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Sample records for hiv-1 fusion define

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

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    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.

  2. Multimerized CHR-derived peptides as HIV-1 fusion inhibitors.

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    Nomura, Wataru; Hashimoto, Chie; Suzuki, Takaharu; Ohashi, Nami; Fujino, Masayuki; Murakami, Tsutomu; Yamamoto, Naoki; Tamamura, Hirokazu

    2013-08-01

    To date, several HIV-1 fusion inhibitors based on the carboxy-terminal leucine/isoleucine heptad repeat (CHR) region of an HIV-1 envelope protein gp41 have been discovered. We have shown that a synthetic peptide mimetic of a trimer form of the CHR-derived peptide C34 has potent inhibitory activity against the HIV-1 fusion mechanism, compared to a monomer C34 peptide. The present study revealed that a dimeric form of C34 is evidently structurally critical for fusion inhibitors, and that the activity of multimerized CHR-derived peptides in fusion inhibition is affected by the properties of the unit peptides C34, SC34EK, and T20. The fluorescence-based study suggested that the N36-interactive sites of the C34 trimer, including hydrophobic residues, are exposed outside the trimer and that trimerization of C34 caused a remarkable increase in fusion inhibitory activity. The present results could be useful in the design of fusion inhibitors against viral infections which proceed via membrane fusion with host cells. Copyright © 2013 The Authors. Published by Elsevier Ltd.. All rights reserved.

  3. Inhibition of HIV-1 endocytosis allows lipid mixing at the plasma membrane, but not complete fusion

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    de la Vega Michelle

    2011-12-01

    Full Text Available Abstract Background We recently provided evidence that HIV-1 enters HeLa-derived TZM-bl and lymphoid CEMss cells by fusing with endosomes, whereas its fusion with the plasma membrane does not proceed beyond the lipid mixing step. The mechanism of restriction of HIV-1 fusion at the cell surface and/or the factors that aid the virus entry from endosomes remain unclear. Results We examined HIV-1 fusion with a panel of target cells lines and with primary CD4+ T cells. Kinetic measurements of fusion combined with time-resolved imaging of single viruses further reinforced the notion that HIV-1 enters the cells via endocytosis and fusion with endosomes. Furthermore, we attempted to deliberately redirect virus fusion to the plasma membrane, using two experimental strategies. First, the fusion reaction was synchronized by pre-incubating the viruses with cells at reduced temperature to allow CD4 and coreceptors engagement, but not the virus uptake or fusion. Subsequent shift to a physiological temperature triggered accelerated virus uptake followed by entry from endosomes, but did not permit fusion at the cell surface. Second, blocking HIV-1 endocytosis by a small-molecule dynamin inhibitor, dynasore, resulted in transfer of viral lipids to the plasma membrane without any detectable release of the viral content into the cytosol. We also found that a higher concentration of dynasore is required to block the HIV-endosome fusion compared to virus internalization. Conclusions Our results further support the notion that HIV-1 enters disparate cell types through fusion with endosomes. The block of HIV-1 fusion with the plasma membrane at a post-lipid mixing stage shows that this membrane is not conducive to fusion pore formation and/or enlargement. The ability of dynasore to interfere with the virus-endosome fusion suggests that dynamin could be involved in two distinct steps of HIV-1 entry - endocytosis and fusion within intracellular compartments.

  4. Measuring replication competent HIV-1: advances and challenges in defining the latent reservoir.

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    Wang, Zheng; Simonetti, Francesco R; Siliciano, Robert F; Laird, Gregory M

    2018-02-13

    Antiretroviral therapy cannot cure HIV-1 infection due to the persistence of a small number of latently infected cells harboring replication-competent proviruses. Measuring persistent HIV-1 is challenging, as it consists of a mosaic population of defective and intact proviruses that can shift from a state of latency to active HIV-1 transcription. Due to this complexity, most of the current assays detect multiple categories of persistent HIV-1, leading to an overestimate of the true size of the latent reservoir. Here, we review the development of the viral outgrowth assay, the gold-standard quantification of replication-competent proviruses, and discuss the insights provided by full-length HIV-1 genome sequencing methods, which allowed us to unravel the composition of the proviral landscape. In this review, we provide a dissection of what defines HIV-1 persistence and we examine the unmet needs to measure the efficacy of interventions aimed at eliminating the HIV-1 reservoir.

