HIV-1

  20. Differential effects of sex in a West African cohort of HIV-1, HIV-2 and HIV-1/2 dually infected patients: men are worse off.

    Science.gov (United States)

    Jespersen, Sanne; Hønge, Bo Langhoff; Esbjörnsson, Joakim; Medina, Candida; da Silva Té, David; Correira, Faustino Gomes; Laursen, Alex Lund; Østergaard, Lars; Andersen, Andreas; Aaby, Peter; Erikstrup, Christian; Wejse, Christian

    2016-02-01

    Several studies have reported conflicting effects of sex on HIV-1 infection. We describe differences in baseline characteristics and assess the impact of sex on HIV progression among patients at a clinic with many HIV-2 and HIV-1/2 dually infected patients. This study utilised a retrospective cohort of treatment-naïve adults at the largest HIV clinic in Guinea-Bissau from 6 June 2005 to 1 December 2013. Baseline characteristics were assessed and the patients followed until death, transfer, loss to follow-up, or 1 June 2014. We estimated the time from the first clinic visit until initiation of ART, death or loss to follow-up using Cox proportional hazard models. A total of 5694 patients were included in the study, 3702 women (65%) and 1992 men (35%). Women were more likely than men to be infected with HIV-2 (19% vs. 15%, P < 0.01) or dually infected with HIV-1/2 (11% vs. 9%, P = 0.02). For all HIV types, women were younger (median 35 vs. 40 years), less likely to have schooling (55% vs. 77%) or to be married (46% vs. 67%), and had higher baseline CD4 cell counts (median 214 vs. 178 cells/μl). Men had a higher age-adjusted mortality rate (hazard rate ratio (HRR) 1.29, 95% confidence interval (CI) 1.09-1.52) and were more often lost to follow-up (HRR 1.27, 95% CI 1.17-1.39). Significant differences exist between HIV-infected men and women regardless of HIV type. Men seek treatment at a later stage and, despite better socio-economic status, have higher mortality and loss to follow-up than women. © 2015 John Wiley & Sons Ltd.

  1. Rotavirus 2/6 Viruslike Particles Administered Intranasally with Cholera Toxin, Escherichia coli Heat-Labile Toxin (LT), and LT-R192G Induce Protection from Rotavirus Challenge

    Science.gov (United States)

    O’Neal, Christine M.; Clements, John D.; Estes, Mary K.; Conner, Margaret E.

    1998-01-01

    We have shown that rotavirus 2/6 viruslike particles composed of proteins VP2 and VP6 (2/6-VLPs) administered to mice intranasally with cholera toxin (CT) induced protection from rotavirus challenge, as measured by virus shedding. Since it is unclear if CT will be approved for human use, we evaluated the adjuvanticity of Escherichia coli heat-labile toxin (LT) and LT-R192G. Mice were inoculated intranasally with 10 μg of 2/6-VLPs combined with CT, LT, or LT-R192G. All three adjuvants induced equivalent geometric mean titers of rotavirus-specific serum antibody and intestinal immunoglobulin G (IgG). Mice inoculated with 2/6-VLPs with LT produced significantly higher titers of intestinal IgA than mice given CT as the adjuvant. All mice inoculated with 2/6-VLPs mixed with LT and LT-R192G were totally protected (100%) from rotavirus challenge, while mice inoculated with 2/6-VLPs mixed with CT showed a mean 91% protection from challenge. The availability of a safe, effective mucosal adjuvant such as LT-R192G will increase the practicality of administering recombinant vaccines mucosally. PMID:9525668

  2. Nursing and midwifery regulation and HIV scale-up: establishing a baseline in East, Central and Southern Africa.

    Science.gov (United States)

    McCarthy, Carey F; Voss, Joachim; Verani, Andre R; Vidot, Peggy; Salmon, Marla E; Riley, Patricia L

    2013-03-25

    Shifting HIV treatment tasks from physicians to nurses and midwives is essential to scaling-up HIV services in sub-Saharan Africa. Updating nursing and midwifery regulations to include task shifting and pre-service education reform can help facilitate reaching new HIV targets. Donor-supported initiatives to update nursing and midwifery regulations are increasing. However, there are gaps in our knowledge of current practice and education regulations and a lack of information to target and implement regulation strengthening efforts. We conducted a survey of national nursing and midwifery councils to describe current nursing and midwifery regulations in 13 African countries. A 30-item survey was administered to a convenience sample of 13 national nursing and midwifery regulatory body leaders in attendance at the PEPFAR-supported African Health Profession Regulatory Collaborative meeting in Nairobi, Kenya on 28 February, 2011. The survey contained questions on task shifting and regulations such as registration, licensure, scope of practice, pre-service education accreditation, continuing professional development and use of international guidelines. Survey data were analyzed to present country-level, comparative and regional findings. Task shifting to nurses and midwives was reported in 11 of the 13 countries. Eight countries updated their scope of practice within the last five years; only one reported their regulations to reflect task shifting. Countries vary with regard to licensure, pre-service accreditation and continuing professional development regulations in place. There was no consistency in terms of what standards were used to design national practice and education regulations. Many opportunities exist to assist countries to modernise regulations to incorporate important advancements from task shifting and pre-service reform. Appropriate, revised regulations can help sustain successful health workforce strategies and contribute to further scale-up HIV services

  3. The Natural Killer Cell Cytotoxic Function Is Modulated by HIV-1 Accessory Proteins

    Directory of Open Access Journals (Sweden)

    Edward Barker

    2011-07-01

    Full Text Available Natural killer (NK cells’ major role in the control of viruses is to eliminate established infected cells. The capacity of NK cells to kill virus-infected cells is dependent on the interactions between ligands on the infected cell and receptors on the NK cell surface. Because of the importance of ligand-receptor interactions in modulating the NK cell cytotoxic response, HIV has developed strategies to regulate various NK cell ligands making the infected cell surprisingly refractory to NK cell lysis. This is perplexing because the HIV-1 accessory protein Vpr induces expression of ligands for the NK cell activating receptor, NKG2D. In addition, the accessory protein Nef removes the inhibitory ligands HLA-A and -B. The reason for the ineffective killing by NK cells despite the strong potential to eliminate infected cells is due to HIV-1 Vpu’s ability to down modulate the co-activation ligand, NTB-A, from the cell surface. Down modulation of NTB-A prevents efficient NK cell degranulation. This review will focus on the mechanisms through which the HIV-1 accessory proteins modulate their respective ligands, and its implication for NK cell killing of HIV-infected cells.

  4. A real-time view of the TAR:Tat:P-TEFb complex at HIV-1 transcription sites

    Directory of Open Access Journals (Sweden)

    Knezevich Anna

    2007-05-01

    Full Text Available Abstract HIV-1 transcription is tightly regulated: silent in long-term latency and highly active in acutely-infected cells. Transcription is activated by the viral protein Tat, which recruits the elongation factor P-TEFb by binding the TAR sequence present in nascent HIV-1 RNAs. In this study, we analyzed the dynamic of the TAR:Tat:P-TEFb complex in living cells, by performing FRAP experiments at HIV-1 transcription sites. Our results indicate that a large fraction of Tat present at these sites is recruited by Cyclin T1. We found that in the presence of Tat, Cdk9 remained bound to nascent HIV-1 RNAs for 71s. In contrast, when transcription was activated by PMA/ionomycin, in the absence of Tat, Cdk9 turned-over rapidly and resided on the HIV-1 promoter for only 11s. Thus, the mechanism of trans-activation determines the residency time of P-TEFb at the HIV-1 gene, possibly explaining why Tat is such a potent transcriptional activator. In addition, we observed that Tat occupied HIV-1 transcription sites for 55s, suggesting that the TAR:Tat:P-TEFb complex dissociates from the polymerase following transcription initiation, and undergoes subsequent cycles of association/dissociation.

  5. Construction and characterization of HIV type 1 CRF07_BC infectious molecular clone from men who have sex with men.

    Science.gov (United States)

    Jiang, Yan-Ling; Bai, Wen-Wei; Qu, Fan-Wei; Ma, Hua; Jiang, Run-Sheng; Shen, Bao-Sheng

    2016-03-01

    This study aimed to investigate the biological characterization of HIV type 1 (HIV-1) CRF07_BC infection among men who have sex with men (MSM). From November 2011 to November 2013, a total of 66 blood samples were collected from MSM with acute HIV-1 infection with CRF07_BC subgroup strains. Deletion in the gag p6 region was detected by sequence alignment and comparative analysis. Peripheral blood mononuclear cells (PBMCs) of HNXX1301-1307 samples were separated by density gradient centrifugation. Nested polymerase chain reaction (nPCR) was used to amplify the viral DNA. The near full-length HIV-1 DNA products were ligated to the long terminal repeat (LTR) vector plasmid (07BCLTR) to construct a full-length HIV clone. The molecular clone was transfected into HEK-293T cells, TZM-b1 cells and patients' PBMCs. The pregenome of an infectious molecular clone of HIV-1 (pNL4-3) was amplified, and a subclone with CRF07_BC was developed to construct the full-length chimeric molecular clone pNL4-3/07BCLTR. Detection of p24 antigen and luciferase activity was used to measure the in vitro infectivity of pNL4-3/07BCLTR. Among the 66 MSM patients infected with CRF07_BC strains, deletion mutations of the Gag P6 proteins were found in 7 of 18CRF07_BC strains; deletion mutations of 2-13 amino acids in different regions were discovered in 6 strains; and the remaining 42 strains did not show deletions. Seven strains with amino acids deficiency in the P6 protein accounted for 27% of all strains and 75% of all deletion genotype strains. A total of 186 full-length molecular clones of CRF07_BC were constructed. There were 5, 9, 10 and 11 clones of HNXX1302, HNXX1304, HNXX1305 and HNXX1306 that resulted in p24-positive supernatant when transfected into HEK-293T cells. Full-length clones of HNXX1302, HNXX1304, HNXX1305 and HNXX1306 showed slight infection in the transfected TZM-b1 cells, as judged by the fluorescence values of TZM-b1 cells 48h post-transfection. However, we were unable to

  6. Dynamic range of Nef-mediated evasion of HLA class II-restricted immune responses in early HIV-1 infection.

    Science.gov (United States)

    Mahiti, Macdonald; Brumme, Zabrina L; Jessen, Heiko; Brockman, Mark A; Ueno, Takamasa

    2015-07-31

    HLA class II-restricted CD4(+) T lymphocytes play an important role in controlling HIV-1 replication, especially in the acute/early infection stage. But, HIV-1 Nef counteracts this immune response by down-regulating HLA-DR and up-regulating the invariant chain associated with immature HLA-II (Ii). Although functional heterogeneity of various Nef activities, including down-regulation of HLA class I (HLA-I), is well documented, our understanding of Nef-mediated evasion of HLA-II-restricted immune responses during acute/early infection remains limited. Here, we examined the ability of Nef clones from 47 subjects with acute/early progressive infection and 46 subjects with chronic progressive infection to up-regulate Ii and down-regulate HLA-DR and HLA-I from the surface of HIV-infected cells. HLA-I down-regulation function was preserved among acute/early Nef clones, whereas both HLA-DR down-regulation and Ii up-regulation functions displayed relatively broad dynamic ranges. Nef's ability to down-regulate HLA-DR and up-regulate Ii correlated positively at this stage, suggesting they are functionally linked in vivo. Acute/early Nef clones also exhibited higher HLA-DR down-regulation and lower Ii up-regulation functions compared to chronic Nef clones. Taken together, our results support enhanced Nef-mediated HLA class II immune evasion activities in acute/early compared to chronic infection, highlighting the potential importance of these functions following transmission. Copyright © 2015 Elsevier Inc. All rights reserved.

  7. Effects of human SAMHD1 polymorphisms on HIV-1 susceptibility

    International Nuclear Information System (INIS)

    White, Tommy E.; Brandariz-Nuñez, Alberto; Valle-Casuso, Jose Carlos; Knowlton, Caitlin; Kim, Baek; Sawyer, Sara L.; Diaz-Griffero, Felipe

    2014-01-01

    SAMHD1 is a human restriction factor that prevents efficient infection of macrophages, dendritic cells and resting CD4+ T cells by HIV-1. Here we explored the antiviral activity and biochemical properties of human SAMHD1 polymorphisms. Our studies focused on human SAMHD1 polymorphisms that were previously identified as evolving under positive selection for rapid amino acid replacement during primate speciation. The different human SAMHD1 polymorphisms were tested for their ability to block HIV-1, HIV-2 and equine infectious anemia virus (EIAV). All studied SAMHD1 variants block HIV-1, HIV-2 and EIAV infection when compared to wild type. We found that these variants did not lose their ability to oligomerize or to bind RNA. Furthermore, all tested variants were susceptible to degradation by Vpx, and localized to the nuclear compartment. We tested the ability of human SAMHD1 polymorphisms to decrease the dNTP cellular levels. In agreement, none of the different SAMHD1 variants lost their ability to reduce cellular levels of dNTPs. Finally, we found that none of the tested human SAMHD1 polymorphisms affected the ability of the protein to block LINE-1 retrotransposition. - Highlights: • Human SAMHD1 single-nucleotide polymorphisms block HIV-1 and HIV-2 infection. • SAMHD1 polymorphisms do not affect its ability to block LINE-1 retrotransposition. • SAMHD1 polymorphisms decrease the cellular levels of dNTPs

  8. Effects of human SAMHD1 polymorphisms on HIV-1 susceptibility

    Energy Technology Data Exchange (ETDEWEB)

    White, Tommy E.; Brandariz-Nuñez, Alberto; Valle-Casuso, Jose Carlos [Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, 1301 Morris Park – Price Center 501, New York, NY 10461 (United States); Knowlton, Caitlin; Kim, Baek [Department of Microbiology and Immunology, University of Rochester School of Medicine and Dentistry, Rochester, NY 14642 (United States); Sawyer, Sara L. [Department of Molecular Biosciences, University of Texas at Austin, Austin, TX 78712 (United States); Diaz-Griffero, Felipe, E-mail: Felipe.Diaz-Griffero@einstein.yu.edu [Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, 1301 Morris Park – Price Center 501, New York, NY 10461 (United States)

    2014-07-15

    SAMHD1 is a human restriction factor that prevents efficient infection of macrophages, dendritic cells and resting CD4+ T cells by HIV-1. Here we explored the antiviral activity and biochemical properties of human SAMHD1 polymorphisms. Our studies focused on human SAMHD1 polymorphisms that were previously identified as evolving under positive selection for rapid amino acid replacement during primate speciation. The different human SAMHD1 polymorphisms were tested for their ability to block HIV-1, HIV-2 and equine infectious anemia virus (EIAV). All studied SAMHD1 variants block HIV-1, HIV-2 and EIAV infection when compared to wild type. We found that these variants did not lose their ability to oligomerize or to bind RNA. Furthermore, all tested variants were susceptible to degradation by Vpx, and localized to the nuclear compartment. We tested the ability of human SAMHD1 polymorphisms to decrease the dNTP cellular levels. In agreement, none of the different SAMHD1 variants lost their ability to reduce cellular levels of dNTPs. Finally, we found that none of the tested human SAMHD1 polymorphisms affected the ability of the protein to block LINE-1 retrotransposition. - Highlights: • Human SAMHD1 single-nucleotide polymorphisms block HIV-1 and HIV-2 infection. • SAMHD1 polymorphisms do not affect its ability to block LINE-1 retrotransposition. • SAMHD1 polymorphisms decrease the cellular levels of dNTPs.

  9. Tye7 regulates yeast Ty1 retrotransposon sense and antisense transcription in response to adenylic nucleotides stress.

    Science.gov (United States)

    Servant, Géraldine; Pinson, Benoit; Tchalikian-Cosson, Aurélie; Coulpier, Fanny; Lemoine, Sophie; Pennetier, Carole; Bridier-Nahmias, Antoine; Todeschini, Anne Laure; Fayol, Hélène; Daignan-Fornier, Bertrand; Lesage, Pascale

    2012-07-01

    Transposable elements play a fundamental role in genome evolution. It is proposed that their mobility, activated under stress, induces mutations that could confer advantages to the host organism. Transcription of the Ty1 LTR-retrotransposon of Saccharomyces cerevisiae is activated in response to a severe deficiency in adenylic nucleotides. Here, we show that Ty2 and Ty3 are also stimulated under these stress conditions, revealing the simultaneous activation of three active Ty retrotransposon families. We demonstrate that Ty1 activation in response to adenylic nucleotide depletion requires the DNA-binding transcription factor Tye7. Ty1 is transcribed in both sense and antisense directions. We identify three Tye7 potential binding sites in the region of Ty1 DNA sequence where antisense transcription starts. We show that Tye7 binds to Ty1 DNA and regulates Ty1 antisense transcription. Altogether, our data suggest that, in response to adenylic nucleotide reduction, TYE7 is induced and activates Ty1 mRNA transcription, possibly by controlling Ty1 antisense transcription. We also provide the first evidence that Ty1 antisense transcription can be regulated by environmental stress conditions, pointing to a new level of control of Ty1 activity by stress, as Ty1 antisense RNAs play an important role in regulating Ty1 mobility at both the transcriptional and post-transcriptional stages.

  10. Cyclophilin B enhances HIV-1 infection

    Energy Technology Data Exchange (ETDEWEB)

    DeBoer, Jason; Madson, Christian J. [Department of Medical Microbiology and Immunology, Creighton University, Omaha, NE (United States); Belshan, Michael, E-mail: michaelbelshan@creighton.edu [Department of Medical Microbiology and Immunology, Creighton University, Omaha, NE (United States); The Nebraska Center for Virology, University of Nebraska, Lincoln, NE (United States)

    2016-02-15

    Cyclophilin B (CypB) is a member of the immunophilin family and intracellular chaperone. It predominantly localizes to the ER, but also contains a nuclear localization signal and is secreted from cells. CypB has been shown to interact with the Gag protein of human immunodeficiency type 1 (HIV-1). Several proteomic and genetic studies identified it as a potential factor involved in HIV replication. Herein, we show that over-expression of CypB enhances HIV infection by increasing nuclear import of viral DNA. This enhancement was unaffected by cyclosporine treatment and requires the N-terminus of the protein. The N-terminus contains an ER leader sequence, putative nuclear localization signal, and is required for secretion. Deletion of the N-terminus resulted in mislocalization from the ER and suppression of HIV infection. Passive transfer experiments showed that secreted CypB did not impact HIV infection. Combined, these experiments show that intracellular CypB modulates a pathway of HIV nuclear import. - Highlights: • CypB has been identified in several proteomic studies of HIV-1 infection. • CypB expression is upregulated in activated and infected T-cells. • Over-expression of CypB enhances HIV nuclear import and infection. • The N-terminus of CypB is necessary for these effects.

  11. Cyclophilin B enhances HIV-1 infection

    International Nuclear Information System (INIS)

    DeBoer, Jason; Madson, Christian J.; Belshan, Michael

    2016-01-01

    Cyclophilin B (CypB) is a member of the immunophilin family and intracellular chaperone. It predominantly localizes to the ER, but also contains a nuclear localization signal and is secreted from cells. CypB has been shown to interact with the Gag protein of human immunodeficiency type 1 (HIV-1). Several proteomic and genetic studies identified it as a potential factor involved in HIV replication. Herein, we show that over-expression of CypB enhances HIV infection by increasing nuclear import of viral DNA. This enhancement was unaffected by cyclosporine treatment and requires the N-terminus of the protein. The N-terminus contains an ER leader sequence, putative nuclear localization signal, and is required for secretion. Deletion of the N-terminus resulted in mislocalization from the ER and suppression of HIV infection. Passive transfer experiments showed that secreted CypB did not impact HIV infection. Combined, these experiments show that intracellular CypB modulates a pathway of HIV nuclear import. - Highlights: • CypB has been identified in several proteomic studies of HIV-1 infection. • CypB expression is upregulated in activated and infected T-cells. • Over-expression of CypB enhances HIV nuclear import and infection. • The N-terminus of CypB is necessary for these effects.

  12. Enrichment of intersubtype HIV-1 recombinants in a dual infection system using HIV-1 strain-specific siRNAs

    Science.gov (United States)

    2011-01-01

    Background Intersubtype HIV-1 recombinants in the form of unique or stable circulating recombinants forms (CRFs) are responsible for over 20% of infections in the worldwide epidemic. Mechanisms controlling the generation, selection, and transmission of these intersubtype HIV-1 recombinants still require further investigation. All intersubtype HIV-1 recombinants are generated and evolve from initial dual infections, but are difficult to identify in the human population. In vitro studies provide the most practical system to study mechanisms, but the recombination rates are usually very low in dual infections with primary HIV-1 isolates. This study describes the use of HIV-1 isolate-specific siRNAs to enrich intersubtype HIV-1 recombinants and inhibit the parental HIV-1 isolates from a dual infection. Results Following a dual infection with subtype A and D primary HIV-1 isolates and two rounds of siRNA treatment, nearly 100% of replicative virus was resistant to a siRNA specific for an upstream target sequence in the subtype A envelope (env) gene as well as a siRNA specific for a downstream target sequence in the subtype D env gene. Only 20% (10/50) of the replicating virus had nucleotide substitutions in the siRNA-target sequence whereas the remaining 78% (39/50) harbored a recombination breakpoint that removed both siRNA target sequences, and rendered the intersubtype D/A recombinant virus resistant to the dual siRNA treatment. Since siRNAs target the newly transcribed HIV-1 mRNA, the siRNAs only enrich intersubtype env recombinants and do not influence the recombination process during reverse transcription. Using this system, a strong bias is selected for recombination breakpoints in the C2 region, whereas other HIV-1 env regions, most notably the hypervariable regions, were nearly devoid of intersubtype recombination breakpoints. Sequence conservation plays an important role in selecting for recombination breakpoints, but the lack of breakpoints in many conserved

  13. Plasmacytoid dendritic cells accumulate and secrete interferon alpha in lymph nodes of HIV-1 patients.

    Directory of Open Access Journals (Sweden)

    Clara Lehmann

    2010-06-01

    Full Text Available Circulating plasmacytoid dendritic cells (pDC decline during HIV-1 infection, but at the same time they express markedly higher levels of interferon alpha (IFNalpha, which is associated with HIV-1 disease progression. Here we show an accumulation of pDC in lymph nodes (LN of treatment-naïve HIV-1 patients. This phenomenon was associated with elevated expression of the LN homing marker, CCR7, on pDC in peripheral blood of HIV-1 patients, which conferred increased migratory capacity in response to CCR7 ligands in ex vivo functional assays. LN-homed pDC of HIV-1 patients presented higher CD40 and lower BDCA2 levels, but unchanged CD83 and CD86 expression. In addition, these cells expressed markedly higher amounts of IFNalpha compared to uninfected individuals, and were undergoing faster rates of cell death. These results demonstrate for the first time that in asymptomatic, untreated HIV-1 patients circulating pDC up-regulate CCR7 expression, accumulate in lymph nodes, and express high amounts of IFNalpha before undergoing cell death. Since IFNalpha inhibits cell proliferation and modulates immune responses, chronically high levels of this cytokine in LN of HIV-1 patients may impair differentiation and immune function of bystander CD4(+ T cells, thus playing into the mechanisms of AIDS immunopathogenesis.

  14. Cardiac Dysfunction in HIV-1 Transgenic Mouse: Role of Stress and BAG3.

    Science.gov (United States)

    Cheung, Joseph Y; Gordon, Jennifer; Wang, JuFang; Song, Jianliang; Zhang, Xue-Qian; Tilley, Douglas G; Gao, Erhe; Koch, Walter J; Rabinowitz, Joseph; Klotman, Paul E; Khalili, Kamel; Feldman, Arthur M

    2015-08-01

    Since highly active antiretroviral therapy improved long-term survival of acquired immunodeficiency syndrome (AIDS) patients, AIDS cardiomyopathy has become an increasingly relevant clinical problem. We used human immunodeficiency virus (HIV)-1 transgenic (Tg26) mouse to explore molecular mechanisms of AIDS cardiomyopathy. Tg26 mice had significantly lower left ventricular (LV) mass and smaller end-diastolic and end-systolic LV volumes. Under basal conditions, cardiac contractility and relaxation and single myocyte contraction dynamics were not different between wild-type (WT) and Tg26 mice. Ten days after open heart surgery, contractility and relaxation remained significantly depressed in Tg26 hearts, suggesting that Tg26 mice did not tolerate surgical stress well. To simulate heart failure in which expression of Bcl2-associated athanogene 3 (BAG3) is reduced, we down-regulated BAG3 by small hairpin ribonucleic acid in WT and Tg26 hearts. BAG3 down-regulation significantly reduced contractility in Tg26 hearts. BAG3 overexpression rescued contractile abnormalities in myocytes expressing the HIV-1 protein Tat. We conclude: (i) Tg26 mice exhibit normal contractile function at baseline; (ii) Tg26 mice do not tolerate surgical stress well; (iii) BAG3 down-regulation exacerbated cardiac dysfunction in Tg26 mice; (iv) BAG3 overexpression rescued contractile abnormalities in myocytes expressing HIV-1 protein Tat; and (v) BAG3 may occupy a role in pathogenesis of AIDS cardiomyopathy. © 2015 Wiley Periodicals, Inc.

  15. Modulation of HIV replication in monocyte derived macrophages (MDM) by steroid hormones.

    Science.gov (United States)

    Devadas, Krishnakumar; Biswas, Santanu; Ragupathy, Viswanath; Lee, Sherwin; Dayton, Andrew; Hewlett, Indira

    2018-01-01

    Significant sex specific differences in the progression of HIV/AIDS have been reported. Several studies have implicated steroid hormones in regulating host factor expression and modulating HIV transmission and replication. However, the exact mechanism exerted by steroid hormones estrogen and progesterone in the regulation of HIV-1 replication is still unclear. Results from the current study indicated a dose dependent down regulation of HIV-1 replication in monocyte derived macrophages pre-treated with high concentrations of estrogen or progesterone. To elucidate the molecular mechanisms associated with the down regulation of HIV-1 replication by estrogen and progesterone we used PCR arrays to analyze the expression profile of host genes involved in antiviral responses. Several chemokines, cytokines, transcription factors, interferon stimulated genes and genes involved in type-1 interferon signaling were down regulated in cells infected with HIV-1 pre-treated with high concentrations of estrogen or progesterone compared to untreated HIV-1 infected cells or HIV-1 infected cells treated with low concentrations of estrogen or progesterone. The down regulation of CXCL9, CXCL10 and CXCL11 chemokines and IL-1β, IL-6 cytokines in response to high concentrations of estrogen and progesterone pre-treatment in HIV-1 infected cells was confirmed at the protein level by quantitating chemokine and cytokine concentrations in the culture supernatant. These results demonstrate that a potent anti-inflammatory response is mediated by pre-treatment with high concentrations of estrogen and progesterone. Thus, our study suggests a strong correlation between the down-modulation of anti-viral and pro-inflammatory responses mediated by estrogen and progesterone pre-treatment and the down regulation of HIV-1 replication. These findings may be relevant to clinical observations of sex specific differences in patient populations and point to the need for further investigation.

  16. Characteristics of HIV-1 discordant couples enrolled in a trial of HSV-2 suppression to reduce HIV-1 transmission: the partners study.

    Directory of Open Access Journals (Sweden)

    Jairam R Lingappa

    Full Text Available The Partners HSV-2/HIV-1 Transmission Study (Partners Study is a phase III, placebo-controlled trial of daily acyclovir for genital herpes (HSV-2 suppression among HIV-1/HSV-2 co-infected persons to reduce HIV-1 transmission to their HIV-1 susceptible partners, which requires recruitment of HIV-1 serodiscordant heterosexual couples. We describe the baseline characteristics of this cohort.HIV-1 serodiscordant heterosexual couples, in which the HIV-1 infected partner was HSV-2 seropositive, had a CD4 count >or=250 cells/mcL and was not on antiretroviral therapy, were enrolled at 14 sites in East and Southern Africa. Demographic, behavioral, clinical and laboratory characteristics were assessed.Of the 3408 HIV-1 serodiscordant couples enrolled, 67% of the HIV-1 infected partners were women. Couples had cohabitated for a median of 5 years (range 2-9 with 28% reporting unprotected sex in the month prior to enrollment. Among HIV-1 susceptible participants, 86% of women and 59% of men were HSV-2 seropositive. Other laboratory-diagnosed sexually transmitted infections were uncommon (500 relative to <350, respectively, p<0.001.The Partners Study successfully enrolled a cohort of 3408 heterosexual HIV-1 serodiscordant couples in Africa at high risk for HIV-1 transmission. Follow-up of this cohort will evaluate the efficacy of acyclovir for HSV-2 suppression in preventing HIV-1 transmission and provide insights into biological and behavioral factors determining heterosexual HIV-1 transmission.ClinicalTrials.gov NCT00194519.

  17. Knowledge About HIV / AIDS: The Influence of Lifestyles and Self-Regulation in Adolescents

    Directory of Open Access Journals (Sweden)

    Claudia Balula Chaves

    2013-12-01

    Full Text Available Adolescents’ vulnerability to HIV/AIDS infection arises from their immaturity, sexual risk behaviours as well as factors of a social, economic, cultural and gender nature. Adolescence is a stage of the lifecycle in which managing constant and daily temptations and gaining and maintaining healthy lifestyles are difficult tasks and a test of the powers of self-regulation. The purpose of the study is to analyze the relationship between socio-demographic variables, school context, lifestyles, self-regulation skills and knowledge about HIV/AIDS in adolescents in secondary education in Portugal. A quantitative, cross-sectional, analytical, descriptive and correlational study with a sample of 971 adolescents in secondary education was conducted. The evaluation protocol includes a socio-demographic questionnaire, the school context, lifestyles, the Reduced Questionnaire of Self-regulation, Knowledge About AIDS Scale for Adolescents. The sample consisted of 50.80% boys and 49.20% girls, 43.40% of the adolescents with or less than 16 years, 66.40% residing in rural areas and 77.30% cohabiting with parents. The correlations indicate that among adolescents’ knowledge about AIDS and the subscale setting goals there is a positive and significant correlation (r = 0.224, p = 0.000, as well as the overall value of the Self-regulation Scale. Significant and negative correlations are presented for the impulse control subscale (r = -0.257, p = 0.000 and not significant to the overall self-regulation value (r = -0.041, p = 0.099, ranging in reverse, meaning that more knowledge about AIDS, better self-regulation with regard to impulses subscale. Self-regulated behaviour requires control of immediate needs, mobilization of thoughts, feelings and behaviours for purposes of long-term health, especially with regard to the prevention of HIV/AIDS.

  18. Mother-to-Child HIV-1 Transmission Events Are Differentially Impacted by Breast Milk and Its Components from HIV-1-Infected Women.

    Directory of Open Access Journals (Sweden)

    Ruizhong Shen

    Full Text Available Breast milk is a vehicle of infection and source of protection in post-natal mother-to-child HIV-1 transmission (MTCT. Understanding the mechanism by which breast milk limits vertical transmission will provide critical insight into the design of preventive and therapeutic approaches to interrupt HIV-1 mucosal transmission. However, characterization of the inhibitory activity of breast milk in human intestinal mucosa, the portal of entry in postnatal MTCT, has been constrained by the limited availability of primary mucosal target cells and tissues to recapitulate mucosal transmission ex vivo. Here, we characterized the impact of skimmed breast milk, breast milk antibodies (Igs and non-Ig components from HIV-1-infected Ugandan women on the major events of HIV-1 mucosal transmission using primary human intestinal cells and tissues. HIV-1-specific IgG antibodies and non-Ig components in breast milk inhibited the uptake of Ugandan HIV-1 isolates by primary human intestinal epithelial cells, viral replication in and transport of HIV-1- bearing dendritic cells through the human intestinal mucosa. Breast milk HIV-1-specific IgG and IgA, as well as innate factors, blocked the uptake and transport of HIV-1 through intestinal mucosa. Thus, breast milk components have distinct and complementary effects in reducing HIV-1 uptake, transport through and replication in the intestinal mucosa and, therefore, likely contribute to preventing postnatal HIV-1 transmission. Our data suggests that a successful preventive or therapeutic approach would require multiple immune factors acting at multiple steps in the HIV-1 mucosal transmission process.

  19. HIV-1 Non-Nucleoside Reverse Transcriptase Inhibitors

    DEFF Research Database (Denmark)

    Vanangamudi, Murugesan; Poongavanam, Vasanthanathan; Namasivayam, Vigneshwaran

    2017-01-01

    BACKGROUND: Design of inhibitors for HIV-1 reverse transcriptase inhibition (HIV-1 RT) is one of the successful chemotherapies for the treatment of HIV infection. Among the inhibitors available for HIV-1 RT, non-nucleoside reverse transcriptase inhibitors (NNRTIs) have shown to be very promising......: The conformation dependent-alignment based (CoMFA and CoMSIA) methods have been proven very successful ligand based strategy in the drug design. Here, CoMFA and CoMSIA studies reported for structurally distinct NNRTIs including thiazolobenzimidazole, dipyridodiazepinone, 1,1,3-trioxo [1,2,4]-thiadiazine...

  20. Socio-demographic and epidemiological characteristics associated with human immunodeficiency virus type I (HIV-1 infection in HIV-1-explosed but uninfected individuals, and in HIV-1-infected patients from a southern brasilian population Características sociodemográficas e epidemiológicas associadas com a infecção pelo vírus da imunodeficiência humana tipo 1 (HIV-1 em indivíduos expostos ao HIV-1 mas não infectados e em pacientes infectados pelo HIV-1, provenientes da população da região Sul do Brasil

    Directory of Open Access Journals (Sweden)

    Edna Maria Vissoci Reiche

    2005-10-01

    Full Text Available The ability to control human immunodeficiency virus type 1 (HIV-1 infection and progression of the disease is regulated by host and viral factors. This cross-sectional study describes the socio-demographic and epidemiological characteristics associated with HIV-1 infection in 1,061 subjects attended in Londrina and region, south of Brazil: 136 healthy individuals (Group 1, 147 HIV-1-exposed but uninfected individuals (Group 2, 161 HIV-1-infected asymptomatic patients (Group 3, and 617 patients with AIDS (Group 4. Data were obtained by a standardized questionnaire and serological tests. The age of the individuals ranged from 15.1 to 79.5 years, 54.0% and 56.1% of the Groups 3 and 4 patients, respectively, were men. The major features of groups 2, 3, and 4 were a predominance of education level up to secondary school (55.8%, 60.2% and 62.4%, respectively, sexual route of exposure (88.4%, 87.0% and 82.0%, respectively, heterosexual behavior (91.8%, 75.2% and 83.7%, respectively, and previous sexually transmitted diseases (20.4%, 32.5%, and 38.1%, respectively. The patients with AIDS showed the highest rates of seropositivity for syphilis (25.6%, of anti-HCV (22.3%, and anti-HTLV I/II obtained by two serological screening tests (6.2% and 6.8%, respectively. The results documenting the predominant characteristics for HIV-1 infection among residents of Londrina and region, could be useful for the improvement of current HIV-1 prevention, monitoring and therapeutic programs targeted at this population.Este estudo transversal descreve as principais características sociodemográficas e epidemiológicas associadas com a infecção pelo HIV-1 em 1.061 indivíduos atendidos em Londrina e região, Sul do Brasil: 136 indivíduos saudáveis (Grupo 1, 147 indivíduos expostos ao HIV-1 mas não infectados (Grupo 2, 161 pacientes infectados pelo HIV-1 assintomáticos (Grupo 3 e 617 pacientes com aids (Grupo 4. Os dados foram obtidos pela aplicação de um

  1. Dynamics of Preferential Substrate Recognition in HIV-1 Protease: Redefining the Substrate Envelope

    Science.gov (United States)

    Özen, Ayşegül; Haliloğlu, Türkan; Schiffer, Celia A.

    2011-01-01

    HIV-1 protease (PR) permits viral maturation by processing the Gag and Gag-Pro-Pol polyproteins. Though HIV-1 PR inhibitors (PIs) are used in combination antiviral therapy, the emergence of drug resistance has limited their efficacy. The rapid evolution of HIV-1 necessitates the consideration of drug resistance in novel drug-design strategies. Drug-resistant HIV-1 PR variants, while no longer efficiently inhibited, continue to efficiently hydrolyze the natural viral substrates. Though highly diverse in sequence, the HIV-1 PR substrates bind in a conserved three-dimensional shape we defined as the “substrate envelope”. We previously showed that resistance mutations arise where PIs protrude beyond the substrate envelope, as these regions are crucial for drug binding but not for substrate recognition. Here, we extend this model by considering the role of protein dynamics in the interaction of HIV-1 PR with its substrates. Seven molecular dynamics simulations of PR-substrate complexes were performed to estimate the conformational flexibility of substrates in their complexes. Interdependency of the substrate-protease interactions may compensate for the variations in cleavage-site sequences, and explain how a diverse set of sequences can be recognized as substrates by the same enzyme. This diversity may be essential for regulating sequential processing of substrates. We also define a dynamic substrate envelope as a more accurate representation of PR-substrate interactions. This dynamic substrate envelope, described by a probability distribution function, is a powerful tool for drug design efforts targeting ensembles of resistant HIV-1 PR variants with the aim of developing drugs that are less susceptible to resistance. PMID:21762811

  2. HIV-1 intersection with CD4 T cell vesicle exocytosis: intercellular communication goes viral

    Directory of Open Access Journals (Sweden)

    Helena eSoares

    2014-09-01

    Full Text Available In cells of the immune system the secretion of extracellular vesicles is modulated through cellular activation. In particular, T cell activation is achieved through cell-cell contacts with antigen presenting cells and the consequent formation of a specialized signaling junction called the immunological synapse. Recent works on CD4 T cells have elucidated that cognate antigen recognition by the T cell receptor (TCR engages two distinct exocytic events. The first, involves the exocytic targeting of signaling molecules at the synaptic membrane and drives the functional architecture of the immunological synapse. The second, enlists the extracellular secretion of the TCR itself, once the functional architecture of the immunological synapse is accomplished. HIV-1, a human lymphotropic virus, has evolved sophisticated mechanisms to co-opt CD4 T cell physiology. Notably, it has become apparent that HIV-1 intersects the regulated secretory system of CD4 T cells in order to bud from the plasma membrane of the infected cell and to promote bystander cell death. Here, I review the relevance of CD4 vesicle exocytosis to immune regulation and to HIV-1 pathogenesis and discuss their potential therapeutic applications.

  3. Inhibitory effects of (-)-epigallocatechin gallate on the life cycle of human immunodeficiency virus type 1 (HIV-1).

    Science.gov (United States)

    Yamaguchi, Koushi; Honda, Mitsuo; Ikigai, Hajime; Hara, Yukihiko; Shimamura, Tadakatsu

    2002-01-01

    Epigallocatechin gallate (EGCg), the major tea catechin, is known as a potent anti-bacterial agent. In addition, anti-tumor promoting, anti-inflammatory, anti-oxidative and antiviral activities have been reported. In the present study, we investigated possible anti-human immunodeficiency virus type-1 (HIV-1) activity of EGCg and its mechanisms of action in the viral life cycle. EGCg impinges on each step of the HIV life cycle. Thus, destruction of the viral particles, viral attachment to cells, post-adsorption entry into cells, reverse transcription (RT), viral production from chronically-infected cells, and the level of expression of viral mRNA, were analyzed using T-lymphoid (H9) and monocytoid (THP-1) cell systems, and antiviral protease activity was measured using a cell-free assay. Inhibitory effects of EGCg on specific binding of the virions to the cellular surfaces and changes in the steady state viral regulation (mRNA expression) due to EGCg were not observed. However, EGCg had a destructive effect on the viral particles, and post-adsorption entry and RT in acutely infected monocytoid cells were significantly inhibited at concentrations of EGCg greater than 1 microM, and protease kinetics were suppressed at a concentration higher than 10 microM in the cell-free study. Viral production by THP-1 cells chronically-infected with HIV-1 was also inhibited in a dose-dependent manner and the inhibitory effect was enhanced by liposome modification of EGCg. As expected, increased viral mRNA production was observed in lipopolysaccharide (LPS)-activated chronically HIV-1-infected cells. This production was significantly inhibited by EGCg treatment of THP-1 cells. In contrast, production of HIV-1 viral mRNA in unstimulated or LPS-stimulated T-lymphoid cells (H9) was not inhibited by EGCg. Anti-HIV viral activity of EGCg may thus result from an interaction with several steps in the HIV-1 life cycle.

  4. Nuclear retention of multiply spliced HIV-1 RNA in resting CD4+ T cells.

    Directory of Open Access Journals (Sweden)

    Kara G Lassen

    2006-07-01

    Full Text Available HIV-1 latency in resting CD4+ T cells represents a major barrier to virus eradication in patients on highly active antiretroviral therapy (HAART. We describe here a novel post-transcriptional block in HIV-1 gene expression in resting CD4+ T cells from patients on HAART. This block involves the aberrant localization of multiply spliced (MS HIV-1 RNAs encoding the critical positive regulators Tat and Rev. Although these RNAs had no previously described export defect, we show that they exhibit strict nuclear localization in resting CD4+ T cells from patients on HAART. Overexpression of the transcriptional activator Tat from non-HIV vectors allowed virus production in these cells. Thus, the nuclear retention of MS HIV-1 RNA interrupts a positive feedback loop and contributes to the non-productive nature of infection of resting CD4+ T cells. To define the mechanism of nuclear retention, proteomic analysis was used to identify proteins that bind MS HIV-1 RNA. Polypyrimidine tract binding protein (PTB was identified as an HIV-1 RNA-binding protein differentially expressed in resting and activated CD4+ T cells. Overexpression of PTB in resting CD4+ T cells from patients on HAART allowed cytoplasmic accumulation of HIV-1 RNAs. PTB overexpression also induced virus production by resting CD4+ T cells. Virus culture experiments showed that overexpression of PTB in resting CD4+ T cells from patients on HAART allowed release of replication-competent virus, while preserving a resting cellular phenotype. Whether through effects on RNA export or another mechanism, the ability of PTB to reverse latency without inducing cellular activation is a result with therapeutic implications.

  5. Differential effect of CLK SR Kinases on HIV-1 gene expression: potential novel targets for therapy

    Directory of Open Access Journals (Sweden)

    Dobson Wendy

    2011-06-01

    Full Text Available Abstract Background RNA processing plays a critical role in the replication of HIV-1, regulated in part through the action of host SR proteins. To explore the impact of modulating SR protein activity on virus replication, the effect of increasing or inhibiting the activity of the Cdc2-like kinase (CLK family of SR protein kinases on HIV-1 expression and RNA processing was examined. Results Despite their high homology, increasing individual CLK expression had distinct effects on HIV-1, CLK1 enhancing Gag production while CLK2 inhibited the virus. Parallel studies on the anti-HIV-1 activity of CLK inhibitors revealed a similar discrepant effect on HIV-1 expression. TG003, an inhibitor of CLK1, 2 and 4, had no effect on viral Gag synthesis while chlorhexidine, a CLK2, 3 and 4 inhibitor, blocked virus production. Chlorhexidine treatment altered viral RNA processing, decreasing levels of unspliced and single spliced viral RNAs, and reduced Rev accumulation. Subsequent experiments in the context of HIV-1 replication in PBMCs confirmed the capacity of chlorhexidine to suppress virus replication. Conclusions Together, these findings establish that HIV-1 RNA processing can be targeted to suppress virus replication as demonstrated by manipulating individual CLK function and identified chlorhexidine as a lead compound in the development of novel anti-viral therapies.

  6. The cytosolic exonuclease TREX1 inhibits the innate immune response to HIV-1

    Science.gov (United States)

    Yan, Nan; Regalado-Magdos, Ashton D.; Stiggelbout, Bart; Lee-Kirsch, Min Ae; Lieberman, Judy

    2010-01-01

    Viral infection triggers innate immune sensors to produce type I interferons (IFN). However, HIV infection of T cells and macrophages does not trip these alarms. How HIV avoids activating nucleic acid sensors is unknown. The cytosolic exonuclease TREX1 suppressed IFN triggered by HIV. In Trex1−/− mouse cells and human CD4+ T cells and macrophages in which TREX1 was inhibited by RNA interference, cytosolic HIV DNA accumulated, and HIV infection induced type I IFN that inhibited HIV replication and spreading. TREX1 bound to cytosolic HIV DNA and digested excess HIV DNA that would otherwise activate IFN expression via a TBK1, STING and IRF3 dependent pathway. HIV-stimulated IFN production in cells deficient in TREX1 did not involve known nucleic acid sensors. PMID:20871604

  7. Cocaine modulates HIV-1 integration in primary CD4+ T cells: implications in HIV-1 pathogenesis in drug-abusing patients

    Science.gov (United States)

    Addai, Amma B.; Pandhare, Jui; Paromov, Victor; Mantri, Chinmay K.; Pratap, Siddharth; Dash, Chandravanu

    2015-01-01

    Epidemiologic studies suggest that cocaine abuse worsens HIV-1 disease progression. Increased viral load has been suggested to play a key role for the accelerated HIV disease among cocaine-abusing patients. The goal of this study was to investigate whether cocaine enhances proviral DNA integration as a mechanism to increase viral load. We infected CD4+ T cells that are the primary targets of HIV-1 in vivo and treated the cells with physiologically relevant concentrations of cocaine (1 µM–100 µM). Proviral DNA integration in the host genome was measured by nested qPCR. Our results illustrated that cocaine from 1 µM through 50 µM increased HIV-1 integration in CD4+ T cells in a dose-dependent manner. As integration can be modulated by several early postentry steps of HIV-1 infection, we examined the direct effects of cocaine on viral integration by in vitro integration assays by use of HIV-1 PICs. Our data illustrated that cocaine directly increases viral DNA integration. Furthermore, our MS analysis showed that cocaine is able to enter CD4+ T cells and localize to the nucleus-. In summary, our data provide strong evidence that cocaine can increase HIV-1 integration in CD4+ T cells. Therefore, we hypothesize that increased HIV-1 integration is a novel mechanism by which cocaine enhances viral load and worsens disease progression in drug-abusing HIV-1 patients. PMID:25691383

  8. Exogenous HIV-1 Nef upsets the IFN-γ-induced impairment of human intestinal epithelial integrity.

    Directory of Open Access Journals (Sweden)

    Maria Giovanna Quaranta

    Full Text Available The mucosal tissues play a central role in the transmission of HIV-1 infection as well as in the pathogenesis of AIDS. Despite several clinical studies reported intestinal dysfunction during HIV infection, the mechanisms underlying HIV-induced impairments of mucosal epithelial barrier are still unclear. It has been postulated that HIV-1 alters enterocytic function and HIV-1 proteins have been detected in several cell types of the intestinal mucosa. In the present study, we analyzed the effect of the accessory HIV-1 Nef protein on human epithelial cell line.We used unstimulated or IFN-γ-stimulated Caco-2 cells, as a model for homeostatic and inflamed gastrointestinal tracts, respectively. We investigated the effect of exogenous recombinant Nef on monolayer integrity analyzing its uptake, transepithelial electrical resistance, permeability to FITC-dextran and the expression of tight junction proteins. Moreover, we measured the induction of proinflammatory mediators. Exogenous Nef was taken up by Caco-2 cells, increased intestinal epithelial permeability and upset the IFN-γ-induced reduction of transepithelial resistance, interfering with tight junction protein expression. Moreover, Nef inhibited IFN-γ-induced apoptosis and up-regulated TNF-α, IL-6 and MIP-3α production by Caco-2 cells while down-regulated IL-10 production. The simultaneous exposure of Caco-2 cells to Nef and IFN-γ did not affect cytokine secretion respect to untreated cells. Finally, we found that Nef counteracted the IFN-γ induced arachidonic acid cascade.Our findings suggest that exogenous Nef, perturbing the IFN-γ-induced impairment of intestinal epithelial cells, could prolong cell survival, thus allowing for accumulation of viral particles. Our results may improve the understanding of AIDS pathogenesis, supporting the discovery of new therapeutic interventions.