  5. P2X1 Receptor Antagonists Inhibit HIV-1 Fusion by Blocking Virus-Coreceptor Interactions.

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    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

  6. Biochemistry and biophysics of HIV-1 gp41 - membrane interactions and implications for HIV-1 envelope protein mediated viral-cell fusion and fusion inhibitor design.

    Science.gov (United States)

    Cai, Lifeng; Gochin, Miriam; Liu, Keliang

    2011-12-01

    Human immunodeficiency virus type 1 (HIV-1), the pathogen of acquired immunodeficiency syndrome (AIDS), causes ~2 millions death every year and still defies an effective vaccine. HIV-1 infects host cells through envelope protein - mediated virus-cell fusion. The transmembrane subunit of envelope protein, gp41, is the molecular machinery which facilitates fusion. Its ectodomain contains several distinguishing functional domains, fusion peptide (FP), Nterminal heptad repeat (NHR), C-terminal heptad repeat (CHR) and membrane proximal extracellular region (MPER). During the fusion process, FP inserts into the host cell membrane, and an extended gp41 prehairpin conformation bridges the viral and cell membranes through MPER and FP respectively. Subsequent conformational change of the unstable prehairpin results in a coiled-coil 6-helix bundle (6HB) structure formed between NHR and CHR. The energetics of 6HB formation drives membrane apposition and fusion. Drugs targeting gp41 functional domains to prevent 6HB formation inhibit HIV-1 infection. T20 (enfuvirtide, Fuzeon) was approved by the US FDA in 2003 as the first fusion inhibitor. It is a 36-residue peptide from the gp41 CHR, and it inhibits 6HB formation by targeting NHR and lipids. Development of new fusion inhibitors, especially small molecule drugs, is encouraged to overcome the shortcomings of T20 as a peptide drug. Hydrophobic characteristics and membrane association are critical for gp41 function and mechanism of action. Research in gp41-membrane interactions, using peptides corresponding to specific functional domains, or constructs including several interactive domains, are reviewed here to get a better understanding of gp41 mediated virus-cell fusion that can inform or guide the design of new HIV-1 fusion inhibitors.

  7. Defining the Interaction of HIV-1 with the Mucosal Barriers of the Female Reproductive Tract

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    Carias, Ann M.; McCoombe, Scott; McRaven, Michael; Anderson, Meegan; Galloway, Nicole; Vandergrift, Nathan; Fought, Angela J.; Lurain, John; Duplantis, Maurice; Veazey, Ronald S.

    2013-01-01

    Worldwide, HIV-1 infects millions of people annually, the majority of whom are women. To establish infection in the female reproductive tract (FRT), HIV-1 in male ejaculate must overcome numerous innate and adaptive immune factors, traverse the genital epithelium, and establish infection in underlying CD4+ target cells. How the virus achieves this remains poorly defined. By utilizing a new technique, we define how HIV-1 interacts with different tissues of the FRT using human cervical explants and in vivo exposure in the rhesus macaque vaginal transmission model. Despite previous claims of the squamous epithelium being an efficient barrier to virus entry, we reveal that HIV-1 can penetrate both intact columnar and squamous epithelial barriers to depths where the virus can encounter potential target cells. In the squamous epithelium, we identify virus entry occurring through diffusive percolation, penetrating areas where cell junctions are absent. In the columnar epithelium, we illustrate that virus does not transverse barriers as well as previously thought due to mucus impediment. We also show a statistically significant correlation between the viral load of inocula and the ability of HIV-1 to pervade the squamous barrier. Overall, our results suggest a diffusive percolation mechanism for the initial events of HIV-1 entry. With these data, we also mathematically extrapolate the number of HIV-1 particles that penetrate the mucosa per coital act, providing a biological description of the mechanism for HIV-1 transmission during the acute and chronic stages of infection. PMID:23966398

  8. 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

  9. A sensitive HIV-1 envelope induced fusion assay identifies fusion enhancement of thrombin

    International Nuclear Information System (INIS)

    Cheng, De-Chun; Zhong, Guo-Cai; Su, Ju-Xiang; Liu, Yan-Hong; Li, Yan; Wang, Jia-Ye; Hattori, Toshio; Ling, Hong; Zhang, Feng-Min

    2010-01-01

    To evaluate the interaction between HIV-1 envelope glycoprotein (Env) and target cell receptors, various cell-cell-fusion assays have been developed. In the present study, we established a novel fusion system. In this system, the expression of the sensitive reporter gene, firefly luciferase (FL) gene, in the target cells was used to evaluate cell fusion event. Simultaneously, constitutively expressed Renilla luciferase (RL) gene was used to monitor effector cell number and viability. FL gave a wider dynamic range than other known reporters and the introduction of RL made the assay accurate and reproducible. This system is especially beneficial for investigation of potential entry-influencing agents, for its power of ruling out the false inhibition or enhancement caused by the artificial cell-number variation. As a case study, we applied this fusion system to observe the effect of a serine protease, thrombin, on HIV Env-mediated cell-cell fusion and have found the fusion enhancement activity of thrombin over two R5-tropic HIV strains.

  10. Identification of a human protein-derived HIV-1 fusion inhibitor targeting the gp41 fusion core structure.

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    Lijun Chao

    Full Text Available The HIV-1 envelope glycoprotein (Env gp41 plays a crucial role in the viral fusion process. The peptides derived from the C-terminal heptad repeat (CHR of gp41 are potent HIV fusion inhibitors. However, the activity of these anti-HIV-1 peptides in vivo may be attenuated by their induction of anti-gp41 antibodies. Thus, it is essential to identify antiviral peptides or proteins with low, or no, immunogenicity to humans. Here, we found that the C-terminal fragment (aa 462-521 of the human POB1 (the partner of RalBP1, designated C60, is an HIV-1 fusion inhibitor. It bound to N36, the peptide derived from the N-terminal heptad repeat (NHR of gp41, and to the six-helix bundle (6-HB formed by N36 and C34, a CHR-peptide, but it did not bind to C34. Unlike the CHR-peptides, C60 did not block gp41 6-HB formation. Rather, results suggest that C60 inhibits HIV-1 fusion by binding to the 6-HB, in particular, the residues in the gp41 NHR domain that are exposed on the surface of 6-HB. Since 6-HB plays a crucial role in the late stage of fusion between the viral envelope and endosomal membrane during the endocytic process of HIV-1, C60 may serve as a host restriction factor to suppress HIV-1 entry into CD4+ T lymphocytes. Taken together, it can be concluded from these results that C60 can be used as a lead for the development of anti-HIV-1 therapeutics or microbicides for the treatment and prevention of HIV-1 infection, as well as a molecular probe to study the fusogenic mechanism of HIV-1.

  11. Rational design of highly potent HIV-1 fusion inhibitory proteins: Implication for developing antiviral therapeutics

    International Nuclear Information System (INIS)

    Ni Ling; Gao, George F.; Tien Po

    2005-01-01

    Recombinant protein containing one heptad-repeat 1 (HR1) segment and one HR2 segment of the HIV-1 gp41 (HR1-HR2) has been shown to fold into thermally stable six-helix bundle, representing the fusogenic core of gp41. In this study, we have used the fusogenic core as a scaffold to design HIV-1 fusion inhibitory proteins by linking another HR1 to the C terminus of HR1-HR2 (HR121) or additional HR2 to the N terminus of HR1-HR2 (HR212). Both recombinant proteins could be abundantly and solubly expressed and easily purified, exhibiting high stability and potent inhibitory activity on HIV-1 fusion with IC 50 values of 16.2 ± 2.8 and 2.8 ± 0.63 nM, respectively. These suggest that these rationally designed proteins can be further developed as novel anti-HIV-1 therapeutics

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

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    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.