  9. APOBEC3G inhibits HIV-1 RNA elongation by inactivating the viral trans-activation response element.

    Science.gov (United States)

    Nowarski, Roni; Prabhu, Ponnandy; Kenig, Edan; Smith, Yoav; Britan-Rosich, Elena; Kotler, Moshe

    2014-07-29

    Deamination of cytidine residues in viral DNA is a major mechanism by which APOBEC3G (A3G) inhibits vif-deficient human immunodeficiency virus type 1 (HIV-1) replication. dC-to-dU transition following RNase-H activity leads to viral cDNA degradation, production of non-functional proteins, formation of undesired stop codons and decreased viral protein synthesis. Here, we demonstrate that A3G provides an additional layer of defense against HIV-1 infection dependent on inhibition of proviral transcription. HIV-1 transcription elongation is regulated by the trans-activation response (TAR) element, a short stem-loop RNA structure required for elongation factors binding. Vif-deficient HIV-1-infected cells accumulate short viral transcripts and produce lower amounts of full-length HIV-1 transcripts due to A3G deamination of the TAR apical loop cytidine, highlighting the requirement for TAR loop integrity in HIV-1 transcription. We further show that free single-stranded DNA (ssDNA) termini are not essential for A3G activity and a gap of CCC motif blocked with juxtaposed DNA or RNA on either or 3'+5' ends is sufficient for A3G deamination. These results identify A3G as an efficient mutator and that deamination of (-)SSDNA results in an early block of HIV-1 transcription. Copyright © 2014 Elsevier Ltd. All rights reserved.

  10. Development of an HIV-1 Subtype Panel in China: Isolation and Characterization of 30 HIV-1 Primary Strains Circulating in China.

    Directory of Open Access Journals (Sweden)

    Jingwan Han

    Full Text Available The complex epidemic and significant diversity of HIV-1 strains in China pose serious challenges for surveillance and diagnostic assays, vaccine development and clinical management. There is a lack of HIV-1 isolates in current canonical HIV-1 subtype panels that can represent HIV-1 diversity in China; an HIV-1 subtype panel for China is urgently needed.Blood samples were collected from HIV-1 infected patients participating in the drug-resistance surveillance program in China. The samples were isolated, cultured and stored as neat culture supernatant. The HIV-1 isolates were fully characterized. The panel was used to compare 2 viral load assays and 2 p24 assays as the examples of how this panel could be used.An HIV-1 subtype panel for China composed of 30 HIV-1 primary strains of four subtypes (B [including Thai-B], CRF01_AE, CRF07_BC and G was established. The samples were isolated and cultured to a high-titer (10(6-10(9 copies/ml/high-volume (40 ml. The HIV-1 isolates were fully characterized by the final viral load, p24 concentration, gag-pol and envC2V3 sequencing, co-receptor prediction, determination of the four amino acids at the tip of the env V3-loop, glycosylation sites in the V3 loop and the drug-resistance mutations. The comparison of two p24 assays and two viral load assays on the isolates illustrated how this panel may be used for the evaluation of diagnostic assay performance. The Pearson value between p24 assays were 0.938. The viral load results showed excellent concordance and agreement for samples of Thai-B, but lower correlations for samples of CRF01_AE.The current panel of 30 HIV-1 isolates served as a basis for the development of a comprehensive panel of fully characterized viral isolates, which could reflect the current dynamic and complex HIV-1 epidemic in China. This panel will be available to support HIV-1 research, assay evaluation, vaccine and drug development.

  11. HIV-1 Reservoir Association with Immune Activation

    Directory of Open Access Journals (Sweden)

    Alejandro Vallejo

    2015-09-01

    Full Text Available In this issue of EBioMedicine, Ruggiero and colleagues describe immune activation biomarkers associated with the size of the HIV reservoir in a carefully designed cross-sectional study. The cohort consists of a homogeneous sample of HIV-1-infected patients with long-term plasma HIV-1 RNA suppression under antiretroviral treatment (ART. It is crucial to explore the potential utility of biomarkers that are easier (less labor intensive, less expensive to measure than integrated HIV DNA load, in order to quickly and accurately quantify cellular reservoirs of HIV.

  12. Bond graph modeling and LQG/LTR controller design of magnetically levitation systems

    International Nuclear Information System (INIS)

    Kim, Jong Shik; Park, Jeon Soo

    1991-01-01

    A logical and systematic procedure to derive a mathematical model for magnetically levitation (MAGLEV) systems with a combined lift and guidance is developed by using bond graph modeling techniques. First, bond graph is contructed for the 1 st -dimensional MAGLEV system in which three subsystems (energy feeding, track and vehicle) are considered. And, the 2 nd -dimensional MAGLEV system in which lift and guidance dynamics are coupled is modeled by using the concept of multi-port field in bond graph languages. Finally, the LQG/LTR control system is designed for a multivariable MAGLEV system with stagger configuration type. In this paper, it has been shown that the bond graph is an excellent effective method for modeling multi-energy domain systems such as MAGLEV systems with uncertainties such as mass variations, track irregularities and wind gusts. (Author)

  13. Bond graph modeling and LQG/LTR controller design of magnetically levitation systems

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jong Shik; Park, Jeon Soo [Busan National Univ. (Korea, Republic of)

    1991-09-01

    A logical and systematic procedure to derive a mathematical model for magnetically levitation (MAGLEV) systems with a combined lift and guidance is developed by using bond graph modeling techniques. First, bond graph is contructed for the 1{sup st}-dimensional MAGLEV system in which three subsystems (energy feeding, track and vehicle) are considered. And, the 2{sup nd}-dimensional MAGLEV system in which lift and guidance dynamics are coupled is modeled by using the concept of multi-port field in bond graph languages. Finally, the LQG/LTR control system is designed for a multivariable MAGLEV system with stagger configuration type. In this paper, it has been shown that the bond graph is an excellent effective method for modeling multi-energy domain systems such as MAGLEV systems with uncertainties such as mass variations, track irregularities and wind gusts. (Author).

  14. Hepatitis B Virus Vaccination in HIV-1-Infected Young Adults: A Tool to Reduce the Size of HIV-1 Reservoirs?

    Science.gov (United States)

    Bekele, Yonas; Graham, Rebecka Lantto; Soeria-Atmadja, Sandra; Nasi, Aikaterini; Zazzi, Maurizio; Vicenti, Ilaria; Naver, Lars; Nilsson, Anna; Chiodi, Francesca

    2017-01-01

    During anti-retroviral therapy (ART) HIV-1 persists in cellular reservoirs, mostly represented by CD4+ memory T cells. Several approaches are currently being undertaken to develop a cure for HIV-1 infection through elimination (or reduction) of these reservoirs. Few studies have so far been conducted to assess the possibility of reducing the size of HIV-1 reservoirs through vaccination in virologically controlled HIV-1-infected children. We recently conducted a vaccination study with a combined hepatitis A virus (HAV) and hepatitis B virus (HBV) vaccine in 22 HIV-1-infected children. We assessed the size of the virus reservoir, measured as total HIV-1 DNA copies in blood cells, pre- and postvaccination. In addition, we investigated by immunostaining whether the frequencies of CD4+ and CD8+ T cells and parameters of immune activation and proliferation on these cells were modulated by vaccination. At 1 month from the last vaccination dose, we found that 20 out of 22 children mounted a serological response to HBV; a majority of children had antibodies against HAV at baseline. The number of HIV-1 DNA copies in blood at 1 month postvaccination was reduced in comparison to baseline although this reduction was not statistically significant. A significant reduction of HIV-1 DNA copies in blood following vaccination was found in 12 children. The frequencies of CD4+ (naïve, effector memory) and CD8+ (central memory) T-cell subpopulations changed following vaccinations and a reduction in the activation and proliferation pattern of these cells was also noticed. Multivariate linear regression analysis revealed that the frequency of CD8+ effector memory T cells prior to vaccination was strongly predictive of the reduction of HIV-1 DNA copies in blood following vaccination of the 22 HIV-1-infected children. The results of this study suggest a beneficial effect of vaccination to reduce the size of virus reservoir in HIV-1-infected children receiving ART. A reduced frequency of

  15. Hepatitis B Virus Vaccination in HIV-1-Infected Young Adults: A Tool to Reduce the Size of HIV-1 Reservoirs?

    Directory of Open Access Journals (Sweden)

    Yonas Bekele

    2018-01-01

    Full Text Available During anti-retroviral therapy (ART HIV-1 persists in cellular reservoirs, mostly represented by CD4+ memory T cells. Several approaches are currently being undertaken to develop a cure for HIV-1 infection through elimination (or reduction of these reservoirs. Few studies have so far been conducted to assess the possibility of reducing the size of HIV-1 reservoirs through vaccination in virologically controlled HIV-1-infected children. We recently conducted a vaccination study with a combined hepatitis A virus (HAV and hepatitis B virus (HBV vaccine in 22 HIV-1-infected children. We assessed the size of the virus reservoir, measured as total HIV-1 DNA copies in blood cells, pre- and postvaccination. In addition, we investigated by immunostaining whether the frequencies of CD4+ and CD8+ T cells and parameters of immune activation and proliferation on these cells were modulated by vaccination. At 1 month from the last vaccination dose, we found that 20 out of 22 children mounted a serological response to HBV; a majority of children had antibodies against HAV at baseline. The number of HIV-1 DNA copies in blood at 1 month postvaccination was reduced in comparison to baseline although this reduction was not statistically significant. A significant reduction of HIV-1 DNA copies in blood following vaccination was found in 12 children. The frequencies of CD4+ (naïve, effector memory and CD8+ (central memory T-cell subpopulations changed following vaccinations and a reduction in the activation and proliferation pattern of these cells was also noticed. Multivariate linear regression analysis revealed that the frequency of CD8+ effector memory T cells prior to vaccination was strongly predictive of the reduction of HIV-1 DNA copies in blood following vaccination of the 22 HIV-1-infected children. The results of this study suggest a beneficial effect of vaccination to reduce the size of virus reservoir in HIV-1-infected children receiving ART. A reduced

  16. Hepatitis B Virus Vaccination in HIV-1-Infected Young Adults: A Tool to Reduce the Size of HIV-1 Reservoirs?

    Science.gov (United States)

    Bekele, Yonas; Graham, Rebecka Lantto; Soeria-Atmadja, Sandra; Nasi, Aikaterini; Zazzi, Maurizio; Vicenti, Ilaria; Naver, Lars; Nilsson, Anna; Chiodi, Francesca

    2018-01-01

    During anti-retroviral therapy (ART) HIV-1 persists in cellular reservoirs, mostly represented by CD4+ memory T cells. Several approaches are currently being undertaken to develop a cure for HIV-1 infection through elimination (or reduction) of these reservoirs. Few studies have so far been conducted to assess the possibility of reducing the size of HIV-1 reservoirs through vaccination in virologically controlled HIV-1-infected children. We recently conducted a vaccination study with a combined hepatitis A virus (HAV) and hepatitis B virus (HBV) vaccine in 22 HIV-1-infected children. We assessed the size of the virus reservoir, measured as total HIV-1 DNA copies in blood cells, pre- and postvaccination. In addition, we investigated by immunostaining whether the frequencies of CD4+ and CD8+ T cells and parameters of immune activation and proliferation on these cells were modulated by vaccination. At 1 month from the last vaccination dose, we found that 20 out of 22 children mounted a serological response to HBV; a majority of children had antibodies against HAV at baseline. The number of HIV-1 DNA copies in blood at 1 month postvaccination was reduced in comparison to baseline although this reduction was not statistically significant. A significant reduction of HIV-1 DNA copies in blood following vaccination was found in 12 children. The frequencies of CD4+ (naïve, effector memory) and CD8+ (central memory) T-cell subpopulations changed following vaccinations and a reduction in the activation and proliferation pattern of these cells was also noticed. Multivariate linear regression analysis revealed that the frequency of CD8+ effector memory T cells prior to vaccination was strongly predictive of the reduction of HIV-1 DNA copies in blood following vaccination of the 22 HIV-1-infected children. The results of this study suggest a beneficial effect of vaccination to reduce the size of virus reservoir in HIV-1-infected children receiving ART. A reduced frequency of

  17. NMR Studies of the Structure and Function of the HIV-1 5′-Leader

    Directory of Open Access Journals (Sweden)

    Sarah C. Keane

    2016-12-01

    Full Text Available The 5′-leader of the human immunodeficiency virus type 1 (HIV-1 genome plays several critical roles during viral replication, including differentially establishing mRNA versus genomic RNA (gRNA fates. As observed for proteins, the function of the RNA is tightly regulated by its structure, and a common paradigm has been that genome function is temporally modulated by structural changes in the 5′-leader. Over the past 30 years, combinations of nucleotide reactivity mapping experiments with biochemistry, mutagenesis, and phylogenetic studies have provided clues regarding the secondary structures of stretches of residues within the leader that adopt functionally discrete domains. More recently, nuclear magnetic resonance (NMR spectroscopy approaches have been developed that enable direct detection of intra- and inter-molecular interactions within the intact leader, providing detailed insights into the structural determinants and mechanisms that regulate HIV-1 genome packaging and function.

  18. Curcumin derivatives as HIV-1 protease inhibitors

    Energy Technology Data Exchange (ETDEWEB)

    Sui, Z.; Li, J.; Craik, C.S.; Ortiz de Montellano, P.R. [Univ. of California, San Francisco, CA (United States)

    1993-12-31

    Curcumin, a non-toxic natural compound from Curcuma longa, has been found to be an HIV-1 protease inhibitor. Some of its derivatives were synthesized and their inhibitory activity against the HIV-1 protease was tested. Curcumin analogues containing boron enhanced the inhibitory activity. At least of the the synthesized compounds irreversibly inhibits the HIV-1 protease.

  19. Comparative transcriptome analysis of PBMC from HIV patients pre- and post-antiretroviral therapy

    DEFF Research Database (Denmark)

    Zhao, Fang-Jie; Ma, Jinmin; Huang, Lihua

    2017-01-01

    Infections of the human immunodeficiency virus (HIV) trigger host immune responses, but the virus can destroy the immune system and cause acquired immune deficiency syndrome (AIDS). Highly active antiretroviral therapy (HAART) can suppress viral replication and restore the impaired immune function......, minimum numbers of patients (one HIV alone; one HIV + tuberculosis, TB; one HIV + TB with immune reconstitution inflammatory syndrome during HAART) and two HIV negative volunteers were used. More than 15,000 gene transcripts were detected in each individual sample. Fourteen HAART up-regulated and eleven...... down-regulated DEGs were specifically identified in the HIV patients. Among them, nine up-regulated (CXCL1, S100P, AQP9, BASP1, MMP9, SOD2, LIMK2, IL1R2 and BCL2A1) and nine down-regulated DEGs (CD160, CD244, CX3CR1, IFIT1, IFI27, IFI44, IFI44L, MX1 and SIGLEC1) have already been reported as relevant...

  20. HIV-1 gp41 Fusion Intermediate: A Target for HIV Therapeutics

    Directory of Open Access Journals (Sweden)

    Chungen Pan

    2010-02-01

    Full Text Available Human immunodeficiency virus (HIV-1 infection is initiated by the binding of gp120 envelope glyco-protein to its cell receptor (CD4 and a coreceptor (CXCR4 or CCR5, followed by a series of conformational changes in the gp41 transmembrane subunit. These changes include insertion of fusion peptide into the target cell membrane and association of C-heptad repeat (CHR peptide with the N-heptad repeat (NHR trimer, a pre-hairpin fusion intermediate. A stable six-helix bundle core is then formed, bringing the viral envelope and target cell membrane into close proximity for fusion. Peptides derived from the CHR region, such as T20 and C34, inhibit HIV-1 fusion by interacting with the gp41 fusion intermediate. A number of anti-HIV-1 peptides and small molecule compounds targeting the gp41 NHR-trimer have been identified. By combining HIV fusion/entry inhibitors targeting different sites in the gp41 fusion intermediate, a potent synergistic effect takes place, resulting in a potential new therapeutic strategy for the HIV infection/AIDS. Here, we present an overview of the current development of anti-HIV drugs, particularly those targeting the gp41 fusion intermediate.

  1. Digoxin reveals a functional connection between HIV-1 integration preference and T-cell activation.

    Directory of Open Access Journals (Sweden)

    Alexander Zhyvoloup

    2017-07-01

    Full Text Available HIV-1 integrates more frequently into transcribed genes, however the biological significance of HIV-1 integration targeting has remained elusive. Using a selective high-throughput chemical screen, we discovered that the cardiac glycoside digoxin inhibits wild-type HIV-1 infection more potently than HIV-1 bearing a single point mutation (N74D in the capsid protein. We confirmed that digoxin repressed viral gene expression by targeting the cellular Na+/K+ ATPase, but this did not explain its selectivity. Parallel RNAseq and integration mapping in infected cells demonstrated that digoxin inhibited expression of genes involved in T-cell activation and cell metabolism. Analysis of >400,000 unique integration sites showed that WT virus integrated more frequently than N74D mutant within or near genes susceptible to repression by digoxin and involved in T-cell activation and cell metabolism. Two main gene networks down-regulated by the drug were CD40L and CD38. Blocking CD40L by neutralizing antibodies selectively inhibited WT virus infection, phenocopying digoxin. Thus the selectivity of digoxin depends on a combination of integration targeting and repression of specific gene networks. The drug unmasked a functional connection between HIV-1 integration and T-cell activation. Our results suggest that HIV-1 evolved integration site selection to couple its early gene expression with the status of target CD4+ T-cells, which may affect latency and viral reactivation.

  2. Digoxin reveals a functional connection between HIV-1 integration preference and T-cell activation.

    Science.gov (United States)

    Zhyvoloup, Alexander; Melamed, Anat; Anderson, Ian; Planas, Delphine; Lee, Chen-Hsuin; Kriston-Vizi, Janos; Ketteler, Robin; Merritt, Andy; Routy, Jean-Pierre; Ancuta, Petronela; Bangham, Charles R M; Fassati, Ariberto

    2017-07-01

    HIV-1 integrates more frequently into transcribed genes, however the biological significance of HIV-1 integration targeting has remained elusive. Using a selective high-throughput chemical screen, we discovered that the cardiac glycoside digoxin inhibits wild-type HIV-1 infection more potently than HIV-1 bearing a single point mutation (N74D) in the capsid protein. We confirmed that digoxin repressed viral gene expression by targeting the cellular Na+/K+ ATPase, but this did not explain its selectivity. Parallel RNAseq and integration mapping in infected cells demonstrated that digoxin inhibited expression of genes involved in T-cell activation and cell metabolism. Analysis of >400,000 unique integration sites showed that WT virus integrated more frequently than N74D mutant within or near genes susceptible to repression by digoxin and involved in T-cell activation and cell metabolism. Two main gene networks down-regulated by the drug were CD40L and CD38. Blocking CD40L by neutralizing antibodies selectively inhibited WT virus infection, phenocopying digoxin. Thus the selectivity of digoxin depends on a combination of integration targeting and repression of specific gene networks. The drug unmasked a functional connection between HIV-1 integration and T-cell activation. Our results suggest that HIV-1 evolved integration site selection to couple its early gene expression with the status of target CD4+ T-cells, which may affect latency and viral reactivation.

  3. Human cyclin T1 expression ameliorates a T-cell-specific transcriptional limitation for HIV in transgenic rats, but is not sufficient for a spreading infection of prototypic R5 HIV-1 strains ex vivo

    Directory of Open Access Journals (Sweden)

    Littman Dan R

    2009-01-01

    Full Text Available Abstract Background Cells derived from native rodents have limits at distinct steps of HIV replication. Rat primary CD4 T-cells, but not macrophages, display a profound transcriptional deficit that is ameliorated by transient trans-complementation with the human Tat-interacting protein Cyclin T1 (hCycT1. Results Here, we generated transgenic rats that selectively express hCycT1 in CD4 T-cells and macrophages. hCycT1 expression in rat T-cells boosted early HIV gene expression to levels approaching those in infected primary human T-cells. hCycT1 expression was necessary, but not sufficient, to enhance HIV transcription in T-cells from individual transgenic animals, indicating that endogenous cellular factors are critical co-regulators of HIV gene expression in rats. T-cells from hCD4/hCCR5/hCycT1-transgenic rats did not support productive infection of prototypic wild-type R5 HIV-1 strains ex vivo, suggesting one or more significant limitation in the late phase of the replication cycle in this primary rodent cell type. Remarkably, we identify a replication-competent HIV-1 GFP reporter strain (R7/3 YU-2 Env that displays characteristics of a spreading, primarily cell-to-cell-mediated infection in primary T-cells from hCD4/hCCR5-transgenic rats. Moreover, the replication of this recombinant HIV-1 strain was significantly enhanced by hCycT1 transgenesis. The viral determinants of this so far unique replicative ability are currently unknown. Conclusion Thus, hCycT1 expression is beneficial to de novo HIV infection in a transgenic rat model, but additional genetic manipulations of the host or virus are required to achieve full permissivity.

  4. Accumulation of MxB/Mx2-resistant HIV-1 Capsid Variants During Expansion of the HIV-1 Epidemic in Human Populations.

    Science.gov (United States)

    Wei, Wei; Guo, Haoran; Ma, Min; Markham, Richard; Yu, Xiao-Fang

    2016-06-01

    Recent studies have identified human myxovirus resistance protein 2 (MxB or Mx2) as an interferon induced inhibitor of HIV-1 replication. However, whether HIV-1 can overcome MxB restriction without compromise of viral fitness has been undefined. Here, we have discovered that naturally occurring capsid (CA) variants can render HIV-1 resistant to the activity of MxB without losing viral infectivity or the ability to escape from interferon induction. Moreover, these MxB resistant HIV-1 variants do not lose MxB recognition. Surprisingly, MxB resistant CA variants are most commonly found in the Clade C HIV-1 that is the most rapidly expanding Clade throughout the world. Accumulation of MxB resistant mutations is also observed during HIV-1 spreading in human populations. These findings support a potential role for MxB as a selective force during HIV-1 transmission and evolution. Copyright © 2016. Published by Elsevier B.V.

  5. [HIV-1 genetic variability in non Spaniard infected children].

    Science.gov (United States)

    Piñeiro Pérez, R; Mellado Peña, M J; Holguín, A; Cilleruelo, M J; García Hortelano, M; Villota, J; Martín Fontelos, P

    2009-01-01

    The prevalence of HIV-1 non-B subtypes (HIV-NBS) is increasing in Europe, because of emigration from countries where genetic variants are endemic. Although HIV-NBS could have a different clinical evolution and could respond differently to antiretrovirals (AR) than B-subtypes, these variant's response remain undocumented. To identify HIV-1 genetic variants and to determine clinical evolution in a non-Spaniard children infected with HIV-1. Children with HIV-1 infection from endemic countries were tested for HIV-1 subtypes between 1-1-1988 and 31-12-2006. Twelve children less than 18 years old and born abroad were selected. HIV-NBS were isolated in 5 children (42%): CRF2_AG recombinant in 3 cases (Equatorial Guinea), Subtype C in one (Equatorial Guinea) and CRF13_cpx in last one (India). Because of the increasing frequency of patients with HIV-NBS and their unknown long-term evolution, all children from endemic countries should be tested for HIV subtypes. We believe new studies with more patients during longer times could reveal differences in these patient's clinical, immunological and virological evolution.

  6. Comparison of the RealTime HIV-1, COBAS TaqMan 48 v1.0, Easy Q v1.2, and Versant v3.0 assays for Determination of HIV-1 Viral Loads in a Cohort of Canadian Patients with Diverse HIV Subtype Infections▿

    OpenAIRE

    Church, Deirdre; Gregson, Daniel; Lloyd, Tracie; Klein, Marina; Beckthold, Brenda; Laupland, Kevin; Gill, M. John

    2010-01-01

    HIV clinics in Canada provide care to an increasing number of patients born outside of Canada with HIV-1 non-B subtype infections. Because the Easy Q HIV-1 v1.2 assay (EQ; bioMérieux) failed to detect some non-B subtype infections, a multiassay HIV-1 viral load (VL) study was conducted with patients with diverse HIV subtype infections. Patients were enrolled from the Southern Alberta HIV Clinic (SAC), Calgary, Alberta, Canada (n = 349) and the McGill HIV Clinic (MHC), Montreal, Quebec, Canada...

  7. HBZ and its roles in HTLV-1 oncogenesis

    Directory of Open Access Journals (Sweden)

    Tiejun eZhao

    2012-07-01

    Full Text Available Human T-cell leukemia virus type 1 (HTLV-1 causes adult T-cell leukemia (ATL. The minus strand of HTLV-1 provirus encodes a bZIP protein donated as HTLV-1 bZIP factor (HBZ. Among the HTLV-1 regulatory and accessory genes, the tax and HBZ genes were thought to play critical roles in oncogenesis. However, HBZ is the only gene that remains intact and is consistently expressed in all ATL cases, while the tax gene is frequently inactivated by epigenetic modifications or deletion of the 5’LTR. HBZ gene promotes the proliferation of ATL cells through its mRNA form. Moreover, HBZ induces T-cell lymphoma and systemic inflammation in vivo. HBZ fulfills its functions mainly through regulating HTLV-1 5’LTR transcription and modulating a variety of cellular signaling pathways which are related with cell growth, immune response and T-cell differentiation. Taken together, the multiple functions of HBZ render its predominant function in leukemogenesis of ATL.

  8. HIV-1 viral load measurement in venous blood and fingerprick blood using Abbott RealTime HIV-1 DBS assay.

    Science.gov (United States)

    Tang, Ning; Pahalawatta, Vihanga; Frank, Andrea; Bagley, Zowie; Viana, Raquel; Lampinen, John; Leckie, Gregor; Huang, Shihai; Abravaya, Klara; Wallis, Carole L

    2017-07-01

    HIV RNA suppression is a key indicator for monitoring success of antiretroviral therapy. From a logistical perspective, viral load (VL) testing using Dried Blood Spots (DBS) is a promising alternative to plasma based VL testing in resource-limited settings. To evaluate the analytical and clinical performance of the Abbott RealTime HIV-1 assay using a fully automated one-spot DBS sample protocol. Limit of detection (LOD), linearity, lower limit of quantitation (LLQ), upper limit of quantitation (ULQ), and precision were determined using serial dilutions of HIV-1 Virology Quality Assurance stock (VQA Rush University), or HIV-1-containing armored RNA, made in venous blood. To evaluate correlation, bias, and agreement, 497 HIV-1 positive adult clinical samples were collected from Ivory Coast, Uganda and South Africa. For each HIV-1 participant, DBS-fingerprick, DBS-venous and plasma sample results were compared. Correlation and bias values were obtained. The sensitivity and specificity were analyzed at a threshold of 1000 HIV-1 copies/mL generated using the standard plasma protocol. The Abbott HIV-1 DBS protocol had an LOD of 839 copies/mL, a linear range from 500 to 1×10 7 copies/mL, an LLQ of 839 copies/mL, a ULQ of 1×10 7 copies/mL, and an inter-assay SD of ≤0.30 log copies/mL for all tested levels within this range. With clinical samples, the correlation coefficient (r value) was 0.896 between DBS-fingerprick and plasma and 0.901 between DBS-venous and plasma, and the bias was -0.07 log copies/mL between DBS-fingerprick and plasma and -0.02 log copies/mL between DBS-venous and plasma. The sensitivity of DBS-fingerprick and DBS-venous was 93%, while the specificity of both DBS methods was 95%. The results demonstrated that the Abbott RealTime HIV-1 assay with DBS sample protocol is highly sensitive, specific and precise across a wide dynamic range and correlates well with plasma values. The Abbott RealTime HIV-1 assay with DBS sample protocol provides an

  9. Diversity, distribution and dynamics of full-length Copia and Gypsy LTR retroelements in Solanum lycopersicum.

    Science.gov (United States)

    Paz, Rosalía Cristina; Kozaczek, Melisa Eliana; Rosli, Hernán Guillermo; Andino, Natalia Pilar; Sanchez-Puerta, Maria Virginia

    2017-10-01

    Transposable elements are the most abundant components of plant genomes and can dramatically induce genetic changes and impact genome evolution. In the recently sequenced genome of tomato (Solanum lycopersicum), the estimated fraction of elements corresponding to retrotransposons is nearly 62%. Given that tomato is one of the most important vegetable crop cultivated and consumed worldwide, understanding retrotransposon dynamics can provide insight into its evolution and domestication processes. In this study, we performed a genome-wide in silico search of full-length LTR retroelements in the tomato nuclear genome and annotated 736 full-length Gypsy and Copia retroelements. The dispersion level across the 12 chromosomes, the diversity and tissue-specific expression of those elements were estimated. Phylogenetic analysis based on the retrotranscriptase region revealed the presence of 12 major lineages of LTR retroelements in the tomato genome. We identified 97 families, of which 77 and 20 belong to the superfamilies Copia and Gypsy, respectively. Each retroelement family was characterized according to their element size, relative frequencies and insertion time. These analyses represent a valuable resource for comparative genomics within the Solanaceae, transposon-tagging and for the design of cultivar-specific molecular markers in tomato.

  10. Proteomic analysis of PBMCs: characterization of potential HIV-associated proteins

    Directory of Open Access Journals (Sweden)

    Yin Lin

    2010-03-01

    Full Text Available Abstract Background The human immunodeficiency virus type 1 (HIV-1 pandemic has continued unabated for nearly 30 years. To better understand the influence of virus on host cells, we performed the differential proteome research of peripheral blood mononuclear cells (PBMCs from HIV-positive patients and healthy controls. Results 26 protein spots with more than 1.5-fold difference were detected in two dimensional electrophoresis (2DE gels. 12 unique up-regulated and one down-regulated proteins were identified in HIV-positive patients compared with healthy donors. The mRNA expression of 10 genes was analyzed by real time RT-PCR. It shows that the mRNA expression of talin-1, vinculin and coronin-1C were up-regulated in HIV positive patients and consistent with protein expression. Western blotting analysis confirmed the induction of fragments of vinculin, talin-1 and filamin-A in pooled and most part of individual HIV-positive clinical samples. Bioinformatic analysis showed that a wide host protein network was disrupted in HIV-positive patients. Conclusions Together, this work provided useful information to facilitate further investigation of the underlying mechanism of HIV and host cell protein interactions, and discovered novel potential biomarkers such as fragment of vinculin, filamin-A and talin-1 for anti-HIV research.

  11. Sexually transmitted infections among HIV-1-discordant couples.

    Directory of Open Access Journals (Sweden)

    Brandon L Guthrie

    2009-12-01

    Full Text Available More new HIV-1 infections occur within stable HIV-1-discordant couples than in any other group in Africa, and sexually transmitted infections (STIs may increase transmission risk among discordant couples, accounting for a large proportion of new HIV-1 infections. Understanding correlates of STIs among discordant couples will aid in optimizing interventions to prevent HIV-1 transmission in these couples.HIV-1-discordant couples in which HIV-1-infected partners were HSV-2-seropositive were tested for syphilis, chlamydia, gonorrhea, and trichomoniasis, and HIV-1-uninfected partners were tested for HSV-2. We assessed sociodemographic, behavioral, and biological correlates of a current STI.Of 416 couples enrolled, 16% were affected by a treatable STI, and among these both partners were infected in 17% of couples. A treatable STI was found in 46 (11% females and 30 (7% males. The most prevalent infections were trichomoniasis (5.9% and syphilis (2.6%. Participants were 5.9-fold more likely to have an STI if their partner had an STI (P<0.01, and STIs were more common among those reporting any unprotected sex (OR = 2.43; P<0.01 and those with low education (OR = 3.00; P<0.01. Among HIV-1-uninfected participants with an HSV-2-seropositive partner, females were significantly more likely to be HSV-2-seropositive than males (78% versus 50%, P<0.01.Treatable STIs were common among HIV-1-discordant couples and the majority of couples affected by an STI were discordant for the STI, with relatively high HSV-2 discordance. Awareness of STI correlates and treatment of both partners may reduce HIV-1 transmission.ClinicalTrials.gov NCT00194519.

  12. Community study of the relative impact of HIV-1 and HIV-2 on intrathoracic tuberculosis

    DEFF Research Database (Denmark)

    Seng, R; Gustafson, P; Gomes, VF

    2002-01-01

    BACKGROUND: HIV-1 infection is associated with an increased incidence of and mortality from tuberculosis. Few community studies have examined the effect of HIV-2 on tuberculosis. METHODS: We investigated the association between HIV-1, HIV-2 and active tuberculosis in four districts (population 42...

  13. Structural Study of a New HIV-1 Entry Inhibitor and Interaction with the HIV-1 Fusion Peptide in Dodecylphosphocholine Micelles.

    Science.gov (United States)

    Pérez, Yolanda; Gómara, Maria José; Yuste, Eloísa; Gómez-Gutierrez, Patricia; Pérez, Juan Jesús; Haro, Isabel

    2017-08-25

    Previous studies support the hypothesis that the envelope GB virus C (GBV-C) E1 protein interferes the HIV-1 entry and that a peptide, derived from the region 139-156 of this protein, has been defined as a novel HIV-1 entry inhibitor. In this work, we firstly focus on the characterization of the structural features of this peptide, which are determinant for its anti-HIV-1 activity and secondly, on the study of its interaction with the proposed viral target (i.e., the HIV-1 fusion peptide). We report the structure of the peptide determined by NMR spectroscopy in dodecylphosphocholine (DPC) micelles solved by using restrained molecular dynamics calculations. The acquisition of different NMR experiments in DPC micelles (i.e., peptide-peptide titration, diffusion NMR spectroscopy, and addition of paramagnetic relaxation agents) allows a proposal of an inhibition mechanism. We conclude that a 18-mer peptide from the non-pathogenic E1 GBV-C protein, with a helix-turn-helix structure inhibits HIV-1 by binding to the HIV-1 fusion peptide at the membrane level, thereby interfering with those domains in the HIV-1, which are critical for stabilizing the six-helix bundle formation in a membranous environment. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. Correlation between HIV-1 genotype and clinical progression in HIV/AIDS patients in Surabaya, Indonesia

    Science.gov (United States)

    Rachman, B. E.; Khairunisa, S. Q.; Witaningrum, A. M.; Yunifiar, M. Q.; Nasronudin

    2018-03-01

    Several factors such as host and viral factors can affect the progression of HIV/AIDS. This study aims to identify the correlation viral factors, especially the HIV-1 subtype with HIV/AIDS progression. Inpatient HIV/AIDS during the period March to September 2017 and willing to participate are included in the study. Historical data of disease and treatment was taken by medical record. Blood samples were amplified, sequenced and undergone phylogenetic analysis. Linear regression analysis was used to estimate beta coefficient (β) and 95%CI of HIV/AIDS progression (measured by the CD4 change rate, ΔCD4 cell count/time span in months).This study has 17 samples. The HIV-1 subtype was dominated by CRF01_AE (81.8%) followed by subtype B (18.2%). There was significant correlation between subtype HIV-1 (p = 0.04) and body mass index (p = 0.038) with HIV/AIDS clinical stage. Many factors were assumed to be correlated with increased rate of CD4, but we only subtype HIV-1 had a significant correlation (p = 0.024) with it. From multivariate analysis, we also found that subtype HIV-1 had a significant correlation (β = 0.788, 95%CI: 17.5-38.6, p = 0.004).

  15. Characterization of natural polymorphic sites of the HIV-1 integrase before the introduction of HIV-1 integrase inhibitors in Germany

    Science.gov (United States)

    Meixenberger, Karolin; Pouran Yousef, Kaveh; Somogyi, Sybille; Fiedler, Stefan; Bartmeyer, Barbara; von Kleist, Max; Kücherer, Claudia

    2014-01-01

    Introduction The aim of our study was to analyze the occurrence and evolution of HIV-1 integrase polymorphisms during the HIV-1 epidemic in Germany prior to the introduction of the first integrase inhibitor raltegravir in 2007. Materials and Methods Plasma samples from drug-naïve HIV-1 infected individuals newly diagnosed between 1986 and 2006 were used to determine PCR-based population sequences of the HIV-1 integrase (amino acids 1–278). The HIV-1 subtype was determined using the REGA HIV-1 subtyping tool. We calculated the frequency of amino acids at each position of the HIV-1 integrase in 337 subtype B strains for the time periods 1986–1989, 1991–1994, 1995–1998, 1999–2002, and 2003–2006. Positions were defined as polymorphic if amino acid variation was >1% in any period. Logistic regression was used to identify trends in amino acid variation over time. Resistance-associated mutations were identified according to the IAS 2013 list and the HIVdb, ANRS and GRADE algorithms. Results Overall, 56.8% (158/278) amino acid positions were polymorphic and 15.8% (25/158) of these positions exhibited a significant trend in amino acid variation over time. Proportionately, most polymorphic positions (63.3%, 31/49) were detected in the N-terminal zinc finger domain of the HIV-1 integrase. Motifs and residues essential for HIV-1 integrase activity were little polymorphic, but within the minimal non-specific DNA binding region I220-D270 up to 18.1% amino acid variation was noticed, including four positions with significant amino acid variation over time (S230, D232, D256, A265). No major resistance mutations were identified, and minor resistance mutations were rarely observed without trend over time. E157Q considered by HIVdb, ANRS, and GRADE algorithms was the most frequent resistance-associated polymorphism with an overall prevalence of 2.4%. Conclusions Detailed knowledge of the evolutionary variation of HIV-1 integrase polymorphisms is important to understand

  16. Cyclophilin B enhances HIV-1 infection.

    Science.gov (United States)

    DeBoer, Jason; Madson, Christian J; Belshan, Michael

    2016-02-01

    Cyclophilin B (CypB) is a member of the immunophilin family and intracellular chaperone. It predominantly localizes to the ER, but also contains a nuclear localization signal and is secreted from cells. CypB has been shown to interact with the Gag protein of human immunodeficiency type 1 (HIV-1). Several proteomic and genetic studies identified it as a potential factor involved in HIV replication. Herein, we show that over-expression of CypB enhances HIV infection by increasing nuclear import of viral DNA. This enhancement was unaffected by cyclosporine treatment and requires the N-terminus of the protein. The N-terminus contains an ER leader sequence, putative nuclear localization signal, and is required for secretion. Deletion of the N-terminus resulted in mislocalization from the ER and suppression of HIV infection. Passive transfer experiments showed that secreted CypB did not impact HIV infection. Combined, these experiments show that intracellular CypB modulates a pathway of HIV nuclear import. Copyright © 2015 Elsevier Inc. All rights reserved.

  17. Field evaluation of an open and polyvalent universal HIV-1/SIVcpz/SIVgor quantitative RT-PCR assay for HIV-1 viral load monitoring in comparison to Abbott RealTime HIV-1 in Cameroon.

    Science.gov (United States)

    Guichet, Emilande; Aghokeng, Avelin; Eymard-Duvernay, Sabrina; Vidal, Nicole; Ayouba, Ahidjo; Mpoudi Ngole, Eitel; Delaporte, Eric; Ciaffi, Laura; Peeters, Martine

    2016-11-01

    With the increasing demand of HIV viral load (VL) tests in resource-limited countries (RLCs) there is a need for assays at affordable cost and able to quantify all known HIV-1 variants. VLs obtained with a recently developed open and polyvalent universal HIV-1/SIVcpz/SIVgor RT-qPCR were compared to Abbott RealTime HIV-1 assay in Cameroon. On 474 plasma samples, characterized by a wide range of VLs and a broad HIV-1 group M genetic diversity, 97.5% concordance was observed when using the lower detection limit of each assay. When using the threshold of 3.00 log 10 copies/mL, according to WHO guidelines to define virological failure (VF) in RLCs, the concordance was 94.7%, 360/474 versus 339/474 patients were identified with VF with the new assay and Abbott RealTime HIV-1, respectively. Higher VLs were measured with the new assay, +0.47 log 10 copies/mL (95% CI; 0.42-0.52) as shown with Bland-Altman analysis. Eleven samples from patients on VF with drug resistance were not detected by Abbott RealTime HIV-1 versus two only with the new assay. Overall, our study showed that the new assay can be easily implemented in a laboratory in RLCs with VL experience and showed good performance on a wide diversity of HIV-1 group M variants. Copyright © 2016 Elsevier B.V. All rights reserved.

  18. The global transmission network of HIV-1.

    Science.gov (United States)

    Wertheim, Joel O; Leigh Brown, Andrew J; Hepler, N Lance; Mehta, Sanjay R; Richman, Douglas D; Smith, Davey M; Kosakovsky Pond, Sergei L

    2014-01-15

    Human immunodeficiency virus type 1 (HIV-1) is pandemic, but its contemporary global transmission network has not been characterized. A better understanding of the properties and dynamics of this network is essential for surveillance, prevention, and eventual eradication of HIV. Here, we apply a simple and computationally efficient network-based approach to all publicly available HIV polymerase sequences in the global database, revealing a contemporary picture of the spread of HIV-1 within and between countries. This approach automatically recovered well-characterized transmission clusters and extended other clusters thought to be contained within a single country across international borders. In addition, previously undescribed transmission clusters were discovered. Together, these clusters represent all known modes of HIV transmission. The extent of international linkage revealed by our comprehensive approach demonstrates the need to consider the global diversity of HIV, even when describing local epidemics. Finally, the speed of this method allows for near-real-time surveillance of the pandemic's progression.

  19. Mutations in the Lactococcus lactis Ll.LtrB group II intron that retain mobility in vivo

    Directory of Open Access Journals (Sweden)

    D'Souza Lisa M

    2002-12-01

    Full Text Available Abstract Background Group II introns are mobile genetic elements that form conserved secondary and tertiary structures. In order to determine which of the conserved structural elements are required for mobility, a series of domain and sub-domain deletions were made in the Lactococcus lactis group II intron (Ll.LtrB and tested for mobility in a genetic assay. Point mutations in domains V and VI were also tested. Results The largest deletion that could be made without severely compromising mobility was 158 nucleotides in DIVb(1–2. This mutant had a mobility frequency comparable to the wild-type Ll.LtrB intron (ΔORF construct. Hence, all subsequent mutations were done in this mutant background. Deletion of DIIb reduced mobility to approximately 18% of wild-type, while another deletion in domain II (nts 404–459 was mobile to a minor extent. Only two deletions in DI and none in DIII were tolerated. Some mobility was also observed for a DIVa deletion mutant. Of the three point mutants at position G3 in DV, only G3A retained mobility. In DVI, deletion of the branch-point nucleotide abolished mobility, but the presence of any nucleotide at the branch-point position restored mobility to some extent. Conclusions The smallest intron capable of efficient retrohoming was 725 nucleotides, comprising the DIVb(1–2 and DII(iia,b deletions. The tertiary elements found to be nonessential for mobility were alpha, kappa and eta. In DV, only the G3A mutant was mobile. A branch-point residue is required for intron mobility.

  20. Evaluation of four rapid tests for diagnosis and differentiation of HIV-1 and HIV-2 infections in Guinea-Conakry, West Africa.

    Science.gov (United States)

    Chaillet, Pascale; Tayler-Smith, Katie; Zachariah, Rony; Duclos, Nanfack; Moctar, Diallo; Beelaert, Greet; Fransen, Katrien

    2010-09-01

    With both HIV-1 and HV-2 prevalent in Guinea-Conakry, accurate diagnosis and differentiation is crucial for treatment purposes. Thus, four rapid HIV tests were evaluated for their HIV-1 and HIV-2 diagnostic and discriminative capacity for use in Guinea-Conakry. These included SD Bioline HIV 1/2 3.0 (Standard Diagnostics Inc.), Genie II HIV1/HIV2 (Bio-Rad), First Response HIV Card Test 1-2.0 (PMC Medical) and Immunoflow HIV1-HIV2 (Core Diagnostics). Results were compared with gold standard tests (INNO-LIA HIV-I/II Score) and NEW LAV BLOT II (Bio-Rad). Four hundred and forty three sequential stored HIV-positive serum samples, of known HIV-type, were evaluated. Genie II HIV1/HIV2, Immunoflow HIV1-HIV2 and SD Bioline HIV 1/2 3.0 had 100% sensitivity (95% CI, 98.9-100%) while for First Response HIV Card Test 1-2.0 this was 99.5% (95% CI, 98.2%-99.9%). In terms of discriminatory capacity, Genie II HIV1/HIV2 identified 382/ 384(99.5%) HIV-1 samples, 49/ 52(95%) HIV-2 and 7/7(100%) HIV-positive untypable samples. Immunoflow HIV1-HIV2 identified 99% HIV-1, 67% HIV-2 and all HIV-positive untypable samples. First Response HIV Card Test 1-2.0 identified 94% HIV-1, 64% HIV-2 and 57% HIV-positive untypable samples. SD-Bioline HIV 1/2 3.0 was the worst overall performer identifying 65% HIV-1, 69% HIV-2 and all HIV-positive untypable samples. The use of SD Bioline HIV 1/2 3.0 (the current standard in Guinea-Conakry) as a discriminatory HIV test is poor and may be best replaced by Immunoflow HIV1-HIV2. Copyright 2010 Royal Society of Tropical Medicine and Hygiene. Published by Elsevier Ltd. All rights reserved.

  1. Epigenetic regulation of transcription and possible functions of mammalian short interspersed elements, SINEs.

    Science.gov (United States)

    Ichiyanagi, Kenji

    2013-01-01

    Short interspersed elements (SINEs) are a class of retrotransposons, which amplify their copy numbers in their host genomes by retrotransposition. More than a million copies of SINEs are present in a mammalian genome, constituting over 10% of the total genomic sequence. In contrast to the other two classes of retrotransposons, long interspersed elements (LINEs) and long terminal repeat (LTR) elements, SINEs are transcribed by RNA polymerase III. However, like LINEs and LTR elements, the SINE transcription is likely regulated by epigenetic mechanisms such as DNA methylation, at least for human Alu and mouse B1. Whereas SINEs and other transposable elements have long been thought as selfish or junk DNA, recent studies have revealed that they play functional roles at their genomic locations, for example, as distal enhancers, chromatin boundaries and binding sites of many transcription factors. These activities imply that SINE retrotransposition has shaped the regulatory network and chromatin landscape of their hosts. Whereas it is thought that the epigenetic mechanisms were originated as a host defense system against proliferation of parasitic elements, this review discusses a possibility that the same mechanisms are also used to regulate the SINE-derived functions.

  2. Interactions between the HIV-1 Unspliced mRNA and Host mRNA Decay Machineries

    Directory of Open Access Journals (Sweden)

    Daniela Toro-Ascuy

    2016-11-01

    Full Text Available The human immunodeficiency virus type-1 (HIV-1 unspliced transcript is used both as mRNA for the synthesis of structural proteins and as the packaged genome. Given the presence of retained introns and instability AU-rich sequences, this viral transcript is normally retained and degraded in the nucleus of host cells unless the viral protein REV is present. As such, the stability of the HIV-1 unspliced mRNA must be particularly controlled in the nucleus and the cytoplasm in order to ensure proper levels of this viral mRNA for translation and viral particle formation. During its journey, the HIV-1 unspliced mRNA assembles into highly specific messenger ribonucleoproteins (mRNPs containing many different host proteins, amongst which are well-known regulators of cytoplasmic mRNA decay pathways such as up-frameshift suppressor 1 homolog (UPF1, Staufen double-stranded RNA binding protein 1/2 (STAU1/2, or components of miRNA-induced silencing complex (miRISC and processing bodies (PBs. More recently, the HIV-1 unspliced mRNA was shown to contain N6-methyladenosine (m6A, allowing the recruitment of YTH N6-methyladenosine RNA binding protein 2 (YTHDF2, an m6A reader host protein involved in mRNA decay. Interestingly, these host proteins involved in mRNA decay were shown to play positive roles in viral gene expression and viral particle assembly, suggesting that HIV-1 interacts with mRNA decay components to successfully accomplish viral replication. This review summarizes the state of the art in terms of the interactions between HIV-1 unspliced mRNA and components of different host mRNA decay machineries.

  3. The regulated secretory pathway in CD4(+ T cells contributes to human immunodeficiency virus type-1 cell-to-cell spread at the virological synapse.

    Directory of Open Access Journals (Sweden)

    Clare Jolly

    2011-09-01

    Full Text Available Direct cell-cell spread of Human Immunodeficiency Virus type-1 (HIV-1 at the virological synapse (VS is an efficient mode of dissemination between CD4(+ T cells but the mechanisms by which HIV-1 proteins are directed towards intercellular contacts is unclear. We have used confocal microscopy and electron tomography coupled with functional virology and cell biology of primary CD4(+ T cells from normal individuals and patients with Chediak-Higashi Syndrome and report that the HIV-1 VS displays a regulated secretion phenotype that shares features with polarized secretion at the T cell immunological synapse (IS. Cell-cell contact at the VS re-orientates the microtubule organizing center (MTOC and organelles within the HIV-1-infected T cell towards the engaged target T cell, concomitant with polarization of viral proteins. Directed secretion of proteins at the T cell IS requires specialized organelles termed secretory lysosomes (SL and we show that the HIV-1 envelope glycoprotein (Env localizes with CTLA-4 and FasL in SL-related compartments and at the VS. Finally, CD4(+ T cells that are disabled for regulated secretion are less able to support productive cell-to-cell HIV-1 spread. We propose that HIV-1 hijacks the regulated secretory pathway of CD4(+ T cells to enhance its dissemination.

  4. SP-D impedes transfer of HIV-1 from multi-layered vaginal epithelium with a distinct gene signature

    Directory of Open Access Journals (Sweden)

    Hrishikesh Pandit

    2017-12-01

    Full Text Available Surfactant Protein (SP D is a member of the collectin family of soluble pattern recognition receptors. We have previously shown that a recombinant fragment of SP-D (rhSP-D inhibits gp120-CD4 interaction and HIV-1 entry in target cells. To potentiate its prophylactic use as a vaginal microbicide, we determined ex vivo efficacy using organotypic human vaginal-ectocervical epithelia (VEC-100 that closely resemble the native tissues of origin. VEC-100, stratified human vaginal-ectocervical tissues grown on membrane inserts were treated with rhSP-D followed by a challenge with HIV-1 to assess the transfer of HIV-1 through the VEC-100 tissues to PBMCs in the basal submucosal compartment. Treated VEC tissues were subjected to mRNA Illumina microarray analysis. Levels of transcripts encoding for immune mediators, adhesion and tight junction proteins were also evaluated. Effect of rhSP-D on viability, NFκB activation, cytokine secretion and bacterial colonization of cervical vaginal epithelial cells was determined. rhSP-D significantly inhibited HIV-1 transfer from the multi-layered epithelial tissues to the basal PBMCs as compared to HIV-1 alone. Global gene expression profile of HIV-1 challenged VEC-100 tissues revealed differential regulation of genes and pathways majorly involved in inflammation, cell survival and transcription factors. Levels of Guanylate-binding proteins (GBPs and interferon-inducible proteins were significantly upregulated suggesting an interferon host defense response. rhSP-D showed an inhibition in the levels of GBPs and rescued the cell adhesion molecules such as Claudin 2, 3, 4, 5 and Occludin, known to be down regulated by HIV-1 in primary vaginal cells. Importantly, rhSP-D conditioned VEC tissue supernatants did not enhance susceptibility of target cells to HIV-1. rhSP-D treated vaginal epithelial cells did not show any significant alteration in viability, NFκB activation and levels of immune mediators like IL-1RA, Elafin

  5. HIV-1 proteins dysregulate motivational processes and dopamine circuitry.

    Science.gov (United States)

    Bertrand, Sarah J; Mactutus, Charles F; Harrod, Steven B; Moran, Landhing M; Booze, Rosemarie M

    2018-05-18

    Motivational alterations, such as apathy, in HIV-1+ individuals are associated with decreased performance on tasks involving frontal-subcortical circuitry. We used the HIV-1 transgenic (Tg) rat to assess effect of long-term HIV-1 protein exposure on motivated behavior using sucrose (1-30%, w/v) and cocaine (0.01-1.0 mg/kg/infusion) maintained responding with fixed-ratio (FR) and progressive-ratio (PR) schedules of reinforcement. For sucrose-reinforced responding, HIV-1 Tg rats displayed no change in EC 50 relative to controls, suggesting no change in sucrose reinforcement but had a downward shifted concentration-response curves, suggesting a decrease in response vigor. Cocaine-maintained responding was attenuated in HIV-1 Tg rats (FR1 0.33 mg/kg/infusion and PR 1.0 mg/kg/infusion). Dose-response tests (PR) revealed that HIV-1 Tg animals responded significantly less than F344 control rats and failed to earn significantly more infusions of cocaine as the unit dose increased. When choosing between cocaine and sucrose, control rats initially chose sucrose but with time shifted to a cocaine preference. In contrast, HIV-1 disrupted choice behaviors. DAT function was altered in the striatum of HIV-1 Tg rats; however, prior cocaine self-administration produced a unique effect on dopamine homeostasis in the HIV-1 Tg striatum. These findings of altered goal directed behaviors may determine neurobiological mechanisms of apathy in HIV-1+ patients.

  6. Profile of HIV-1 RNA viral load among HIV-TB co-infected patients in ...

    African Journals Online (AJOL)

    Profile of HIV-1 RNA viral load among HIV-TB co-infected patients in a tertiary health facility in Maiduguri, Northeastern Nigeria. ... This study aims to estimate the HIV-1 RNA viral load and impact of anti TB therapy (ATT) ... HOW TO USE AJOL.

  7. Tailored HIV-1 vectors for genetic modification of primary human dendritic cells and monocytes.

    Science.gov (United States)

    Durand, Stéphanie; Nguyen, Xuan-Nhi; Turpin, Jocelyn; Cordeil, Stephanie; Nazaret, Nicolas; Croze, Séverine; Mahieux, Renaud; Lachuer, Joël; Legras-Lachuer, Catherine; Cimarelli, Andrea

    2013-01-01

    Monocyte-derived dendritic cells (MDDCs) play a key role in the regulation of the immune system and are the target of numerous gene therapy applications. The genetic modification of MDDCs is possible with human immunodeficiency virus type 1 (HIV-1)-derived lentiviral vectors (LVs) but requires high viral doses to bypass their natural resistance to viral infection, and this in turn affects their physiological properties. To date, a single viral protein is able to counter this restrictive phenotype, Vpx, a protein derived from members of the HIV-2/simian immunodeficiency virus SM lineage that counters at least two restriction factors present in myeloid cells. By tagging Vpx with a short heterologous membrane-targeting domain, we have obtained HIV-1 LVs incorporating high levels of this protein (HIV-1-Src-Vpx). These vectors efficiently transduce differentiated MDDCs and monocytes either as previously purified populations or as populations within unsorted peripheral blood mononuclear cells (PBMCs). In addition, these vectors can be efficiently pseudotyped with receptor-specific envelopes, further restricting their cellular tropism almost uniquely to MDDCs. Compared to conventional HIV-1 LVs, these novel vectors allow for an efficient genetic modification of MDDCs and, more importantly, do not cause their maturation or affect their survival, which are unwanted side effects of the transduction process. This study describes HIV-1-Src-Vpx LVs as a novel potent tool for the genetic modification of differentiated MDDCs and of circulating monocyte precursors with strong potential for a wide range of gene therapy applications.

  8. Sieve analysis in HIV-1 vaccine efficacy trials.

    Science.gov (United States)

    Edlefsen, Paul T; Gilbert, Peter B; Rolland, Morgane

    2013-09-01

    The genetic characterization of HIV-1 breakthrough infections in vaccine and placebo recipients offers new ways to assess vaccine efficacy trials. Statistical and sequence analysis methods provide opportunities to mine the mechanisms behind the effect of an HIV vaccine. The release of results from two HIV-1 vaccine efficacy trials, Step/HVTN-502 (HIV Vaccine Trials Network-502) and RV144, led to numerous studies in the last 5 years, including efforts to sequence HIV-1 breakthrough infections and compare viral characteristics between the vaccine and placebo groups. Novel genetic and statistical analysis methods uncovered features that distinguished founder viruses isolated from vaccinees from those isolated from placebo recipients, and identified HIV-1 genetic targets of vaccine-induced immune responses. Studies of HIV-1 breakthrough infections in vaccine efficacy trials can provide an independent confirmation to correlates of risk studies, as they take advantage of vaccine/placebo comparisons, whereas correlates of risk analyses are limited to vaccine recipients. Through the identification of viral determinants impacted by vaccine-mediated host immune responses, sieve analyses can shed light on potential mechanisms of vaccine protection.

  9. Constitutively Active MAVS Inhibits HIV-1 Replication via Type I Interferon Secretion and Induction of HIV-1 Restriction Factors.

    Directory of Open Access Journals (Sweden)

    Sachin Gupta

    Full Text Available Type I interferon is known to inhibit HIV-1 replication through the induction of interferon stimulated genes (ISG, including a number of HIV-1 restriction factors. To better understand interferon-mediated HIV-1 restriction, we constructed a constitutively active form of the RIG-I adapter protein MAVS. Constitutive MAVS was generated by fusion of full length MAVS to a truncated form of the Epstein Barr virus protein LMP1 (ΔLMP1. Supernatant from ΔLMP1-MAVS-transfected 293T cells contained high levels of type I interferons and inhibited HIV replication in both TZM-bl and primary human CD4+ T cells. Supernatant from ΔLMP1-MAVS-transfected 293T cells also inhibited replication of VSV-G pseudotyped single cycle SIV in TZM-bl cells, suggesting restriction was post-entry and common to both HIV and SIV. Gene array analysis of ΔLMP1-MAVS-transfected 293T cells and trans-activated CD4+ T cells showed significant upregulation of ISG, including previously characterized HIV restriction factors Viperin, Tetherin, MxB, and ISG56. Interferon blockade studies implicated interferon-beta in this response. In addition to direct viral inhibition, ΔLMP1-MAVS markedly enhanced secretion of IFN-β and IL-12p70 by dendritic cells and the activation and maturation of dendritic cells. Based on this immunostimulatory activity, an adenoviral vector (Ad5 expressing ΔLMP1-MAVS was tested as a molecular adjuvant in an HIV vaccine mouse model. Ad5-Gag antigen combined with Ad5-ΔLMP1-MAVS enhanced control of vaccinia-gag replication in a mouse challenge model, with 4/5 animals showing undetectable virus following challenge. Overall, ΔLMP1-MAVS is a promising reagent to inhibit HIV-1 replication in infected tissues and enhance vaccine-mediated immune responses, while avoiding toxicity associated with systemic type I interferon administration.

  10. Frequency and site mapping of HIV-1/SIVcpz, HIV- 2/SIVsmm and ...

    African Journals Online (AJOL)

    out to analyze the effects of various restriction enzymes on the HIV genome. A computer simulated model using Web cutter Version 2.0, and cytogenetic analysis. 339 restriction enzymes from Promega database, 10 HIV-1/SIVcpz genes, 10 HIV-2/SIVsmm genes and 10 other SIV genes. Gene sequences were fed into Web ...

  11. Salicylic acid inhibits UV- and Cis-Pt-induced human immunodeficiency virus expression

    International Nuclear Information System (INIS)

    Woloschak, G.E.; Panozzo, J.; Libertin, C.R.; Schreck, S.; South Carolina Univ., Columbia, SC

    1994-01-01

    Previous studies have shown that exposure of HeLa cells stably transfected with a human immunodeficiency virus-long terminal repeat-chloramphenicol acetyl transferase (HIV-LTR-CAT) construct to UV light-induced expression from the HIV LTR. By culturing the cells with salicylic acid we demonstrated dose-dependent repression of this induced HIV expression. Repression was evident if salicylic acid was administered 2 h before, at the same time as, or up to 6 h after exposure to the DNA-damaging agent. The kinetics were similar for UV- and for cis-Pt-induced HIV expression, and induction was dependent on the UV dose or cis-Pt concentration added to the culture. These results suggest a role for the prostaglandins or the cyclooxygenase pathway or both in HIV induction mediated by DNA-damaging agents

  12. Dual-mixed HIV-1 coreceptor tropism and HIV-associated neurocognitive deficits.

    Science.gov (United States)

    Morris, Sheldon R; Woods, Steven Paul; Deutsch, Reena; Little, Susan J; Wagner, Gabriel; Morgan, Erin E; Heaton, Robert K; Letendre, Scott L; Grant, Igor; Smith, Davey M

    2013-10-01

    HIV coreceptor usage of CXCR4 (X4) is associated with decreased CD4+ T-cell counts and accelerated disease progression, but the role of X4 tropism in HIV-associated neurocognitive disorders (HAND) has not previously been described. This longitudinal study evaluated data on 197 visits from 72 recently HIV-infected persons who had undergone up to four sequential neurocognitive assessments over a median of 160 days (IQR, 138–192). Phenotypic tropism testing (Trofile ES, Monogram, Biosciences) was performed on stored blood samples. Multivariable mixed model repeated measures regression was used to determine the association between HAND and dual-mixed (DM) viral tropism, estimated duration of infection (EDI), HIV RNA, CD4 count, and problematic methamphetamine use. Six subjects (8.3 %) had DM at their first neurocognitive assessment and four converted to DM in subsequent sampling (for total of 10 DM) at a median EDI of 10.1 months (IQR, 7.2–12.2). There were 44 (61.1 %) subjects who demonstrated HAND on at least one study visit. HAND was associated with DM tropism (odds ratio, 4.4; 95 % CI, 0.9–20.5) and shorter EDI (odds ratio 1.1 per month earlier; 95 % CI, 1.0–1.2). This study found that recency of HIV-1 infection and the development of DM tropism may be associated with HAND in the relatively early stage of infection. Together, these data suggest that viral interaction with cellular receptors may play an important role in the early manifestation of HAND.

  13. HIV/HTLV-1 co-infection

    African Journals Online (AJOL)

    result of a lymphoproliferative disorder. In the context of HIV co-infection, lympho- cytosis has been described during early sero- conversion associated with CMV, as well as in HIV/HTLV-1 co-infection where CD4+ lymphocytosis can be caused by both a reactive or clonal expansion. Consequently, patients with untreated ...

  14. The histone deacetylase inhibitor vorinostat (SAHA) increases the susceptibility of uninfected CD4+ T cells to HIV by increasing the kinetics and efficiency of postentry viral events.

    Science.gov (United States)

    Lucera, Mark B; Tilton, Carisa A; Mao, Hongxia; Dobrowolski, Curtis; Tabler, Caroline O; Haqqani, Aiman A; Karn, Jonathan; Tilton, John C

    2014-09-01

    Latently infected cells remain a primary barrier to eradication of HIV-1. Over the past decade, a better understanding of the molecular mechanisms by which latency is established and maintained has led to the discovery of a number of compounds that selectively reactivate latent proviruses without inducing polyclonal T cell activation. Recently, the histone deacetylase (HDAC) inhibitor vorinostat has been demonstrated to induce HIV transcription from latently infected cells when administered to patients. While vorinostat will be given in the context of antiretroviral therapy (ART), infection of new cells by induced virus remains a clinical concern. Here, we demonstrate that vorinostat significantly increases the susceptibility of CD4(+) T cells to infection by HIV in a dose- and time-dependent manner that is independent of receptor and coreceptor usage. Vorinostat does not enhance viral fusion with cells but rather enhances the kinetics and efficiency of postentry viral events, including reverse transcription, nuclear import, and integration, and enhances viral production in a spreading-infection assay. Selective inhibition of the cytoplasmic class IIb HDAC6 with tubacin recapitulated the effect of vorinostat. These findings reveal a previously unknown cytoplasmic effect of HDAC inhibitors promoting productive infection of CD4(+) T cells that is distinct from their well-characterized effects on nuclear histone acetylation and long-terminal-repeat (LTR) transcription. Our results indicate that careful monitoring of patients and ART intensification are warranted during vorinostat treatment and indicate that HDAC inhibitors that selectively target nuclear class I HDACs could reactivate latent HIV without increasing the susceptibility of uninfected cells to HIV. HDAC inhibitors, particularly vorinostat, are currently being investigated clinically as part of a "shock-and-kill" strategy to purge latent reservoirs of HIV. We demonstrate here that vorinostat increases the

  15. Human T-lymphotropic virus type 1 Tax protein complexes with P-TEFb and competes for Brd4 and 7SK snRNP/HEXIM1 binding.

    Science.gov (United States)

    Cho, Won-Kyung; Jang, Moon Kyoo; Huang, Keven; Pise-Masison, Cynthia A; Brady, John N

    2010-12-01

    Positive transcription elongation factor b (P-TEFb) plays an important role in stimulating RNA polymerase II elongation for viral and cellular gene expression. P-TEFb is found in cells in either an active, low-molecular-weight (LMW) form or an inactive, high-molecular-weight (HMW) form. We report here that human T-lymphotropic virus type 1 (HTLV-1) Tax interacts with the cyclin T1 subunit of P-TEFb, forming a distinct Tax/P-TEFb LMW complex. We demonstrate that Tax can play a role in regulating the amount of HMW complex present in the cell by decreasing the binding of 7SK snRNP/HEXIM1 to P-TEFb. This is seen both in vitro using purified Tax protein and in vivo in cells transduced with Tax expression constructs. Further, we find that a peptide of cyclin T1 spanning the Tax binding domain inhibits the ability of Tax to disrupt HMW P-TEFb complexes. These results suggest that the direct interaction of Tax with cyclin T1 can dissociate P-TEFb from the P-TEFb/7SK snRNP/HEXIM1 complex for activation of the viral long terminal repeat (LTR). We also show that Tax competes with Brd4 for P-TEFb binding. Chromatin immunoprecipitation (ChIP) assays demonstrated that Brd4 and P-TEFb are associated with the basal HTLV-1 LTR, while Tax and P-TEFb are associated with the activated template. Furthermore, the knockdown of Brd4 by small interfering RNA (siRNA) activates the HTLV-1 LTR promoter, which results in an increase in viral expression and production. Our studies have identified Tax as a regulator of P-TEFb that is capable of affecting the balance between its association with the large inactive complex and the small active complex.

  16. The export receptor Crm1 forms a dimer to promote nuclear export of HIV RNA.

    Science.gov (United States)

    Booth, David S; Cheng, Yifan; Frankel, Alan D

    2014-12-08

    The HIV Rev protein routes viral RNAs containing the Rev Response Element (RRE) through the Crm1 nuclear export pathway to the cytoplasm where viral proteins are expressed and genomic RNA is delivered to assembling virions. The RRE assembles a Rev oligomer that displays nuclear export sequences (NESs) for recognition by the Crm1-Ran(GTP) nuclear receptor complex. Here we provide the first view of an assembled HIV-host nuclear export complex using single-particle electron microscopy. Unexpectedly, Crm1 forms a dimer with an extensive interface that enhances association with Rev-RRE and poises NES binding sites to interact with a Rev oligomer. The interface between Crm1 monomers explains differences between Crm1 orthologs that alter nuclear export and determine cellular tropism for viral replication. The arrangement of the export complex identifies a novel binding surface to possibly target an HIV inhibitor and may point to a broader role for Crm1 dimerization in regulating host gene expression.

  17. Correlates of HIV-1 genital shedding in Tanzanian women.

    Directory of Open Access Journals (Sweden)

    Clare Tanton

    2011-03-01

    Full Text Available Understanding the correlates of HIV shedding is important to inform strategies to reduce HIV infectiousness. We examined correlates of genital HIV-1 RNA in women who were seropositive for both herpes simplex virus (HSV-2 and HIV-1 and who were enrolled in a randomised controlled trial of HSV suppressive therapy (aciclovir 400 mg b.i.d vs. placebo in Tanzania.Samples, including a cervico-vaginal lavage, were collected and tested for genital HIV-1 and HSV and reproductive tract infections (RTIs at randomisation and 6, 12 and 24 months follow-up. Data from all women at randomisation and women in the placebo arm during follow-up were analysed using generalised estimating equations to determine the correlates of cervico-vaginal HIV-1 RNA detection and load.Cervico-vaginal HIV-1 RNA was detected at 52.0% of 971 visits among 482 women, and was independently associated with plasma viral load, presence of genital ulcers, pregnancy, bloody cervical or vaginal discharge, abnormal vaginal discharge, cervical ectopy, Neisseria gonorrhoeae, Chlamydia trachomatis, Trichomonas vaginalis, an intermediate bacterial vaginosis score and HSV DNA detection. Similar factors were associated with genital HIV-1 RNA load.RTIs were associated with increased presence and quantity of genital HIV-1 RNA in this population. These results highlight the importance of integrating effective RTI treatment into HIV care services.

  18. Frequent intra-subtype recombination among HIV-1 circulating in Tanzania.

    Directory of Open Access Journals (Sweden)

    Ireen E Kiwelu

    Full Text Available The study estimated the prevalence of HIV-1 intra-subtype recombinant variants among female bar and hotel workers in Tanzania. While intra-subtype recombination occurs in HIV-1, it is generally underestimated. HIV-1 env gp120 V1-C5 quasispecies from 45 subjects were generated by single-genome amplification and sequencing (median (IQR of 38 (28-50 sequences per subject. Recombination analysis was performed using seven methods implemented within the recombination detection program version 3, RDP3. HIV-1 sequences were considered recombinant if recombination signals were detected by at least three methods with p-values of ≤0.05 after Bonferroni correction for multiple comparisons. HIV-1 in 38 (84% subjects showed evidence for intra-subtype recombination including 22 with HIV-1 subtype A1, 13 with HIV-1 subtype C, and 3 with HIV-1 subtype D. The distribution of intra-patient recombination breakpoints suggested ongoing recombination and showed selective enrichment of recombinant variants in 23 (60% subjects. The number of subjects with evidence of intra-subtype recombination increased from 29 (69% to 36 (82% over one year of follow-up, although the increase did not reach statistical significance. Adjustment for intra-subtype recombination is important for the analysis of multiplicity of HIV infection. This is the first report of high prevalence of intra-subtype recombination in the HIV/AIDS epidemic in Tanzania, a region where multiple HIV-1 subtypes co-circulate. HIV-1 intra-subtype recombination increases viral diversity and presents additional challenges for HIV-1 vaccine design.

  19. Regional gene expression of LOX-1, VCAM-1, and ICAM-1 in aorta of HIV-1 transgenic rats.

    Directory of Open Access Journals (Sweden)

    Anne Mette Fisker Hag

    Full Text Available BACKGROUND: Increased prevalence of atherosclerotic cardiovascular disease in HIV-infected patients has been observed. The cause of this accelerated atherosclerosis is a matter of controversy. As clinical studies are complicated by a multiplicity of risk-factors and a low incidence of hard endpoints, studies in animal models could be attractive alternatives. METHODOLOGY/PRINCIPAL FINDINGS: We evaluated gene expression of lectin-like oxidized-low-density-lipoprotein receptor-1 (LOX-1, vascular cell adhesion molecule-1 (VCAM-1, and intercellular adhesion molecule-1 (ICAM-1 in HIV-1 transgenic (HIV-1Tg rats; these genes are all thought to play important roles in early atherogenesis. Furthermore, the plasma level of sICAM-1 was measured. We found that gene expressions of LOX-1 and VCAM-1 were higher in the aortic arch of HIV-1Tg rats compared to controls. Also, the level of sICAM-1 was elevated in the HIV-1Tg rats compared to controls, but the ICAM-1 gene expression profile did not show any differences between the groups. CONCLUSIONS/SIGNIFICANCE: HIV-1Tg rats have gene expression patterns indicating endothelial dysfunction and accelerated atherosclerosis in aorta, suggesting that HIV-infection per se may cause atherosclerosis. This transgenic rat model may be a very promising model for further studies of the pathophysiology behind HIV-associated cardiovascular disease.

  20. HIV epidemiology. The early spread and epidemic ignition of HIV-1 in human populations.

    Science.gov (United States)

    Faria, Nuno R; Rambaut, Andrew; Suchard, Marc A; Baele, Guy; Bedford, Trevor; Ward, Melissa J; Tatem, Andrew J; Sousa, João D; Arinaminpathy, Nimalan; Pépin, Jacques; Posada, David; Peeters, Martine; Pybus, Oliver G; Lemey, Philippe

    2014-10-03

    Thirty years after the discovery of HIV-1, the early transmission, dissemination, and establishment of the virus in human populations remain unclear. Using statistical approaches applied to HIV-1 sequence data from central Africa, we show that from the 1920s Kinshasa (in what is now the Democratic Republic of Congo) was the focus of early transmission and the source of pre-1960 pandemic viruses elsewhere. Location and dating estimates were validated using the earliest HIV-1 archival sample, also from Kinshasa. The epidemic histories of HIV-1 group M and nonpandemic group O were similar until ~1960, after which group M underwent an epidemiological transition and outpaced regional population growth. Our results reconstruct the early dynamics of HIV-1 and emphasize the role of social changes and transport networks in the establishment of this virus in human populations. Copyright © 2014, American Association for the Advancement of Science.

  1. HIV-1 protease inhibitory substances from Cassia garrettiana

    Directory of Open Access Journals (Sweden)

    Jindaporn Puripattanvong

    2007-01-01

    Full Text Available Cassia garrettiana Craib, a Thai medicinal plant locally known as Samae-sarn, was investigated for its active constituents against HIV-1 protease (HIV-1 PR. Bioassay-guided fractionation of the heart woodof this plant led to the isolation of a stilbene derivative (1, piceatannol and an anthraquinone derivative (2, chrysophanol. Piceatannol exhibited appreciable inhibitory effect against HIV-1 PR with an IC50 value of25.4 μg/ml, whereas that of chrysophanol was 73.5 μg/ml. In addition, other two stilbenoids together with three anthraquinone derivatives were also investigated for their anti-HIV-1 PR activities. The resultindicated that resveratrol possessed anti-HIV-1 PR activity with an IC50 value of 85.0 μg/ml, whereas other stilbenoid (oxyresveratrol and anthraquinone derivatives (emodin, aloe-emodin, rhein were inactive (IC50 > 100 μg/ml.

  2. The Epidemiology of HIV-1 Transmitted Drug Resistance

    NARCIS (Netherlands)

    D. Frentz (Dineke)

    2012-01-01

    textabstractThe human immunodeficiency virus (HIV) was first discovered in 1983. In 2009, it was estimated that 33.3 (31.4 -35.3) million individuals are infected with HIV worldwide. In that year 1.8 (1.6-2.1) million people died from HIV. Although the virus continues to spread, the number of new

  3. Increased Risk of Female HIV-1 Acquisition Throughout Pregnancy and Postpartum: A Prospective Per-coital Act Analysis Among Women with HIV-1 Infected Partners.

    Science.gov (United States)

    Thomson, Kerry A; Hughes, James; Baeten, Jared M; John-Stewart, Grace; Celum, Connie; Cohen, Craig R; Ngure, Kenneth; Kiarie, James; Mugo, Nelly; Heffron, Renee

    2018-03-05

    Understanding the absolute and relative risk of HIV-1 acquisition during pregnancy and postpartum can inform HIV-1 prevention strategies for women. We used a complementary log-log model and data from 2,751 HIV-1 serodiscordant couples to compare the probability of women's HIV-1 acquisition risk per sex act during early pregnancy, late pregnancy, postpartum, and non-pregnant periods. At total of 686 pregnancies were identified and 82 incident HIV-1 infections occurred. After adjustment for condom use, age, PrEP use, and HIV-1 viral load, the per act probability of HIV-1 acquisition was higher in late pregnancy (aRR 2.82, p=0.01) and postpartum (aRR 3.97, p=0.01) compared to non-pregnant periods. The HIV-1 acquisition probability per condomless sex act for a 25 year old woman not taking PrEP with an HIV-1 infected male partner with viral load of 10,000 copies/ml was 0.0011 (95% CI: 0.005, 0.0019), 0.0022 (95% CI: 0.0004, 0.0093), 0.0030 (95% CI: 0.0007, 0.0108), and 0.0042 (95% CI: 0.0007, 0.0177) in the non-pregnant, early pregnant, late pregnant, and postpartum periods, respectively. The HIV-1 acquisition probability per condomless sex act steadily increased through pregnancy and was highest during the postpartum period, suggesting that biological changes during pregnancy and postpartum increase female HIV-1 susceptibility.

  4. HIV/AIDS testing at ports of entry in China.

    Science.gov (United States)

    Lai, Dejian; Hwang, Lu-Yu; Beasley, R Palmer

    2011-05-01

    In 2007 the Chinese government issued regulations requiring HIV/AIDS testing for Chinese citizens returning at ports of entry if they had resided outside China for 1 year or longer. Three years after publication and partial implementation of the regulations, the Chinese government decided to eliminate compulsory HIV/AIDS testing of returning Chinese. We examine the history of China's HIV/AIDS testing regulations on entry-exit populations, showing how China has gradually altered its policy. As of December 2010, the policy of compulsory HIV/AIDS testing of returning Chinese has been abandoned; however, the regulations still compel HIV/AIDS testing for other groups inside China. Our review sheds new light on the dynamics of regulatory changes in the last 3 years. The Chinese experience that we observed may provide useful insights for policymakers in other parts of the world.

  5. The Depsipeptide Romidepsin Reverses HIV-1 Latency In Vivo.

    Directory of Open Access Journals (Sweden)

    Ole S Søgaard

    2015-09-01

    Full Text Available Pharmacologically-induced activation of replication competent proviruses from latency in the presence of antiretroviral treatment (ART has been proposed as a step towards curing HIV-1 infection. However, until now, approaches to reverse HIV-1 latency in humans have yielded mixed results. Here, we report a proof-of-concept phase Ib/IIa trial where 6 aviremic HIV-1 infected adults received intravenous 5 mg/m2 romidepsin (Celgene once weekly for 3 weeks while maintaining ART. Lymphocyte histone H3 acetylation, a cellular measure of the pharmacodynamic response to romidepsin, increased rapidly (maximum fold range: 3.7–7.7 relative to baseline within the first hours following each romidepsin administration. Concurrently, HIV-1 transcription quantified as copies of cell-associated un-spliced HIV-1 RNA increased significantly from baseline during treatment (range of fold-increase: 2.4–5.0; p = 0.03. Plasma HIV-1 RNA increased from <20 copies/mL at baseline to readily quantifiable levels at multiple post-infusion time-points in 5 of 6 patients (range 46–103 copies/mL following the second infusion, p = 0.04. Importantly, romidepsin did not decrease the number of HIV-specific T cells or inhibit T cell cytokine production. Adverse events (all grade 1–2 were consistent with the known side effects of romidepsin. In conclusion, romidepsin safely induced HIV-1 transcription resulting in plasma HIV-1 RNA that was readily detected with standard commercial assays demonstrating that significant reversal of HIV-1 latency in vivo is possible without blunting T cell-mediated immune responses. These finding have major implications for future trials aiming to eradicate the HIV-1 reservoir.clinicaltrials.gov NTC02092116.

  6. Clustering patterns of cytotoxic T-lymphocyte epitopes in human immunodeficiency virus type 1 (HIV-1) proteins reveal imprints of immune evasion on HIV-1 global variation

    DEFF Research Database (Denmark)

    Yusim, K.; Kesmir, Can; Gaschen, B.

    2002-01-01

    The human cytotoxic T-lymphocyte (CTL) response to human immunodeficiency virus type 1 (HIV-1) has been intensely studied, and hundreds of CTL epitopes have been experimentally defined, published, and compiled in the HIV Molecular Immunology Database. Maps of CTL epitopes on HIV-1 protein sequenc...

  7. Minocycline attenuates HIV-1 infection and suppresses chronic immune activation in humanized NOD/LtsZ-scidIL-2Rγnull mice

    Science.gov (United States)

    Singh, Maneesh; Singh, Pratibha; Vaira, Dolores; Amand, Mathieu; Rahmouni, Souad; Moutschen, Michel

    2014-01-01

    More than a quarter of a century of research has established chronic immune activation and dysfunctional T cells as central features of chronic HIV infection and subsequent immunodeficiency. Consequently, the search for a new immunomodulatory therapy that could reduce immune activation and improve T-cell function has been increased. However, the lack of small animal models for in vivo HIV study has hampered progress. In the current study, we have investigated a model of cord blood haematopoietic progenitor cells (CB-HPCs) -transplanted humanized NOD/LtsZ-scidIL-2Rγnull mice in which progression of HIV infection is associated with widespread chronic immune activation and inflammation. Indeed, HIV infection in humanized NSG mice caused up-regulation of several T-cell immune activation markers such as CD38, HLA-DR, CD69 and co-receptor CCR5. T-cell exhaustion markers PD-1 and CTLA-4 were found to be significantly up-regulated on T cells. Moreover, increased plasmatic levels of lipopolysaccharide, sCD14 and interleukin-10 were also observed in infected mice. Treatment with minocycline resulted in a significant decrease of expression of cellular and plasma immune activation markers, inhibition of HIV replication and improved T-cell counts in HIV-infected humanized NSG mice. The study demonstrates that minocycline could be an effective, low-cost adjunctive treatment to regulate chronic immune activation and replication of HIV. PMID:24409837

  8. HIV-1 impairs human retinal pigment epithelial barrier function: possible association with the pathogenesis of HIV-associated retinopathy.

    Science.gov (United States)

    Tan, Suiyi; Duan, Heng; Xun, Tianrong; Ci, Wei; Qiu, Jiayin; Yu, Fei; Zhao, Xuyan; Wu, Linxuan; Li, Lin; Lu, Lu; Jiang, Shibo; Liu, Shuwen

    2014-07-01

    The breakdown of human retinal pigment epithelial (HRPE) barrier is considered as the etiology of retinopathy, which affects the quality of life of HIV/AIDS patients. Here we demonstrate that HIV-1 could directly impair HRPE barrier function, which leads to the translocation of HIV-1 and bacteria. HRPE cells (D407) were grown to form polarized, confluent monolayers and treated with different HIV-1 infectious clones. A significant increase of monolayer permeability, as measured by trans-epithelial electrical resistance (TEER) and apical-basolateral movements of sodium fluorescein, was observed. Disrupted tightness of HRPE barrier was associated with the downregulation of several tight junction proteins in D407 cells, including ZO-1, Occludin, Claudin-1, Claudin-2, Claudin-3, Claudin-4, and Claudin-5, after exposure to HIV-1, without affecting the viability of cells. HIV-1 gp120 was shown to participate in the alteration of barrier properties, as evidenced by decreased TEER and weakened expression of tight junction proteins in D407 monolayers after exposure to pseudotyped HIV-1, UV-inactivated HIV-1, and free gp120, but not to an envelope (Env)-defective mutant of HIV. Furthermore, exposure to HIV-1 particles could induce the release of pro-inflammatory cytokines in D407, including IL-6 and MCP-1, both of which downregulated the expression of ZO-1 in the HRPE barrier. Disrupted HRPE monolayer allowed translocation of HIV-1 and bacteria across the epithelium. Overall, these findings suggest that HIV-1 may exploit its Env glycoprotein to induce an inflammatory state in HRPE cells, which could result in impairment of HRPE monolayer integrity, allowing virus and bacteria existing in ocular fluids to cross the epithelium and penetrate the HRPE barrier. Our study highlights the role of HIV-1 in the pathogenesis of HIV/AIDS-related retinopathy and suggests potential therapeutic targets for this ocular complication.

  9. Trends of HIV-1, HIV-2 and dual infection in women attending outpatient clinics in Senegal, 1990–2009

    Science.gov (United States)

    Heitzinger, K; Sow, P S; Badiane, N M Dia; Gottlieb, G S; N’Doye, I; Toure, M; Kiviat, N B; Hawes, S E

    2013-01-01

    Summary We assessed trends in the relative prevalences of HIV-1, HIV-2 and dual HIV-1/HIV-2 infection in 10,321 women attending outpatient clinics in Senegal between 1990 and 2009. The relative prevalence of HIV-1 (defined as the proportion of seropositive subjects having HIV-1) rose sharply from 38% in 1990 until 1993 (P Senegal. From 1993 to 2009, the relative prevalence of HIV-1 increased at a slower rate, while the relative prevalences of HIV-2 and dual infection decreased. These results confirm trends in HIV prevalence observed in other West African populations and provide a critical update on HIV transmission risk among women in Senegal. PMID:23104745

  10. Rotavirus 2/6 Viruslike Particles Administered Intranasally with Cholera Toxin, Escherichia coli Heat-Labile Toxin (LT), and LT-R192G Induce Protection from Rotavirus Challenge

    OpenAIRE

    O’Neal, Christine M.; Clements, John D.; Estes, Mary K.; Conner, Margaret E.

    1998-01-01

    We have shown that rotavirus 2/6 viruslike particles composed of proteins VP2 and VP6 (2/6-VLPs) administered to mice intranasally with cholera toxin (CT) induced protection from rotavirus challenge, as measured by virus shedding. Since it is unclear if CT will be approved for human use, we evaluated the adjuvanticity of Escherichia coli heat-labile toxin (LT) and LT-R192G. Mice were inoculated intranasally with 10 μg of 2/6-VLPs combined with CT, LT, or LT-R192G. All three adjuvants induced ...

  11. Structure of HIV-1 protease determined by neutron crystallography

    International Nuclear Information System (INIS)

    Adachi, Motoyasu; Kuroki, Ryota

    2009-01-01

    HIV-1 protease is an aspartic protease, and plays an essential role in replication of HIV. To develop HIV-1 protease inhibitors through structure-based drug design, it is necessary to understand the catalytic mechanism and inhibitor recognition of HIV-1 protease. We have determined the crystal structure of HIV-1 protease in complex with KNI-272 to 1.9 A resolution by neutron crystallography in combination with 1.4 A resolution X-ray diffraction data. The results show that the carbonyl group of hydroxymethylcarbonyl (HMC) in KNI-272 forms a hydrogen bonding interaction with protonated Asp 25 and the hydrogen atom from the hydroxyl group of HMC forms a hydrogen bonding interaction with the deprotonated Asp125. This is the first neutron report for HIV-1/inhibitor complex and shows directly the locations of key hydrogen atoms in catalysis and in the binding of a transition-state analog. The results confirm key aspect of the presumed catalytic mechanism of HIV-1 protease and will aid in the further development of protease inhibitors. (author)

  12. The enzymatic activity of CEM15/Apobec-3G is essential for the regulation of the infectivity of HIV-1 virion but not a sole determinant of its antiviral activity.

    Science.gov (United States)

    Shindo, Keisuke; Takaori-Kondo, Akifumi; Kobayashi, Masayuki; Abudu, Aierken; Fukunaga, Keiko; Uchiyama, Takashi

    2003-11-07

    Human immunodeficiency virus, type 1 (HIV-1) Vif protein plays an essential role in the regulation of the infectivity of HIV-1 virion. Vif functions to counteract an anti-HIV-1 cellular factor in non-permissive cells, CEM15/Apobec-3G, which shares a cytidine deaminase motif. CEM15/Apobec-3G deaminates dC to dU in the minus strand DNA of HIV-1, resulting in G to A hypermutation in the plus strand DNA. In this study, we have done the mutagenesis analysis on two cytidine deaminase motifs in CEM15/Apobec-3G and examined their antiviral functions as well as the DNA editing activity. Point mutations in the C-terminal active site such as E259Q and C291A almost completely abrogated the antiviral function, while those in the N-terminal active site such as E67Q and C100A retained this activity to a lesser extent as compared with that of the wild type. The DNA editing activities of E67Q and E259Q mutants were both retained but impaired to the same extent. This indicates that the enzymatic activity of this protein is essential but not a sole determinant of the antiviral activity. Furthermore, all the deletion mutants tested in this study lost the antiviral activity because of the loss of the activity for dimerization, suggesting that the entire protein structure is necessary for the antiviral function.

  13. Deletion of the LTR enhancer/promoter has no impact on the integration profile of MLV vectors in human hematopoietic progenitors.

    Directory of Open Access Journals (Sweden)

    Arianna Moiani

    Full Text Available Moloney murine leukemia virus (MLV-derived gamma-retroviral vectors integrate preferentially near transcriptional regulatory regions in the human genome, and are associated with a significant risk of insertional gene deregulation. Self-inactivating (SIN vectors carry a deletion of the U3 enhancer and promoter in the long terminal repeat (LTR, and show reduced genotoxicity in pre-clinical assays. We report a high-definition analysis of the integration preferences of a SIN MLV vector compared to a wild-type-LTR MLV vector in the genome of CD34(+ human hematopoietic stem/progenitor cells (HSPCs. We sequenced 13,011 unique SIN-MLV integration sites and compared them to 32,574 previously generated MLV sites in human HSPCs. The SIN-MLV vector recapitulates the integration pattern observed for MLV, with the characteristic clustering of integrations around enhancer and promoter regions associated to H3K4me3 and H3K4me1 histone modifications, specialized chromatin configurations (presence of the H2A.Z histone variant and binding of RNA Pol II. SIN-MLV and MLV integration clusters and hot spots overlap in most cases and are generated at a comparable frequency, indicating that the reduced genotoxicity of SIN-MLV vectors in hematopoietic cells is not due to a modified integration profile.

  14. Molecular Basis for Drug Resistance in HIV-1 Protease

    Directory of Open Access Journals (Sweden)

    Celia A. Schiffer

    2010-11-01

    Full Text Available HIV-1 protease is one of the major antiviral targets in the treatment of patients infected with HIV-1. The nine FDA approved HIV-1 protease inhibitors were developed with extensive use of structure-based drug design, thus the atomic details of how the inhibitors bind are well characterized. From this structural understanding the molecular basis for drug resistance in HIV-1 protease can be elucidated. Selected mutations in response to therapy and diversity between clades in HIV-1 protease have altered the shape of the active site, potentially altered the dynamics and even altered the sequence of the cleavage sites in the Gag polyprotein. All of these interdependent changes act in synergy to confer drug resistance while simultaneously maintaining the fitness of the virus. New strategies, such as incorporation of the substrate envelope constraint to design robust inhibitors that incorporate details of HIV-1 protease’s function and decrease the probability of drug resistance, are necessary to continue to effectively target this key protein in HIV-1 life cycle.