  13. Early and late HIV-1 membrane fusion events are impaired by sphinganine lipidated peptides that target the fusion site.

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    Klug, Yoel A; Ashkenazi, Avraham; Viard, Mathias; Porat, Ziv; Blumenthal, Robert; Shai, Yechiel

    2014-07-15

    Lipid-conjugated peptides have advanced the understanding of membrane protein functions and the roles of lipids in the membrane milieu. These lipopeptides modulate various biological systems such as viral fusion. A single function has been suggested for the lipid, binding to the membrane and thus elevating the local concentration of the peptide at the target site. In the present paper, we challenged this argument by exploring in-depth the antiviral mechanism of lipopeptides, which comprise sphinganine, the lipid backbone of DHSM (dihydrosphingomyelin), and an HIV-1 envelope-derived peptide. Surprisingly, we discovered a partnership between the lipid and the peptide that impaired early membrane fusion events by reducing CD4 receptor lateral diffusion and HIV-1 fusion peptide-mediated lipid mixing. Moreover, only the joint function of sphinganine and its conjugate peptide disrupted HIV-1 fusion protein assembly and folding at the later fusion steps. Via imaging techniques we revealed for the first time the direct localization of these lipopeptides to the virus-cell and cell-cell contact sites. Overall, the findings of the present study may suggest lipid-protein interactions in various biological systems and may help uncover a role for elevated DHSM in HIV-1 and its target cell membranes.

  14. Optimizing HIV-1 protease production in Escherichia coli as fusion protein

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    Piubelli Luciano

    2011-06-01

    Full Text Available Abstract Background Human immunodeficiency virus (HIV is the etiological agent in AIDS and related diseases. The aspartyl protease encoded by the 5' portion of the pol gene is responsible for proteolytic processing of the gag-pol polyprotein precursor to yield the mature capsid protein and the reverse transcriptase and integrase enzymes. The HIV protease (HIV-1Pr is considered an attractive target for designing inhibitors which could be used to tackle AIDS and therefore it is still the object of a number of investigations. Results A recombinant human immunodeficiency virus type 1 protease (HIV-1Pr was overexpressed in Escherichia coli cells as a fusion protein with bacterial periplasmic protein dithiol oxidase (DsbA or glutathione S-transferase (GST, also containing a six-histidine tag sequence. Protein expression was optimized by designing a suitable HIV-1Pr cDNA (for E. coli expression and to avoid autoproteolysis and by screening six different E. coli strains and five growth media. The best expression yields were achieved in E. coli BL21-Codon Plus(DE3-RIL host and in TB or M9 medium to which 1% (w/v glucose was added to minimize basal expression. Among the different parameters assayed, the presence of a buffer system (based on phosphate salts and a growth temperature of 37°C after adding IPTG played the main role in enhancing protease expression (up to 10 mg of chimeric DsbA:HIV-1Pr/L fermentation broth. GST:HIVPr was in part (50% produced as soluble protein while the overexpressed DsbA:HIV-1Pr chimeric protein largely accumulated in inclusion bodies as unprocessed fusion protein. A simple refolding procedure was developed on HiTrap Chelating column that yielded a refolded DsbA:HIV-1Pr with a > 80% recovery. Finally, enterokinase digestion of resolubilized DsbA:HIV-1Pr gave more than 2 mg of HIV-1Pr per liter of fermentation broth with a purity ≤ 80%, while PreScission protease cleavage of soluble GST:HIVPr yielded ~ 0.15 mg of pure HIV-1

  15. Measuring replication competent HIV-1: advances and challenges in defining the latent reservoir

    OpenAIRE

    Wang, Zheng; Simonetti, Francesco R.; Siliciano, Robert F.; Laird, Gregory M.

    2018-01-01

    Antiretroviral therapy cannot cure HIV-1 infection due to the persistence of a small number of latently infected cells harboring replication-competent proviruses. Measuring persistent HIV-1 is challenging, as it consists of a mosaic population of defective and intact proviruses that can shift from a state of latency to active HIV-1 transcription. Due to this complexity, most of the current assays detect multiple categories of persistent HIV-1, leading to an overestimate of the true size of th...

  16. Maturation of the viral core enhances the fusion of HIV-1 particles with primary human T cells and monocyte-derived macrophages

    International Nuclear Information System (INIS)

    Jiang Jiyang; Aiken, Christopher

    2006-01-01

    HIV-1 infection requires fusion of viral and cellular membranes in a reaction catalyzed by the viral envelope proteins gp120 and gp41. We recently reported that efficient HIV-1 particle fusion with target cells is linked to maturation of the viral core by an activity of the gp41 cytoplasmic domain. Here, we show that maturation enhances the fusion of a variety of recombinant viruses bearing primary and laboratory-adapted Env proteins with primary human CD4 + T cells. Overall, HIV-1 fusion was more dependent on maturation for viruses bearing X4-tropic envelope proteins than for R5-tropic viruses. Fusion of HIV-1 with monocyte-derived macrophages was also dependent on particle maturation. We conclude that the ability to couple fusion to particle maturation is a common feature of HIV-1 Env proteins and may play an important role during HIV-1 replication in vivo

  17. Fluorescent protein-tagged Vpr dissociates from HIV-1 core after viral fusion and rapidly enters the cell nucleus.

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    Desai, Tanay M; Marin, Mariana; Sood, Chetan; Shi, Jiong; Nawaz, Fatima; Aiken, Christopher; Melikyan, Gregory B

    2015-10-29

    HIV-1 Vpr is recruited into virions during assembly and appears to remain associated with the viral core after the reverse transcription and uncoating steps of entry. This feature has prompted the use of fluorescently labeled Vpr to visualize viral particles and to follow trafficking of post-fusion HIV-1 cores in the cytoplasm. Here, we tracked single pseudovirus entry and fusion and observed that fluorescently tagged Vpr gradually dissociates from post-fusion viral cores over the course of several minutes and accumulates in the nucleus. Kinetics measurements showed that fluorescent Vpr released from the cores very rapidly entered the cell nucleus. More than 10,000 Vpr molecules can be delivered into the cell nucleus within 45 min of infection by HIV-1 particles pseudotyped with the avian sarcoma and leukosis virus envelope glycoprotein. The fraction of Vpr from cell-bound viruses that accumulated in the nucleus was proportional to the extent of virus-cell fusion and was fully blocked by viral fusion inhibitors. Entry of virus-derived Vpr into the nucleus occurred independently of envelope glycoproteins or target cells. Fluorescence correlation spectroscopy revealed two forms of nuclear Vpr-monomers and very large complexes, likely involving host factors. The kinetics of viral Vpr entering the nucleus after fusion was not affected by point mutations in the capsid protein that alter the stability of the viral core. The independence of Vpr shedding of capsid stability and its relatively rapid dissociation from post-fusion cores suggest that this process may precede capsid uncoating, which appears to occur on a slower time scale. Our results thus demonstrate that a bulk of fluorescently labeled Vpr incorporated into HIV-1 particles is released shortly after fusion. Future studies will address the question whether the quick and efficient nuclear delivery of Vpr derived from incoming viruses can regulate subsequent steps of HIV-1 infection.