  15. Comparison of glycerolisation with cryopreservation methods on HIV-1 inactivation

    International Nuclear Information System (INIS)

    Van Baare, J.; Pagnon, J.; Cameron, P.; Vardaxis, N.; Middlekoop, E.; Crowe, S.

    1999-01-01

    Cryopreservation and glycerolisation are two successful long-term preservation methods for human cadaveric donor skin, which is used in the treatment of bum patients. High concentrations of glycerol has been shown to be antibacterial and virucidal. Because fear of possible transmission of HIV-1 following allograft transplantation, this study was undertaken to investigate whether HIV can be effectively eliminated from skin explants. HIV-1 Ba-L, which has been shown to infect monocytes in skin explants and also dendritic cells, was. For the experiments we used cell-free virus, exogenously HIV infected peripheral blood mononuclear cells (PBMCs) and exogenously HIV infected cadaver split skin. Different concentrations of glycerol at various temperatures and the glycerolisation procedure as used by the Euro Skin Bank were used to determine the effects on HIV-1 Ba-L infectivity. For the cryopreservation technique we used 10% DMSO and a controlled rate freezer. HIV-1 Ba-L transfer was determined by adding uninfected PBMCs to the infected material and reverse transcriptase was measured. Cell-free HIV-1 Ba-L was not inactivated by 50% glycerol but was effectively inactivated within 30 minutes by 70% and 85% glycerol at 4 degree C, room temperature and 37 degree C. In contrast, cell-free HIV-1 Ba-L was not inactivated by cryopreservation. Most importantly, we have shown that HIV-1 Ba-L present in split skin is inactivated by incubating skin in 70% glycerol for three hours at 37-C. HIV in exogenously infected skin was not inactivated by cryopreservation. High concentrations of glycerol effectively inactivates free HIV-1 Ba-L and intracellular HIV-1 Ba-L. Also the current glycerolisation procedure carried out by the Euro Skin Bank effectively inactivates infectious virus. However, the cryopreservation technique did not show any reduction in HIV-1 Ba-L infectivity

  16. An anti-HIV microbicide engineered in commensal bacteria: secretion of HIV-1 fusion inhibitors by lactobacilli

    NARCIS (Netherlands)

    Pusch, O.; Kalyanaraman, R.; Tucker, L.D.; Wells, J.; Rmanratnam, B.; Boden, D.

    2006-01-01

    Objectives: To engineer Lactobacillus spp. to secrete HIV-1 fusion inhibitors with potent neutralizing activity against primary HIV-1 isolates. Methods: HIV-1 fusion inhibitors (FI-1, FI-2, and FI-3) were introduced into the previously developed shuttle vector pTSV2 and transformed in L. plantarum

  17. Exosomes from Human Immunodeficiency Virus Type 1 (HIV-1)-Infected Cells License Quiescent CD4+ T Lymphocytes To Replicate HIV-1 through a Nef- and ADAM17-Dependent Mechanism

    OpenAIRE

    Arenaccio, Claudia; Chiozzini, Chiara; Columba-Cabezas, Sandra; Manfredi, Francesco; Affabris, Elisabetta; Baur, Andreas; Federico, Maurizio

    2014-01-01

    Resting CD4+ T lymphocytes resist human immunodeficiency virus (HIV) infection. Here, we provide evidence that exosomes from HIV-1-infected cells render resting human primary CD4+ T lymphocytes permissive to HIV-1 replication. These results were obtained with transwell cocultures of HIV-1-infected cells with quiescent CD4+ T lymphocytes in the presence of inhibitors of exosome release and were confirmed using exosomes purified from supernatants of HIV-1-infected primary CD4+ T lymphocytes. We...

  18. Rational development of radiopharmaceuticals for HIV-1

    International Nuclear Information System (INIS)

    Lau, Chuen-Yen; Maldarelli, Frank; Eckelman, William C.; Neumann, Ronald D.

    2014-01-01

    The global battle against HIV-1 would benefit from a sensitive and specific radiopharmaceutical to localize HIV-infected cells. Ideally, this probe would be able to identify latently infected host cells containing replication competent HIV sequences. Clinical and research applications would include assessment of reservoirs, informing clinical management by facilitating assessment of burden of infection in different compartments, monitoring disease progression and monitoring response to therapy. A “rational” development approach could facilitate efficient identification of an appropriate targeted radiopharmaceutical. Rational development starts with understanding characteristics of the disease that can be effectively targeted and then engineering radiopharmaceuticals to hone in on an appropriate target, which in the case of HIV-1 (HIV) might be an HIV-specific product on or in the host cell, a differentially expressed gene product, an integrated DNA sequence specific enzymatic activity, part of the inflammatory response, or a combination of these. This is different from the current approach that starts with a radiopharmaceutical for a target associated with a disease, mostly from autopsy studies, without a strong rationale for the potential to impact patient care. At present, no targeted therapies are available for HIV latency, although a number of approaches are under study. Here we discuss requirements for a radiopharmaceutical useful in strategies targeting persistently infected cells. The radiopharmaceutical for HIV should be developed based on HIV biology, studied in an animal model and then in humans, and ultimately used in clinical and research settings

  19. Triterpenoids from Ocimum labiatum Activates Latent HIV-1 Expression In Vitro: Potential for Use in Adjuvant Therapy

    Directory of Open Access Journals (Sweden)

    Petrina Kapewangolo

    2017-10-01

    Full Text Available Latent HIV reservoirs in infected individuals prevent current treatment from eradicating infection. Treatment strategies against latency involve adjuvants for viral reactivation which exposes viral particles to antiretroviral drugs. In this study, the effect of novel triterpenoids isolated from Ocimum labiatum on HIV-1 expression was measured through HIV-1 p24 antigen capture in the U1 latency model of HIV-1 infection and in peripheral blood mononuclear cells (PBMCs of infected patients on combination antiretroviral therapy (cART. The mechanism of viral reactivation was determined through the compound’s effect on cytokine production, histone deacetylase (HDAC inhibition, and protein kinase C (PKC activation. Cytotoxicity of the triterpenoids was determined using a tetrazolium dye and flow cytometry. The isolated triterpene isomers, 3-hydroxy-4,6a,6b,11,12,14b-hexamethyl-1,2,3,4,6,6a,6b,7,8,8a,9,10,11,12,12a,14,14a,14b-octadecahydropicene-4,8a-dicarboxylic acid (HHODC, significantly (p < 0.05 induced HIV-1 expression in a dose-dependent manner in U1 cells at non-cytotoxic concentrations. HHODC also induced viral expression in PBMCs of HIV-1 infected patients on cART. In addition, the compound up-regulated the production of interleukin (IL-2, IL-6, tumour necrosis factor (TNF-α, and interferon (IFN-γ but had no effect on HDAC and PKC activity, suggesting cytokine upregulation as being involved in latency activation. The observed in vitro reactivation of HIV-1 introduces the adjuvant potential of HHODC for the first time here.

  20. Clinical Evaluation of an Affordable Qualitative Viral Failure Assay for HIV Using Dried Blood Spots in Uganda.

    Science.gov (United States)

    Balinda, Sheila N; Ondoa, Pascale; Obuku, Ekwaro A; Kliphuis, Aletta; Egau, Isaac; Bronze, Michelle; Kasambula, Lordwin; Schuurman, Rob; Spieker, Nicole; Rinke de Wit, Tobias F; Kityo, Cissy

    2016-01-01

    WHO recommends regular viral load (VL) monitoring of patients on antiretroviral therapy (ART) for timely detection of virological failure, prevention of acquired HIV drug resistance (HIVDR) and avoiding unnecessary switching to second-line ART. However, the cost and complexity of routine VL testing remains prohibitive in most resource limited settings (RLS). We evaluated a simple, low-cost, qualitative viral-failure assay (VFA) on dried blood spots (DBS) in three clinical settings in Uganda. We conducted a cross-sectional diagnostic accuracy study in three HIV/AIDS treatment centres at the Joint Clinical Research Centre in Uganda. The VFA employs semi-quantitative detection of HIV-1 RNA amplified from the LTR gene. We used paired dry blood spot (DBS) and plasma with the COBASAmpliPrep/COBASTaqMan, Roche version 2 (VLref) as the reference assay. We used the VFA at two thresholds of viral load, (>5,000 or >1,000 copies/ml). 496 paired VFA and VLref results were available for comparative analysis. Overall, VFA demonstrated 78.4% sensitivity, (95% CI: 69.7%-87.1%), 93% specificity (95% CI: 89.7%-96.4%), 89.3% accuracy (95% CI: 85%-92%) and an agreement kappa = 0.72 as compared to the VLref. The predictive values of positivity and negativity among patients on ART for >12 months were 72.7% and 99.3%, respectively. VFA allowed 89% of correct classification of VF. Only 11% of the patients were misclassified with the potential of unnecessary or late switch to second-line ART. Our findings present an opportunity to roll out simple and affordable VL monitoring for HIV-1 treatment in RLS.

  1. Clinical Evaluation of an Affordable Qualitative Viral Failure Assay for HIV Using Dried Blood Spots in Uganda.

    Directory of Open Access Journals (Sweden)

    Sheila N Balinda

    Full Text Available WHO recommends regular viral load (VL monitoring of patients on antiretroviral therapy (ART for timely detection of virological failure, prevention of acquired HIV drug resistance (HIVDR and avoiding unnecessary switching to second-line ART. However, the cost and complexity of routine VL testing remains prohibitive in most resource limited settings (RLS. We evaluated a simple, low-cost, qualitative viral-failure assay (VFA on dried blood spots (DBS in three clinical settings in Uganda.We conducted a cross-sectional diagnostic accuracy study in three HIV/AIDS treatment centres at the Joint Clinical Research Centre in Uganda. The VFA employs semi-quantitative detection of HIV-1 RNA amplified from the LTR gene. We used paired dry blood spot (DBS and plasma with the COBASAmpliPrep/COBASTaqMan, Roche version 2 (VLref as the reference assay. We used the VFA at two thresholds of viral load, (>5,000 or >1,000 copies/ml.496 paired VFA and VLref results were available for comparative analysis. Overall, VFA demonstrated 78.4% sensitivity, (95% CI: 69.7%-87.1%, 93% specificity (95% CI: 89.7%-96.4%, 89.3% accuracy (95% CI: 85%-92% and an agreement kappa = 0.72 as compared to the VLref. The predictive values of positivity and negativity among patients on ART for >12 months were 72.7% and 99.3%, respectively.VFA allowed 89% of correct classification of VF. Only 11% of the patients were misclassified with the potential of unnecessary or late switch to second-line ART. Our findings present an opportunity to roll out simple and affordable VL monitoring for HIV-1 treatment in RLS.

  2. Novel host restriction factors implicated in HIV-1 replication.

    Science.gov (United States)

    Ghimire, Dibya; Rai, Madhu; Gaur, Ritu

    2018-04-01

    Human immunodeficiency virus-1 (HIV-1) is known to interact with multiple host cellular proteins during its replication in the target cell. While many of these host cellular proteins facilitate viral replication, a number of them are reported to inhibit HIV-1 replication at various stages of its life cycle. These host cellular proteins, which are known as restriction factors, constitute an integral part of the host's first line of defence against the viral pathogen. Since the discovery of apolipoprotein B mRNA-editing enzyme 3G (APOBEC3G) as an HIV-1 restriction factor, several human proteins have been identified that exhibit anti-HIV-1 restriction. While each restriction factor employs a distinct mechanism of inhibition, the HIV-1 virus has equally evolved complex counter strategies to neutralize their inhibitory effect. APOBEC3G, tetherin, sterile alpha motif and histidine-aspartate domain 1 (SAMHD1), and trim-5α are some of the best known HIV-1 restriction factors that have been studied in great detail. Recently, six novel restriction factors were discovered that exhibit significant antiviral activity: endoplasmic reticulum α1,2-mannosidase I (ERManI), translocator protein (TSPO), guanylate-binding protein 5 (GBP5), serine incorporator (SERINC3/5) and zinc-finger antiviral protein (ZAP). The focus of this review is to discuss the antiviral mechanism of action of these six restriction factors and provide insights into the probable counter-evasion strategies employed by the HIV-1 virus. The recent discovery of new restriction factors substantiates the complex host-pathogen interactions occurring during HIV-1 pathogenesis and makes it imperative that further investigations are conducted to elucidate the molecular basis of HIV-1 replication.

  3. HIV-1 persistence following extremely early initiation of antiretroviral therapy (ART during acute HIV-1 infection: An observational study.

    Directory of Open Access Journals (Sweden)

    Timothy J Henrich

    2017-11-01

    Full Text Available It is unknown if extremely early initiation of antiretroviral therapy (ART may lead to long-term ART-free HIV remission or cure. As a result, we studied 2 individuals recruited from a pre-exposure prophylaxis (PrEP program who started prophylactic ART an estimated 10 days (Participant A; 54-year-old male and 12 days (Participant B; 31-year-old male after infection with peak plasma HIV RNA of 220 copies/mL and 3,343 copies/mL, respectively. Extensive testing of blood and tissue for HIV persistence was performed, and PrEP Participant A underwent analytical treatment interruption (ATI following 32 weeks of continuous ART.Colorectal and lymph node tissues, bone marrow, cerebral spinal fluid (CSF, plasma, and very large numbers of peripheral blood mononuclear cells (PBMCs were obtained longitudinally from both participants and were studied for HIV persistence in several laboratories using molecular and culture-based detection methods, including a murine viral outgrowth assay (mVOA. Both participants initiated PrEP with tenofovir/emtricitabine during very early Fiebig stage I (detectable plasma HIV-1 RNA, antibody negative followed by 4-drug ART intensification. Following peak viral loads, both participants experienced full suppression of HIV-1 plasma viremia. Over the following 2 years, no further HIV could be detected in blood or tissue from PrEP Participant A despite extensive sampling from ileum, rectum, lymph nodes, bone marrow, CSF, circulating CD4+ T cell subsets, and plasma. No HIV was detected from tissues obtained from PrEP Participant B, but low-level HIV RNA or DNA was intermittently detected from various CD4+ T cell subsets. Over 500 million CD4+ T cells were assayed from both participants in a humanized mouse outgrowth assay. Three of 8 mice infused with CD4+ T cells from PrEP Participant B developed viremia (50 million input cells/surviving mouse, but only 1 of 10 mice infused with CD4+ T cells from PrEP Participant A (53 million input

  4. HIV-1 replication in cell lines harboring INI1/hSNF5 mutations

    Directory of Open Access Journals (Sweden)

    Wu Xuhong

    2006-08-01

    Full Text Available Abstract Background INI1/hSNF5 is a cellular protein that directly interacts with HIV-1 integrase (IN. It is specifically incorporated into HIV-1 virions. A dominant negative mutant derived from INI1 inhibits HIV-1 replication. Recent studies indicate that INI1 is associated with pre-integration and reverse transcription complexes that are formed upon viral entry into the target cells. INI1 also is a tumor suppressor, biallelically deleted/mutated in malignant rhabdoid tumors. We have utilized cell lines derived from the rhabdoid tumors, MON and STA-WT1, that harbor either null or truncating mutations of INI1 respectively, to assess the effect of INI1 on HIV-1 replication. Results We found that while HIV-1 virions produced in 293T cells efficiently transduced MON and STA-WT1 cells, HIV-1 particle production was severely reduced in both of these cells. Reintroduction of INI1 into MON and STA-WT1 significantly enhanced the particle production in both cell lines. HIV-1 particles produced in MON cells were reduced for infectivity, while those produced in STA-WT1 were not. Further analysis indicated the presence of INI1 in those virions produced from STA-WT1 but not from those produced from MON cells. HIV-1 produced in MON cells were defective for synthesis of early and late reverse transcription products in the target cells. Furthermore, virions produced in MON cells were defective for exogenous reverse transcriptase activity carried out using exogenous template, primer and substrate. Conclusion Our results suggest that INI1-deficient cells exhibit reduced particle production that can be partly enhanced by re-introduction of INI1. Infectivity of HIV-1 produced in some but not all INI1 defective cells, is affected and this defect may correlate to the lack of INI1 and/or some other proteins in these virions. The block in early events of virion produced from MON cells appears to be at the stage of reverse transcription. These studies suggest that

  5. HIV-1 replication in cell lines harboring INI1/hSNF5 mutations.

    Science.gov (United States)

    Sorin, Masha; Yung, Eric; Wu, Xuhong; Kalpana, Ganjam V

    2006-08-31

    INI1/hSNF5 is a cellular protein that directly interacts with HIV-1 integrase (IN). It is specifically incorporated into HIV-1 virions. A dominant negative mutant derived from INI1 inhibits HIV-1 replication. Recent studies indicate that INI1 is associated with pre-integration and reverse transcription complexes that are formed upon viral entry into the target cells. INI1 also is a tumor suppressor, biallelically deleted/mutated in malignant rhabdoid tumors. We have utilized cell lines derived from the rhabdoid tumors, MON and STA-WT1, that harbor either null or truncating mutations of INI1 respectively, to assess the effect of INI1 on HIV-1 replication. We found that while HIV-1 virions produced in 293T cells efficiently transduced MON and STA-WT1 cells, HIV-1 particle production was severely reduced in both of these cells. Reintroduction of INI1 into MON and STA-WT1 significantly enhanced the particle production in both cell lines. HIV-1 particles produced in MON cells were reduced for infectivity, while those produced in STA-WT1 were not. Further analysis indicated the presence of INI1 in those virions produced from STA-WT1 but not from those produced from MON cells. HIV-1 produced in MON cells were defective for synthesis of early and late reverse transcription products in the target cells. Furthermore, virions produced in MON cells were defective for exogenous reverse transcriptase activity carried out using exogenous template, primer and substrate. Our results suggest that INI1-deficient cells exhibit reduced particle production that can be partly enhanced by re-introduction of INI1. Infectivity of HIV-1 produced in some but not all INI1 defective cells, is affected and this defect may correlate to the lack of INI1 and/or some other proteins in these virions. The block in early events of virion produced from MON cells appears to be at the stage of reverse transcription. These studies suggest that presence of INI1 or some other host factor in virions and

  6. HIV-1 infection during pregnancy and in children : significance of HIV-1 variability and the placental barrier

    OpenAIRE

    Casper, Charlotte

    2001-01-01

    With the global increase in human immunodeficiency virus 1 (HIV-1) infection in women of childbearing age, there has also been an alarming increase in the number of mother-to-child transmissions of HIV-1. Although antiretroviral therapy and Cesarian section have been demonstrated to significantly decrease the vertical transmission rate of , these interventions are not widely available in the developing world. Therefore, studies of the mechanisms of vertical transmission are ...

  7. CCL28 induces mucosal homing of HIV-1-specific IgA-secreting plasma cells in mice immunized with HIV-1 virus-like particles.

    Directory of Open Access Journals (Sweden)

    Veronica Rainone

    Full Text Available Mucosae-associated epithelial chemokine (MEC or CCL28 binds to CCR3 and CCR10 and recruits IgA-secreting plasma cells (IgA-ASCs in the mucosal lamina propria. The ability of this chemokine to enhance migration of IgA-ASCs to mucosal sites was assessed in a mouse immunization model using HIV-1(IIIB Virus-like particles (VLPs. Mice receiving either HIV-1(IIIB VLPs alone, CCL28 alone, or the irrelevant CCL19 chemokine were used as controls. Results showed a significantly increased CCR3 and CCR10 expression on CD19(+ splenocytes of HIV-1(IIIB VPL-CCL28-treated mice. HIV-1 Env-specific IFN-γ, IL-4 and IL-5 production, total IgA, anti-Env IgA as well as gastro-intestinal mucosal IgA-secreting plasma cells were also significantly augmented in these mice. Notably, sera and vaginal secretions from HIV-1(IIIB VLP-CCL28-treated mice exhibited an enhanced neutralizing activity against both a HIV-1/B-subtype laboratory strain and a heterologous HIV-1/C-subtype primary isolate. These data suggest that CCL28 could be useful in enhancing the IgA immune response that will likely play a pivotal role in prophylactic HIV vaccines.

  8. Antiviral Therapy by HIV-1 Broadly Neutralizing and Inhibitory Antibodies

    Directory of Open Access Journals (Sweden)

    Zhiqing Zhang

    2016-11-01

    Full Text Available Human immunodeficiency virus type 1 (HIV-1 infection causes acquired immune deficiency syndrome (AIDS, a global epidemic for more than three decades. HIV-1 replication is primarily controlled through antiretroviral therapy (ART but this treatment does not cure HIV-1 infection. Furthermore, there is increasing viral resistance to ART, and side effects associated with long-term therapy. Consequently, there is a need of alternative candidates for HIV-1 prevention and therapy. Recent advances have discovered multiple broadly neutralizing antibodies against HIV-1. In this review, we describe the key epitopes on the HIV-1 Env protein and the reciprocal broadly neutralizing antibodies, and discuss the ongoing clinical trials of broadly neutralizing and inhibitory antibody therapy as well as antibody combinations, bispecific antibodies, and methods that improve therapeutic efficacy by combining broadly neutralizing antibodies (bNAbs with latency reversing agents. Compared with ART, HIV-1 therapeutics that incorporate these broadly neutralizing and inhibitory antibodies offer the advantage of decreasing virus load and clearing infected cells, which is a promising prospect in HIV-1 prevention and treatment.

  9. Molecular mechanisms of HIV-1 associated neurodegeneration

    Indian Academy of Sciences (India)

    Since identification of the human immunodeficiency virus-1 (HIV-1), numerous studies suggest a link between neurological impairments, in particular dementia, with acquired immunodeficiency syndrome (AIDS) with alarming occurrence worldwide. Approximately, 60% of HIV-infected people show some form of neurological ...

  10. Viral dynamics in primary HIV-1 infection. Karolinska Institutet Primary HIV Infection Study Group.

    Science.gov (United States)

    Lindbäck, S; Karlsson, A C; Mittler, J; Blaxhult, A; Carlsson, M; Briheim, G; Sönnerborg, A; Gaines, H

    2000-10-20

    To study the natural course of viremia during primary HIV infection (PHI). Eight patients were followed from a median of 5 days from the onset of PHI illness. Plasma HIV-1 RNA levels were measured frequently and the results were fitted to mathematical models. HIV-1 RNA levels were also monitored in nine patients given two reverse transcriptase inhibitors and a protease inhibitor after a median of 7 days from the onset of PHI illness. HIV-1 RNA appeared in the blood during the week preceding onset of PHI illness and increased rapidly during the first viremic phase, reaching a peak at a mean of 7 days after onset of illness. This was followed by a phase of rapidly decreasing levels of HIV-1 RNA to an average of 21 days after onset. Viral density continued to decline thereafter but at a 5- to 50-fold lower rate; a steady-state level was reached at a median of 2 months after onset of PHI. Peak viral density levels correlated significantly with levels measured between days 50 and 600. Initiation of antiretroviral treatment during PHI resulted in rapidly declining levels to below 50 copies/mL. This study demonstrates the kinetic phases of viremia during PHI and indicates two new contributions to the natural history of HIV-1 infection: PHI peak levels correlate with steady-state levels and HIV-1 RNA declines biphasically; an initial rapid decay is usually followed by a slow decay, which is similar to the initial changes seen with antiviral treatment.

  11. Evaluation of four rapid tests for diagnosis and differentiation of HIV-1 and HIV-2 infections in Guinea-Conakry, West Africa.

    OpenAIRE

    Chaillet, Pascale; Tayler-Smith, Katie; Zachariah, Rony; Duclos, Nanfack; Moctar, Diallo; Beelaert, Greet; Fransen, Katrien

    2010-01-01

    With both HIV-1 and HV-2 prevalent in Guinea-Conakry, accurate diagnosis and differentiation is crucial for treatment purposes. Thus, four rapid HIV tests were evaluated for their HIV-1 and HIV-2 diagnostic and discriminative capacity for use in Guinea-Conakry. These included SD Bioline HIV 1/2 3.0 (Standard Diagnostics Inc.), Genie II HIV1/HIV2 (Bio-Rad), First Response HIV Card Test 1-2.0 (PMC Medical) and Immunoflow HIV1-HIV2 (Core Diagnostics). Results were compared with gold standard tes...

  12. Cerebrospinal fluid HIV-1 RNA levels in asymptomatic patients with early stage chronic HIV-1 infection: support for the hypothesis of local virus replication.

    Science.gov (United States)

    García, F; Niebla, G; Romeu, J; Vidal, C; Plana, M; Ortega, M; Ruiz, L; Gallart, T; Clotet, B; Miró, J M; Pumarola, T; Gatell, J M

    1999-08-20

    To assess HIV-1 RNA levels in cerebrospinal fluid (CSF) and their potential correlation with plasma viral load and central nervous system (CNS) HIV-1 infection markers in stable asymptomatic patients with a CD4 T cell count >500x10(6) cells/l. Consecutive patients screened for two trials were eligible for lumbar puncture assessment. At day 0, simultaneous samples of CSF and plasma were obtained and levels of total proteins, albumin, IgG, antibodies against HIV-1 p24 antigen, HIV-1 RNA (using the polymerase chain technique) and white cells were measured. The integrity of the blood-brain barrier was preserved (albumin index > or =7) in 59 out of 70 patients (84%). Intrathecal production of antibodies against HIV-1 p24 antigen was demonstrated in 55 out of 70 individuals (78%). Viral load in CSF was significantly lower than plasma values (3.13+/-0.95 versus 4.53+/-0.53, P = 0.0001). HIV-1 RNA was not detected in CSF in only three of the 70 patients (4%). Overall, there was a significant correlation between plasma and CSF HIV-1 RNA levels (r = 0.43, P = 0.0001); however, in 29 patients (41%) there were significant differences (>1.5 log10 copies/ml) between the viral loads in plasma and CSF. In the multivariate analysis, a high level of protein and white cells in CSF, but not the HIV-1 RNA plasma level, were factors independently associated with a higher level of HIV-1 RNA in CSF (P = 0.0001). HIV-1 RNA can be detected almost always in CSF of asymptomatic patients in early stages of HIV-1 infection including those with a preserved integrity of the blood-brain barrier. The important discrepancies between plasma and CSF viral load, and the independent association between CSF abnormalities and CSF viral load, support the hypothesis of local production of HIV-1.

  13. Characteristics of HIV-2 and HIV-1/HIV-2 Dually Seropositive Adults in West Africa Presenting for Care and Antiretroviral Therapy

    DEFF Research Database (Denmark)

    Ekouevi, Didier K; Balestre, Eric; Coffie, Patrick A

    2013-01-01

    HIV-2 is endemic in West Africa. There is a lack of evidence-based guidelines on the diagnosis, management and antiretroviral therapy (ART) for HIV-2 or HIV-1/HIV-2 dual infections. Because of these issues, we designed a West African collaborative cohort for HIV-2 infection within the framework o...... of the International epidemiological Databases to Evaluate AIDS (IeDEA)....

  14. HIV-1 subtypes D and F are prevalent in Guinea Conakry.

    Science.gov (United States)

    Freimanis, G L; Loua, A; Allain, J P

    2012-04-01

    Limited data is available upon the distribution of different HIV-1/2 genotypes in the blood donor population from Guinea Conakry. To investigate the prevalence of HIV-1/2 subtypes in asymptomatic blood donors in Guinea Conakry, in order to update knowledge of HIV-1/2 epidemiology within this country. Samples from 104 blood donors seropositive for HIV-1/2 were tested for HIV-1 by real-time RT-PCR. Those negative for HIV-1 were tested with HIV-2 nested RT-PCR. Positive samples were further amplified in the HIV-1 gag and pol regions and sequenced. Subtypes were determined by phylogenetic analysis on amplicon sequences. 61 samples were positive by HIV-1 real-time RT-PCR. Of the 43 negative, 2 (4.6%) were positive for HIV-2. 52/61 (85.3%) samples were positive by nested RT-PCR. Of the 52, 43 (70.5%) and 31(59.6%) sequences were obtained in the gag and pol regions, respectively; 23 for both regions. HIV-1 subtype distribution was 1 B (2.1%), 8 F (17%), 8 D (17%) and 28 CRF02_AG (59.6%) with 2 unclassified recombinants (4.3%). Unique clusters for subtype D and F distinguished Guinea from HIV-1 subtype distribution in neighboring countries. Subtype F and subtype D strains, uncommon in West Africa, are a substantial part of HIV-1 epidemiology in Guinea. Copyright © 2011 Elsevier B.V. All rights reserved.

  15. Minor drug-resistant HIV type-1 variants in breast milk and plasma of HIV type-1-infected Ugandan women after nevirapine single-dose prophylaxis.

    Science.gov (United States)

    Pilger, Daniel; Hauser, Andrea; Kuecherer, Claudia; Mugenyi, Kizito; Kabasinguzi, Rose; Somogyi, Sybille; Harms, Gundel; Kunz, Andrea

    2011-01-01

    Nevirapine single-dose (NVP-SD) reduces mother-to-child transmission of HIV type-1 (HIV-1), but frequently induces resistance mutations in the HIV-1 genome. Little is known about drug-resistant HIV-1 variants in the breast milk of women who have taken NVP-SD. Blood and breast milk samples of 39 HIV-1-infected Ugandan women were taken 6-12 weeks after NVP-SD intake. Samples were analysed by population sequencing and allele-specific real-time PCR (AS-PCR) with detection limits for NVP-resistant HIV-1 variants (K103N and Y181C) of D n = 5, G n = 2 and C n = 1). A total of 7 (37%) and 10 (53%) women carried NVP-resistant virus in breast milk and plasma, respectively. Overall, 71% (5/7) women with NVP-resistant HIV-1 in breast milk displayed >1 drug-resistant variant. Resistance in breast milk was higher at week 6 (6/13 samples [46%]) compared with week 12 (1/6 samples [17%]). In total, 10 drug-resistant populations harbouring the K103N and/or Y181C mutation were detected in the 19 breast milk samples; 7 (70%) were caused by resistant minorities (< 5% of the total HIV-1 population). In the four women with drug-resistant virus in both plasma and breast milk, the mutation patterns differed between the two compartments. Minor populations of drug-resistant HIV-1 were frequently found in breast milk of Ugandan women after exposure to NVP-SD. Further studies need to explore the role of minor drug-resistant variants in the postnatal transmission of (resistant) HIV-1.

  16. Comparison of the Abbott m2000 HIV-1 Real-Time and Roche AMPLICOR Monitor v1.5 HIV-1 assays on plasma specimens from Rakai, Uganda.

    Science.gov (United States)

    Ssebugenyi, I; Kizza, A; Mpoza, B; Aluma, G; Boaz, I; Newell, K; Laeyendecker, O; Shott, J P; Serwadda, D; Reynolds, S J

    2011-07-01

    The need for viral load (VL) monitoring of HIV patients receiving antiretroviral therapy (ART) in resource-limited settings (RLS) has become apparent with studies showing the limitations of immunological monitoring. We compared the Abbott m2000 Real-Time (Abbott) HIV-1 assay with the Roche AMPLICOR Monitor v1.5 (Roche) HIV-1 assay over a range of VL concentrations. Three hundred and eleven plasma samples were tested, including 164 samples from patients on ART ≥ six months and 147 from ART-naïve patients. The Roche assay detected ≥400 copies/mL in 158 (50.8%) samples. Of these, Abbott produced 145 (91.8%) detectable results ≥400 copies/mL; 13 (8.2%) samples produced discrepant results. Concordance between the assays for detecting HIV-1 RNA ≥400 copies/mL was 95.8% (298/311). The sensitivity, specificity, positive predictive value and negative predictive value of Abbott to detect HIV-1 RNA ≥400 copies/mL were 91.8%, 100%, 100% and 92.2%, respectively. For the 151 samples with HIV-1 RNA ≥400 copies/mL for both assays, a good linear correlation was found (r = 0.81, P Abbott assay performed well in our setting, offering an alternative methodology for HIV-1 VL for laboratories with realtime polymerase chain reaction (PCR) capacity.

  17. Introduction of HIV type 1 into an isolated population

    DEFF Research Database (Denmark)

    Madsen, Tina V; Leitner, Thomas; Lohse, Nicolai

    2007-01-01

    Introduction of HIV-1 into a population may not always give rise to a subsequent epidemic. Greenland is an isolated and sparsely populated island in The Danish Kingdom. We aimed to estimate the number of introductions of HIV-1 into Greenland, the number of subsequent epidemics, and the countries...... from which the virus was introduced. Phylogenetic analyses were performed on three regions of HIV-1 (gag, pol, and env) in samples from 70 Greenlandic patients. Furthermore, we included gene sequences from contemporary Danish HIV-1-infected patients and sequences from the Los Alamos HIV Sequence...... Database. All Greenlandic sequences were subtype B except one sequence found to be a recombinant (probably CRF13). Sequence clusters in the phylogenetic trees indicated that there had been at least nine introductions of HIV-1 into Greenland. One cluster, supported by bootstrap values of 81, 76, and 96...

  18. Bacterial vaginosis, alterations in vaginal flora and HIV genital shedding among HIV-1-infected women in Mozambique

    Directory of Open Access Journals (Sweden)

    Robert D Kirkcaldy

    2011-05-01

    Full Text Available Objectives. We investigated whether abnormal vaginal flora, including bacterial vaginosis (BV, are associated with detection of cervical HIV-1 RNA among HIV-infected women in Mozambique. Methods. We obtained clinical data and vaginal specimens from HIV-infected women registering for their first visit at one of two HIV care clinics in Mozambique. We compared women with detectable cervical HIV viral load (≥40 copies/ml with women with undetectable cervical HIV. Results. We enrolled 106 women. Women with abnormal vaginal flora (intermediate Nugent scores, 4 - 6 were more likely to have detectable cervical HIV RNA then women with normal vaginal flora (adjusted odds ratio 7.2 (95% confidence interval 1.8 - 29.1, adjusted for CD4 count. Women with BV had a non-significantly higher likelihood of detectable cervical HIV than women with normal flora. Conclusions. Abnormal vaginal flora were significantly associated with cervical HIV expression. Further research is needed to confirm this relationship.

  19. Transcriptional Modulation of Human Endogenous Retroviruses in Primary CD4+ T Cells Following Vorinostat Treatment

    Directory of Open Access Journals (Sweden)

    Cory H. White

    2018-04-01

    Full Text Available The greatest obstacle to a cure for HIV is the provirus that integrates into the genome of the infected cell and persists despite antiretroviral therapy. A “shock and kill” approach has been proposed as a strategy for an HIV cure whereby drugs and compounds referred to as latency-reversing agents (LRAs are used to “shock” the silent provirus into active replication to permit “killing” by virus-induced pathology or immune recognition. The LRA most utilized to date in clinical trials has been the histone deacetylase (HDAC inhibitor—vorinostat. Potentially, pathological off-target effects of vorinostat may result from the activation of human endogenous retroviruses (HERVs, which share common ancestry with exogenous retroviruses including HIV. To explore the effects of HDAC inhibition on HERV transcription, an unbiased pharmacogenomics approach (total RNA-Seq was used to evaluate HERV expression following the exposure of primary CD4+ T cells to a high dose of vorinostat. Over 2,000 individual HERV elements were found to be significantly modulated by vorinostat, whereby elements belonging to the ERVL family (e.g., LTR16C and LTR33 were predominantly downregulated, in contrast to LTR12 elements of the HERV-9 family, which exhibited the greatest signal, with the upregulation of 140 distinct elements. The modulation of three different LTR12 elements by vorinostat was confirmed by droplet digital PCR along a dose–response curve. The monitoring of LTR12 expression during clinical trials with vorinostat may be indicated to assess the impact of this HERV on the human genome and host immunity.

  20. Sensitive non-radioactive detection of HIV-1

    DEFF Research Database (Denmark)

    Teglbjærg, Lars Stubbe; Nielsen, C; Hansen, J E

    1992-01-01

    This report describes the use of the polymerase chain reaction (PCR) for the non-radioactive detection of HIV-1 proviral genomic sequences in HIV-1 infected cells. We have developed a sensitive assay, using three different sets of nested primers and our results show that this method is superior...... to standard PCR for the detection of HIV-1 DNA. The assay described features the use of a simple and inexpensive sample preparation technique and a non-radioactive hybridization procedure for confirmation of results. To test the suitability of the assay for clinical purposes, we tested cell samples from 76...

  1. Characteristics of HIV-2 and HIV-1/HIV-2 Dually Seropositive Adults in West Africa Presenting for Care and Antiretroviral Therapy: The IeDEA-West Africa HIV-2 Cohort Study.

    Science.gov (United States)

    Ekouevi, Didier K; Balestre, Eric; Coffie, Patrick A; Minta, Daouda; Messou, Eugene; Sawadogo, Adrien; Minga, Albert; Sow, Papa Salif; Bissagnene, Emmanuel; Eholie, Serge P; Gottlieb, Geoffrey S; Dabis, François; Zannou, Djimon Marcel; Ahouada, Carin; Akakpo, Jocelyn; Ahomadegbé, Christelle; Bashi, Jules; Gougounon-Houéto, Alice; Azon-Kouanou, Angèle; Houngbé, Fabien; Koumakpaï, Sikiratou; Alihonou, Florence; d'Almeida, Marcelline; Hodonou, Irvine; Hounhoui, Ghislaine; Sagbo, Gracien; Tossa-Bagnan, Leïla; Adjide, Herman; Drabo, Joseph; Bognounou, René; Dienderé, Arnaud; Traore, Eliezer; Zoungrana, Lassane; Zerbo, Béatrice; Sawadogo, Adrien Bruno; Zoungrana, Jacques; Héma, Arsène; Soré, Ibrahim; Bado, Guillaume; Tapsoba, Achille; Yé, Diarra; Kouéta, Fla; Ouedraogo, Sylvie; Ouédraogo, Rasmata; Hiembo, William; Gansonré, Mady; Messou, Eugène; Gnokoro, Joachim Charles; Koné, Mamadou; Kouakou, Guillaume Martial; Bosse, Clarisse Amani; Brou, Kouakou; Assi, Achi Isidore; Chenal, Henri; Hawerlander, Denise; Soppi, Franck; Minga, Albert; Abo, Yao; Bomisso, Germain; Eholié, Serge Paul; Amego, Mensah Deborah Noelly; Andavi, Viviane; Diallo, Zelica; Ello, Frédéric; Tanon, Aristophane Koffi; Koule, Serge Olivier; Anzan, Koffi Charles; Guehi, Calixte; Aka, Edmond Addi; Issouf, Koffi Ladji; Kouakou, Jean-Claude; N'gbeche, Marie-Sylvie; Touré, Pety; Avit-Edi, Divine; Kouakou, Kouadio; Moh, Magloire; Yao, Valérie Andoblé; Folquet, Madeleine Amorissani; Dainguy, Marie-Evelyne; Kouakou, Cyrille; Méa-Assande, Véronique Tanoh; Oka-Berete, Gladys; Zobo, Nathalie; Acquah, Patrick; Kokora, Marie-Berthe; Eboua, Tanoh François; Timité-Konan, Marguerite; Ahoussou, Lucrèce Diecket; Assouan, Julie Kebé; Sami, Mabéa Flora; Kouadio, Clémence; Renner, Lorna; Goka, Bamenla; Welbeck, Jennifer; Sackey, Adziri; Owiafe, Seth Ntiri; Wejse, Christian; Silva, Zacarias José Da; Paulo, Joao; Rodrigues, Amabelia; da Silva, David; Medina, Candida; Oliviera-Souto, Ines; Ostergaard, Lars; Laursen, Alex; Sodemann, Morten; Aaby, Peter; Fomsgaard, Anders; Erikstrup, Christian; Eugen-Olsen, Jesper; Maïga, Moussa Y; Diakité, Fatoumata Fofana; Kalle, Abdoulaye; Katile, Drissa; Traore, Hamar Alassane; Minta, Daouda; Cissé, Tidiani; Dembelé, Mamadou; Doumbia, Mohammed; Fomba, Mahamadou; Kaya, Assétou Soukho; Traoré, Abdoulaye M; Traoré, Hamady; Toure, Amadou Abathina; Dicko, Fatoumata; Sylla, Mariam; Berthé, Alima; Traoré, Hadizatou Coulibaly; Koïta, Anta; Koné, Niaboula; N'diaye, Clémentine; Coulibaly, Safiatou Touré; Traoré, Mamadou; Traoré, Naïchata; Charurat, Man; Ajayi, Samuel; Dapiap, Stephen; Otu; Igbinoba, Festus; Benson, Okwara; Adebamowo, Clément; James, Jesse; Obaseki; Osakede, Philip; Olasode, John; Sow, Papa Salif; Diop, Bernard; Manga, Noël Magloire; Tine, Judicael Malick; Signate Sy, Haby; Ba, Abou; Diagne, Aida; Dior, Hélène; Faye, Malick; Gueye, Ramatoulaye Diagne; Mbaye, Aminata Diack; Patassi, Akessiwe; Kotosso, Awèrou; Kariyare, Benjamin Goilibe; Gbadamassi, Gafarou; Komi, Agbo; Mensah-Zukong, Kankoé Edem; Pakpame, Pinuwe; Lawson-Evi, Annette Koko; Atakouma, Yawo; Takassi, Elom; Djeha, Améyo; Ephoévi-Gah, Ayoko; Djibril, Sherifa El-Hadj; Dabis, François; Bissagnene, Emmanuel; Arrivé, Elise; Coffie, Patrick; Ekouevi, Didier; Jaquet, Antoine; Leroy, Valériane; Lewden, Charlotte; Sasco, Annie; Azani, Jean-Claude; Allou, Gérard; Balestre, Eric; Bohossou, Franck; Karcher, Sophie; Gonsan, Jules Mahan; Carrou, Jérôme Le; Lenaud, Séverin; Nchot, Célestin; Malateste, Karen; Yao, Amon Roseamonde; Siloué, Bertine; Clouet, Gwenaelle; Djetouan, Hugues; Doring, Alexandra; Kouakou, Adrienne; Rabourdin, Elodie; Rivenc, Jean; Anglaret, Xavier; Ba, Boubacar; Essanin, Jean Bosco; Ciaranello, Andrea; Datté, Sébastien; Desmonde, Sophie; Diby, Jean-Serge Elvis; Gottlieb, Geoffrey S; Horo, Apollinaire Gninlgninrin; Kangah, Serge N'zoré; Malvy, Denis; Meless, David; Mounkaila-Harouna, Aida; Ndondoki, Camille; Shiboski, Caroline; Thiébaut, Rodolphe; Pac-Ci; Abidjan

    2013-01-01

    HIV-2 is endemic in West Africa. There is a lack of evidence-based guidelines on the diagnosis, management and antiretroviral therapy (ART) for HIV-2 or HIV-1/HIV-2 dual infections. Because of these issues, we designed a West African collaborative cohort for HIV-2 infection within the framework of the International epidemiological Databases to Evaluate AIDS (IeDEA). We collected data on all HIV-2 and HIV-1/HIV-2 dually seropositive patients (both ARV-naive and starting ART) and followed-up in clinical centres in the IeDEA-WA network including a total of 13 clinics in five countries: Benin, Burkina-Faso Côte d'Ivoire, Mali, and Senegal, in the West Africa region. Data was merged for 1,754 patients (56% female), including 1,021 HIV-2 infected patients (551 on ART) and 733 dually seropositive for both HIV-1 and HIV 2 (463 on ART). At ART initiation, the median age of HIV-2 patients was 45.3 years, IQR: (38.3-51.7) and 42.4 years, IQR (37.0-47.3) for dually seropositive patients (p = 0.048). Overall, 16.7% of HIV-2 patients on ART had an advanced clinical stage (WHO IV or CDC-C). The median CD4 count at the ART initiation is 166 cells/mm(3), IQR (83-247) among HIV-2 infected patients and 146 cells/mm(3), IQR (55-249) among dually seropositive patients. Overall, in ART-treated patients, the CD4 count increased 126 cells/mm(3) after 24 months on ART for HIV-2 patients and 169 cells/mm(3) for dually seropositive patients. Of 551 HIV-2 patients on ART, 5.8% died and 10.2% were lost to follow-up during the median time on ART of 2.4 years, IQR (0.7-4.3). This large multi-country study of HIV-2 and HIV-1/HIV-2 dual infection in West Africa suggests that routine clinical care is less than optimal and that management and treatment of HIV-2 could be further informed by ongoing studies and randomized clinical trials in this population.

  2. Characteristics of HIV-2 and HIV-1/HIV-2 Dually Seropositive Adults in West Africa Presenting for Care and Antiretroviral Therapy: The IeDEA-West Africa HIV-2 Cohort Study.

    Directory of Open Access Journals (Sweden)

    Didier K Ekouevi

    Full Text Available HIV-2 is endemic in West Africa. There is a lack of evidence-based guidelines on the diagnosis, management and antiretroviral therapy (ART for HIV-2 or HIV-1/HIV-2 dual infections. Because of these issues, we designed a West African collaborative cohort for HIV-2 infection within the framework of the International epidemiological Databases to Evaluate AIDS (IeDEA.We collected data on all HIV-2 and HIV-1/HIV-2 dually seropositive patients (both ARV-naive and starting ART and followed-up in clinical centres in the IeDEA-WA network including a total of 13 clinics in five countries: Benin, Burkina-Faso Côte d'Ivoire, Mali, and Senegal, in the West Africa region.Data was merged for 1,754 patients (56% female, including 1,021 HIV-2 infected patients (551 on ART and 733 dually seropositive for both HIV-1 and HIV 2 (463 on ART. At ART initiation, the median age of HIV-2 patients was 45.3 years, IQR: (38.3-51.7 and 42.4 years, IQR (37.0-47.3 for dually seropositive patients (p = 0.048. Overall, 16.7% of HIV-2 patients on ART had an advanced clinical stage (WHO IV or CDC-C. The median CD4 count at the ART initiation is 166 cells/mm(3, IQR (83-247 among HIV-2 infected patients and 146 cells/mm(3, IQR (55-249 among dually seropositive patients. Overall, in ART-treated patients, the CD4 count increased 126 cells/mm(3 after 24 months on ART for HIV-2 patients and 169 cells/mm(3 for dually seropositive patients. Of 551 HIV-2 patients on ART, 5.8% died and 10.2% were lost to follow-up during the median time on ART of 2.4 years, IQR (0.7-4.3.This large multi-country study of HIV-2 and HIV-1/HIV-2 dual infection in West Africa suggests that routine clinical care is less than optimal and that management and treatment of HIV-2 could be further informed by ongoing studies and randomized clinical trials in this population.

  3. In vivo activation of human immunodeficiency virus type 1 long terminal repeat by UV type A (UV-A) light plus psoralen and UV-B light in the skin of transgenic mice

    OpenAIRE

    Morrey, John D; Bourn, S M; Bunch, T D; Jackson, M K; Sidwell, R W; Barrows, L R; Daynes, R A; Rosen, C A

    1991-01-01

    UV irradiation has been shown to activate the human immunodeficiency virus type 1 (HIV-1) long terminal repeat (LTR) in cell culture; however, only limited studies have been described in vivo. UV light has been categorized as UV-A (400 to 315 nm), -B (315 to 280 nm), or -C (less than 280 nm); the longer wavelengths are less harmful but more penetrative. Highly penetrative UV-A radiation constitutes the vast majority of UV sunlight reaching the earth's surface but is normally harmless. UV-B ir...

  4. Performance of 3 Rapid Tests for Discrimination Between HIV-1 and HIV-2 in Guinea-Bissau, West Africa

    DEFF Research Database (Denmark)

    Hønge, Bo Langhoff; Bjarnason Obinah, Magnús Pétur; Jespersen, Sanne

    2014-01-01

    As HIV-2 is intrinsically resistant to nonnucleoside reverse transcriptase inhibitors, it is mandatory to discriminate between HIV types before initiating antiretroviral treatment. Guinea-Bissau has the world's highest prevalence of HIV-2 and HIV-1/HIV-2 dually infected individuals. We evaluated ...... (agreement 90.9%) and SD Bioline HIV-1/2 3.0 (agreement 84.5%). Our results underscore the need for evaluation of tests in relevant populations before implementation....

  5. IFITM Proteins Restrict HIV-1 Infection by Antagonizing the Envelope Glycoprotein

    Directory of Open Access Journals (Sweden)

    Jingyou Yu

    2015-10-01

    Full Text Available The interferon-induced transmembrane (IFITM proteins have been recently shown to restrict HIV-1 and other viruses. Here, we provide evidence that IFITM proteins, particularly IFITM2 and IFITM3, specifically antagonize the HIV-1 envelope glycoprotein (Env, thereby inhibiting viral infection. IFITM proteins interact with HIV-1 Env in viral producer cells, leading to impaired Env processing and virion incorporation. Notably, the level of IFITM incorporation into HIV-1 virions does not strictly correlate with the extent of inhibition. Prolonged passage of HIV-1 in IFITM-expressing T lymphocytes leads to emergence of Env mutants that overcome IFITM restriction. The ability of IFITMs to inhibit cell-to-cell infection can be extended to HIV-1 primary isolates, HIV-2 and SIVs; however, the extent of inhibition appears to be virus-strain dependent. Overall, our study uncovers a mechanism by which IFITM proteins specifically antagonize HIV-1 Env to restrict HIV-1 infection and provides insight into the specialized role of IFITMs in HIV infection.

  6. Formation of a unique cluster of G-quadruplex structures in the HIV-1 Nef coding region: implications for antiviral activity.

    Directory of Open Access Journals (Sweden)

    Rosalba Perrone

    Full Text Available G-quadruplexes are tetraplex structures of nucleic acids that can form in G-rich sequences. Their presence and functional role have been established in telomeres, oncogene promoters and coding regions of the human chromosome. In particular, they have been proposed to be directly involved in gene regulation at the level of transcription. Because the HIV-1 Nef protein is a fundamental factor for efficient viral replication, infectivity and pathogenesis in vitro and in vivo, we investigated G-quadruplex formation in the HIV-1 nef gene to assess the potential for viral inhibition through G-quadruplex stabilization. A comprehensive computational analysis of the nef coding region of available strains showed the presence of three conserved sequences that were uniquely clustered. Biophysical testing proved that G-quadruplex conformations were efficiently stabilized or induced by G-quadruplex ligands in all three sequences. Upon incubation with a G-quadruplex ligand, Nef expression was reduced in a reporter gene assay and Nef-dependent enhancement of HIV-1 infectivity was significantly repressed in an antiviral assay. These data constitute the first evidence of the possibility to regulate HIV-1 gene expression and infectivity through G-quadruplex targeting and therefore open a new avenue for viral treatment.

  7. HIV-1-negative female sex workers sustain high cervical IFNɛ, low immune activation, and low expression of HIV-1-required host genes.

    Science.gov (United States)

    Abdulhaqq, S A; Zorrilla, C; Kang, G; Yin, X; Tamayo, V; Seaton, K E; Joseph, J; Garced, S; Tomaras, G D; Linn, K A; Foulkes, A S; Azzoni, L; VerMilyea, M; Coutifaris, C; Kossenkov, A V; Showe, L; Kraiselburd, E N; Li, Q; Montaner, L J

    2016-07-01

    Sex workers practicing in high HIV endemic areas have been extensively targeted to test anti-HIV prophylactic strategies. We hypothesize that in women with high levels of genital exposure to semen changes in cervico-vaginal mucosal and/or systemic immune activation will contribute to a decreased susceptibility to HIV-1 infection. To address this question, we assessed sexual activity and immune activation status (in peripheral blood), as well as cellular infiltrates and gene expression in ectocervical mucosa biopsies in female sex workers (FSWs; n=50), as compared with control women (CG; n=32). FSWs had low-to-absent HIV-1-specific immune responses with significantly lower CD38 expression on circulating CD4(+) or CD8(+) T-cells (both: PHIV-1 integration and replication. A correlative relationship between semen exposure and elevated type-1 IFN expression in FSWs was also established. Overall, our data suggest that long-term condomless sex work can result in multiple changes within the cervico-vaginal compartment that would contribute to sustaining a lower susceptibility for HIV-1 infection in the absence of HIV-specific responses.

  8. Human immunodeficiency virus type-1 (HIV-1) genetic diversity and ...

    African Journals Online (AJOL)

    PROGMANAGER

    2013-04-24

    Apr 24, 2013 ... objective of this study was to determine the genetic diversity of HIV-1 and the prevalence of antiretroviral (ARV) ... individuals in resource limited settings. Key words: ... management of HIV infection even as antiretroviral (ARV).

  9. Correlation of immune activation with HIV-1 RNA levels assayed by real-time RT-PCR in HIV-1 Subtype C infected patients in Northern India

    Science.gov (United States)

    Agarwal, Atima; Sankaran, Sumathi; Vajpayee, Madhu; Sreenivas, V; Seth, Pradeep; Dandekar, Satya

    2014-01-01

    Background Assays with specificity and cost effectiveness are needed for the measurement of HIV-1 burden to monitor disease progression or response to anti-retroviral therapy (ART) in HIV-1 subtype C infected patients. Objectives The objective of this study was to develop and validate an affordable; one step Real-Time RT-PCR assay with high specificity and sensitivity to measure plasma HIV-1 loads in HIV-1 subtype C infected patients. Results We developed an RT-PCR assay to detect and quantitate plasma HIV-1 levels in HIV-1 subtype C infected patients. An inverse correlation between plasma viral loads (PVL) and CD4+ T-cell numbers was detected at all CDC stages. Significant correlations were found between CD8+ T-cell activation and PVL, as well as with the clinical and immunological status of the patients. Conclusions The RT-PCR assay provides a sensitive method to measure PVL in HIV-1 subtype C infected patients. Viral loads correlated with immune activation and can be used to monitor HIV care in India. PMID:17962068

  10. HIV-1, Methamphetamine and Astrocytes at Neuroinflammatory crossroads

    Directory of Open Access Journals (Sweden)

    Kathleen eBorgmann

    2015-10-01

    Full Text Available As a popular psychostimulant, methamphetamine (METH use leads to long-lasting, strong euphoric effects. While METH abuse is common in the general population, between 10-15% of human immunodeficiency virus-1 (HIV-1 patients report having abused METH. METH exacerbates the severity and onset of HIV-1-associated neurocognitive disorders (HAND through direct and indirect mechanisms. Repetitive METH use decreases adherence to antiretroviral drug regimens, increasing the likelihood of HIV-1 disease progression towards AIDS. METH exposure also directly affects both innate and adaptive immunity, altering lymphocyte number and activity, cytokine signaling, phagocytic function, and CNS infiltration through the blood brain barrier. Further, METH triggers the neuronal dopamine reward pathway and leads to altered neuronal activity and direct toxicity. Concurrently, METH and HIV-1 alter the neuroimmune balance and induce neuroinflammation. Neuroinflammation modulates a wide range of brain functions including neuronal signaling and activity, glial activation, viral infection, oxidative stress and excitotoxicity. Pathologically, glial activation is a hallmark of both HIV-1 and METH-associated neuroinflammation. Significant commonality exists in the neurotoxic mechanisms for both METH and HAND; however, the pathways dysregulated in astroglia during METH exposure are less clear. Thus alterations in astrocyte intracellular signaling pathways, gene expression and function during METH and HIV-1 comorbidity, neuroinflammation and HAND are carefully reviewed. Interventions targeting astrocytes in HAND and METH are presented as potential novel therapeutic approaches.

  11. Interferon-Inducible CD169/Siglec1 Attenuates Anti-HIV-1 Effects of Alpha Interferon

    Science.gov (United States)

    Akiyama, Hisashi; Ramirez, Nora-Guadalupe Pina; Gibson, Gregory; Kline, Christopher; Watkins, Simon; Ambrose, Zandrea

    2017-01-01

    ABSTRACT A hallmark of human immunodeficiency virus type 1 (HIV-1) infection in vivo is chronic immune activation concomitant with type I interferon (IFN) production. Although type I IFN induces an antiviral state in many cell types, HIV-1 can replicate in vivo via mechanisms that have remained unclear. We have recently identified a type I IFN-inducible protein, CD169, as the HIV-1 attachment factor on dendritic cells (DCs) that can mediate robust infection of CD4+ T cells in trans. Since CD169 expression on macrophages is also induced by type I IFN, we hypothesized that type I IFN-inducible CD169 could facilitate productive HIV-1 infection in myeloid cells in cis and CD4+ T cells in trans and thus offset antiviral effects of type I IFN. In support of this hypothesis, infection of HIV-1 or murine leukemia virus Env (MLV-Env)-pseudotyped HIV-1 particles was enhanced in IFN-α-treated THP-1 monocytoid cells, and this enhancement was primarily dependent on CD169-mediated enhancement at the virus entry step, a phenomenon phenocopied in HIV-1 infections of IFN-α-treated primary monocyte-derived macrophages (MDMs). Furthermore, expression of CD169, a marker of type I IFN-induced immune activation in vivo, was enhanced in lymph nodes from pigtailed macaques infected with simian immunodeficiency virus (SIV) carrying HIV-1 reverse transcriptase (RT-SHIV), compared to uninfected macaques, and interestingly, there was extensive colocalization of p27gag and CD169, suggesting productive infection of CD169+ myeloid cells in vivo. While cell-free HIV-1 infection of IFN-α-treated CD4+ T cells was robustly decreased, initiation of infection in trans via coculture with CD169+ IFN-α-treated DCs restored infection, suggesting that HIV-1 exploits CD169 in cis and in trans to attenuate a type I IFN-induced antiviral state. IMPORTANCE HIV-1 infection in humans causes immune activation characterized by elevated levels of proinflammatory cytokines, including type I interferons (IFN

  12. Profile of the HIV epidemic in Cape Verde: molecular epidemiology and drug resistance mutations among HIV-1 and HIV-2 infected patients from distinct islands of the archipelago.

    Science.gov (United States)

    de Pina-Araujo, Isabel Inês M; Guimarães, Monick L; Bello, Gonzalo; Vicente, Ana Carolina P; Morgado, Mariza G

    2014-01-01

    HIV-1 and HIV-2 have been detected in Cape Verde since 1987, but little is known regarding the genetic diversity of these viruses in this archipelago, located near the West African coast. In this study, we characterized the molecular epidemiology of HIV-1 and HIV-2 and described the occurrence of drug resistance mutations (DRM) among antiretroviral therapy naïve (ARTn) patients and patients under treatment (ARTexp) from different Cape Verde islands. Blood samples, socio-demographic and clinical-laboratory data were obtained from 221 HIV-positive individuals during 2010-2011. Phylogenetic and bootscan analyses of the pol region (1300 bp) were performed for viral subtyping. HIV-1 and HIV-2 DRM were evaluated for ARTn and ARTexp patients using the Stanford HIV Database and HIV-GRADE e.V. Algorithm Homepage, respectively. Among the 221 patients (169 [76.5%] HIV-1, 43 [19.5%] HIV-2 and 9 [4.1%] HIV-1/HIV-2 co-infections), 67% were female. The median ages were 34 (IQR = 1-75) and 47 (IQR = 12-84) for HIV-1 and HIV-2, respectively. HIV-1 infections were due to subtypes G (36.6%), CRF02_AG (30.6%), F1 (9.7%), URFs (10.4%), B (5.2%), CRF05_DF (3.0%), C (2.2%), CRF06_cpx (0.7%), CRF25_cpx (0.7%) and CRF49_cpx (0.7%), whereas all HIV-2 infections belonged to group A. Transmitted DRM (TDRM) was observed in 3.4% (2/58) of ARTn HIV-1-infected patients (1.7% NRTI, 1.7% NNRTI), but not among those with HIV-2. Among ARTexp patients, DRM was observed in 47.8% (33/69) of HIV-1 (37.7% NRTI, 37.7% NNRTI, 7.4% PI, 33.3% for two classes) and 17.6% (3/17) of HIV-2-infections (17.6% NRTI, 11.8% PI, 11.8% both). This study indicates that Cape Verde has a complex and unique HIV-1 molecular epidemiological scenario dominated by HIV-1 subtypes G, CRF02_AG and F1 and HIV-2 subtype A. The occurrence of TDRM and the relatively high level of DRM among treated patients are of concern. Continuous monitoring of patients on ART, including genotyping, are public policies to be implemented.

  13. Inhibition of cornifins and up-regulation of protease inhibitors in cervicovaginal lavage imparts resistance to heterosexual HIV transmission

    Directory of Open Access Journals (Sweden)

    Sushama Rokade

    2017-12-01

    Full Text Available HIV-exposed seronegative individuals (HESNs are persons who remain seronegative despite repeated exposure to HIV, suggesting an in vivo resistance mechanism to HIV. Elucidation of endogenous factors responsible for this phenomenon may aid in the development of new classes of microbicides and therapeutics. The genital mucosal secretions of both men and women are known to contain a spectrum of antimicrobials and immune mediators that may contribute to resistance against HIV-1. Existence of HIV serodiscordant couples is a testimony to mucosal factors in the genital tract that prevent sexual transmission of the virus. We attempted to map such mucosal factors in female genital secretions of the serodiscordant couples in comparison with HIV infected and healthy participants using quantitative proteomics. The cervico vaginal lavage (CVL samples were collected from three groups of study participants (HIV infected, n=30; Un-infected Controls, n=10; Serodiscordant, n=24. Abundant proteins, albumin and globulins were removed from the pooled samples using multiple affinity removal spin cartridge (Agilent to enhance the sensitivity of iTRAQ proteomics analysis. Initial analysis identified a total of 135 proteins and associated 497 peptide matches. Serodiscordant females showed significantly down regulated levels of Cornifin A, B and C, Neutrophil gelatinase, myeloperoxidase and eosinophil peroxidase. Cornifins are cross-linked envelope protein of keratinocytes and are upregulated during inflammation. Downregulation of oxidative stress inducing enzymes and cornifins suggests immune-quiescence in serodiscordant females. CVL of these women showed significantly upregulated levels of Mucin 5B, S100A7, Alpha-2-macroglobulin, Cystatin A (protease inhibitor, Lacto-transferrin, SLPI (anti-leukoproteinase inhibitor and SERPIN G1 (protease inhibitor.  Significantly elevated levels of Cystatin B and Elafin in the CVL of serodiscordant females were confirmed by ELISA

  14. Six Highly Conserved Targets of RNAi Revealed in HIV-1-Infected Patients from Russia Are Also Present in Many HIV-1 Strains Worldwide

    Directory of Open Access Journals (Sweden)

    Olga V. Kretova

    2017-09-01

    Full Text Available RNAi has been suggested for use in gene therapy of HIV/AIDS, but the main problem is that HIV-1 is highly variable and could escape attack from the small interfering RNAs (siRNAs due to even single nucleotide substitutions in the potential targets. To exhaustively check the variability in selected RNA targets of HIV-1, we used ultra-deep sequencing of six regions of HIV-1 from the plasma of two independent cohorts of patients from Russia. Six RNAi targets were found that are invariable in 82%–97% of viruses in both cohorts and are located inside the domains specifying reverse transcriptase (RT, integrase, vpu, gp120, and p17. The analysis of mutation frequencies and their characteristics inside the targets suggests a likely role for APOBEC3G (apolipoprotein B mRNA editing enzyme, catalytic polypeptide-like 3G, A3G in G-to-A mutations and a predominant effect of RT biases in the detected variability of the virus. The lowest frequency of mutations was detected in the central part of all six targets. We also discovered that the identical RNAi targets are present in many HIV-1 strains from many countries and from all continents. The data are important for both the understanding of the patterns of HIV-1 mutability and properties of RT and for the development of gene therapy approaches using RNAi for the treatment of HIV/AIDS. Keywords: HIV-1, RNAi targets, gene therapy, ultra-deep sequencing, conserved HIV-1 sequences

  15. Sero- and Molecular Epidemiology of HIV-1 in Papua Province, Indonesia

    Directory of Open Access Journals (Sweden)

    Muhammad Qushai Yunifiar M

    2017-11-01

    Full Text Available Background: human immunodeficiency virus (HIV infection and acquired immune deficiency syndrome (AIDS cause serious health problems and affect the Indonesian economy. Papua province has the highest prevalence of HIV infection in the country; however, epidemiological data are limited. Therefore, in order to reveal the current situation of HIV/AIDS in Papua province, sero- and molecular epidemiological studies of HIV were conducted. Methods: serological tests were conducted on 157 healthy individuals from the general population residing in Paniai, Papua. In addition, a molecular epidemiological study was then conducted on HIV type 1 (HIV-1 genes derived from infected individuals. Peripheral blood samples from HIV-1-positive individuals and 15 additionally enrolled, previously confirmed HIV-1-positive individuals were subjected to a genotypic analysis. Results: serological tests revealed that 2 out of 157 (1.27% healthy individuals were HIV-positive. In addition, HIV-1 subtyping revealed that subtype B and CRF01_AE were the major subtype and circulating recombinant form (CRF of HIV-1 prevalent in the region, while subtype A1 and a recombinant form including viral gene fragments of CRF01_AE and subtype B was also detected. In addition, HIV drug resistance-associated major mutations were detected in the reverse transcriptase gene derived from infected individual on antiretroviral therapy. Conclusion: these results provide important information for clearer understanding on the current situation of HIV/AIDS in Papua province in Indonesia.

  16. (Some) Cellular Mechanisms Influencing the Transcription of Human Endogenous Retrovirus, HERV-Fc1

    DEFF Research Database (Denmark)

    Laska, Magdalena Janina; Nissen, Kari Konstantin; Nexø, Bjørn Andersen

    2013-01-01

    DNA methylation and histone acetylation are epigenetic modifications that act as regulators of gene expression. DNA methylation is considered an important mechanism for silencing of retroelements in the mammalian genome. However, the methylation of human endogenous retroviruses (HERVs) is not well...... investigated. The aim of this study was to investigate the transcriptional potential of HERV-Fc1 proviral 5'LTR in more detail, and examined the specific influence of CpG methylation on this LTR in number of cell lines. Specifically, the role of demethylating chemicals e.g. 5-aza-2' deoxycytidine...... and Trichostatin-A, in inducing or reactivating expression of HERV-Fc1 specific sequences and the mechanisms were investigated. In our present study, 5-aza-dC is shown to be a powerful inducer of HERV-Fc1, and at the same time it strongly inhibits methylation of DNA. Treatment with this demethylating agent 5-aza...

  17. Molecular Mechanisms in Activation of Latent HIV-1

    NARCIS (Netherlands)

    H. Rafati (Haleh)

    2014-01-01

    markdownabstract__Abstract__ Finding a cure for the human immunodeficiency virus type 1 (HIV-1) is extremely challenging. Development of highly active anti-retroviral therapy (HAART), transformed HIV-1 infection from an acute syndrome into chronic disease. Although using HAART results in

  18. Identification of dual-tropic HIV-1 using evolved neural networks.

    Science.gov (United States)

    Fogel, Gary B; Lamers, Susanna L; Liu, Enoch S; Salemi, Marco; McGrath, Michael S

    2015-11-01

    Blocking the binding of the envelope HIV-1 protein to immune cells is a popular concept for development of anti-HIV therapeutics. R5 HIV-1 binds CCR5, X4 HIV-1 binds CXCR4, and dual-tropic HIV-1 can bind either coreceptor for cellular entry. R5 viruses are associated with early infection and over time can evolve to X4 viruses that are associated with immune failure. Dual-tropic HIV-1 is less studied; however, it represents functional antigenic intermediates during the transition of R5 to X4 viruses. Viral tropism is linked partly to the HIV-1 envelope V3 domain, where the amino acid sequence helps dictate the receptor a particular virus will target; however, using V3 sequence information to identify dual-tropic HIV-1 isolates has remained difficult. Our goal in this study was to elucidate features of dual-tropic HIV-1 isolates that assist in the biological understanding of dual-tropism and develop an approach for their detection. Over 1559 HIV-1 subtype B sequences with known tropisms were analyzed. Each sequence was represented by 73 structural, biochemical and regional features. These features were provided to an evolved neural network classifier and evaluated using balanced and unbalanced data sets. The study resolved R5X4 viruses from R5 with an accuracy of 81.8% and from X4 with an accuracy of 78.8%. The approach also identified a set of V3 features (hydrophobicity, structural and polarity) that are associated with tropism transitions. The ability to distinguish R5X4 isolates will improve computational tropism decisions for R5 vs. X4 and assist in HIV-1 research and drug development efforts. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  19. Incident HSV-2 Infections Are Common Among HIV-1-discordant Couples

    Science.gov (United States)

    Muiru, Anthony N.; Guthrie, Brandon L.; Bosire, Rose; Merkel, Michele; Liu, Amy Y.; Choi, Robert Y.; Lohman-Payne, Barbara; Gatuguta, Ann; Mackelprang, Romel D.; Kiarie, James N.; Farquhar, Carey

    2013-01-01

    Background. The synergy between herpes simplex virus type 2 (HSV-2) and human immunodeficiency virus type 1 (HIV-1) is well known, but lack of knowledge about the epidemiology of HSV-2 acquisition in HIV-1-discordant couples hampers development of HSV-2 prevention interventions that could reduce HIV-1 transmission. Methods. HIV-1-discordant couples were enrolled in Nairobi, Kenya, and followed for up to 2 years. HSV-2 status was determined using HerpeSelect HSV-2 ELISA. Correlates of prevalence and incidence were assessed. Results. Of 469 HIV-1-discordant couples, at baseline, 353 (75.3%) were affected by HSV-2, of which 189 (53.5%) were concordantly HSV-2 seropositive and 164 (46.5%) were HSV-2-discordant. Prevalence was lowest among HIV-1-uninfected men (39.9%) compared to HIV-1-infected women (64.8%), HIV-1-infected men (66.7%), and HIV-1-uninfected women (68.5%). During follow-up, HSV-2 seroincidence was 14.9 per 100 person-years. Incidence was 1.6-fold higher among females compared to males (95% confidence interval [CI], 1.00–2.48) and 2.5-fold higher in HIV-1-infected compared to uninfected women (95% CI, 1.12–5.74). At least 30% of incident HSV-2 infections originated from an outside partner. Conclusions. The high HSV-2 prevalence and incidence in HIV-1-discordant couples in sub-Saharan Africa suggest HSV-2 treatment and prevention could be an effective targeted strategy to reduce HSV-2 and HIV-1 transmission in this high-risk population. PMID:23840044

  20. Kaposi's-sarcoma-associated-herpesvirus-activated dendritic cells promote HIV-1 trans-infection and suppress CD4+ T cell proliferation

    International Nuclear Information System (INIS)

    Liu, Wan; Qin, Yan; Bai, Lei; Lan, Ke; Wang, Jian-Hua

    2013-01-01

    Infection of Kaposi's sarcoma-associated herpesvirus (KSHV) is commonly occurred in AIDS patients. KSHV and HIV-1 act cooperatively in regulating infection with each other and in human carcinogenesis. Dendritic cells (DCs), as the pivotal cells in host immunity, may be modulated by both viruses, for immunoevasion and dissemination, therefore, the interaction between DCs and each virus has been a prior focus for pathogenesis elucidation. Here, we assessed the potential effect of KSHV on DC–HIV-1 interaction. We found that KSHV stimulation could promote maturation of monocyte-derived DCs (MDDCs) and impaired the ability of MDDCs to drive proliferation of resting CD4 + T cells, demonstrating the immunosuppression induced by KSHV. More importantly, KSHV-stimulated MDDCs could capture more HIV-1 and efficiently transferred these infectious viruses to Hut/CCR5 T cell line. Our results reveal the novel modulation of DC-mediated HIV-1 dissemination by KSHV, and highlight the importance of studying DC–HIV-1 interaction to elucidate HIV/AIDS pathogenesis. - Highlights: ► KSHV impaired the ability of MDDCs to drive proliferation of resting CD4 + T cells. ► KSHV stimulation matured MDDCs and enhanced HIV-1 endocytosis. ► KSHV stimulated MDDCs increased ICAM-1 expression and tighten contact with T cells. ► KSHV-stimulated MDDCs promoted HIV-1 trans-infection of CD4 + T cells

  1. Analysis of Select Herpes Simplex Virus 1 (HSV-1) Proteins for Restriction of Human Immunodeficiency Virus Type 1 (HIV-1): HSV-1 gM Protein Potently Restricts HIV-1 by Preventing Intracellular Transport and Processing of Env gp160.

    Science.gov (United States)

    Polpitiya Arachchige, Sachith; Henke, Wyatt; Pramanik, Ankita; Kalamvoki, Maria; Stephens, Edward B

    2018-01-15

    Virus-encoded proteins that impair or shut down specific host cell functions during replication can be used as probes to identify potential proteins/pathways used in the replication of viruses from other families. We screened nine proteins from herpes simplex virus 1 (HSV-1) for the ability to enhance or restrict human immunodeficiency virus type 1 (HIV-1) replication. We show that several HSV-1 proteins (glycoprotein M [gM], US3, and UL24) potently restricted the replication of HIV-1. Unlike UL24 and US3, which reduced viral protein synthesis, we observed that gM restriction of HIV-1 occurred through interference with the processing and transport of gp160, resulting in a significantly reduced level of mature gp120/gp41 released from cells. Finally, we show that an HSV-1 gM mutant lacking the majority of the C-terminal domain (HA-gM[Δ345-473]) restricted neither gp160 processing nor the release of infectious virus. These studies identify proteins from heterologous viruses that can restrict viruses through novel pathways. IMPORTANCE HIV-1 infection of humans results in AIDS, characterized by the loss of CD4 + T cells and increased susceptibility to opportunistic infections. Both HIV-1 and HSV-1 can infect astrocytes and microglia of the central nervous system (CNS). Thus, the identification of HSV-1 proteins that directly restrict HIV-1 or interfere with pathways required for HIV-1 replication could lead to novel antiretroviral strategies. The results of this study show that select viral proteins from HSV-1 can potently restrict HIV-1. Further, our results indicate that the gM protein of HSV-1 restricts HIV-1 through a novel pathway by interfering with the processing of gp160 and its incorporation into virus maturing from the cell. Copyright © 2018 American Society for Microbiology.

  2. Regional gene expression of LOX-1, VCAM-1, and ICAM-1 in aorta of HIV-1 transgenic rats

    DEFF Research Database (Denmark)

    Hag, Anne Mette Fisker; Kristoffersen, Ulrik Sloth; Pedersen, Sune Folke

    2009-01-01

    endpoints, studies in animal models could be attractive alternatives. METHODOLOGY/PRINCIPAL FINDINGS: We evaluated gene expression of lectin-like oxidized-low-density-lipoprotein receptor-1 (LOX-1), vascular cell adhesion molecule-1 (VCAM-1), and intercellular adhesion molecule-1 (ICAM-1) in HIV-1...... transgenic (HIV-1Tg) rats; these genes are all thought to play important roles in early atherogenesis. Furthermore, the plasma level of sICAM-1 was measured. We found that gene expressions of LOX-1 and VCAM-1 were higher in the aortic arch of HIV-1Tg rats compared to controls. Also, the level of sICAM-1......-infection per se may cause atherosclerosis. This transgenic rat model may be a very promising model for further studies of the pathophysiology behind HIV-associated cardiovascular disease....

  3. Striking HIV-1 Entry by Targeting HIV-1 gp41. But, Where Should We Target?

    Directory of Open Access Journals (Sweden)

    Cátia Teixeira

    Full Text Available HIV-1 gp41 facilitates the viral fusion through a conformational switch involving the association of three C-terminal helices along the conserved hydrophobic grooves of three N-terminal helices coiled-coil. The control of these structural rearrangements is thought to be central to HIV-1 entry and, therefore, different strategies of intervention are being developed. Herewith, we describe a procedure to simulate the folding of an HIV-1 gp41 simplified model. This procedure is based on the construction of plausible conformational pathways, which describe protein transition between non-fusogenic and fusogenic conformations. The calculation of the paths started with 100 molecular dynamics simulations of the non-fusogenic conformation, which were found to converge to different intermediate states. Those presenting defined criteria were selected for separate targeted molecular dynamics simulations, subjected to a force constant imposing a movement towards the gp41 fusogenic conformation. Despite significant diversity, a preferred sequence of events emerged when the simulations were analyzed in terms of the formation, breakage and evolution of the contacts. We pointed out 29 residues as the most relevant for the movement of gp41; also, 2696 possible interactions were reduced to only 48 major interactions, which reveals the efficiency of the method. The analysis of the evolution of the main interactions lead to the detection of four main behaviors for those contacts: stable, increasing, decreasing and repulsive interactions. Altogether, these results suggest a specific small cavity of the HIV-1 gp41 hydrophobic groove as the preferred target to small molecules.

  4. Necroptosis takes place in human immunodeficiency virus type-1 (HIV-1-infected CD4+ T lymphocytes.

    Directory of Open Access Journals (Sweden)

    Ting Pan

    Full Text Available Human immunodeficiency virus type 1 (HIV-1 infection is characterized by progressive depletion of CD4+ T lymphocytes and dysfunction of the immune system. The numbers of CD4+ T lymphocytes in the human body are maintained constantly by homeostatic mechanisms that failed during HIV-1 infection, resulting in progressive loss of CD4+ T cells mainly via apoptosis. Recently, a non-apoptotic form of necrotic programmed cell death, named necroptosis, has been investigated in many biological and pathological processes. We then determine whether HIV-1-infected cells also undergo necroptosis. In this report, we demonstrate that HIV-1 not only induces apoptosis, but also mediates necroptosis in the infected primary CD4+ T lymphocytes and CD4+ T-cell lines. Necroptosis-dependent cytopathic effects are significantly increased in HIV-1-infected Jurkat cells that is lack of Fas-associated protein-containing death domain (FADD, indicating that necroptosis occurs as an alternative cell death mechanism in the absence of apoptosis. Unlike apoptosis, necroptosis mainly occurs in HIV-infected cells and spares bystander damage. Treatment with necrostatin-1(Nec-1, a RIP1 inhibitor that specifically blocks the necroptosis pathway, potently restrains HIV-1-induced cytopathic effect and interestingly, inhibits the formation of HIV-induced syncytia in CD4+ T-cell lines. This suggests that syncytia formation is mediated, at least partially, by necroptosis-related processes. Furthermore, we also found that the HIV-1 infection-augmented tumor necrosis factor-alpha (TNF-α plays a key role in inducing necroptosis and HIV-1 Envelope and Tat proteins function as its co-factors. Taken together,necroptosis can function as an alternative cell death pathway in lieu of apoptosis during HIV-1 infection, thereby also contributing to HIV-1-induced cytopathic effects. Our results reveal that in addition to apoptosis, necroptosis also plays an important role in HIV-1-induced pathogenesis.

  5. Schistosomiasis and HIV-1 infection in rural Zimbabwe

    DEFF Research Database (Denmark)

    Kallestrup, Per; Zinyama, Rutendo; Gomo, Exnevia

    2005-01-01

    Stunted development and reduced fecundity of Schistosoma parasites in immunodeficient mice and the impaired ability of human immunodeficiency virus 1 (HIV-1)-infected humans to excrete schistosome eggs have been described. This study explores the effect that HIV-1-associated immunodeficiency has...

  6. Vitamin D deficiency among HIV type 1-infected individuals in the Netherlands: effects of antiretroviral therapy.

    NARCIS (Netherlands)

    Bout-van den Beukel, C.J.P. van den; Fievez, L.; Michels, M.; Sweep, F.C.; Hermus, A.R.M.M.; Bosch, M.E.; Burger, D.M.; Bravenboer, B.; Koopmans †, P.P.; Ven, A.J.A.M. van der

    2008-01-01

    Vitamin D regulates bone metabolism but has also immunoregulatory properties. In HIV-infected patients bone disorders are increasingly observed. Furthermore, low 1,25(OH)(2)D(3) levels have been associated with low CD4(+) counts, immunological hyperactivity, and AIDS progression rates. Few studies

  7. Mortality Attributable to Smoking Among HIV-1-Infected Individuals

    DEFF Research Database (Denmark)

    Helleberg, Marie; Afzal, Shoaib; Kronborg, Gitte

    2013-01-01

    and with HIV among current and nonsmoking individuals from a population-based, nationwide HIV cohort and a cohort of matched HIV-negative individuals.Results. A total of 2921 HIV patients and 10 642 controls were followed for 14 281 and 45 122 person-years, respectively. All-cause and non......-AIDS-related mortality was substantially increased among smoking compared to nonsmoking HIV patients (MRR, 4.4 [95% confidence interval {CI}, 3.0-6.7] and 5.3 [95% CI, 3.2-8.8], respectively). Excess MR per 1000 person-years among current vs nonsmokers was 17.6 (95% CI, 13.3-21.9) for HIV patients and 4.8 (95% CI, 3.......2-6.4) for controls. A 35-year-old HIV patient had a median life expectancy of 62.6 years (95% CI, 59.9-64.6) for smokers and 78.4 years (95% CI, 70.8-84.0) for nonsmokers; the numbers of life-years lost in association with smoking and HIV were 12.3 (95% CI, 8.1-16.4) and 5.1 (95% CI, 1.6-8.5). The population...

  8. Phylodynamics of the HIV-1 epidemic in Cuba.

    Science.gov (United States)

    Delatorre, Edson; Bello, Gonzalo

    2013-01-01

    Previous studies have shown that the HIV-1 epidemic in Cuba displayed a complex molecular epidemiologic profile with circulation of several subtypes and circulating recombinant forms (CRF); but the evolutionary and population history of those viral variants remains unknown. HIV-1 pol sequences of the most prevalent Cuban lineages (subtypes B, C and G, CRF18_cpx, CRF19_cpx, and CRFs20/23/24_BG) isolated between 1999 and 2011 were analyzed. Maximum-likelihood analyses revealed multiple introductions of subtype B (n≥66), subtype C (n≥10), subtype G (n≥8) and CRF18_cpx (n≥2) viruses in Cuba. The bulk of HIV-1 infections in this country, however, was caused by dissemination of a few founder strains probably introduced from North America/Europe (clades B(CU-I) and B(CU-II)), east Africa (clade C(CU-I)) and central Africa (clades G(CU), CRF18(CU) and CRF19(CU)), or locally generated (clades CRFs20/23/24_BG). Bayesian-coalescent analyses show that the major HIV-1 founder strains were introduced into Cuba during 1985-1995; whereas the CRFs_BG strains emerged in the second half of the 1990s. Most HIV-1 Cuban clades appear to have experienced an initial period of fast exponential spread during the 1990s and early 2000s, followed by a more recent decline in growth rate. The median initial growth rate of HIV-1 Cuban clades ranged from 0.4 year⁻¹ to 1.6 year⁻¹. Thus, the HIV-1 epidemic in Cuba has been a result of the successful introduction of a few viral strains that began to circulate at a rather late time of the AIDS pandemic, but then were rapidly disseminated through local transmission networks.

  9. Imperatorin inhibits HIV-1 replication through an Sp1-dependent pathway.

    Science.gov (United States)

    Sancho, Rocío; Márquez, Nieves; Gómez-Gonzalo, Marta; Calzado, Marco A; Bettoni, Giorgio; Coiras, Maria Teresa; Alcamí, José; López-Cabrera, Manuel; Appendino, Giovanni; Muñoz, Eduardo

    2004-09-03

    Coumarins and structurally related compounds have been recently shown to present anti-human immunodeficiency virus, type 1 (HIV-1) activity. Among them, the dietary furanocoumarin imperatorin is present in citrus fruits, in culinary herbs, and in some medicinal plants. In this study we report that imperatorin inhibits either vesicular stomatitis virus-pseudotyped or gp160-enveloped recombinant HIV-1 infection in several T cell lines and in HeLa cells. These recombinant viruses express luciferase as a marker of viral replication. Imperatorin did not inhibit the reverse transcription nor the integration steps in the viral cell cycle. Using several 5' long terminal repeat-HIV-1 constructs where critical response elements were either deleted or mutated, we found that the transcription factor Sp1 is critical for the inhibitory activity of imperatorin induced by both phorbol 12-myristate 13-acetate and HIV-1 Tat. Moreover in transient transfections imperatorin specifically inhibited phorbol 12-myristate 13-acetate-induced transcriptional activity of the Gal4-Sp1 fusion protein. Since Sp1 is also implicated in cell cycle progression we further studied the effect of imperatorin on cyclin D1 gene transcription and protein expression and in HeLa cell cycle progression. We found that imperatorin strongly inhibited cyclin D1 expression and arrested the cells at the G(1) phase of the cell cycle. These results highlight the potential of Sp1 transcription factor as a target for natural anti-HIV-1 compounds such as furanocoumarins that might have a potential therapeutic role in the management of AIDS.

  10. Inefficient HIV-1 trans infection of CD4+ T cells by macrophages from HIV-1 nonprogressors is associated with altered membrane cholesterol and DC-SIGN.

    Science.gov (United States)

    DeLucia, Diana C; Rinaldo, Charles R; Rappocciolo, Giovanna

    2018-04-11

    Professional antigen presenting cells (APC: myeloid dendritic cells (DC) and macrophages (MΦ); B lymphocytes) mediate highly efficient HIV-1 infection of CD4 + T cells, termed trans infection, that could contribute to HIV-1 pathogenesis. We have previously shown that lower cholesterol content in DC and B lymphocytes is associated with a lack of HIV-1 trans infection in HIV-1 infected nonprogressors (NP). Here we assessed whether HIV-1 trans infection mediated by another major APC, MΦ, is deficient in NP due to altered cholesterol metabolism. When comparing healthy HIV-1 seronegatives (SN), rapid progressors (PR), and NP, we found that monocyte-derived MΦ from NP did not mediate HIV-1 trans infection of autologous CD4 + T cells, in contrast to efficient trans infection mediated by SN and PR MΦ. MΦ trans infection efficiency was directly associated with the number of DC-specific intercellular adhesion molecule-3-grabbing non-integrin (DC-SIGN)-expressing MΦ. Significantly fewer NP MΦ expressed DC-SIGN. Unesterified (free) cholesterol in MΦ cell membranes and lipid rafting was significantly lower in NP than PR, as well as virus internalization in early endosomes. Furthermore, simvastatin (SIMV), decreased the subpopulation of DC-SIGN + MΦ, as well as MΦ cis and trans infection. Notably, SIMV decreased cell membrane cholesterol and led to lipid raft dissociation, effectively mimicking the incompetent APC trans infection environment characteristic of NP. Our data support that DC-SIGN and membrane cholesterol are central to MΦ trans infection, and a lack of these limits HIV-1 disease progression. Targeting the ability of MΦ to drive HIV-1 dissemination in trans could enhance HIV-1 therapeutic strategies. IMPORTANCE Despite the success of combination anti-retroviral therapy, neither a vaccine nor a cure for HIV infection has been developed, demonstrating a need for novel prophylactic and therapeutic strategies. Here we show that efficiency of macrophage (M

  11. Alemtuzumab-induced elimination of HIV-1-infected immune cells.

    Science.gov (United States)

    Ruxrungtham, Kiat; Sirivichayakul, Sunee; Buranapraditkun, Supranee; Krause, Werner

    2016-01-01

    Currently, there is no drug known that is able to eradicate either HIV or HIV-infected host cells. The effectiveness of all available treatments is based on the prevention of viral replication. We investigated whether the monoclonal, CD52 receptor-targeting antibody, alemtuzumab, which is currently approved for the treatment of multiple sclerosis, is able to eliminate HIV-infected immune cells. In blood samples from healthy donors and from HIV-1-infected subjects who were either treatment-naïve or resistant to HAART, we studied whether the CD52 expression on T cells and their subsets (CD3, CD4, CD8), B cells (CD19), dendritic cells (CD123) and monocytes (CD11c) is retained in HIV-1 infection and whether alemtuzumab is able to eradicate infected cells, using four-colour flow cytometry. We found that CD52 expression on immune cells is retained in HIV-1 infection regardless of CD4 cell count, viral load and treatment status, and is amenable to alemtuzumab-induced depletion. For the first time it could be shown in vitro that HIV-1-infected immune cells can be eliminated by using the monoclonal antibody alemtuzumab.

  12. Purinergic Receptors: Key Mediators of HIV-1 infection and inflammation

    Directory of Open Access Journals (Sweden)

    Talia H Swartz

    2015-11-01

    Full Text Available Human immunodeficiency virus (HIV-1 causes a chronic infection that afflicts more than 38 million individuals worldwide. While the infection can be suppressed with potent anti-retroviral therapies, individuals infected with HIV have elevated levels of inflammation as indicated by increased T cell activation, soluble biomarkers, and associated morbidity and mortality. A single mechanism linking HIV pathogenesis to this inflammation has yet to be identified. Purinergic receptors are known to mediate inflammation and have been shown to be required for HIV-1 infection at the level of HIV-1 membrane fusion. Here we review the literature on the role of purinergic receptors in HIV-1 infection and associated inflammation and describe a role for these receptors as potential therapeutic targets.

  13. Re-testing and misclassification of HIV-2 and HIV-1&2 dually reactive patients among the HIV-2 cohort of The West African Database to evaluate AIDS collaboration

    Science.gov (United States)

    Tchounga, Boris K; Inwoley, Andre; Coffie, Patrick A; Minta, Daouda; Messou, Eugene; Bado, Guillaume; Minga, Albert; Hawerlander, Denise; Kane, Coumba; Eholie, Serge P; Dabis, François; Ekouevi, Didier K

    2014-01-01

    Introduction West Africa is characterized by the circulation of HIV-1 and HIV-2. The laboratory diagnosis of these two infections as well as the choice of a first-line antiretroviral therapy (ART) is challenging, considering the limited access to second-line regimens. This study aimed at confirming the classification of HIV-2 and HIV-1&2 dually reactive patients followed up in the HIV-2 cohort of the West African Database to evaluate AIDS collaboration. Method A cross-sectional survey was conducted from March to December 2012 in Burkina Faso, Côte d’Ivoire and Mali among patients classified as HIV-2 or HIV-1&2 dually reactive according to the national HIV testing algorithms. A 5-ml blood sample was collected from each patient and tested in a single reference laboratory in Côte d’Ivoire (CeDReS, Abidjan) with two immuno-enzymatic tests: ImmunoCombII® (HIV-1&2 ImmunoComb BiSpot – Alere) and an in-house ELISA test, approved by the French National AIDS and hepatitis Research Agency (ANRS). Results A total of 547 patients were included; 57% of them were initially classified as HIV-2 and 43% as HIV-1&2 dually reactive. Half of the patients had CD4≥500 cells/mm3 and 68.6% were on ART. Of the 312 patients initially classified as HIV-2, 267 (85.7%) were confirmed as HIV-2 with ImmunoCombII® and in-house ELISA while 16 (5.1%) and 9 (2.9%) were reclassified as HIV-1 and HIV-1&2, respectively (Kappa=0.69; p<0.001). Among the 235 patients initially classified as HIV-1&2 dually reactive, only 54 (23.0%) were confirmed as dually reactive with ImmunoCombII® and in-house ELISA, while 103 (43.8%) and 33 (14.0%) were reclassified as HIV-1 and HIV-2 mono-infected, respectively (kappa= 0.70; p<0.001). Overall, 300 samples (54.8%) were concordantly classified as HIV-2, 63 (11.5%) as HIV-1&2 dually reactive and 119 (21.8%) as HIV-1 (kappa=0.79; p<0.001). The two tests gave discordant results for 65 samples (11.9%). Conclusions Patients with HIV-2 mono-infection are correctly

  14. Novel Latency Reversal Agents for HIV-1 Cure.

    Science.gov (United States)

    Spivak, Adam M; Planelles, Vicente

    2018-01-29

    Antiretroviral therapy (ART) has rendered HIV-1 infection a treatable illness; however, ART is not curative owing to the persistence of replication-competent, latent proviruses in long-lived resting T cells. Strategies that target these latently infected cells and allow immune recognition and clearance of this reservoir will be necessary to eradicate HIV-1 in infected individuals. This review describes current pharmacologic approaches to reactivate the latent reservoir so that infected cells can be recognized and targeted, with the ultimate goal of achieving an HIV-1 cure.