  18. Discovery of small-molecule HIV-1 fusion and integrase inhibitors oleuropein and hydroxytyrosol: Part I. Integrase inhibition

    International Nuclear Information System (INIS)

    Lee-Huang, Sylvia; Huang, Philip Lin; Zhang Dawei; Lee, Jae Wook; Bao Ju; Sun Yongtao; Chang, Young-Tae; Zhang, John; Huang, Paul Lee

    2007-01-01

    We have identified oleuropein (Ole) and hydroxytyrosol (HT) as a unique class of HIV-1 inhibitors from olive leaf extracts effective against viral fusion and integration. We used molecular docking simulation to study the interactions of Ole and HT with viral targets. We find that Ole and HT bind to the conserved hydrophobic pocket on the surface of the HIV-gp41 fusion domain by hydrogen bonds with Q577 and hydrophobic interactions with I573, G572, and L568 on the gp41 N-terminal heptad repeat peptide N36, interfering with formation of the gp41 fusion-active core. To test and confirm modeling predications, we examined the effect of Ole and HT on HIV-1 fusion complex formation using native polyacrylamide gel electrophoresis and circular dichroism spectroscopy. Ole and HT exhibit dose-dependent inhibition on HIV-1 fusion core formation with EC 50 s of 66-58 nM, with no detectable toxicity. Our findings on effects of HIV-1 integrase are reported in the subsequent article

  19. Role of protein disulfide isomerase and other thiol-reactive proteins in HIV-1 envelope protein-mediated fusion

    International Nuclear Information System (INIS)

    Ou Wu; Silver, Jonathan

    2006-01-01

    Cell-surface protein disulfide isomerase (PDI) has been proposed to promote disulfide bond rearrangements in HIV-1 envelope protein (Env) that accompany Env-mediated fusion. We evaluated the role of PDI in ways that have not been previously tested by downregulating PDI with siRNA and by overexpressing wild-type or variant forms of PDI in transiently and stably transfected cells. These manipulations, as well as treatment with anti-PDI antibodies, had only small effects on infection or cell fusion mediated by NL4-3 or AD8 strains of HIV-1. However, the cell-surface thiol-reactive reagent 5, 5'-dithiobis(2-nitrobenzoic acid) (DTNB) had a much stronger inhibitory effect in our system, suggesting that cell-surface thiol-containing molecules other than PDI, acting alone or in concert, have a greater effect than PDI on HIV-1 Env-mediated fusion. We evaluated one such candidate, thioredoxin, a PDI family member reported to reduce a labile disulfide bond in CD4. We found that the ability of thioredoxin to reduce the disulfide bond in CD4 is enhanced in the presence of HIV-1 Env gp120 and that thioredoxin also reduces disulfide bonds in gp120 directly in the absence of CD4. We discuss the implications of these observations for identification of molecules involved in disulfide rearrangements in Env during fusion

  20. Cloning, Expression and Purification of the Recombinant HIV-1 Tat-Nef Fusion Protein in Prokaryotic Expression System

    OpenAIRE

    Somayeh Kadkhodayan; Shiva Irani; Seyed Mehdi Sadat; Fatemeh Fotouhi; Azam Bolhassani

    2016-01-01

    Abstract Background: Nef is one of the HIV-1 critical proteins, because it is essential for viral replication and AIDS disease progression and induction of immune response against it can partially inhibit viral infection. Moreover, a domain of the HIV-1 Trans-Activator of Transcription (Tat, 48-60 aa) could act as a cell penetrating peptide (CPP). In current study, cloning and expression of Tat-Nef fusion protein was performed in E. coli for the first time. The protein expression was confi...

  1. Exploring the membrane fusion mechanism through force-induced disassembly of HIV-1 six-helix bundle

    Energy Technology Data Exchange (ETDEWEB)

    Gao, Kai [Key Laboratory of RNA Biology, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101 (China); Beijing Key Laboratory of Noncoding RNA, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101 (China); University of Chinese Academy of Sciences, Beijing 100049 (China); Zhang, Yong [Key Laboratory of RNA Biology, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101 (China); Beijing Key Laboratory of Noncoding RNA, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101 (China); Lou, Jizhong, E-mail: jlou@ibp.ac.cn [Key Laboratory of RNA Biology, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101 (China); Beijing Key Laboratory of Noncoding RNA, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101 (China)