  15. Acceleration of Age-Associated Methylation Patterns in HIV-1-Infected Adults

    Science.gov (United States)

    Sehl, Mary; Sinsheimer, Janet S.; Hultin, Patricia M.; Hultin, Lance E.; Quach, Austin; Martínez-Maza, Otoniel; Horvath, Steve; Vilain, Eric; Jamieson, Beth D.

    2015-01-01

    Patients with treated HIV-1-infection experience earlier occurrence of aging-associated diseases, raising speculation that HIV-1-infection, or antiretroviral treatment, may accelerate aging. We recently described an age-related co-methylation module comprised of hundreds of CpGs; however, it is unknown whether aging and HIV-1-infection exert negative health effects through similar, or disparate, mechanisms. We investigated whether HIV-1-infection would induce age-associated methylation changes. We evaluated DNA methylation levels at >450,000 CpG sites in peripheral blood mononuclear cells (PBMC) of young (20-35) and older (36-56) adults in two separate groups of participants. Each age group for each data set consisted of 12 HIV-1-infected and 12 age-matched HIV-1-uninfected samples for a total of 96 samples. The effects of age and HIV-1 infection on methylation at each CpG revealed a strong correlation of 0.49, pmodules; module 3 (ME3) was significantly correlated with age (cor=0.70) and HIV-1 status (cor=0.31). Older HIV-1+ individuals had a greater number of hypermethylated CpGs across ME3 (p=0.015). In a multivariate model, ME3 was significantly associated with age and HIV status (Data set 1: βage= 0.007088, p=2.08 x 10-9; βHIV= 0.099574, p=0.0011; Data set 2: βage= 0.008762, p=1.27x 10-5; βHIV= 0.128649, p= 0.0001). Using this model, we estimate that HIV-1 infection accelerates age-related methylation by approximately 13.7 years in data set 1 and 14.7 years in data set 2. The genes related to CpGs in ME3 are enriched for polycomb group target genes known to be involved in cell renewal and aging. The overlap between ME3 and an aging methylation module found in solid tissues is also highly significant (Fisher-exact p=5.6 x 10-6, odds ratio=1.91). These data demonstrate that HIV-1 infection is associated with methylation patterns that are similar to age-associated patterns and suggest that general aging and HIV-1 related aging work through some common cellular

  16. Discovery of natural mouse serum derived HIV-1 entry inhibitor(s).

    Science.gov (United States)

    Wei, M; Chen, Y; Xi, J; Ru, S; Ji, M; Zhang, D; Fang, Q; Tang, B

    Among rationally designed human immunodeficiency virus 1 (HIV-1) inhibitors, diverse natural factors have showed as potent anti-HIV activity in human blood. We have discovered that the boiled supernatant of healthy mouse serum could suppress HIV-1 entry, and exhibited reduced inhibitory activity after trypsin digestion. Further analysis demonstrated that only the fraction containing 10-25 K proteins could inhibit HIV-1 mediated cell-cell fusion. These results suggest that the 10-25 K protein(s) is novel natural HIV-1 entry inhibitor(s). Our findings provide important information about novel natural HIV entry inhibitors in mouse serum.

  17. THE PREVALENCE OF HUMAN IMMUNODEFIENCY VIRUS-1 (HIV-1 SUBTYPES AND TRANSMISSION METHOD AMONG HIV/AIDS INFECTION PATIENT IN TULUNGAGUNG, EAST JAVA INDONESIA

    Directory of Open Access Journals (Sweden)

    Achmad Ardianto

    2015-05-01

    Full Text Available The rapid epidemic growth of HIV is continuing in Indonesia. There are some factors which have influenced the spreading of this epidemic in Indonesia, such as the poor awareness to avoid unsafe free sex attitude and the sharing of needles and syringes among intravenous drug users (IDUs. The sexual transmission of HIV has also apparently increased in Tulungagung. Commercial sex workers play a significant role in the spread of HIV in Tulungagung. People in Tulungagung have worked at other countries as Indonesian migrants. This condition can cause the increase number of HIV-1 case and the possibility of genetic variation (subtype HIV-1 in Tulungagung. This research is aimed to analyze the subtype and to determine estimation of transmission mode on infected patient of HIV-1 and AIDS who came to Seruni clinic Dr. Iskak hospital in Tulungagung. 40 HIV?AIDSpatients were interviewed to determine the subtype and the transmission mode. The results showed that 14 of 40 plasma samples (35% were successfully to amplified and sequenced. OverallCRF01-AE wereidentified as predominant subtype among HIV/AIDS patients in Tulungagung. Based on individual information, 31 of 40 subjects (77% were heterosexual transmission.

  18. Similarities and differences in the nucleic acid chaperone activity of HIV-2 and HIV-1 nucleocapsid proteins in vitro.

    Science.gov (United States)

    Pachulska-Wieczorek, Katarzyna; Stefaniak, Agnieszka K; Purzycka, Katarzyna J

    2014-07-03

    The nucleocapsid domain of Gag and mature nucleocapsid protein (NC) act as nucleic acid chaperones and facilitate folding of nucleic acids at critical steps of retroviral replication cycle. The basic N-terminus of HIV-1 NC protein was shown most important for the chaperone activity. The HIV-2 NC (NCp8) and HIV-1 NC (NCp7) proteins possess two highly conserved zinc fingers, flanked by basic residues. However, the NCp8 N-terminal domain is significantly shorter and contains less positively charged residues. This study characterizes previously unknown, nucleic acid chaperone activity of the HIV-2 NC protein. We have comparatively investigated the in vitro nucleic acid chaperone properties of the HIV-2 and HIV-1 NC proteins. Using substrates derived from the HIV-1 and HIV-2 genomes, we determined the ability of both proteins to chaperone nucleic acid aggregation, annealing and strand exchange in duplex structures. Both NC proteins displayed comparable, high annealing activity of HIV-1 TAR DNA and its complementary nucleic acid. Interesting differences between the two NC proteins were discovered when longer HIV substrates, particularly those derived from the HIV-2 genome, were used in chaperone assays. In contrast to NCp7, NCp8 weakly facilitates annealing of HIV-2 TAR RNA to its complementary TAR (-) DNA. NCp8 is also unable to efficiently stimulate tRNALys3 annealing to its respective HIV-2 PBS motif. Using truncated NCp8 peptide, we demonstrated that despite the fact that the N-terminus of NCp8 differs from that of NCp7, this domain is essential for NCp8 activity. Our data demonstrate that the HIV-2 NC protein displays reduced nucleic acid chaperone activity compared to that of HIV-1 NC. We found that NCp8 activity is limited by substrate length and stability to a greater degree than that of NCp7. This is especially interesting in light of the fact that the HIV-2 5'UTR is more structured than that of HIV-1. The reduced chaperone activity observed with NCp8 may

  19. Alterations in cholesterol metabolism restrict HIV-1 trans infection in nonprogressors.

    Science.gov (United States)

    Rappocciolo, Giovanna; Jais, Mariel; Piazza, Paolo; Reinhart, Todd A; Berendam, Stella J; Garcia-Exposito, Laura; Gupta, Phalguni; Rinaldo, Charles R

    2014-04-29

    ABSTRACT HIV-1-infected nonprogressors (NP) inhibit disease progression for years without antiretroviral therapy. Defining the mechanisms for this resistance to disease progression could be important in determining strategies for controlling HIV-1 infection. Here we show that two types of professional antigen-presenting cells (APC), i.e., dendritic cells (DC) and B lymphocytes, from NP lacked the ability to mediate HIV-1 trans infection of CD4(+) T cells. In contrast, APC from HIV-1-infected progressors (PR) and HIV-1-seronegative donors (SN) were highly effective in mediating HIV-1 trans infection. Direct cis infection of T cells with HIV-1 was comparably efficient among NP, PR, and SN. Lack of HIV-1 trans infection in NP was linked to lower cholesterol levels and an increase in the levels of the reverse cholesterol transporter ABCA1 (ATP-binding cassette transporter A1) in APC but not in T cells. Moreover, trans infection mediated by APC from NP could be restored by reconstitution of cholesterol and by inhibiting ABCA1 by mRNA interference. Importantly, this appears to be an inherited trait, as it was evident in APC obtained from NP prior to their primary HIV-1 infection. The present study demonstrates a new mechanism wherein enhanced lipid metabolism in APC results in remarkable control of HIV-1 trans infection that directly relates to lack of HIV-1 disease progression. IMPORTANCE HIV-1 can be captured by antigen-presenting cells (APC) such as dendritic cells and transferred to CD4 helper T cells, which results in greatly enhanced viral replication by a mechanism termed trans infection. A small percentage of HIV-1-infected persons are able to control disease progression for many years without antiretroviral therapy. In our study, we linked this lack of disease progression to a profound inability of APC from these individuals to trans infect T cells. This effect was due to altered lipid metabolism in their APC, which appears to be an inherited trait. These

  20. Rapid Antiretroviral Therapy Initiation for Women in an HIV-1 Prevention Clinical Trial Experiencing Primary HIV-1 Infection during Pregnancy or Breastfeeding.

    Science.gov (United States)

    Morrison, Susan; John-Stewart, Grace; Egessa, John J; Mubezi, Sezi; Kusemererwa, Sylvia; Bii, Dennis K; Bulya, Nulu; Mugume, Francis; Campbell, James D; Wangisi, Jonathan; Bukusi, Elizabeth A; Celum, Connie; Baeten, Jared M

    2015-01-01

    During an HIV-1 prevention clinical trial in East Africa, we observed 16 cases of primary HIV-1 infection in women coincident with pregnancy or breastfeeding. Nine of eleven pregnant women initiated rapid combination antiretroviral therapy (ART), despite having CD4 counts exceeding national criteria for ART initiation; breastfeeding women initiated ART or replacement feeding. Rapid ART initiation during primary HIV-1 infection during pregnancy and breastfeeding is feasible in this setting.

  1. Rapid Antiretroviral Therapy Initiation for Women in an HIV-1 Prevention Clinical Trial Experiencing Primary HIV-1 Infection during Pregnancy or Breastfeeding.

    Directory of Open Access Journals (Sweden)

    Susan Morrison

    Full Text Available During an HIV-1 prevention clinical trial in East Africa, we observed 16 cases of primary HIV-1 infection in women coincident with pregnancy or breastfeeding. Nine of eleven pregnant women initiated rapid combination antiretroviral therapy (ART, despite having CD4 counts exceeding national criteria for ART initiation; breastfeeding women initiated ART or replacement feeding. Rapid ART initiation during primary HIV-1 infection during pregnancy and breastfeeding is feasible in this setting.

  2. Performance comparison of the 4th generation Bio-Rad Laboratories GS HIV Combo Ag/Ab EIA on the EVOLIS™ automated system versus Abbott ARCHITECT HIV Ag/Ab Combo, Ortho Anti-HIV 1+2 EIA on Vitros ECi and Siemens HIV-1/O/2 enhanced on Advia Centaur.

    Science.gov (United States)

    Mitchell, Elizabeth O; Stewart, Greg; Bajzik, Olivier; Ferret, Mathieu; Bentsen, Christopher; Shriver, M Kathleen

    2013-12-01

    A multisite study was conducted to evaluate the performance of the Bio-Rad 4th generation GS HIV Combo Ag/Ab EIA versus Abbott 4th generation ARCHITECT HIV Ag/Ab Combo. The performance of two 3rd generation EIAs, Ortho Diagnostics Anti-HIV 1+2 EIA and Siemens HIV 1/O/2 was also evaluated. Study objective was comparison of analytical HIV-1 p24 antigen detection, sensitivity in HIV-1 seroconversion panels, specificity in blood donors and two HIV false reactive panels. Analytical sensitivity was evaluated with International HIV-1 p24 antigen standards, the AFFSAPS (pg/mL) and WHO 90/636 (IU/mL) standards; sensitivity in acute infection was compared on 55 seroconversion samples, and specificity was evaluated on 1000 negative blood donors and two false reactive panels. GS HIV Combo Ag/Ab demonstrated better analytical HIV antigen sensitivity compared to ARCHITECT HIV Ag/Ab Combo: 0.41 IU/mL versus 1.2 IU/mL (WHO) and 12.7 pg/mL versus 20.1 pg/mL (AFSSAPS); GS HIV Combo Ag/Ab EIA also demonstrated slightly better specificity compared to ARCHITECT HIV Ag/Ab Combo (100% versus 99.7%). The 4th generation HIV Combo tests detected seroconversion 7-11 days earlier than the 3rd generation HIV antibody only EIAs. Both 4th generation immunoassays demonstrated excellent performance in sensitivity, with the reduction of the serological window period (7-11 days earlier detection than the 3rd generation HIV tests). However, GS HIV Combo Ag/Ab demonstrated improved HIV antigen analytical sensitivity and slightly better specificity when compared to ARCHITECT HIV Ag/Ab Combo assay, with higher positive predictive values (PPV) for low prevalence populations. Copyright © 2013 Elsevier B.V. All rights reserved.

  3. Acceleration of age-associated methylation patterns in HIV-1-infected adults.

    Directory of Open Access Journals (Sweden)

    Tammy M Rickabaugh

    Full Text Available Patients with treated HIV-1-infection experience earlier occurrence of aging-associated diseases, raising speculation that HIV-1-infection, or antiretroviral treatment, may accelerate aging. We recently described an age-related co-methylation module comprised of hundreds of CpGs; however, it is unknown whether aging and HIV-1-infection exert negative health effects through similar, or disparate, mechanisms. We investigated whether HIV-1-infection would induce age-associated methylation changes. We evaluated DNA methylation levels at >450,000 CpG sites in peripheral blood mononuclear cells (PBMC of young (20-35 and older (36-56 adults in two separate groups of participants. Each age group for each data set consisted of 12 HIV-1-infected and 12 age-matched HIV-1-uninfected samples for a total of 96 samples. The effects of age and HIV-1 infection on methylation at each CpG revealed a strong correlation of 0.49, p<1 x 10(-200 and 0.47, p<1 x 10(-200. Weighted gene correlation network analysis (WGCNA identified 17 co-methylation modules; module 3 (ME3 was significantly correlated with age (cor=0.70 and HIV-1 status (cor=0.31. Older HIV-1+ individuals had a greater number of hypermethylated CpGs across ME3 (p=0.015. In a multivariate model, ME3 was significantly associated with age and HIV status (Data set 1: βage=0.007088, p=2.08 x 10(-9; βHIV=0.099574, p=0.0011; Data set 2: βage=0.008762, p=1.27 x 10(-5; βHIV=0.128649, p=0.0001. Using this model, we estimate that HIV-1 infection accelerates age-related methylation by approximately 13.7 years in data set 1 and 14.7 years in data set 2. The genes related to CpGs in ME3 are enriched for polycomb group target genes known to be involved in cell renewal and aging. The overlap between ME3 and an aging methylation module found in solid tissues is also highly significant (Fisher-exact p=5.6 x 10(-6, odds ratio=1.91. These data demonstrate that HIV-1 infection is associated with methylation patterns that

  4. Molecular and epidemiological characterization of HIV-1 subtypes among Libyan patients.

    Science.gov (United States)

    Daw, Mohamed A; El-Bouzedi, Abdallah; Ahmed, Mohamed O; Dau, Aghnyia A

    2017-04-28

    The epidemiological and clinical aspects of human immunodeficiency virus subtypes are of great interest worldwide. These subtypes are rarely studied in North African countries. Libya is a large country with the longest coast on the Mediterranean Sea, facing the Southern European countries. Studies on the characterization of HIV-1 subtypes are limited in Libya. This study aimed to determine the magnitude of the HIV problem among the Libyan population and to better understand the genetic diversity and the epidemiologic dynamics of HIV 1, as well as to correlate that with the risk factors involved. A total of 159 HIV-1 strains were collected from 814 HIV positive patients from the four Libyan regions during a 16-year period (1995-2010). To determine the HIV-1 subtypes, genetic analysis and molecular sequencing were carried out using provirus polygene. Epidemiologic and demographic information was obtained from each participant and correlated with HIV-1 subtypes using logistic regression. The overall prevalence of HIV among Libyans ranged from 5 to 10 per 100,000 during the study period. It was higher among intravenous drug users (IVDUs) (53.9%), blood recipients (25.9%) and heterosexuals (17.6%) than by vertical transmission (2.6%). Prevalence was higher among males aged 20-40 years (M:F 1:6, P > 0.001). Among the 159 strains of HIV-1 available for typing, 117 strains (73.6%) were subtype B, 29 (18.2%) were CRF02_AG, and 13 (8.2%) were subtype A. HIV-1 subtype B was the most prevalent all over the country, and it was more prevalent in the Northern region, particularly among IVDUs (P HIV-1 infection is emerging in Libya with a shifting prevalence of subtypes associated with the changing epidemiology of HIV-1 among risk groups. A genetic analysis of HIV-1 strains demonstrated low subtype heterogeneity with the evolution of subtype B, and CRF_20 AG, as well as HIV-1 subtype A. Our study highlights the importance of expanded surveillance programs to control HIV

  5. Ebselen, a Small-Molecule Capsid Inhibitor of HIV-1 Replication.

    Science.gov (United States)

    Thenin-Houssier, Suzie; de Vera, Ian Mitchelle S; Pedro-Rosa, Laura; Brady, Angela; Richard, Audrey; Konnick, Briana; Opp, Silvana; Buffone, Cindy; Fuhrmann, Jakob; Kota, Smitha; Billack, Blase; Pietka-Ottlik, Magdalena; Tellinghuisen, Timothy; Choe, Hyeryun; Spicer, Timothy; Scampavia, Louis; Diaz-Griffero, Felipe; Kojetin, Douglas J; Valente, Susana T

    2016-04-01

    The human immunodeficiency virus type 1 (HIV-1) capsid plays crucial roles in HIV-1 replication and thus represents an excellent drug target. We developed a high-throughput screening method based on a time-resolved fluorescence resonance energy transfer (HTS-TR-FRET) assay, using the C-terminal domain (CTD) of HIV-1 capsid to identify inhibitors of capsid dimerization. This assay was used to screen a library of pharmacologically active compounds, composed of 1,280in vivo-active drugs, and identified ebselen [2-phenyl-1,2-benzisoselenazol-3(2H)-one], an organoselenium compound, as an inhibitor of HIV-1 capsid CTD dimerization. Nuclear magnetic resonance (NMR) spectroscopic analysis confirmed the direct interaction of ebselen with the HIV-1 capsid CTD and dimer dissociation when ebselen is in 2-fold molar excess. Electrospray ionization mass spectrometry revealed that ebselen covalently binds the HIV-1 capsid CTD, likely via a selenylsulfide linkage with Cys198 and Cys218. This compound presents anti-HIV activity in single and multiple rounds of infection in permissive cell lines as well as in primary peripheral blood mononuclear cells. Ebselen inhibits early viral postentry events of the HIV-1 life cycle by impairing the incoming capsid uncoating process. This compound also blocks infection of other retroviruses, such as Moloney murine leukemia virus and simian immunodeficiency virus, but displays no inhibitory activity against hepatitis C and influenza viruses. This study reports the use of TR-FRET screening to successfully identify a novel capsid inhibitor, ebselen, validating HIV-1 capsid as a promising target for drug development. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

  6. Identification of conserved subdominant HIV Type 1 CD8(+) T Cell epitopes restricted within common HLA Supertypes for therapeutic HIV Type 1 vaccines

    DEFF Research Database (Denmark)

    Karlsson, Ingrid; Kløverpris, Henrik; Jensen, Kristoffer Jarlov

    2012-01-01

    The high HIV-1 prevalence, up to 4.6% in Guinea-Bissau, West Africa, makes it a relevant location for testing of therapeutic vaccines. With the aim of performing a clinical study in Guinea-Bissau, after first testing the vaccine for safety in Denmark, Europe, we here describe the design...... of a universal epitope peptide-based T cell vaccine with relevance for any geographic locations. The two major obstacles when designing such a vaccine are the high diversities of the HIV-1 genome and of the human major histocompatibility complex (MHC) class I. We selected 15 CD8-restricted epitopes predicted......-specific, HLA-restricted T cell specificities using peptide-MHC class I tetramer labeling of CD8(+) T cells from HIV-1-infected individuals. The selected vaccine epitopes are infrequently targeted in HIV-1-infected individuals from both locations. Moreover, we HLA-typed HIV-1-infected individuals...

  7. Continued Follow-Up of Phambili Phase 2b Randomized HIV-1 Vaccine Trial Participants Supports Increased HIV-1 Acquisition among Vaccinated Men.

    Directory of Open Access Journals (Sweden)

    Zoe Moodie

    Full Text Available The Phase 2b double-blinded, randomized Phambili/HVTN 503 trial evaluated safety and efficacy of the MRK Ad5 gag/pol/nef subtype B HIV-1 preventive vaccine vs placebo in sexually active HIV-1 seronegative participants in South Africa. Enrollment and vaccinations stopped and participants were unblinded but continued follow-up when the Step study evaluating the same vaccine in the Americas, Caribbean, and Australia was unblinded for non-efficacy. Final Phambili analyses found more HIV-1 infections amongst vaccine than placebo recipients, impelling the HVTN 503-S recall study.HVTN 503-S sought to enroll all 695 HIV-1 uninfected Phambili participants, provide HIV testing, risk reduction counseling, physical examination, risk behavior assessment and treatment assignment recall. After adding HVTN 503-S data, HIV-1 infection hazard ratios (HR vaccine vs. placebo were estimated by Cox models.Of the 695 eligible, 465 (67% enrolled with 230 from the vaccine group and 235 from the placebo group. 38% of the 184 Phambili dropouts were enrolled. Enrollment did not differ by treatment group, gender, or baseline HSV-2. With the additional 1286 person years of 503-S follow-up, the estimated HR over Phambili and HVTN 503-S follow-up was 1.52 (95% CI 1.08-2.15, p = 0.02, 82 vaccine/54 placebo infections. The HR was significant for men (HR = 2.75, 95% CI 1.49, 5.06, p = 0.001 but not for women (HR = 1.12, 95% CI 0.73, 1.72, p = 0.62.The additional follow-up from HVTN 503-S supported the Phambili finding of increased HIV-1 acquisition among vaccinated men and strengthened the evidence of lack of vaccine effect among women.clinicaltrials.gov NCT00413725 SA National Health Research Database DOH-27-0207-1539.

  8. Syphilis and HIV-1 co-infection: influence on CD4 T cell count, HIV-1 viral load and treatment response

    DEFF Research Database (Denmark)

    Kofoed, Kristian; Gerstoft, Jan; Mathiesen, Lars Reinhardt

    2006-01-01

    OBJECTIVES: To assess the effect of human immunodeficiency virus (HIV)-1 and syphilis coinfection on HIV-ribonucleic acid (RNA) viral load, CD4 cell count, and the response in rapid plasmin reagin (RPR) to treatment of the syphilis infection. STUDY DESIGN: Cases of syphilis diagnosed during 1 year...... in HIV-infected patients in Copenhagen were included. HIV-RNA, CD4 cell counts, and RPR-serology were measured before, during, and after syphilis. RESULTS: Forty-one patients were included. CD4 cell count decreased significantly during infection in patients with primary and secondary stages of syphilis...... (mean 106 cells/mm, P = 0.03). Treatment of syphilis was associated with an increase in the CD4 cell count and a decrease in HIV-RNA in the overall group (mean 66 cells/mm and -0.261 RNA log10 copies/ml, P = 0.02 and 0.04). The serological response rates for 15 patients treated with penicillin and 25...

  9. A prospective study of the effect of pregnancy on CD4 counts and plasma HIV-1 RNA concentrations of antiretroviral-naive HIV-1-infected women.

    Science.gov (United States)

    Heffron, Renee; Donnell, Deborah; Kiarie, James; Rees, Helen; Ngure, Kenneth; Mugo, Nelly; Were, Edwin; Celum, Connie; Baeten, Jared M

    2014-02-01

    In HIV-1-infected women, CD4 count declines occur during pregnancy, which has been attributed to hemodilution. However, for women who have not initiated antiretroviral therapy, it is unclear if CD4 declines are sustained beyond pregnancy and accompanied by increased viral levels, which could indicate an effect of pregnancy on accelerating HIV-1 disease progression. In a prospective study among 2269 HIV-1-infected antiretroviral therapy-naive women from 7 African countries, we examined the effect of pregnancy on HIV-1 disease progression. We used linear mixed models to compare CD4 counts and plasma HIV-1 RNA concentrations between pregnant, postpartum, and nonpregnant periods. Women contributed 3270 person-years of follow-up, during which time 476 women became pregnant. In adjusted analysis, CD4 counts were an average of 56 (95% confidence interval: 39 to 73) cells/mm lower during pregnant compared with nonpregnant periods and 70 (95% confidence interval: 53 to 88) cells/mm lower during pregnant compared with postpartum periods; these results were consistent when restricted to the subgroup of women who became pregnant. Plasma HIV-1 RNA concentrations were not different between pregnant and nonpregnant periods (P = 0.9) or pregnant and postpartum periods (P = 0.3). Neither CD4 counts nor plasma HIV-1 RNA levels were significantly different in postpartum compared with nonpregnant periods. CD4 count declines among HIV-1-infected women during pregnancy are temporary and not sustained in postpartum periods. Pregnancy does not have a short-term impact on plasma HIV-1 RNA concentrations.

  10. Creation of chimeric human/rabbit APOBEC1 with HIV-1 restriction and DNA mutation activities

    Science.gov (United States)

    Ikeda, Terumasa; Ong, Eugene Boon Beng; Watanabe, Nobumoto; Sakaguchi, Nobuo; Maeda, Kazuhiko; Koito, Atsushi

    2016-01-01

    APOBEC1 (A1) proteins from lagomorphs and rodents have deaminase-dependent restriction activity against HIV-1, whereas human A1 exerts a negligible effect. To investigate these differences in the restriction of HIV-1 by A1 proteins, a series of chimeric proteins combining rabbit and human A1s was constructed. Homology models of the A1s indicated that their activities derive from functional domains that likely act in tandem through a dimeric interface. The C-terminal region containing the leucine-rich motif and the dimerization domains of rabbit A1 is important for its anti-HIV-1 activity. The A1 chimeras with strong anti-HIV-1 activity were incorporated into virions more efficiently than those without anti-HIV-1 activity, and exhibited potent DNA-mutator activity. Therefore, the C-terminal region of rabbit A1 is involved in both its packaging into the HIV-1 virion and its deamination activity against both viral cDNA and genomic RNA. This study identifies the novel molecular mechanism underlying the target specificity of A1.

  11. A single gp120 residue can affect HIV-1 tropism in macaques.

    Directory of Open Access Journals (Sweden)

    Gregory Q Del Prete

    2017-09-01

    Full Text Available Species-dependent variation in proteins that aid or limit virus replication determines the ability of lentiviruses to jump between host species. Identifying and overcoming these differences facilitates the development of animal models for HIV-1, including models based on chimeric SIVs that express HIV-1 envelope (Env glycoproteins, (SHIVs and simian-tropic HIV-1 (stHIV strains. Here, we demonstrate that the inherently poor ability of most HIV-1 Env proteins to use macaque CD4 as a receptor is improved during adaptation by virus passage in macaques. We identify a single amino acid, A281, in HIV-1 Env that consistently changes during adaptation in macaques and affects the ability of HIV-1 Env to use macaque CD4. Importantly, mutations at A281 do not markedly affect HIV-1 Env neutralization properties. Our findings should facilitate the design of HIV-1 Env proteins for use in non-human primate models and thus expedite the development of clinically relevant reagents for testing interventions against HIV-1.

  12. Kaposi's-sarcoma-associated-herpesvirus-activated dendritic cells promote HIV-1 trans-infection and suppress CD4{sup +} T cell proliferation

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Wan; Qin, Yan; Bai, Lei [Key Laboratory of Molecular Virology and Immunology, Institute Pasteur of Shanghai, the Chinese Academy of Sciences, Shanghai (China); Graduate School of the Chinese Academy of Sciences, Beijing (China); Lan, Ke [Key Laboratory of Molecular Virology and Immunology, Institute Pasteur of Shanghai, the Chinese Academy of Sciences, Shanghai (China); Wang, Jian-Hua, E-mail: Jh_wang@sibs.ac.cn [Key Laboratory of Molecular Virology and Immunology, Institute Pasteur of Shanghai, the Chinese Academy of Sciences, Shanghai (China)

    2013-06-05

    Infection of Kaposi's sarcoma-associated herpesvirus (KSHV) is commonly occurred in AIDS patients. KSHV and HIV-1 act cooperatively in regulating infection with each other and in human carcinogenesis. Dendritic cells (DCs), as the pivotal cells in host immunity, may be modulated by both viruses, for immunoevasion and dissemination, therefore, the interaction between DCs and each virus has been a prior focus for pathogenesis elucidation. Here, we assessed the potential effect of KSHV on DC–HIV-1 interaction. We found that KSHV stimulation could promote maturation of monocyte-derived DCs (MDDCs) and impaired the ability of MDDCs to drive proliferation of resting CD4{sup +} T cells, demonstrating the immunosuppression induced by KSHV. More importantly, KSHV-stimulated MDDCs could capture more HIV-1 and efficiently transferred these infectious viruses to Hut/CCR5 T cell line. Our results reveal the novel modulation of DC-mediated HIV-1 dissemination by KSHV, and highlight the importance of studying DC–HIV-1 interaction to elucidate HIV/AIDS pathogenesis. - Highlights: ► KSHV impaired the ability of MDDCs to drive proliferation of resting CD4{sup +} T cells. ► KSHV stimulation matured MDDCs and enhanced HIV-1 endocytosis. ► KSHV stimulated MDDCs increased ICAM-1 expression and tighten contact with T cells. ► KSHV-stimulated MDDCs promoted HIV-1 trans-infection of CD4{sup +} T cells.

  13. Extracellular histones identified in crocodile blood inhibit in-vitro HIV-1 infection.

    Science.gov (United States)

    Kozlowski, Hannah N; Lai, Eric T L; Havugimana, Pierre C; White, Carl; Emili, Andrew; Sakac, Darinka; Binnington, Beth; Neschadim, Anton; McCarthy, Stephen D S; Branch, Donald R

    2016-08-24

    It has been reported that crocodile blood contains potent antibacterial and antiviral properties. However, its effects on HIV-1 infection remain unknown. We obtained blood from saltwater crocodiles to examine whether serum or plasma could inhibit HIV-1 infection. We purified plasma fractions then used liquid chromatography-mass spectrometry to identify the inhibitory protein factor(s). We then analyzed the ability of recombinant proteins to recapitulate HIV-1 inhibition and determine their mechanism of action. Crocodylus porosus plasma was tested for inhibition of Jurkat T-cell HIV-1 infection. Inhibitor(s) were purified by reverse-phase chromatography then identified by protein liquid chromatography-mass spectrometry. Anti-HIV-1 activity of purified plasma or recombinant proteins were measured by p24 enzyme-linked immunosorbent assay and luciferase readouts, and mechanism of action was determined by measuring HIV-1 RNA, cDNA and transcription (using 1G5 cells). Crocodile plasma contains potent inhibitors of HIV-1IIIB infection, which were identified as histones. Recombinant human histones H1 and H2A significantly reduced HIV-1JR-FL infection (IC50 of 0.79 and 0.45 μmol/l, respectively), whereas H4 enhanced JR-FL luciferase activity. The inhibitory effects of crocodile plasma, recombinant H1 or recombinant H2A on HIV-1 infection were during or post-viral transcription. Circulating histones in crocodile blood, possibly released by neutrophil extracellular traps, are significant inhibitors of HIV-1 infection in-vitro. Extracellular recombinant histones have different effects on HIV-1 transcription and protein expression and are downregulated in HIV-1 patients. Circulating histones may be a novel resistance factor during HIV-1 infection, and peptide versions should be explored as future HIV-1 therapeutics that modulate viral transcription.

  14. Brief Report: Medication Sharing Is Rare Among African HIV-1 Serodiscordant Couples Enrolled in an Efficacy Trial of Oral Pre-exposure Prophylaxis (PrEP) for HIV-1 Prevention.

    Science.gov (United States)

    Thomson, Kerry A; Haberer, Jessica E; Marzinke, Mark A; Mujugira, Andrew; Hendrix, Craig W; Celum, Connie; Ndase, Patrick; Ronald, Allan; Bangsberg, David R; Baeten, Jared M

    2017-06-01

    Sharing of pre-exposure prophylaxis (PrEP) medications is a concern for PrEP implementation. For HIV-1 serodiscordant couples, sharing may undermine the HIV-1 prevention benefit and also cause antiretroviral resistance if taken by HIV-1 infected partners. Within a PrEP efficacy trial among HIV-1 serodiscordant couples, we assessed the occurrence of PrEP sharing by self-report and plasma tenofovir concentrations in HIV-1 infected partners. PrEP sharing was self-reported at <0.01% of visits, and 0%-1.6% of randomly selected and 0% of purposively selected specimens from HIV-1 infected participants had detectable tenofovir concentrations (median: 66.5 ng/mL, range: 1.3-292 ng/mL). PrEP sharing within HIV-1 serodiscordant couples was extremely rare.

  15. Elimination of cancer stem cells and reactivation of latent HIV-1 via AMPK activation: Common mechanism of action linking inhibition of tumorigenesis and the potential eradication of HIV-1.

    Science.gov (United States)

    Finley, Jahahreeh

    2017-07-01

    that activation of AMPK, a master regulator of cellular metabolism that plays a critical role in T cell activation and differentiation of ESCs and ASCs, will lead to both T cell activation-induced latent HIV-1 reactivation, facilitating virus destruction, as well as "activation", differentiation, and/or apoptosis of CSCs, thus inhibiting tumorigenesis. We also propose the novel observation that compounds that have been shown to both facilitate latent HIV-1 reactivation and promote CSC differentiation/apoptosis (e.g. bryostatin-1, JQ1, metformin, butyrate, etc.) likely do so through a common mechanism of AMPK activation. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. HIV-1 transgenic rats develop T cell abnormalities

    International Nuclear Information System (INIS)

    Reid, William; Abdelwahab, Sayed; Sadowska, Mariola; Huso, David; Neal, Ashley; Ahearn, Aaron; Bryant, Joseph; Gallo, Robert C.; Lewis, George K.; Reitz, Marvin

    2004-01-01

    HIV-1 infection leads to impaired antigen-specific T cell proliferation, increased susceptibility of T cells to apoptosis, progressive impairment of T-helper 1 (Th1) responses, and altered maturation of HIV-1-specific memory cells. We have identified similar impairments in HIV-1 transgenic (Tg) rats. Tg rats developed an absolute reduction in CD4 + and CD8 + T cells able to produce IFN-γ following activation and an increased susceptibility of T cells to activation-induced apoptosis. CD4 + and CD8 + effector/memory (CD45RC - CD62L - ) pools were significantly smaller in Tg rats compared to non-Tg controls, although the converse was true for the naieve (CD45RC + CD62L + ) T cell pool. Our interpretation is that the HIV transgene causes defects in the development of T cell effector function and generation of specific effector/memory T cell subsets, and that activation-induced apoptosis may be an essential factor in this process

  17. Creatine protects against mitochondrial dysfunction associated with HIV-1 Tat-induced neuronal injury

    Science.gov (United States)

    Stevens, Patrick R.; Gawryluk, Jeremy W.; Hui, Liang; Chen, Xuesong; Geiger, Jonathan D.

    2015-01-01

    HIV-1 infected individuals are living longer but experiencing a prevalence rate of over 50% for HIV-1 associated neurocognitive disorders (HAND) for which no effective treatment is available. Viral and cellular factors secreted by HIV-1 infected cells leads to neuronal injury and HIV-1 Tat continues to be implicated in the pathogenesis of HAND. Here we tested the hypothesis that creatine protected against HIV-1 Tat-induced neuronal injury by preventing mitochondrial bioenergetic crisis and/or redox catastrophe. Creatine blocked HIV-1 Tat1-72-induced increases in neuron cell death and synaptic area loss. Creatine protected against HIV-1 Tat-induced decreases in ATP. Creatine and creatine plus HIV-1 Tat increased cellular levels of creatine, and creatine plus HIV-1 Tat further decreased ratios of phosphocreatine to creatine observed with creatine or HIV-1 Tat treatments alone. Additionally, creatine protected against HIV-1 Tat-induced mitochondrial hypopolarization and HIV-1 Tat-induced mitochondrial permeability transition pore opening. Thus, creatine may be a useful adjunctive therapy against HAND. PMID:25613139

  18. HMGB1 Is Involved in IFN-α Production and TRAIL Expression by HIV-1-Exposed Plasmacytoid Dendritic Cells: Impact of the Crosstalk with NK Cells.

    Directory of Open Access Journals (Sweden)

    Héla Saïdi

    2016-02-01

    Full Text Available Plasmacytoid dendritic cells (pDCs are innate sensors of viral infections and important mediators of antiviral innate immunity through their ability to produce large amounts of IFN-α. Moreover, Toll-like receptor 7 (TLR7 and 9 (TLR9 ligands, such as HIV and CpG respectively, turn pDCs into TRAIL-expressing killer pDCs able to lyse HIV-infected CD4+ T cells. NK cells can regulate antiviral immunity by modulating pDC functions, and pDC production of IFN-α as well as cell-cell contact is required to promote NK cell functions. Impaired pDC-NK cell crosstalk was reported in the setting of HIV-1 infection, but the impact of HIV-1 on TRAIL expression and innate antiviral immunity during this crosstalk is unknown. Here, we report that low concentrations of CCR5-tropic HIV-1Ba-L promote the release of pro-inflammatory cytokines such as IFN-α, TNF-α, IFN-γ and IL-12, and CCR5-interacting chemokines (MIP-1α and MIP-1β in NK-pDCs co-cultures. At high HIV-1BaL concentrations, the addition of NK cells did not promote the release of these mediators, suggesting that once efficiently triggered by the virus, pDCs could not integrate new activating signals delivered by NK cells. However, high HIV-1BaL concentrations were required to trigger IFN-α-mediated TRAIL expression at the surface of both pDCs and NK cells during their crosstalk. Interestingly, we identified the alarmin HMGB1, released at pDC-NK cell synapse, as an essential trigger for the secretion of IFN-α and IFN-related soluble mediators during the interplay of HIV-1 exposed pDCs with NK cells. Moreover, HMGB1 was found crucial for mTRAIL translocation to the plasma membrane of both pDCs and NK cells during their crosstalk following pDC exposure to HIV-1. Data from serum analyses of circulating HMGB1, HMGB1-specific antibodies, sTRAIL and IP-10 in a cohort of 67 HIV-1+ patients argue for the in vivo relevance of these observations. Altogether, these findings identify HMGB1 as a trigger for IFN

  19. HMGB1 Is Involved in IFN-α Production and TRAIL Expression by HIV-1-Exposed Plasmacytoid Dendritic Cells: Impact of the Crosstalk with NK Cells.

    Science.gov (United States)

    Saïdi, Héla; Bras, Marlène; Formaglio, Pauline; Melki, Marie-Thérèse; Charbit, Bruno; Herbeuval, Jean-Philippe; Gougeon, Marie-Lise

    2016-02-01

    Plasmacytoid dendritic cells (pDCs) are innate sensors of viral infections and important mediators of antiviral innate immunity through their ability to produce large amounts of IFN-α. Moreover, Toll-like receptor 7 (TLR7) and 9 (TLR9) ligands, such as HIV and CpG respectively, turn pDCs into TRAIL-expressing killer pDCs able to lyse HIV-infected CD4+ T cells. NK cells can regulate antiviral immunity by modulating pDC functions, and pDC production of IFN-α as well as cell-cell contact is required to promote NK cell functions. Impaired pDC-NK cell crosstalk was reported in the setting of HIV-1 infection, but the impact of HIV-1 on TRAIL expression and innate antiviral immunity during this crosstalk is unknown. Here, we report that low concentrations of CCR5-tropic HIV-1Ba-L promote the release of pro-inflammatory cytokines such as IFN-α, TNF-α, IFN-γ and IL-12, and CCR5-interacting chemokines (MIP-1α and MIP-1β) in NK-pDCs co-cultures. At high HIV-1BaL concentrations, the addition of NK cells did not promote the release of these mediators, suggesting that once efficiently triggered by the virus, pDCs could not integrate new activating signals delivered by NK cells. However, high HIV-1BaL concentrations were required to trigger IFN-α-mediated TRAIL expression at the surface of both pDCs and NK cells during their crosstalk. Interestingly, we identified the alarmin HMGB1, released at pDC-NK cell synapse, as an essential trigger for the secretion of IFN-α and IFN-related soluble mediators during the interplay of HIV-1 exposed pDCs with NK cells. Moreover, HMGB1 was found crucial for mTRAIL translocation to the plasma membrane of both pDCs and NK cells during their crosstalk following pDC exposure to HIV-1. Data from serum analyses of circulating HMGB1, HMGB1-specific antibodies, sTRAIL and IP-10 in a cohort of 67 HIV-1+ patients argue for the in vivo relevance of these observations. Altogether, these findings identify HMGB1 as a trigger for IFN

  20. Regulators of ribonucleotide reductase inhibit Ty1 mobility in saccharomyces cerevisiae

    Directory of Open Access Journals (Sweden)

    O'Donnell John P

    2010-11-01

    Full Text Available Abstract Background Ty1 is a long terminal repeat retrotransposon of Saccharomyces cerevisiae, with a replication cycle similar to retrovirus replication. Structurally, Ty1 contains long terminal repeat (LTR regions flanking the gag and pol genes that encode for the proteins that enable Ty1 mobility. Reverse transcriptase produces Ty1 complementary (cDNA that can either be integrated back into the genome by integrase or recombined into the yeast genome through homologous recombination. The frequency of Ty1 mobility is temperature sensitive, with optimum activity occurring at 24-26°C. Results In this study, we identified two host genes that when deleted allow for high temperature Ty1 mobility: RFX1 and SML1. The protein products of these genes are both negative regulators of the enzyme ribonucleotide reductase, a key enzyme in regulating deoxyribonucleotide triphosphate (dNTP levels in the cell. Processing of Ty1 proteins is defective at high temperature, and processing is not improved in either rfx1 or sml1 deletion strains. Ty1 mobility at high temperature is mediated by homologous recombination of Ty1 cDNA to Ty1 elements within the yeast genome. We quantified cDNA levels in wild type, rfx1 and sml1 deletion background strains at different temperatures. Southern blot analysis demonstrated that cDNA levels were not markedly different between the wild type and mutant strains as temperatures increased, indicating that the increased Ty1 mobility is not a result of increased cDNA synthesis in the mutant strains. Homologous recombination efficiency was increased in both rfx1 and sml1 deletion strains at high temperatures; the rfx1 deletion strain also had heightened homologous recombination efficiency at permissive temperatures. In the presence of the dNTP reducing agent hydroxyurea at permissive temperatures, Ty1 mobility was stimulated in the wild type and sml1 deletion strains but not in the rfx1 deletion strain. Mobility frequency was greatly

  1. HIV-1 nef suppression by virally encoded microRNA

    Directory of Open Access Journals (Sweden)

    Brisibe Ebiamadon

    2004-12-01

    Full Text Available Abstract Background MicroRNAs (miRNAs are 21~25-nucleotides (nt long and interact with mRNAs to trigger either translational repression or RNA cleavage through RNA interference (RNAi, depending on the degree of complementarity with the target mRNAs. Our recent study has shown that HIV-1 nef dsRNA from AIDS patients who are long-term non-progressors (LTNPs inhibited the transcription of HIV-1. Results Here, we show the possibility that nef-derived miRNAs are produced in HIV-1 persistently infected cells. Furthermore, nef short hairpin RNA (shRNA that corresponded to a predicted nef miRNA (~25 nt, miR-N367 can block HIV-1 Nef expression in vitro and the suppression by shRNA/miR-N367 would be related with low viremia in an LTNP (15-2-2. In the 15-2-2 model mice, the weight loss, which may be rendered by nef was also inhibited by shRNA/miR-N367 corresponding to suppression of nef expression in vivo. Conclusions These data suggest that nef/U3 miRNAs produced in HIV-1-infected cells may suppress both Nef function and HIV-1 virulence through the RNAi pathway.

  2. Diabetes mellitus and impaired fasting glucose in ART-naïve patients with HIV-1, HIV-2 and HIV-1/2 dual infection in Guinea-Bissau

    DEFF Research Database (Denmark)

    Steiniche, Ditte; Jespersen, Sanne; Erikstrup, Christian

    2016-01-01

    BACKGROUND: The prevalence of diabetes mellitus (DM) is expected to increase in sub-Saharan Africa. Patients with HIV are at particular risk. We investigated the DM burden among antiretroviral therapy (ART)-naïve patients with HIV in Guinea-Bissau. METHODS: Patients were consecutively included. D...... age and a family history of DM apply also for ART-naïve patients with HIV.......BACKGROUND: The prevalence of diabetes mellitus (DM) is expected to increase in sub-Saharan Africa. Patients with HIV are at particular risk. We investigated the DM burden among antiretroviral therapy (ART)-naïve patients with HIV in Guinea-Bissau. METHODS: Patients were consecutively included....... Demographic and lifestyle data were collected and one fasting blood glucose (FBG) measurement was used to diagnose DM (FBG≥7.0 mmol/L) and impaired fasting glucose (IFG) (FBG≥6.1 and ART-naïve patients with HIV had been included in the study of whom 893...

  3. Ectopic expression of anti-HIV-1 shRNAs protects CD8+ T cells modified with CD4ζ CAR from HIV-1 infection and alleviates impairment of cell proliferation

    International Nuclear Information System (INIS)

    Kamata, Masakazu; Kim, Patrick Y.; Ng, Hwee L.; Ringpis, Gene-Errol E.; Kranz, Emiko; Chan, Joshua; O'Connor, Sean; Yang, Otto O.; Chen, Irvin S.Y.

    2015-01-01

    Chimeric antigen receptors (CARs) are artificially engineered receptors that confer a desired specificity to immune effector T cells. As an HIV-1-specific CAR, CD4ζ CAR has been extensively tested in vitro as well as in clinical trials. T cells modified with this CAR mediated highly potent anti-HIV-1 activities in vitro and were well-tolerated in vivo, but exerted limited effects on viral load and reservoir size due to poor survival and/or functionality of the transduced cells in patients. We hypothesize that ectopic expression of CD4ζ on CD8 + T cells renders them susceptible to HIV-1 infection, resulting in poor survival of those cells. To test this possibility, highly purified CD8 + T cells were genetically modified with a CD4ζ-encoding lentiviral vector and infected with HIV-1. CD8 + T cells were vulnerable to HIV-1 infection upon expression of CD4ζ as evidenced by elevated levels of p24 Gag in cells and culture supernatants. Concurrently, the number of CD4ζ-modified CD8 + T cells was reduced relative to control cells upon HIV-1 infection. To protect these cells from HIV-1 infection, we co-expressed two anti-HIV-1 shRNAs previously developed by our group together with CD4ζ. This combination vector was able to suppress HIV-1 infection without impairing HIV-1-dependent effector activities of CD4ζ. In addition, the number of CD4ζ-modified CD8 + T cells maintained similar levels to that of the control even under HIV-1 infection. These results suggest that protecting CD4ζ-modified CD8 + T cells from HIV-1 infection is required for prolonged HIV-1-specific immune surveillance. - Highlights: • Ectopic expression of CD4ζ CAR in CD8 + T cells renders them susceptible to HIV-1 infection. • Co-expression of two anti-HIV-1 shRNAs protects CD4ζ CAR-modified CD8 + T cells from HIV-1 infection. • Protecting CD4ζ CAR-modified CD8 + T cells from HIV-1 infection suppresses its cytopathic effect

  4. The Latent Reservoir for HIV-1: How Immunologic Memory and Clonal Expansion Contribute to HIV-1 Persistence

    Science.gov (United States)

    Murray, Alexandra J.; Kwon, Kyungyoon J.; Farber, Donna L.; Siliciano, Robert F.

    2016-01-01

    Combination antiretroviral therapy (ART) for HIV-1 infection reduces plasma virus levels to below the limit of detection of clinical assays. However, even with prolonged suppression of viral replication with ART, viremia rebounds rapidly after treatment interruption. Thus ART is not curative. The principal barrier to cure is a remarkably stable reservoir of latent HIV-1 in resting memory CD4+ T cells. Here we consider explanations for the remarkable stability of the latent reservoir. Stability does not appear to reflect replenishment from new infection events but rather normal physiologic processes that provide for immunologic memory. Of particular importance are proliferative processes that drive clonal expansion of infected cells. Recent evidence suggests that in some infected cells, proliferation is a consequence of proviral integration into host genes associated with cell growth. Efforts to cure HIV-1 infection by targeting the latent reservoir may need to consider the potential of latently infected cells to proliferate. PMID:27382129

  5. HIV-1 and recombinant gp120 affect the survival and differentiation of human vessel wall-derived mesenchymal stem cells

    Directory of Open Access Journals (Sweden)

    Pasquinelli Gianandrea

    2011-05-01

    Full Text Available Abstract Background HIV infection elicits the onset of a progressive immunodeficiency and also damages several other organs and tissues such as the CNS, kidney, heart, blood vessels, adipose tissue and bone. In particular, HIV infection has been related to an increased incidence of cardiovascular diseases and derangement in the structure of blood vessels in the absence of classical risk factors. The recent characterization of multipotent mesenchymal cells in the vascular wall, involved in regulating cellular homeostasis, suggests that these cells may be considered a target of HIV pathogenesis. This paper investigated the interaction between HIV-1 and vascular wall resident human mesenchymal stem cells (MSCs. Results MSCs were challenged with classical R5 and X4 HIV-1 laboratory strains demonstrating that these strains are able to enter and integrate their retro-transcribed proviral DNA in the host cell genome. Subsequent experiments indicated that HIV-1 strains and recombinant gp120 elicited a reliable increase in apoptosis in sub-confluent MSCs. Since vascular wall MSCs are multipotent cells that may be differentiated towards several cell lineages, we challenged HIV-1 strains and gp120 on MSCs differentiated to adipogenesis and endotheliogenesis. Our experiments showed that the adipogenesis is increased especially by upregulated PPARγ activity whereas the endothelial differentiation induced by VEGF treatment was impaired with a downregulation of endothelial markers such as vWF, Flt-1 and KDR expression. These viral effects in MSC survival and adipogenic or endothelial differentiation were tackled by CD4 blockade suggesting an important role of CD4/gp120 interaction in this context. Conclusions The HIV-related derangement of MSC survival and differentiation may suggest a direct role of HIV infection and gp120 in impaired vessel homeostasis and in genesis of vessel damage observed in HIV-infected patients.

  6. HIV-1 DNA predicts disease progression and post-treatment virological control

    Science.gov (United States)

    Williams, James P; Hurst, Jacob; Stöhr, Wolfgang; Robinson, Nicola; Brown, Helen; Fisher, Martin; Kinloch, Sabine; Cooper, David; Schechter, Mauro; Tambussi, Giuseppe; Fidler, Sarah; Carrington, Mary; Babiker, Abdel; Weber, Jonathan

    2014-01-01

    In HIV-1 infection, a population of latently infected cells facilitates viral persistence despite antiretroviral therapy (ART). With the aim of identifying individuals in whom ART might induce a period of viraemic control on stopping therapy, we hypothesised that quantification of the pool of latently infected cells in primary HIV-1 infection (PHI) would predict clinical progression and viral replication following ART. We measured HIV-1 DNA in a highly characterised randomised population of individuals with PHI. We explored associations between HIV-1 DNA and immunological and virological markers of clinical progression, including viral rebound in those interrupting therapy. In multivariable analyses, HIV-1 DNA was more predictive of disease progression than plasma viral load and, at treatment interruption, predicted time to plasma virus rebound. HIV-1 DNA may help identify individuals who could safely interrupt ART in future HIV-1 eradication trials. Clinical trial registration: ISRCTN76742797 and EudraCT2004-000446-20 DOI: http://dx.doi.org/10.7554/eLife.03821.001 PMID:25217531

  7. Raltegravir cerebrospinal fluid concentrations in HIV-1 infection.

    Directory of Open Access Journals (Sweden)

    Aylin Yilmaz

    2009-09-01

    Full Text Available Raltegravir is an HIV-1 integrase inhibitor currently used in treatment-experienced HIV-1-infected patients resistant to other drug classes. In order to assess its central nervous system penetration, we measured raltegravir concentrations in cerebrospinal fluid (CSF and plasma in subjects receiving antiretroviral treatment regimens containing this drug.Raltegravir concentrations were determined by liquid chromatography tandem mass spectrometry in 25 paired CSF and plasma samples from 16 HIV-1-infected individuals. The lower limit of quantitation was 2.0 ng/ml for CSF and 10 ng/ml for plasma.Twenty-four of the 25 CSF samples had detectable raltegravir concentrations with a median raltegravir concentration of 18.4 ng/ml (range, <2.0-126.0. The median plasma raltegravir concentration was 448 ng/ml (range, 37-5180. CSF raltegravir concentrations correlated with CSF:plasma albumin ratios and CSF albumin concentrations.Approximately 50% of the CSF specimens exceeded the IC(95 levels reported to inhibit HIV-1 strains without resistance to integrase inhibitors. In addition to contributing to control of systemic HIV-1 infection, raltegravir achieves local inhibitory concentrations in CSF in most, but not all, patients. Blood-brain and blood-CSF barriers likely restrict drug entry, while enhanced permeability of these barriers enhances drug entry.

  8. Raltegravir cerebrospinal fluid concentrations in HIV-1 infection.

    Science.gov (United States)

    Yilmaz, Aylin; Gisslén, Magnus; Spudich, Serena; Lee, Evelyn; Jayewardene, Anura; Aweeka, Francesca; Price, Richard W

    2009-09-01

    Raltegravir is an HIV-1 integrase inhibitor currently used in treatment-experienced HIV-1-infected patients resistant to other drug classes. In order to assess its central nervous system penetration, we measured raltegravir concentrations in cerebrospinal fluid (CSF) and plasma in subjects receiving antiretroviral treatment regimens containing this drug. Raltegravir concentrations were determined by liquid chromatography tandem mass spectrometry in 25 paired CSF and plasma samples from 16 HIV-1-infected individuals. The lower limit of quantitation was 2.0 ng/ml for CSF and 10 ng/ml for plasma. Twenty-four of the 25 CSF samples had detectable raltegravir concentrations with a median raltegravir concentration of 18.4 ng/ml (range, <2.0-126.0). The median plasma raltegravir concentration was 448 ng/ml (range, 37-5180). CSF raltegravir concentrations correlated with CSF:plasma albumin ratios and CSF albumin concentrations. Approximately 50% of the CSF specimens exceeded the IC(95) levels reported to inhibit HIV-1 strains without resistance to integrase inhibitors. In addition to contributing to control of systemic HIV-1 infection, raltegravir achieves local inhibitory concentrations in CSF in most, but not all, patients. Blood-brain and blood-CSF barriers likely restrict drug entry, while enhanced permeability of these barriers enhances drug entry.

  9. Potential use of rapamycin in HIV infection

    DEFF Research Database (Denmark)

    Donia, Marco; McCubrey, James A; Bendtzen, Klaus

    2010-01-01

    The strong need for the development of alternative anti-HIV agents is primarily due to the emergence of strain-resistant viruses, the need for sustained adherence to complex treatment regimens and the toxicity of currently used antiviral drugs. This review analyzes proof of concept studies...... indicating that the immunomodulatory drug rapamycin (RAPA) possesses anti-HIV properties both in vitro and in vivo that qualifies it as a potential new anti-HIV drug. It represents a literature review of published studies that evaluated the in vitro and in vivo activity of RAPA in HIV. RAPA represses HIV-1...... replication in vitro through different mechanisms including, but not limited, to down regulation of CCR5. In addition RAPA synergistically enhances the anti-HIV activity of entry inhibitors such as vicriviroc, aplaviroc and enfuvirtide in vitro. RAPA also inhibits HIV-1 infection in human peripheral blood...

  10. The Gut Microbiome and HIV-1 Pathogenesis: A Two Way Street

    Science.gov (United States)

    Dillon, Stephanie M.; Frank, Daniel N.; Wilson, Cara C.

    2016-01-01

    HIV-1 infection is associated with substantial damage to the gastrointestinal (GI) tract resulting in structural impairment of the epithelial barrier and a disruption of intestinal homeostasis. The accompanying translocation of microbial products and potentially microbes themselves from the lumen into systemic circulation has been linked to immune activation, inflammation, and HIV-1 disease progression. The importance of microbial translocation in the setting of HIV-1 infection has led to a recent focus on understanding how the communities of microbes that make up the intestinal microbiome are altered during HIV-1 infection and how they interact with mucosal immune cells to contribute to inflammation. This review details the dysbiotic intestinal communities associated with HIV-1 infection and their potential link to HIV-1 pathogenesis. We detail studies that begin to address the mechanisms driving microbiota-associated immune activation and inflammation and the various treatment strategies aimed at correcting dysbiosis and improving the overall health of HIV-1 infected individuals. Finally, we discuss how this relatively new field of research can advance to provide a more comprehensive understanding of the contribution of the gut microbiome to HIV-1 pathogenesis. PMID:27755100

  11. Uridine metabolism in HIV-1-infected patients: effect of infection, of antiretroviral therapy and of HIV-1/ART-associated lipodystrophy syndrome.

    Directory of Open Access Journals (Sweden)

    Pere Domingo

    Full Text Available BACKGROUND: Uridine has been advocated for the treatment of HIV-1/HAART-associated lipodystrophy (HALS, although its metabolism in HIV-1-infected patients is poorly understood. METHODS: Plasma uridine concentrations were measured in 35 controls and 221 HIV-1-infected patients and fat uridine in 15 controls and 19 patients. The diagnosis of HALS was performed following the criteria of the Lipodystrophy Severity Grading Scale. Uridine was measured by a binary gradient-elution HPLC method. Analysis of genes encoding uridine metabolizing enzymes in fat was performed with TaqMan RT-PCR. RESULTS: Median plasma uridine concentrations for HIV-1-infected patients were 3.80 µmol/l (interquartile range: 1.60, and for controls 4.60 µmol/l (IQR: 1.8 (P = 0.0009. In fat, they were of 6.0 (3.67, and 2.8 (4.65 nmol/mg of protein, respectively (P = 0.0118. Patients with a mixed HALS form had a median plasma uridine level of 4.0 (IC95%: 3.40-4.80 whereas in those with isolated lipoatrophy it was 3.25 (2.55-4.15 µmol/l/l (P = 0.0066. The expression of uridine cytidine kinase and uridine phosphorylase genes was significantly decreased in all groups of patients with respect to controls. A higher expression of the mRNAs for concentrative nucleoside transporters was found in HIV-1-infected patients with respect to healthy controls. CONCLUSIONS: HIV-1 infection is associated with a decrease in plasma uridine and a shift of uridine to the adipose tissue compartment. Antiretroviral therapy was not associated with plasma uridine concentrations, but pure lipoatrophic HALS was associated with significantly lower plasma uridine concentrations.

  12. A prospective study of the effect of pregnancy on CD4 counts and plasma HIV-1 RNA concentrations of antiretroviral-naive HIV-1 infected women

    Science.gov (United States)

    Heffron, Renee; Donnell, Deborah; Kiarie, James; Rees, Helen; Ngure, Kenneth; Mugo, Nelly; Were, Edwin; Celum, Connie; Baeten, Jared M.

    2014-01-01

    Background In HIV-1 infected women, CD4 count declines occur during pregnancy, which has been attributed to hemodilution. However, for women who have not initiated antiretroviral therapy (ART), it is unclear if CD4 declines are sustained beyond pregnancy and accompanied by increased viral levels, which could indicate an effect of pregnancy on accelerating HIV-1 disease progression. Methods In a prospective study among 2269 HIV-1 infected ART-naïve women from 7 African countries, we examined the effect of pregnancy on HIV-1 disease progression. We used linear mixed models to compare CD4 counts and plasma HIV-1 RNA concentrations between pregnant, postpartum and non-pregnant periods. Results Women contributed 3270 person-years of follow-up, during which time 476 women became pregnant. In adjusted analysis, CD4 counts were an average of 56 (95% CI 39-73) cells/mm3 lower during pregnant compared to non-pregnant periods and 70 (95% CI 53-88) cells/mm3 lower during pregnant compared to postpartum periods; these results were consistent when restricted to the subgroup of women who became pregnant. Plasma HIV-1 RNA concentrations were not different between pregnant and non-pregnant periods (p=0.9) or pregnant and postpartum periods (p=0.3). Neither CD4 counts nor plasma HIV-1 RNA levels were significantly different in postpartum compared to non-pregnant periods. Conclusion CD4 count declines among HIV-1 infected women during pregnancy are temporary and not sustained in postpartum periods. Pregnancy does not have a short term impact on plasma HIV-1 RNA concentrations. PMID:24442226

  13. Transcriptionally active LTR retrotransposons in Eucalyptus genus are differentially expressed and insertionally polymorphic.

    Science.gov (United States)

    Marcon, Helena Sanches; Domingues, Douglas Silva; Silva, Juliana Costa; Borges, Rafael Junqueira; Matioli, Fábio Filippi; Fontes, Marcos Roberto de Mattos; Marino, Celso Luis

    2015-08-14

    In Eucalyptus genus, studies on genome composition and transposable elements (TEs) are particularly scarce. Nearly half of the recently released Eucalyptus grandis genome is composed by retrotransposons and this data provides an important opportunity to understand TE dynamics in Eucalyptus genome and transcriptome. We characterized nine families of transcriptionally active LTR retrotransposons from Copia and Gypsy superfamilies in Eucalyptus grandis genome and we depicted genomic distribution and copy number in two Eucalyptus species. We also evaluated genomic polymorphism and transcriptional profile in three organs of five Eucalyptus species. We observed contrasting genomic and transcriptional behavior in the same family among different species. RLC_egMax_1 was the most prevalent family and RLC_egAngela_1 was the family with the lowest copy number. Most families of both superfamilies have their insertions occurring Eucalyptus species. Using EST analysis and qRT-PCRs, we observed transcriptional activity in several tissues and in all evaluated species. In some families, osmotic stress increases transcript values. Our strategy was successful in isolating transcriptionally active retrotransposons in Eucalyptus, and each family has a particular genomic and transcriptional pattern. Overall, our results show that retrotransposon activity have differentially affected genome and transcriptome among Eucalyptus species.

  14. Electron tomography of HIV-1 infection in gut-associated lymphoid tissue.

    Science.gov (United States)

    Ladinsky, Mark S; Kieffer, Collin; Olson, Gregory; Deruaz, Maud; Vrbanac, Vladimir; Tager, Andrew M; Kwon, Douglas S; Bjorkman, Pamela J

    2014-01-01

    Critical aspects of HIV-1 infection occur in mucosal tissues, particularly in the gut, which contains large numbers of HIV-1 target cells that are depleted early in infection. We used electron tomography (ET) to image HIV-1 in gut-associated lymphoid tissue (GALT) of HIV-1-infected humanized mice, the first three-dimensional ultrastructural examination of HIV-1 infection in vivo. Human immune cells were successfully engrafted in the mice, and following infection with HIV-1, human T cells were reduced in GALT. Virions were found by ET at all stages of egress, including budding immature virions and free mature and immature viruses. Immuno-electron microscopy verified the virions were HIV-1 and showed CD4 sequestration in the endoplasmic reticulum of infected cells. Observation of HIV-1 in infected GALT tissue revealed that most HIV-1-infected cells, identified by immunolabeling and/or the presence of budding virions, were localized to intestinal crypts with pools of free virions concentrated in spaces between cells. Fewer infected cells were found in mucosal regions and the lamina propria. The preservation quality of reconstructed tissue volumes allowed details of budding virions, including structures interpreted as host-encoded scission machinery, to be resolved. Although HIV-1 virions released from infected cultured cells have been described as exclusively mature, we found pools of both immature and mature free virions within infected tissue. The pools could be classified as containing either mostly mature or mostly immature particles, and analyses of their proximities to the cell of origin supported a model of semi-synchronous waves of virion release. In addition to HIV-1 transmission by pools of free virus, we found evidence of transmission via virological synapses. Three-dimensional EM imaging of an active infection within tissue revealed important differences between cultured cell and tissue infection models and furthered the ultrastructural understanding of

  15. Electron tomography of HIV-1 infection in gut-associated lymphoid tissue.

    Directory of Open Access Journals (Sweden)

    Mark S Ladinsky

    2014-01-01

    Full Text Available Critical aspects of HIV-1 infection occur in mucosal tissues, particularly in the gut, which contains large numbers of HIV-1 target cells that are depleted early in infection. We used electron tomography (ET to image HIV-1 in gut-associated lymphoid tissue (GALT of HIV-1-infected humanized mice, the first three-dimensional ultrastructural examination of HIV-1 infection in vivo. Human immune cells were successfully engrafted in the mice, and following infection with HIV-1, human T cells were reduced in GALT. Virions were found by ET at all stages of egress, including budding immature virions and free mature and immature viruses. Immuno-electron microscopy verified the virions were HIV-1 and showed CD4 sequestration in the endoplasmic reticulum of infected cells. Observation of HIV-1 in infected GALT tissue revealed that most HIV-1-infected cells, identified by immunolabeling and/or the presence of budding virions, were localized to intestinal crypts with pools of free virions concentrated in spaces between cells. Fewer infected cells were found in mucosal regions and the lamina propria. The preservation quality of reconstructed tissue volumes allowed details of budding virions, including structures interpreted as host-encoded scission machinery, to be resolved. Although HIV-1 virions released from infected cultured cells have been described as exclusively mature, we found pools of both immature and mature free virions within infected tissue. The pools could be classified as containing either mostly mature or mostly immature particles, and analyses of their proximities to the cell of origin supported a model of semi-synchronous waves of virion release. In addition to HIV-1 transmission by pools of free virus, we found evidence of transmission via virological synapses. Three-dimensional EM imaging of an active infection within tissue revealed important differences between cultured cell and tissue infection models and furthered the ultrastructural

  16. HIV-1 Nef in Macrophage-Mediated Disease Pathogenesis

    Science.gov (United States)

    Lamers, Susanna L.; Fogel, Gary B.; Singer, Elyse J.; Salemi, Marco; Nolan, David J.; Huysentruyt, Leanne C.; McGrath, Michael S.

    2013-01-01

    Combined anti-retroviral therapy (cART) has significantly reduced the number of AIDS-associated illnesses and changed the course of HIV-1 disease in developed countries. Despite the ability of cART to maintain high CD4+ T-cell counts, a number of macrophage-mediated diseases can still occur in HIV-infected subjects. These diseases include lymphoma, metabolic diseases, and HIV-associated neurological disorders. Within macrophages, the HIV-1 regulatory protein “Nef” can modulate surface receptors, interact with signaling pathways, and promote specific environments that contribute to each of these pathologies. Moreover, genetic variation in Nef may also guide the macrophage response. Herein, we review findings relating to the Nef–macrophage interaction and how this relationship contributes to disease pathogenesis. PMID:23215766

  17. Neuropsychological performance in patients with asymptomatic HIV-1 infection.

    Science.gov (United States)

    Martínez-Banfi, Martha; Vélez, Jorge I; Perea, M Victoria; García, Ricardo; Puentes-Rozo, Pedro J; Mebarak Chams, Moises; Ladera, Valentina

    2018-05-01

    Human immunodeficiency virus (HIV-1) infection and acquired immunodeficiency syndrome (AIDS) lead to neurocognitive disorders; however, there is still much knowledge to be gained regarding HIV-associated neurocognitive disorders. The purpose of this study was to assess the cognitive performance, instrumental activities of daily living, depression, and anxiety in patients with asymptomatic HIV-1 infections compared with seronegative participants without neurocognitive impairment. We studied a sample consisted of 60 patients with asymptomatic HIV-1 infections and 60 seronegative participants without neurocognitive impairment from the city of Barranquilla, Colombia, with a mean age of 36.07 years. A protocol of neuropsychological and psychopathological tests was applied to the participants. The group of patients with asymptomatic HIV infections significantly underperformed on tasks that assessed global cognitive screening, attention span, learning, phonemic verbal fluency, auditory-verbal comprehension, information processing speed, cognitive flexibility, and motor skills compared to the group of seronegative participants. No significant differences were found in memory, visual confrontation naming, vocabulary, inhibition, and instrumental activities of daily living. Additionally, the patients with asymptomatic HIV-1 infection had a higher anxiety index than the seronegative participants, but no significant difference was found in depression. A correlation was found between depression and anxiety. In conclusion, the patients with asymptomatic HIV-1 infection had lower cognitive performances than the seronegative participants in the cognitive functions mentioned above and more anxiety but still performed the instrumental activities of daily living.

  18. Molecular epidemiology of HIV-1 among the HIV infected people of Manipur, Northeastern India: Emergence of unique recombinant forms.

    Science.gov (United States)

    Sharma, Adhikarimayum Lakhikumar; Singh, Thiyam Ramsing; Devi, Khuraijam Ranjana; Singh, Lisam Shanjukumar

    2017-06-01

    According to the Joint National Programme on HIV/AIDS (UNAIDS), the northeastern region of India has the highest HIV prevalence in the country. This study was conducted to determine the current HIV-1 molecular epidemiology of Manipur, a state in northeast India. Blood samples from HIV-1 seropositive subjects were collected between June 2011 and February 2014. The partial regions of HIV-1 genes; pol and tat-vpu-env were independently amplified, sequenced, analyzed, and genotyped. Based on all sequences generated from 110 samples using pol and/or tat-vpu-env gene, the overall HIV-1 genotypes distribution of Manipur was as follows: 65.45% (72/110) subtype C, 32.73% (36/110) unique recombinant forms (URFs), and 1.82% (2/110) subtype B. The distribution of HIV-1 genotypes among the risk groups was: heterosexual: 58.33% (35/60) subtype C, 38.33% (23/60) URFs, and 3.34% (2/60) subtype B; intravenous drug users (IDUs): 85.36% (35/41) subtype C, 9.76% (4/41) URFs, and 4.88% (2/41) subtype B; mother to child (MTC): 50% (3/6) URFs and 50% (3/6) subtype C and blood transfusion: 100% (3/3) subtype C. The findings for the first time revealed the emergence of URFs of HIV-1 in Manipur which is predominant among the sexual and MTC risk groups as compared to IDUs. Taking together, this study illustrated that Manipur is the "recombinant hotspot of HIV" of India. The results will provide the clinical importance for continuous monitoring of HIV-infections in order to design appropriate prevention measures to limit the spread of new HIV infections. © 2016 Wiley Periodicals, Inc.

  19. Potent inhibition of HIV-1 replication by a Tat mutant.

    Directory of Open Access Journals (Sweden)

    Luke W Meredith

    Full Text Available Herein we describe a mutant of the two-exon HIV-1 Tat protein, termed Nullbasic, that potently inhibits multiple steps of the HIV-1 replication cycle. Nullbasic was created by replacing the entire arginine-rich basic domain of wild type Tat with glycine/alanine residues. Like similarly mutated one-exon Tat mutants, Nullbasic exhibited transdominant negative effects on Tat-dependent transactivation. However, unlike previously reported mutants, we discovered that Nullbasic also strongly suppressed the expression of unspliced and singly-spliced viral mRNA, an activity likely caused by redistribution and thus functional inhibition of HIV-1 Rev. Furthermore, HIV-1 virion particles produced by cells expressing Nullbasic had severely reduced infectivity, a defect attributable to a reduced ability of the virions to undergo reverse transcription. Combination of these inhibitory effects on transactivation, Rev-dependent mRNA transport and reverse transcription meant that permissive cells constitutively expressing Nullbasic were highly resistant to a spreading infection by HIV-1. Nullbasic and its activities thus provide potential insights into the development of potent antiviral therapeutics that target multiple stages of HIV-1 infection.

  20. Vaginal Lactobacillus Inhibits HIV-1 Replication in Human Tissues Ex Vivo

    Directory of Open Access Journals (Sweden)

    Rogers A. Ñahui Palomino

    2017-05-01

    Full Text Available Lactobacillus species, which dominate vaginal microbiota of healthy reproductive-age women, lower the risks of sexually transmitted infections, including the risk of human immunodeficiency virus (HIV acquisition. The exact mechanisms of this protection remain to be understood. Here, we investigated these mechanisms in the context of human cervico-vaginal and lymphoid tissues ex vivo. We found that all six Lactobacillus strains tested in these systems significantly suppressed HIV type-1 (HIV-1 infection. We identified at least three factors that mediated this suppression: (i Acidification of the medium. The pH of the undiluted medium conditioned by lactobacilli was between 3.8 and 4.6. Acidification of the culture medium with hydrochloric acid (HCl to this pH in control experiments was sufficient to abrogate HIV-1 replication. However, the pH of the Lactobacillus-conditioned medium (CM diluted fivefold, which reached ∼6.9, was also suppressive for HIV-1 infection, while in control experiments HIV-1 infection was not abrogated when the pH of the medium was brought to 6.9 through the use of HCl. This suggested the existence of other factors responsible for HIV-1 inhibition by lactobacilli. (ii Lactic acid. There was a correlation between the concentration of lactic acid in the Lactobacillus-CM and its ability to suppress HIV-1 infection in human tissues ex vivo. Addition of lactic acid isomers D and L to tissue culture medium at the concentration that corresponded to their amount released by lactobacilli resulted in HIV-1 inhibition. Isomer L was produced in higher quantities than isomer D and was mostly responsible for HIV-1 inhibition. These results indicate that lactic acid, in particular its L-isomer, inhibits HIV-1 independently of lowering of the pH. (iii Virucidal effect. Incubation of HIV-1 in Lactobacillus-CM significantly suppressed viral infectivity for human tissues ex vivo. Finally, lactobacilli adsorb HIV-1, serving as a sink

  1. Phylodynamics of HIV-1 subtype F1 in Angola, Brazil and Romania.

    Science.gov (United States)

    Bello, Gonzalo; Afonso, Joana Morais; Morgado, Mariza G

    2012-07-01

    The HIV-1 subtype F1 is exceptionally prevalent in Angola, Brazil and Romania. The epidemiological context in which the spread of HIV occurred was highly variable from one country to another, mainly due to the existence of a long-term civil war in Angola and the contamination of a large number of children in Romania. Here we apply phylogenetic and Bayesian coalescent-based methods to reconstruct the phylodynamic patterns of HIV-1 subtype F1 in such different epidemiological settings. The phylogenetic analyses of HIV-1 subtype F1 pol sequences sampled worldwide confirmed that most sequences from Angola, Brazil and Romania segregated in country-specific monophyletic groups, while most subtype F1 sequences from Romanian children branched as a monophyletic sub-cluster (Romania-CH) nested within sequences from adults. The inferred time of the most recent common ancestor of the different subtype F1 clades were as follow: Angola=1983 (1978-1989), Brazil=1977 (1972-1981), Romania adults=1980 (1973-1987), and Romania-CH=1985 (1978-1989). All subtype F1 clades showed a demographic history best explained by a model of logistic population growth. Although the expansion phase of subtype F1 epidemic in Angola (mid 1980s to early 2000s) overlaps with the civil war period (1975-2002), the mean estimated growth rate of the Angolan F1 clade (0.49 year(-1)) was not exceptionally high, but quite similar to that estimated for the Brazilian (0.69 year(-1)) and Romanian adult (0.36 year(-1)) subtype F1 clades. The Romania-CH subtype F1 lineage, by contrast, displayed a short and explosive dissemination phase, with a median growth rate (2.47 year(-1)) much higher than that estimated for adult populations. This result supports the idea that the AIDS epidemic that affected the Romanian children was mainly caused by the spread of the HIV through highly efficient parenteral transmission networks, unlike adult populations where HIV is predominantly transmitted through sexual route. Copyright

  2. Infarto cerebral em duas crianças infectadas pelo HIV-1 Ischaemic stroke in two children with HIV-1

    Directory of Open Access Journals (Sweden)

    Cristiane Rocha

    2003-12-01

    Full Text Available Os quadros vasculares são incomuns não somente nos pacientes adultos (1% como também nas crianças. Nosso objetivo é alertar para a possibilidade da infecção pelo HIV-1 em crianças com manifestações cerebrovasculares. Das 204 crianças infectadas pelo HIV acompanhadas no Ambulatório de SIDA, descrevemos dois pacientes pré-escolares do gênero masculino, com quadro agudo febril, rebaixamento do nível de consciência, status epilepticus e hemiparesia como primeira manifestação de infecção pelo HIV-1. Nos dois casos evidenciou-se extensa isquemia em território da artéria cerebral média. Um dos pacientes evoluiu com tetraparesia espástica grave, sem contactuar com o meio, epilepsia parcial e óbito 4 anos após o diagnóstico, sem melhora do quadro neurológico. O outro paciente apresentou hemiparesia direita e afasia global, evoluindo com regressão completa do quadro neurológico. A infreqüência desses achados torna importante o seu relato, visando a inclusão da infecção pelo HIV-1 no diagnóstico diferencial das quadros cerebrovasculares na criança.Cerebral ischaemia caused by inflammatory vasculopathies has been described as a complication of human immunodeficiency virus (HIV infection. The goal of our study is to report two cases of pediatric human immunodeficiency virus infection and cerebrovascular manifestations. We describe two pre-school boys, from a group of 204 outpatients, who presented fever, seizures, hemiparesis and impairment of conscience level as a first symptom of HIV-1 infection. The serial imaging studies revealed infarction of middle cerebral artery in both cases. The first one child had a severe spastic tetraparesis and partial epilepsy and died four years later without any improvement despite of the antiretroviral therapy. The second patient had a right hemiparesis and global aphasia totally recovered two years later with antiretroviral and rehabilitation therapies. HIV infection should be included

  3. P2X1 Receptor Antagonists Inhibit HIV-1 Fusion by Blocking Virus-Coreceptor Interactions.

    Science.gov (United States)

    Giroud, Charline; Marin, Mariana; Hammonds, Jason; Spearman, Paul; Melikyan, Gregory B

    2015-09-01

    HIV-1 Env glycoprotein-mediated fusion is initiated upon sequential binding of Env to CD4 and the coreceptor CXCR4 or CCR5. Whereas these interactions are thought to be necessary and sufficient to promote HIV-1 fusion, other host factors can modulate this process. Previous studies reported potent inhibition of HIV-1 fusion by selective P2X1 receptor antagonists, including NF279, and suggested that these receptors play a role in HIV-1 entry. Here we investigated the mechanism of antiviral activity of NF279 and found that this compound does not inhibit HIV-1 fusion by preventing the activation of P2X1 channels but effectively blocks the binding of the virus to CXCR4 or CCR5. The notion of an off-target effect of NF279 on HIV-1 fusion is supported by the lack of detectable expression of P2X1 receptors in cells used in fusion experiments and by the fact that the addition of ATP or the enzymatic depletion of ATP in culture medium does not modulate viral fusion. Importantly, NF279 fails to inhibit HIV-1 fusion with cell lines and primary macrophages when added at an intermediate stage downstream of Env-CD4-coreceptor engagement. Conversely, in the presence of NF279, HIV-1 fusion is arrested downstream of CD4 binding but prior to coreceptor engagement. NF279 also antagonizes the signaling function of CCR5, CXCR4, and another chemokine receptor, as evidenced by the suppression of calcium responses elicited by specific ligands and by recombinant gp120. Collectively, our results demonstrate that NF279 is a dual HIV-1 coreceptor inhibitor that interferes with the functional engagement of CCR5 and CXCR4 by Env. Inhibition of P2X receptor activity suppresses HIV-1 fusion and replication, suggesting that P2X signaling is involved in HIV-1 entry. However, mechanistic experiments conducted in this study imply that P2X1 receptor is not expressed in target cells or involved in viral fusion. Instead, we found that inhibition of HIV-1 fusion by a specific P2X1 receptor antagonist, NF

  4. Determination of HIV-1 co-receptor usage.

    Science.gov (United States)

    Cavarelli, Mariangela; Scarlatti, Gabriella

    2014-01-01

    Human immunodeficiency virus type I (HIV-1) infects target cells through interaction with the CD4 molecule and chemokine receptors, mainly the β-chemokine receptor 5 (CCR5) and the α-chemokine receptor 4 (CXCR4). Viral isolates can be phenotypically classified based on the co-receptor they utilize to infect target cells. In this chapter, methods to determine the co-receptor usage of HIV-1 variants are described.

  5. Six Highly Conserved Targets of RNAi Revealed in HIV-1-Infected Patients from Russia Are Also Present in Many HIV-1 Strains Worldwide.

    Science.gov (United States)

    Kretova, Olga V; Fedoseeva, Daria M; Gorbacheva, Maria A; Gashnikova, Natalya M; Gashnikova, Maria P; Melnikova, Nataliya V; Chechetkin, Vladimir R; Kravatsky, Yuri V; Tchurikov, Nickolai A

    2017-09-15

    RNAi has been suggested for use in gene therapy of HIV/AIDS, but the main problem is that HIV-1 is highly variable and could escape attack from the small interfering RNAs (siRNAs) due to even single nucleotide substitutions in the potential targets. To exhaustively check the variability in selected RNA targets of HIV-1, we used ultra-deep sequencing of six regions of HIV-1 from the plasma of two independent cohorts of patients from Russia. Six RNAi targets were found that are invariable in 82%-97% of viruses in both cohorts and are located inside the domains specifying reverse transcriptase (RT), integrase, vpu, gp120, and p17. The analysis of mutation frequencies and their characteristics inside the targets suggests a likely role for APOBEC3G (apolipoprotein B mRNA editing enzyme, catalytic polypeptide-like 3G, A3G) in G-to-A mutations and a predominant effect of RT biases in the detected variability of the virus. The lowest frequency of mutations was detected in the central part of all six targets. We also discovered that the identical RNAi targets are present in many HIV-1 strains from many countries and from all continents. The data are important for both the understanding of the patterns of HIV-1 mutability and properties of RT and for the development of gene therapy approaches using RNAi for the treatment of HIV/AIDS. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

  6. Cold denaturation of the HIV-1 protease monomer

    DEFF Research Database (Denmark)

    Rösner, Heike Ilona; Caldarini, Martina; Prestel, Andreas

    2017-01-01

    The HIV-1-protease is a complex protein which in its active form adopts a homodimer dominated by -sheet structures. We have discovered a cold-denatured state of the monomeric subunit of HIV-1-protease which is populated above 0ºC and therefore directly accessible to various spectroscopic approac...

  7. HIV-1 protease-substrate coevolution in nelfinavir resistance.

    Science.gov (United States)

    Kolli, Madhavi; Ozen, Ayşegül; Kurt-Yilmaz, Nese; Schiffer, Celia A

    2014-07-01

    Resistance to various human immunodeficiency virus type 1 (HIV-1) protease inhibitors (PIs) challenges the effectiveness of therapies in treating HIV-1-infected individuals and AIDS patients. The virus accumulates mutations within the protease (PR) that render the PIs less potent. Occasionally, Gag sequences also coevolve with mutations at PR cleavage sites contributing to drug resistance. In this study, we investigated the structural basis of coevolution of the p1-p6 cleavage site with the nelfinavir (NFV) resistance D30N/N88D protease mutations by determining crystal structures of wild-type and NFV-resistant HIV-1 protease in complex with p1-p6 substrate peptide variants with L449F and/or S451N. Alterations of residue 30's interaction with the substrate are compensated by the coevolving L449F and S451N cleavage site mutations. This interdependency in the PR-p1-p6 interactions enhances intermolecular contacts and reinforces the overall fit of the substrate within the substrate envelope, likely enabling coevolution to sustain substrate recognition and cleavage in the presence of PR resistance mutations. Resistance to human immunodeficiency virus type 1 (HIV-1) protease inhibitors challenges the effectiveness of therapies in treating HIV-1-infected individuals and AIDS patients. Mutations in HIV-1 protease selected under the pressure of protease inhibitors render the inhibitors less potent. Occasionally, Gag sequences also mutate and coevolve with protease, contributing to maintenance of viral fitness and to drug resistance. In this study, we investigated the structural basis of coevolution at the Gag p1-p6 cleavage site with the nelfinavir (NFV) resistance D30N/N88D protease mutations. Our structural analysis reveals the interdependency of protease-substrate interactions and how coevolution may restore substrate recognition and cleavage in the presence of protease drug resistance mutations. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

  8. Ectopic expression of anti-HIV-1 shRNAs protects CD8{sup +} T cells modified with CD4ζ CAR from HIV-1 infection and alleviates impairment of cell proliferation

    Energy Technology Data Exchange (ETDEWEB)

    Kamata, Masakazu, E-mail: masa3k@ucla.edu [Division of Hematology-Oncology, David Geffen School of Medicine at UCLA, Los Angeles, CA (United States); Kim, Patrick Y. [Department of Microbiology, Immunology, and Molecular Genetics, David Geffen School of Medicine at UCLA, Los Angeles, CA (United States); Ng, Hwee L. [Division of Infectious Diseases, David Geffen School of Medicine at UCLA, Los Angeles, CA (United States); Ringpis, Gene-Errol E.; Kranz, Emiko; Chan, Joshua; O' Connor, Sean [Department of Microbiology, Immunology, and Molecular Genetics, David Geffen School of Medicine at UCLA, Los Angeles, CA (United States); Yang, Otto O. [Department of Microbiology, Immunology, and Molecular Genetics, David Geffen School of Medicine at UCLA, Los Angeles, CA (United States); Division of Infectious Diseases, David Geffen School of Medicine at UCLA, Los Angeles, CA (United States); UCLA AIDS Institute, Los Angeles, CA (United States); AIDS Healthcare Foundation, Los Angeles, CA (United States); Chen, Irvin S.Y. [Division of Hematology-Oncology, David Geffen School of Medicine at UCLA, Los Angeles, CA (United States); Department of Microbiology, Immunology, and Molecular Genetics, David Geffen School of Medicine at UCLA, Los Angeles, CA (United States); UCLA AIDS Institute, Los Angeles, CA (United States)

    2015-07-31

    Chimeric antigen receptors (CARs) are artificially engineered receptors that confer a desired specificity to immune effector T cells. As an HIV-1-specific CAR, CD4ζ CAR has been extensively tested in vitro as well as in clinical trials. T cells modified with this CAR mediated highly potent anti-HIV-1 activities in vitro and were well-tolerated in vivo, but exerted limited effects on viral load and reservoir size due to poor survival and/or functionality of the transduced cells in patients. We hypothesize that ectopic expression of CD4ζ on CD8{sup +} T cells renders them susceptible to HIV-1 infection, resulting in poor survival of those cells. To test this possibility, highly purified CD8{sup +} T cells were genetically modified with a CD4ζ-encoding lentiviral vector and infected with HIV-1. CD8{sup +} T cells were vulnerable to HIV-1 infection upon expression of CD4ζ as evidenced by elevated levels of p24{sup Gag} in cells and culture supernatants. Concurrently, the number of CD4ζ-modified CD8{sup +} T cells was reduced relative to control cells upon HIV-1 infection. To protect these cells from HIV-1 infection, we co-expressed two anti-HIV-1 shRNAs previously developed by our group together with CD4ζ. This combination vector was able to suppress HIV-1 infection without impairing HIV-1-dependent effector activities of CD4ζ. In addition, the number of CD4ζ-modified CD8{sup +} T cells maintained similar levels to that of the control even under HIV-1 infection. These results suggest that protecting CD4ζ-modified CD8{sup +} T cells from HIV-1 infection is required for prolonged HIV-1-specific immune surveillance. - Highlights: • Ectopic expression of CD4ζ CAR in CD8{sup +} T cells renders them susceptible to HIV-1 infection. • Co-expression of two anti-HIV-1 shRNAs protects CD4ζ CAR-modified CD8{sup +} T cells from HIV-1 infection. • Protecting CD4ζ CAR-modified CD8{sup +} T cells from HIV-1 infection suppresses its cytopathic effect.

  9. Rare HIV-1 Subtype J Genomes and a New H/U/CRF02_AG Recombinant Genome Suggests an Ancient Origin of HIV-1 in Angola.

    Science.gov (United States)

    Bártolo, Inês; Calado, Rita; Borrego, Pedro; Leitner, Thomas; Taveira, Nuno

    2016-08-01

    Angola has an extremely diverse HIV-1 epidemic fueled in part by the frequent interchange of people with the Democratic Republic of Congo (DRC) and Republic of Congo (RC). Characterization of HIV-1 strains circulating in Angola should help to better understand the origin of HIV-1 subtypes and recombinant forms and their transmission dynamics. In this study we characterize the first near full-length HIV-1 genomic sequences from HIV-1 infected individuals from Angola. Samples were obtained in 1993 from three HIV-1 infected patients living in Cabinda, Angola. Near full-length genomic sequences were obtained from virus isolates. Maximum likelihood phylogenetic tree inference and analyses of potential recombination patterns were performed to evaluate the sequence classifications and origins. Phylogenetic and recombination analyses revealed that one virus was a pure subtype J, another mostly subtype J with a small uncertain region, and the final virus was classified as a H/U/CRF02_AG recombinant. Consistent with their epidemiological data, the subtype J sequences were more closely related to each other than to other J sequences previously published. Based on the env gene, taxa from Angola occur throughout the global subtype J phylogeny. HIV-1 subtypes J and H are present in Angola at low levels since at least 1993. Low transmission efficiency and/or high recombination potential may explain their limited epidemic success in Angola and worldwide. The high diversity of rare subtypes in Angola suggests that Angola was part of the early establishment of the HIV-1 pandemic.

  10. HIV Drug Resistance-Associated Mutations in Antiretroviral Naïve HIV-1-Infected Latin American Children

    Directory of Open Access Journals (Sweden)

    Luis E. Soto-Ramirez

    2010-01-01

    Full Text Available Our goal was to describe the presence of HIV drug resistance among HIV-1-infected, antiretroviral (ARV naïve children and adolescents in Latin America and to examine resistance in these children in relation to drug exposure in the mother. Genotyping was performed on plasma samples obtained at baseline from HIV-1-infected participants in a prospective cohort study in Brazil, Argentina, and Mexico (NISDI Pediatric Study. Of 713 HIV-infected children enrolled, 69 were ARV naïve and eligible for the analysis. At enrollment, mean age was 7.3 years; 81.2% were infected with HIV perinatally. Drug resistance mutations (DRMs were detected in 6 (8.7%; 95% confidence interval 3.1–18.2% ARV-naïve subjects; none of the mothers of these 6 received ARVs during their pregnancies and none of the children received ARV prophylaxis. Reverse transcriptase mutations K70R and K70E were detected in 3 and 2 subjects, respectively; protease mutation I50 V was detected in 1 subject. Three of the 6 children with DRMs initiated ARV therapy during followup, with a good response in 2. The overall rate of primary drug resistance in this pediatric HIV-infected population was low, and no subjects had more than 1 DRM. Mutations associated with resistance to nucleoside reverse transcriptase inhibitors were the most prevalent.

  11. HIV-1 subtype A gag variability and epitope evolution.

    Science.gov (United States)

    Abidi, Syed Hani; Kalish, Marcia L; Abbas, Farhat; Rowland-Jones, Sarah; Ali, Syed

    2014-01-01

    The aim of this study was to examine the course of time-dependent evolution of HIV-1 subtype A on a global level, especially with respect to the dynamics of immunogenic HIV gag epitopes. We used a total of 1,893 HIV-1 subtype A gag sequences representing a timeline from 1985 through 2010, and 19 different countries in Africa, Europe and Asia. The phylogenetic relationship of subtype A gag and its epidemic dynamics was analysed through a Maximum Likelihood tree and Bayesian Skyline plot, genomic variability was measured in terms of G → A substitutions and Shannon entropy, and the time-dependent evolution of HIV subtype A gag epitopes was examined. Finally, to confirm observations on globally reported HIV subtype A sequences, we analysed the gag epitope data from our Kenyan, Pakistani, and Afghan cohorts, where both cohort-specific gene epitope variability and HLA restriction profiles of gag epitopes were examined. The most recent common ancestor of the HIV subtype A epidemic was estimated to be 1956 ± 1. A period of exponential growth began about 1980 and lasted for approximately 7 years, stabilized for 15 years, declined for 2-3 years, then stabilized again from about 2004. During the course of evolution, a gradual increase in genomic variability was observed that peaked in 2005-2010. We observed that the number of point mutations and novel epitopes in gag also peaked concurrently during 2005-2010. It appears that as the HIV subtype A epidemic spread globally, changing population immunogenetic pressures may have played a role in steering immune-evolution of this subtype in new directions. This trend is apparent in the genomic variability and epitope diversity of HIV-1 subtype A gag sequences.

  12. HIV-1 subtype A gag variability and epitope evolution.

    Directory of Open Access Journals (Sweden)

    Syed Hani Abidi

    Full Text Available OBJECTIVE: The aim of this study was to examine the course of time-dependent evolution of HIV-1 subtype A on a global level, especially with respect to the dynamics of immunogenic HIV gag epitopes. METHODS: We used a total of 1,893 HIV-1 subtype A gag sequences representing a timeline from 1985 through 2010, and 19 different countries in Africa, Europe and Asia. The phylogenetic relationship of subtype A gag and its epidemic dynamics was analysed through a Maximum Likelihood tree and Bayesian Skyline plot, genomic variability was measured in terms of G → A substitutions and Shannon entropy, and the time-dependent evolution of HIV subtype A gag epitopes was examined. Finally, to confirm observations on globally reported HIV subtype A sequences, we analysed the gag epitope data from our Kenyan, Pakistani, and Afghan cohorts, where both cohort-specific gene epitope variability and HLA restriction profiles of gag epitopes were examined. RESULTS: The most recent common ancestor of the HIV subtype A epidemic was estimated to be 1956 ± 1. A period of exponential growth began about 1980 and lasted for approximately 7 years, stabilized for 15 years, declined for 2-3 years, then stabilized again from about 2004. During the course of evolution, a gradual increase in genomic variability was observed that peaked in 2005-2010. We observed that the number of point mutations and novel epitopes in gag also peaked concurrently during 2005-2010. CONCLUSION: It appears that as the HIV subtype A epidemic spread globally, changing population immunogenetic pressures may have played a role in steering immune-evolution of this subtype in new directions. This trend is apparent in the genomic variability and epitope diversity of HIV-1 subtype A gag sequences.

  13. Dolutegravir reshapes the genetic diversity of HIV-1 reservoirs.

    Science.gov (United States)

    Gantner, Pierre; Lee, Guinevere Q; Rey, David; Mesplede, Thibault; Partisani, Marialuisa; Cheneau, Christine; Beck-Wirth, Geneviève; Faller, Jean-Pierre; Mohseni-Zadeh, Mahsa; Martinot, Martin; Wainberg, Mark A; Fafi-Kremer, Samira

    2018-04-01

    Better understanding of the dynamics of HIV reservoirs under ART is a critical step to achieve a functional HIV cure. Our objective was to assess the genetic diversity of archived HIV-1 DNA over 48 weeks in blood cells of individuals starting treatment with a dolutegravir-based regimen. Eighty blood samples were prospectively and longitudinally collected from 20 individuals (NCT02557997) including: acutely (n = 5) and chronically (n = 5) infected treatment-naive individuals, as well as treatment-experienced individuals who switched to a dolutegravir-based regimen and were either virologically suppressed (n = 5) or had experienced treatment failure (n = 5). The integrase and V3 loop regions of HIV-1 DNA isolated from PBMCs were analysed by pyrosequencing at baseline and weeks 4, 24 and 48. HIV-1 genetic diversity was calculated using Shannon entropy. All individuals achieved or maintained viral suppression throughout the study. A low and stable genetic diversity of archived HIV quasispecies was observed in individuals starting treatment during acute infection. A dramatic reduction of the genetic diversity was observed at week 4 of treatment in the other individuals. In these patients and despite virological suppression, a recovery of the genetic diversity of the reservoirs was observed up to 48 weeks. Viral variants bearing dolutegravir resistance-associated substitutions at integrase position 50, 124, 230 or 263 were detected in five individuals (n = 5/20, 25%) from all groups except those who were ART-failing at baseline. None of these substitutions led to virological failure. These data demonstrate that the genetic diversity of the HIV-1 reservoir is reshaped following the initiation of a dolutegravir-based regimen and strongly suggest that HIV-1 can continue to replicate despite successful treatment.

  14. Long Term Follow-up of HIV-1 Exposed Children in Nairobi

    International Nuclear Information System (INIS)

    Ndinya-Achola, J.O; Datta, P.; Maitha, G.; Embree, J.E.; Kreiss, J.K.; Achola, P.S.; Holmes, K.K.; Plummer, F.A.

    1992-01-01

    Transmission of HIV-1 from an infected mother to her infant is the major route of transmission of this infection to children. In sub-Saharan Africa where heterosexual transmission of HIV is the commonest mode of spread, high prevalence of HIV infection in women of child bearing age is bound to lead to increased paediatric AIDS as a result of vertical transmission. In recognizing these epidemiological factors, the University of Nairobi HIV-1 Perinatal Transmission and Paediatric AIDS Project was initiated in 1986. Antenatal mothers attending Pumwani Maternity Hospital were enrolled during labour and screened for HIV-1 infection by ELISA. Those reacting positive were to participate in the study. An equal number of negative controls were also recruited. The mothers and babies of both groups were followed for varying periods over the next five years. A total of 360 babies born to HIV infected mothers and 360 babies born to HIV negative mothers were examined. The mortality rate observed in the HIV-1 exposed was substantially higher than that observed in controls (RR 2.8, 95% CI 1.3-6.1). Common causes of death among infected infants were pneumonia, measles, malaria, gastroenteritis, tuberculosis, and septicaemia. The five year survival was 85% among HIV infected children. Maternal risk factors associated with transmission were marital status, duration of sexual activity and the age of the first intercourse

  15. Long Term Follow-up of HIV-1 Exposed Children in Nairobi

    Energy Technology Data Exchange (ETDEWEB)

    Ndinya-Achola, J O; Datta, P; Maitha, G [Department of Microbiology, University of Nairobi, (Kenya); Embree, J E; Kreiss, J K; Achola, P S [Health Department, Nairobi City Commission, Nairobi, (Kenya); Holmes, K K [Dept. of Medicine, Harboview Medical Centre, University of Washington, Seattle (United States); Plummer, F A [Dept. of Medical Microbiology, University of Manitoba (Canada)

    1992-05-15

    Transmission of HIV-1 from an infected mother to her infant is the major route of transmission of this infection to children. In sub-Saharan Africa where heterosexual transmission of HIV is the commonest mode of spread, high prevalence of HIV infection in women of child bearing age is bound to lead to increased paediatric AIDS as a result of vertical transmission. In recognizing these epidemiological factors, the University of Nairobi HIV-1 Perinatal Transmission and Paediatric AIDS Project was initiated in 1986. Antenatal mothers attending Pumwani Maternity Hospital were enrolled during labour and screened for HIV-1 infection by ELISA. Those reacting positive were to participate in the study. An equal number of negative controls were also recruited. The mothers and babies of both groups were followed for varying periods over the next five years. A total of 360 babies born to HIV infected mothers and 360 babies born to HIV negative mothers were examined. The mortality rate observed in the HIV-1 exposed was substantially higher than that observed in controls (RR 2.8, 95% CI 1.3-6.1). Common causes of death among infected infants were pneumonia, measles, malaria, gastroenteritis, tuberculosis, and septicaemia. The five year survival was 85% among HIV infected children. Maternal risk factors associated with transmission were marital status, duration of sexual activity and the age of the first intercourse.

  16. Molecular and phylogenetic analysis of HIV-1 variants circulating in Italy

    Directory of Open Access Journals (Sweden)

    Sbreglia Costanza

    2008-10-01

    Full Text Available Abstract Objective The continuous identification of HIV-1 non-B subtypes and recombinant forms in Italy indicates the need of constant molecular epidemiology survey of genetic forms circulating and transmitted in the resident population. Methods The distribution of HIV-1 subtypes has been evaluated in 25 seropositive individuals residing in Italy, most of whom were infected through a sexual route during the 1995–2005 period. Each sample has been characterized by detailed molecular and phylogenetic analyses. Results 18 of the 25 samples were positive at HIV-1 PCR amplification. Three samples showed a nucleotide divergence compatible with a non-B subtype classification. The phylogenetic analysis, performed on both HIV-1 env and gag regions, confirms the molecular sub-typing prediction, given that 1 sample falls into the C subtype and 2 into the G subtype. The B subtype isolates show high levels of intra-subtype nucleotide divergence, compatible with a long-lasting epidemic and a progressive HIV-1 molecular diversification. Conclusion The Italian HIV-1 epidemic is still mostly attributable to the B subtype, regardless the transmission route, which shows an increasing nucleotide heterogeneity. Heterosexual transmission and the interracial blending, however, are slowly introducing novel HIV-1 subtypes. Therefore, a molecular monitoring is needed to follow the constant evolution of the HIV-1 epidemic.

  17. NF-kappaB and p53 are the dominant apoptosis-inducing transcription factors elicited by the HIV-1 envelope.

    Science.gov (United States)

    Perfettini, Jean-Luc; Roumier, Thomas; Castedo, Maria; Larochette, Nathanael; Boya, Patricia; Raynal, Brigitte; Lazar, Vladimir; Ciccosanti, Fabiola; Nardacci, Roberta; Penninger, Josef; Piacentini, Mauro; Kroemer, Guido

    2004-03-01

    The coculture of cells expressing the HIV-1 envelope glycoprotein complex (Env) with cells expressing CD4 results into cell fusion, deregulated mitosis, and subsequent cell death. Here, we show that NF-kappaB, p53, and AP1 are activated in Env-elicited apoptosis. The nuclear factor kappaB (NF-kappaB) super repressor had an antimitotic and antiapoptotic effect and prevented the Env-elicited phosphorylation of p53 on serine 15 and 46, as well as the activation of AP1. Transfection with dominant-negative p53 abolished apoptosis and AP1 activation. Signs of NF-kappaB and p53 activation were also detected in lymph node biopsies from HIV-1-infected individuals. Microarrays revealed that most (85%) of the transcriptional effects of HIV-1 Env were blocked by the p53 inhibitor pifithrin-alpha. Macroarrays led to the identification of several Env-elicited, p53-dependent proapoptotic transcripts, in particular Puma, a proapoptotic "BH3-only" protein from the Bcl-2 family known to activate Bax/Bak. Down modulation of Puma by antisense oligonucleotides, as well as RNA interference of Bax and Bak, prevented Env-induced apoptosis. HIV-1-infected primary lymphoblasts up-regulated Puma in vitro. Moreover, circulating CD4+ lymphocytes from untreated, HIV-1-infected donors contained enhanced amounts of Puma protein, and these elevated Puma levels dropped upon antiretroviral therapy. Altogether, these data indicate that NF-kappaB and p53 cooperate as the dominant proapoptotic transcription factors participating in HIV-1 infection.

  18. Platelet-derived growth factor (PDGF-BB-mediated induction of monocyte chemoattractant protein 1 in human astrocytes: implications for HIV-associated neuroinflammation

    Directory of Open Access Journals (Sweden)

    Bethel-Brown Crystal

    2012-12-01

    Full Text Available Abstract Chemokine (C-C motif ligand 2, also known as monocyte chemoattractant protein 1 (MCP-1 is an important factor for the pathogenesis of HIV-associated neurocognitive disorders (HAND. The mechanisms of MCP-1-mediated neuropathogenesis, in part, revolve around its neuroinflammatory role and the recruitment of monocytes into the central nervous system (CNS via the disrupted blood-brain barrier (BBB. We have previously demonstrated that HIV-1/HIV-1 Tat upregulate platelet-derived growth factor (PDGF-BB, a known cerebrovascular permeant; subsequently, the present study was aimed at exploring the regulation of MCP-1 by PDGF-BB in astrocytes with implications in HAND. Specifically, the data herein demonstrate that exposure of human astrocytes to HIV-1 LAI elevated PDGF-B and MCP-1 levels. Furthermore, treating astrocytes with the human recombinant PDGF-BB protein significantly increased the production and release of MCP-1 at both the RNA and protein levels. MCP-1 induction was regulated by activation of extracellular-signal-regulated kinase (ERK1/2, c-Jun N-terminal kinase (JNK and p38 mitogen-activated protein (MAP kinases and phosphatidylinositol 3-kinase (PI3K/Akt pathways and the downstream transcription factor, nuclear factor κB (NFκB. Chromatin immunoprecipitation (ChIP assays demonstrated increased binding of NFκB to the human MCP-1 promoter following PDGF-BB exposure. Conditioned media from PDGF-BB-treated astrocytes increased monocyte transmigration through human brain microvascular endothelial cells (HBMECs, an effect that was blocked by STI-571, a tyrosine kinase inhibitor (PDGF receptor (PDGF-R blocker. PDGF-BB-mediated release of MCP-1 was critical for increased permeability in an in vitro BBB model as evidenced by blocking antibody assays. Since MCP-1 is linked to disease severity, understanding its modulation by PDGF-BB could aid in understanding the proinflammatory responses in HAND. These results suggest that astrocyte

  19. HIV-1 Envelope Glycoprotein Trafficking through the Endosomal Recycling Compartment Is Required for Particle Incorporation.

    Science.gov (United States)

    Kirschman, Junghwa; Qi, Mingli; Ding, Lingmei; Hammonds, Jason; Dienger-Stambaugh, Krista; Wang, Jaang-Jiun; Lapierre, Lynne A; Goldenring, James R; Spearman, Paul

    2018-03-01

    The human immunodeficiency virus type 1 (HIV-1) envelope glycoprotein (Env) encodes specific trafficking signals within its long cytoplasmic tail (CT) that regulate incorporation into HIV-1 particles. Rab11-family interacting protein 1C (FIP1C) and Rab14 are host trafficking factors required for Env particle incorporation, suggesting that Env undergoes sorting from the endosomal recycling compartment (ERC) to the site of particle assembly on the plasma membrane. We disrupted outward sorting from the ERC by expressing a C-terminal fragment of FIP1C (FIP1C 560-649 ) and examined the consequences on Env trafficking and incorporation into particles. FIP1C 560-649 reduced cell surface levels of Env and prevented its incorporation into HIV-1 particles. Remarkably, Env was trapped in an exaggerated perinuclear ERC in a CT-dependent manner. Mutation of either the Yxxϕ endocytic motif or the YW 795 motif in the CT prevented Env trapping in the ERC and restored incorporation into particles. In contrast, simian immunodeficiency virus SIVmac239 Env was not retained in the ERC, while substitution of the HIV-1 CT for the SIV CT resulted in SIV Env retention in this compartment. These results provide the first direct evidence that Env traffics through the ERC and support a model whereby HIV-1 Env is specifically targeted to the ERC prior to FIP1C- and CT-dependent outward sorting to the particle assembly site on the plasma membrane. IMPORTANCE The HIV envelope protein is an essential component of the viral particle. While many aspects of envelope protein structure and function have been established, the pathway it follows in the cell prior to reaching the site of particle assembly is not well understood. The envelope protein has a very long cytoplasmic tail that interacts with the host cell trafficking machinery. Here, we utilized a truncated form of the trafficking adaptor FIP1C protein to arrest the intracellular transport of the envelope protein, demonstrating that it becomes

  20. Vaginalmycosis and HIV-1 infection in Kaduna, Nigeria. | Eni ...

    African Journals Online (AJOL)

    ... mycosis in HIV-1positive women and managed accordingly. Proper management of these two conditions will improve reproductive health of women in Nigeria. Keywords: Vaginal mycosis, Genital candidiasis, Reproductive health: Candida albicans: HIV-1 infection. Journal of Biomedical Investigation Vol. 3 (1) 2005: pp.

  1. Performance evaluation of the Bio-Rad Laboratories GS HIV Combo Ag/Ab EIA, a 4th generation HIV assay for the simultaneous detection of HIV p24 antigen and antibodies to HIV-1 (groups M and O) and HIV-2 in human serum or plasma.

    Science.gov (United States)

    Bentsen, Christopher; McLaughlin, Lisa; Mitchell, Elizabeth; Ferrera, Carol; Liska, Sally; Myers, Robert; Peel, Sheila; Swenson, Paul; Gadelle, Stephane; Shriver, M Kathleen

    2011-12-01

    A multi-center study was conducted to evaluate the Bio-Rad GS HIV Combo Ag/Ab EIA, a 4th generation HIV-1/HIV-2 assay for the simultaneous detection of HIV p24 antigen and antibodies to HIV-1 (groups M and O) and HIV-2 in human serum or plasma in adult and pediatric populations. The objectives of the study were to assess assay performance for the detection of acute HIV infections; sensitivity in known HIV positive samples; percent agreement with HIV status; specificity in low and high risk individuals of unknown HIV status; and to compare assay performance to a 3rd generation HIV assay. The evaluation included testing 9150 samples at four U.S. clinical trial sites, using three kit lots. Unlinked samples were from routine testing, repositories or purchased from vendors. GS HIV Combo Ag/Ab EIA detection in samples from individuals in two separate populations with acute HIV infection was 95.2% (20/21) and 86.4% (38/44). Sensitivity was 100% (1603/1603) in known antibody positive [HIV-1 Groups M and O, and HIV-2] samples. HIV p24 antigen detection was 100% (53/53) in HIV-1 culture supernatants. HIV-1 seroconversion panel detection improved by a range of 0-20 days compared to a 3rd generation HIV test. Specificity was 99.9% (5989/5996) in low risk, 99.9% (959/960) in high risk and 100% (100/100) in pediatric populations. The GS HIV Combo Ag/Ab EIA significantly reduced the diagnostic window when compared to the 3rd generation screening assay, enabling earlier diagnosis of HIV infection. The performance parameters of the Bio-Rad GS HIV Combo Ag/Ab EIA are well suited for use in HIV diagnostic settings. Copyright © 2011 Elsevier B.V. All rights reserved.

  2. Inhibition of Non Canonical HIV-1 Tat Secretion Through the Cellular Na+,K+-ATPase Blocks HIV-1 Infection

    Directory of Open Access Journals (Sweden)

    Silvia Agostini

    2017-07-01

    Full Text Available Besides its essential role in the activation of HIV-1 gene expression, the viral Tat protein has the unusual property of trafficking in and out of cells. In contrast to Tat internalization, the mechanism involved in extracellular Tat release has so far remained elusive. Here we show that Tat secretion occurs through a Golgi-independent pathway requiring binding of Tat with three short, non-consecutive intracytoplasmic loops at the C-terminus of the cellular Na+,K+-ATPase pump alpha subunit. Ouabain, a pump inhibitor, blocked this interaction and prevented Tat secretion; virions produced in the presence of this drug were less infectious, consistent the capacity of virion-associated Tat to increase HIV-1 infectivity. Treatment of CD4+ T-cells with short peptides corresponding to the Tat-binding regions of the pump alpha subunit impaired extracellular Tat release and blocked HIV-1 replication. Thus, non canonical, extracellular Tat secretion is essential for viral infectivity.

  3. Dynamics of HIV-1 RNA Near the Plasma Membrane during Virus Assembly.

    Science.gov (United States)

    Sardo, Luca; Hatch, Steven C; Chen, Jianbo; Nikolaitchik, Olga; Burdick, Ryan C; Chen, De; Westlake, Christopher J; Lockett, Stephen; Pathak, Vinay K; Hu, Wei-Shau

    2015-11-01

    To increase our understanding of the events that lead to HIV-1 genome packaging, we examined the dynamics of viral RNA and Gag-RNA interactions near the plasma membrane by using total internal reflection fluorescence microscopy. We labeled HIV-1 RNA with a photoconvertible Eos protein via an RNA-binding protein that recognizes stem-loop sequences engineered into the viral genome. Near-UV light exposure causes an irreversible structural change in Eos and alters its emitted fluorescence from green to red. We studied the dynamics of HIV-1 RNA by photoconverting Eos near the plasma membrane, and we monitored the population of photoconverted red-Eos-labeled RNA signals over time. We found that in the absence of Gag, most of the HIV-1 RNAs stayed near the plasma membrane transiently, for a few minutes. The presence of Gag significantly increased the time that RNAs stayed near the plasma membrane: most of the RNAs were still detected after 30 min. We then quantified the proportion of HIV-1 RNAs near the plasma membrane that were packaged into assembling viral complexes. By tagging Gag with blue fluorescent protein, we observed that only a portion, ∼13 to 34%, of the HIV-1 RNAs that reached the membrane were recruited into assembling particles in an hour, and the frequency of HIV-1 RNA packaging varied with the Gag expression level. Our studies reveal the HIV-1 RNA dynamics on the plasma membrane and the efficiency of RNA recruitment and provide insights into the events leading to the generation of infectious HIV-1 virions. Nascent HIV-1 particles assemble on plasma membranes. During the assembly process, HIV-1 RNA genomes must be encapsidated into viral complexes to generate infectious particles. To gain insights into the RNA packaging and virus assembly mechanisms, we labeled and monitored the HIV-1 RNA signals near the plasma membrane. Our results showed that most of the HIV-1 RNAs stayed near the plasma membrane for only a few minutes in the absence of Gag, whereas

  4. The Effects of the Recombinant CCR5 T4 Lysozyme Fusion Protein on HIV-1 Infection.

    Directory of Open Access Journals (Sweden)

    Qingwen Jin

    Full Text Available Insertion of T4 lysozyme (T4L into the GPCR successfully enhanced GPCR protein stability and solubilization. However, the biological functions of the recombinant GPCR protein have not been analyzed.We engineered the CCR5-T4L mutant and expressed and purified the soluble recombinant protein using an E.coli expression system. The antiviral effects of this recombinant protein in THP-1 cell lines, primary human macrophages, and PBMCs from different donors were investigated. We also explored the possible mechanisms underlying the observed antiviral effects.Our data showed the biphasic inhibitory and promotion effects of different concentrations of soluble recombinant CCR5-T4L protein on R5 tropic human immunodeficiency virus-1 (HIV-1 infection in THP-1 cell lines, human macrophages, and PBMCs from clinical isolates. We demonstrated that soluble recombinant CCR5-T4L acts as a HIV-1 co-receptor, interacts with wild type CCR5, down-regulates the surface CCR5 expression in human macrophages, and interacts with CCL5 to inhibit macrophage migration. Using binding assays, we further determined that recombinant CCR5-T4L and [125I]-CCL5 compete for the same binding site on wild type CCR5.Our results suggest that recombinant CCR5-T4L protein marginally promotes HIV-1 infection at low concentrations and markedly inhibits infection at higher concentrations. This recombinant protein may be helpful in the future development of anti-HIV-1 therapeutic agents.

  5. The latest evidence for possible HIV-1 curative strategies.

    Science.gov (United States)

    Pham, Hanh Thi; Mesplède, Thibault

    2018-01-01

    Human immunodeficiency virus type 1 (HIV-1) infection remains a major health issue worldwide. In developed countries, antiretroviral therapy has extended its reach from treatment of people living with HIV-1 to post-exposure prophylaxis, treatment as prevention, and, more recently, pre-exposure prophylaxis. These healthcare strategies offer the epidemiological tools to curve the epidemic in rich settings and will be concomitantly implemented in developing countries. One of the remaining challenges is to identify an efficacious curative strategy. This review manuscript will focus on some of the current curative strategies aiming at providing a sterilizing or functional cure to HIV-1-positive individuals. These include the following: early treatment initiation in post-treatment controllers as a long-term HIV-1 remission strategy, latency reversal, gene editing with or without stem cell transplantation, and antibodies against either the viral envelope protein or the host integrin α4β7.

  6. Mechanisms for Cell-to-Cell Transmission of HIV-1

    Science.gov (United States)

    Bracq, Lucie; Xie, Maorong; Benichou, Serge; Bouchet, Jérôme

    2018-01-01

    While HIV-1 infection of target cells with cell-free viral particles has been largely documented, intercellular transmission through direct cell-to-cell contact may be a predominant mode of propagation in host. To spread, HIV-1 infects cells of the immune system and takes advantage of their specific particularities and functions. Subversion of intercellular communication allows to improve HIV-1 replication through a multiplicity of intercellular structures and membrane protrusions, like tunneling nanotubes, filopodia, or lamellipodia-like structures involved in the formation of the virological synapse. Other features of immune cells, like the immunological synapse or the phagocytosis of infected cells are hijacked by HIV-1 and used as gateways to infect target cells. Finally, HIV-1 reuses its fusogenic capacity to provoke fusion between infected donor cells and target cells, and to form infected syncytia with high capacity of viral production and improved capacities of motility or survival. All these modes of cell-to-cell transfer are now considered as viral mechanisms to escape immune system and antiretroviral therapies, and could be involved in the establishment of persistent virus reservoirs in different host tissues. PMID:29515578

  7. Options to Expand HIV Viral Load Testing in South Africa: Evaluation of the GeneXpert® HIV-1 Viral Load Assay.

    Directory of Open Access Journals (Sweden)

    Natasha Gous

    Full Text Available Expansion of HIV viral load (VL testing services are required to meet increased targets for monitoring patients on antiretroviral treatment. South Africa currently tests >4million VLs per annum in 16 highly centralised, automated high-throughput laboratories. The Xpert HIV-1 VL assay (Cepheid was evaluated against in-country predicates, the Roche Cobas Taqmanv2 and Abbott HIV-1RT, to investigate options for expanding VL testing using GeneXpert's random access, polyvalent capabilities and already established footprint in South Africa with the Xpert MTB/RIF assay (207 sites. Additionally, the performance of Xpert HIV-1VL on alternative, off-label specimen types, Dried Blood Spots (DBS and whole blood, was investigated.Precision, accuracy (agreement and clinical misclassification (1000cp/ml of Xpert HIV-1VL plasma was compared to Taqmanv2 (n = 155 and Abbott HIV-1 RT (n = 145. Misclassification of Xpert HIV-1VL was further tested on DBS (n = 145 and whole blood (n = 147.Xpert HIV-1VL demonstrated 100% concordance with predicate platforms on a standardised frozen, plasma panel (n = 42 and low overall percentage similarity CV of 1.5% and 0.9% compared to Taqmanv2 and Abbott HIV-1 RT, respectively. On paired plasma clinical specimens, Xpert HIV-1VL had low bias (SD 0.32-0.37logcp/ml and 3% misclassification at the 1000cp/ml threshold compared to Taqmanv2 (fresh and Abbott HIV-1 RT (frozen, respectively. Xpert HIV-1VL on whole blood and DBS increased misclassification (upward by up to 14% with increased invalid rate. All specimen testing was easy to perform and compatible with concurrent Xpert MTB/RIF Tuberculosis testing on the same instrument.The Xpert HIV-1VL on plasma can be used interchangeably with existing predicate platforms in South Africa. Whole blood and DBS testing requires further investigation, but polyvalency of the GeneXpert offers a solution to extending VL testing services.

  8. Contraceptive method and pregnancy incidence among women in HIV-1-serodiscordant partnerships.

    Science.gov (United States)

    Ngure, Kenneth; Heffron, Renee; Mugo, Nelly R; Celum, Connie; Cohen, Craig R; Odoyo, Josephine; Rees, Helen; Kiarie, James N; Were, Edwin; Baeten, Jared M

    2012-02-20

    Effective contraception reduces unintended pregnancies and is a central strategy to reduce vertical HIV-1 transmission for HIV-1-infected women. Among 2269 HIV-1-seropositive and 1085-seronegative women from seven African countries who were members of HIV-1-serodiscordant heterosexual partnerships and who were participating in an HIV-1 prevention clinical trial, we assessed pregnancy incidence according to contraceptive method using multivariate Andersen-Gill analysis. Compared with women using no contraceptive method, pregnancy incidence was significantly reduced among HIV-1-seropositive and HIV-1-seronegative women using injectable contraception [adjusted hazard ratio (aHR) 0.24, P = 0.001 and aHR 0.25, P pregnancy risk only among HIV-1-seropositive women (aHR 0.51, P = 0.004) but not seronegative women (aHR 0.64, P = 0.3), and, for both seropositive and seronegative women, oral contraceptive pill users were more likely to become pregnant than injectable contraceptive users (aHR 2.22, P = 0.01 for HIV-1-seropositive women and aHR 2.65, P = 0.09 for HIV-1-seronegative women). Condoms, when reported as being used as the primary contraceptive method, marginally reduced pregnancy incidence (aHR 0.85, P = 0.1 for seropositive women and aHR 0.67, P = 0.02 for seronegative women). There were no pregnancies among women using intrauterine devices, implantable methods or who had undergone surgical sterilization, although these methods were used relatively infrequently. Family planning programs and HIV-1 prevention trials need innovative ways to motivate uptake and sustained use of longer acting, less user-dependent contraception for women who do not desire pregnancy.

  9. Cyclophilin A potentiates TRIM5α inhibition of HIV-1 nuclear import without promoting TRIM5α binding to the viral capsid.

    Directory of Open Access Journals (Sweden)

    Mallori Burse

    Full Text Available The host immunophilin cyclophilin A (CypA binds to the capsid protein (CA of HIV-1 and regulates its infectivity. Depending on the target cell type, CypA can either promote or inhibit HIV-1 infection. The ability of CypA to promote HIV-1 infection has been extensively studied and linked to several steps in early replication including uncoating, reverse transcription and nuclear import. By contrast, the mechanism by which CypA inhibits infection is less well understood. We investigated the mechanism by which CypA potentiates restriction of HIV-1 by the tripartite motif-containing protein 5 (TRIM5α. Depletion of TRIM5α in the African green monkey cell line Vero, resulted in a loss of inhibition of infection by CypA, demonstrating that inhibition by CypA is mediated by TRIM5α. Complementary genetic and biochemical assays failed to demonstrate an ability of CypA to promote binding of TRIM5α to the viral capsid. TRIM5α inhibits HIV-1 reverse transcription in a proteasome-dependent manner; however, we observed that inhibition of proteasome activity did not reduce the ability of CypA to inhibit infection, suggesting that CypA acts at a step after reverse transcription. Accordingly, we observed a CypA-dependent reduction in the accumulation of nuclear HIV-1 DNA, indicating that CypA specifically promotes TRIM5α inhibition of HIV-1 nuclear import. We also observed that the ability of CypA to inhibit HIV-1 infection is abolished by amino acid substitutions within the conserved CPSF6-binding surface in CA. Our results indicate that CypA inhibits HIV-1 infection in Vero cells not by promoting TRIM5α binding to the capsid but by blocking nuclear import of the HIV-1 preintegration complex.

  10. Broad and potent immune responses to a low dose intradermal HIV-1 DNA boosted with HIV-1 recombinant MVA among healthy adults in Tanzania☆,☆☆

    Science.gov (United States)

    Bakari, Muhammad; Aboud, Said; Nilsson, Charlotta; Francis, Joel; Buma, Deus; Moshiro, Candida; Aris, Eric A.; Lyamuya, Eligius F.; Janabi, Mohamed; Godoy-Ramirez, Karina; Joachim, Agricola; Polonis, Victoria R.; Bråve, Andreas; Earl, Patricia; Robb, Merlin; Marovich, Mary; Wahren, Britta; Pallangyo, Kisali; Biberfeld, Gunnel; Mhalu, Fred; Sandström, Eric

    2016-01-01

    Background We conducted a phase I/II randomized placebo-controlled trial with the aim of exploring whether priming with a low intradermal dose of a multiclade, multigene HIV-1 DNA vaccine could improve the immunogenicity of the same vaccine given intramuscularly prior to boosting with a heterologous HIV-1 MVA among healthy adults in Dar es Salaam, Tanzania. Methods Sixty HIV-uninfected volunteers were randomized to receive DNA plasmid vaccine 1 mg intradermally (id), n = 20, or 3.8 mg intramuscularly (im), n = 20, or placebo, n = 20, using a needle-free injection device. DNA plasmids encoding HIV-1 genes gp160 subtype A, B, C; rev B; p17/p24 gag A, B and Rtmut B were given at weeks 0, 4 and 12. Recombinant MVA (108 pfu) expressing HIV-1 Env, Gag, Pol of CRF01_AE or placebo was administered im at month 9 and 21. Results The vaccines were well tolerated. Two weeks after the third HIV-DNA injection, 22/38 (58%) vaccinees had IFN-γ ELISpot responses to Gag. Two weeks after the first HIV-MVA boost all 35 (100%) vaccinees responded to Gag and 31 (89%) to Env. Two to four weeks after the second HIV-MVA boost, 28/29 (97%) vaccinees had IFN-γ ELISpot responses, 27 (93%) to Gag and 23 (79%) to Env. The id-primed recipients had significantly higher responses to Env than im recipients. Intracellular cytokine staining for Gag-specific IFN-γ/IL-2 production showed both CD8+ and CD4+ T cell responses. All vaccinees had HIV-specific lymphoproliferative responses. All vaccinees reacted in diagnostic HIV serological tests and 26/29 (90%) had antibodies against gp160 after the second HIV-MVA boost. Furthermore, while all of 29 vaccinee sera were negative for neutralizing antibodies against clade B, C and CRF01 AE pseudoviruses in the TZM-bl neutralization assay, in a PBMC assay, the response rate ranged from 31% to 83% positives, depending upon the clade B or CRF01_AE virus tested. This vaccine approach is safe and highly immunogenic. Low dose, id HIV-DNA priming elicited higher

  11. Histone deacetylase inhibitors for purging HIV-1 from the latent reservoir.

    NARCIS (Netherlands)

    Matalon, S.; Rasmussen, T.A.; Dinarello, C.A.

    2011-01-01

    A reservoir of latently infected memory CD4(+) T cells is believed to be the source of HIV-1 reemergence after discontinuation of antiretroviral therapy. HIV-1 eradication may depend on depletion of this reservoir. Integrated HIV-1 is inaccessible for expression, in part because of histone

  12. Occurrence of transmitted HIV-1 drug resistance among Drug-naïve pregnant women in selected HIV-care centres in Ghana.

    Science.gov (United States)

    Martin-Odoom, Alexander; Adiku, Theophilus; Delgado, Elena; Lartey, Margaret; Ampofo, William K

    2017-03-01

    Access to antiretroviral therapy in Ghana has been scaled up across the country over the last decade. This study sought to determine the occurrence of transmitted HIV-1 drug resistance in pregnant HIV-1 positive women yet to initiate antiretroviral therapy at selected HIV Care Centres in Ghana. Plasma specimens from twenty-six (26) HIV seropositive pregnant women who were less than 28weeks pregnant with their first pregnancy and ART naïve were collected from selected HIV care centres in three (3) regions in Ghana. Genotypic testing was done for the reverse transcriptase gene and the sequences generated were analyzed for HIV-1 drug resistance mutations using the Stanford University HIV Drug Resistance Database. Resistance mutations associated with the reverse transcriptase gene were detected in 4 (15.4%) of the participants. At least one major drug resistance mutation in the reverse transcriptase gene was found in 3 (11.5%) of the women. The detection of transmitted HIV-1 drug resistance in this drug-naïve group in two regional HIV care sites is an indication of the need for renewed action in monitoring the emergence of transmitted HIV-1 drug resistance in Ghana. None declared.

  13. Inhibition of human immunodeficiency virus 1 (HIV-1) and herpes simplex virus 1 (HSV-1) infectivity with a broad range of lectins

    DEFF Research Database (Denmark)

    Hansen, J E; Nielsen, C; Vestergaard, B F

    1991-01-01

    Five lectins with specificity for N- and O-linked oligosaccharides were examined for inhibition of HIV-1 and HSV-1 infectivity in vitro. HIV-1 isolate HTLVIIIB was preincubated with lectin and subsequently inoculated onto MT-4 cells. Lectins specific for N-linked oligosaccharides blocked HIV infe...

  14. Broadly neutralizing antibodies for treatment and prevention of HIV-1 infection.

    Science.gov (United States)

    Cohen, Yehuda Z; Caskey, Marina

    2018-04-24

    Several anti-HIV-1 broadly neutralizing antibodies (bNAbs) with exceptional breadth and potency that target different HIV-1 envelope epitopes have been identified. bNAbs are an attractive new strategy for HIV-1 prevention and therapy, and potentially, for long-term remission or cure. Here, we discuss findings from early clinical studies that have evaluated these novel bNAbs. Phase 1 studies of bNAbs targeting two distinct HIV-1 envelope epitopes have demonstrated their favorable safety and pharmacokinetic profile. Single bNAb infusions led to significant, but transient, decline in viremia with selection of escape variants. A single bNAb also delayed viral rebound in ART-treated participants who discontinued ART. Importantly, in-vivo efficacy was related to antibody potency and to the level of preexisting resistance. Studies in animal models showed that bNAbs can clear HIV-infected cells and modulate host immune responses. These findings suggest that bNAbs may target the latent HIV reservoir in humans and could contribute to long-term remission of HIV-1 infection. bNAbs may offer advantages over traditional ART for both the prevention and treatment of HIV-1 infection. In addition, bNAbs may target the latent viral reservoir. bNAb combinations and bNAbs engineered for prolonged half-life and increased potency are currently undergoing clinical evaluation.

  15. Compartmentalization of the gut viral reservoir in HIV-1 infected patients

    Directory of Open Access Journals (Sweden)

    Grant Tannika

    2007-12-01

    Full Text Available Abstract Background Recently there has been an increasing interest and appreciation for the gut as both a viral reservoir as well as an important host-pathogen interface in human immunodefiency virus type 1 (HIV-1 infection. The gut associated lymphoid tissue (GALT is the largest lymphoid organ infected by HIV-1. In this study we examined if different HIV-1 quasispecies are found in different parts of the gut of HIV-1 infected individuals. Results Gut biopsies (esophagus, stomach, duodenum and colorectum were obtained from eight HIV-1 infected preHAART (highly active antiretroviral therapy patients. HIV-1 Nef and Reverse transcriptase (RT encoding sequences were obtained through nested PCR amplification from DNA isolated from the gut biopsy tissues. The PCR fragments were cloned and sequenced. The resulting sequences were subjected to various phylogenetic analyses. Expression of the nef gene and viral RNA in the different gut tissues was determined using real-time RT-PCR. Phylogenetic analysis of the Nef protein-encoding region revealed compartmentalization of viral replication in the gut within patients. Viral diversity in both the Nef and RT encoding region varied in different parts of the gut. Moreover, increased nef gene expression (p Conclusion Our results indicated that different HIV-1 quasispecies populate different parts of the gut, and that viral replication in the gut is compartmentalized. These observations underscore the importance of the gut as a host-pathogen interface in HIV-1 infection.

  16. Effect of HIV-1 infection on malaria treatment outcome in Ugandan ...

    African Journals Online (AJOL)

    Background: Malaria and HIV-1 infection cause significant morbidity and mortality in sub-Saharan Africa. HIV-1 increases risk for malaria with the risk increasing as immunity declines.The effect of HIV-1 infection on antimalarial treatment outcome is still inconclusive. Objective: To compare antimalarial treatment outcome ...

  17. Evolution of Neutralization Response in HIV-1 Subtype C-Infected Individuals Exhibiting Broad Cross-Clade Neutralization of HIV-1 Strains

    Directory of Open Access Journals (Sweden)

    Narayanaiah Cheedarla

    2018-03-01

    Full Text Available Strain-specific neutralizing antibodies develop in all human immunodeficiency virus type 1 (HIV-1-infected individuals. However, only 10–30% of infected individuals produce broadly neutralizing antibodies (bNAbs. Identification and characterization of these bNAbs and understanding their evolution dynamics are critical for obtaining useful clues for the development of an effective HIV vaccine. Very recently, we published a study in which we identified 12 HIV-1 subtype C-infected individuals from India whose plasma showed potent and broad cross-clade neutralization (BCN ability (1. In the present study, we report our findings on the evolution of host bNAb response over a period of 4 years in a subset of these individuals. Three of the five individuals (NAB033, NAB059, and NAB065 demonstrated a significant increase (p < 0.05 in potency. Interestingly, two of the three samples also showed a significant increase in CD4 binding site-specific antibody response, maintained stable CD4+ T cell counts (>350 cells/mm3 and continued to remain ART-naïve for more than 10 years after initial diagnosis, implying a strong clinical correlation with the development and evolution of broadly neutralizing antibody response against HIV-1.

  18. GRL-09510, a Unique P2-Crown-Tetrahydrofuranylurethane -Containing HIV-1 Protease Inhibitor, Maintains Its Favorable Antiviral Activity against Highly-Drug-Resistant HIV-1 Variants in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Amano, Masayuki; Miguel Salcedo-Gómez, Pedro; Yedidi, Ravikiran S.; Delino, Nicole S.; Nakata, Hirotomo; Venkateswara Rao, Kalapala; Ghosh, Arun K.; Mitsuya, Hiroaki

    2017-09-25

    We report that GRL-09510, a novel HIV-1 protease inhibitor (PI) containing a newly-generated P2-crown-tetrahydrofuranylurethane (Crwn-THF), a P2'-methoxybenzene, and a sulfonamide isostere, is highly active against laboratory and primary clinical HIV-1 isolates (EC50: 0.0014–0.0028 μM) with minimal cytotoxicity (CC50: 39.0 μM). Similarly, GRL-09510 efficiently blocked the replication of HIV-1NL4-3 variants, which were capable of propagating at high-concentrations of atazanavir, lopinavir, and amprenavir (APV). GRL-09510 was also potent against multi-drug-resistant clinical HIV-1 variants and HIV-2ROD. Under the selection condition, where HIV-1NL4-3 rapidly acquired significant resistance to APV, an integrase inhibitor raltegravir, and a GRL-09510 congener (GRL-09610), no variants highly resistant against GRL-09510 emerged over long-term in vitro passage of the virus. Crystallographic analysis demonstrated that the Crwn-THF moiety of GRL-09510 forms strong hydrogen-bond-interactions with HIV-1 protease (PR) active-site amino acids and is bulkier with a larger contact surface, making greater van der Waals contacts with PR than the bis-THF moiety of darunavir. The present data demonstrate that GRL-09510 has favorable features for treating patients infected with wild-type and/or multi-drug-resistant HIV-1 variants, that the newly generated P2-Crwn-THF moiety confers highly desirable anti-HIV-1 potency. The use of the novel Crwn-THF moiety sheds lights in the design of novel PIs.

  19. Particle-based vaccines for HIV-1 infection.

    Science.gov (United States)

    Young, Kelly R; Ross, Ted M

    2003-06-01

    The use of live-attenuated viruses as vaccines has been successful for the control of viral infections. However, the development of an effective vaccine against the human immunodeficiency virus (HIV) has proven to be a challenge. HIV infects cells of the immune system and results in a severe immunodeficiency. In addition, the ability of the virus to adapt to immune pressure and the ability to reside in an integrated form in host cells present hurdles for vaccinologists to overcome. A particle-based vaccine strategy has promise for eliciting high titer, long-lived, immune responses to a diverse number of viral epitopes from different HIV antigens. Live-attenuated viruses are effective at generating both cellular and humoral immunity, however, a live-attenuated vaccine for HIV is problematic. The possibility of a live-attenuated vaccine to revert to a pathogenic form or recombine with a wild-type or defective virus in an infected individual is a drawback to this approach. Therefore, these vaccines are currently only being tested in non-human primate models. Live-attenuated vaccines are effective in stimulating immunity, however challenged animals rarely clear viral infection and the degree of attenuation directly correlates with the protection of animals from disease. Another particle-based vaccine approach for HIV involves the use of virus-like particles (VLPs). VLPs mimic the viral particle without causing an immunodeficiency disease. HIV-like particles (HIV-LP) are defined as self-assembling, non-replicating, nonpathogenic, genomeless particles that are similar in size and conformation to intact virions. A variety of VLPs for both HIV and SIV are currently in pre-clinical and clinical trials. This review focuses on the current knowledge regarding the immunogenicity and safety of particle-based vaccine strategies for HIV-1.

  20. HIV-1 protease-induced apoptosis

    Czech Academy of Sciences Publication Activity Database

    Rumlová, Michaela; Křížová, Ivana; Keprová, Alena; Hadravová, Romana; Doležal, Michal; Strohalmová, Karolína; Pichová, Iva; Hájek, Miroslav; Ruml, T.

    2014-01-01

    Roč. 11, May 20 (2014), 37/1-37/15 ISSN 1742-4690 R&D Projects: GA ČR GA204/09/1388 Institutional support: RVO:61388963 Keywords : HIV protease * BCA3 * AKIP-1 * apoptosis * mitochondria Subject RIV: EE - Microbiology, Virology Impact factor: 4.185, year: 2014 http://www.retrovirology.com/content/11/1/37