    2016-05-13

    Enveloped virus, such as HIV-1, employs membrane fusion mechanism to invade into host cell. HIV-1 gp41 ectodomain uses six-helix bundle configuration to accomplish this process. Using molecular dynamic simulations, we confirmed the stability of this six-helix bundle by showing high occupancy of hydrogen bonds and hydrophobic interactions. Key residues and interactions important for the bundle integration were characterized by force-induced unfolding simulations of six-helix bundle, exhibiting the collapse order of these groups of interactions. Moreover, our results in some way concerted with a previous theory that the formation of coiled-coil choose a route which involved cooperative interactions between the N-terminal and C-terminal helix. -- Highlights: •Unfolding of HIV-1 gp41 six-helix bundle is studied by molecular dynamics simulations. •Specific interactions responsible for the stability of HIV-1 envelope post-fusion conformation were identified. •The gp41 six-helix bundle transition inducing membrane fusion might be a cooperative process of the three subunits.

  2. Monocyte-lymphocyte fusion induced by the HIV-1 envelope generates functional heterokaryons with an activated monocyte-like phenotype

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    Martínez-Méndez, David; Rivera-Toledo, Evelyn; Ortega, Enrique; Licona-Limón, Ileana; Huerta, Leonor, E-mail: leonorhh@biomedicas.unam.mx

    2017-03-01

    Enveloped viruses induce cell-cell fusion when infected cells expressing viral envelope proteins interact with target cells, or through the contact of cell-free viral particles with adjoining target cells. CD4{sup +} T lymphocytes and cells from the monocyte-macrophage lineage express receptors for HIV envelope protein. We have previously reported that lymphoid Jurkat T cells expressing the HIV-1 envelope protein (Env) can fuse with THP-1 monocytic cells, forming heterokaryons with a predominantly myeloid phenotype. This study shows that the expression of monocytic markers in heterokaryons is stable, whereas the expression of lymphoid markers is mostly lost. Like THP-1 cells, heterokaryons exhibited FcγR-dependent phagocytic activity and showed an enhanced expression of the activation marker ICAM-1 upon stimulation with PMA. In addition, heterokaryons showed morphological changes compatible with maturation, and high expression of the differentiation marker CD11b in the absence of differentiation-inducing agents. No morphological change nor increase in CD11b expression were observed when an HIV-fusion inhibitor blocked fusion, or when THP-1 cells were cocultured with Jurkat cells expressing a non-fusogenic Env protein, showing that differentiation was not induced merely by cell-cell interaction but required cell-cell fusion. Inhibition of TLR2/TLR4 signaling by a TIRAP inhibitor greatly reduced the expression of CD11b in heterokaryons. Thus, lymphocyte-monocyte heterokaryons induced by HIV-1 Env are stable and functional, and fusion prompts a phenotype characteristic of activated monocytes via intracellular TLR2/TLR4 signaling. - Highlights: • Jurkat T cells expressing the HIV-1 envelope fuse with THP-1 monocytes. • Heterokaryons display a dominant myeloid phenotype and monocyte function. • Heterokaryons exhibit activation features in the absence of activation agents. • Activation is not due to cell-cell interaction but requires cell-cell fusion. • The

  3. Monocyte-lymphocyte fusion induced by the HIV-1 envelope generates functional heterokaryons with an activated monocyte-like phenotype

    International Nuclear Information System (INIS)

    Martínez-Méndez, David; Rivera-Toledo, Evelyn; Ortega, Enrique; Licona-Limón, Ileana; Huerta, Leonor

    2017-01-01

    Enveloped viruses induce cell-cell fusion when infected cells expressing viral envelope proteins interact with target cells, or through the contact of cell-free viral particles with adjoining target cells. CD4"+ T lymphocytes and cells from the monocyte-macrophage lineage express receptors for HIV envelope protein. We have previously reported that lymphoid Jurkat T cells expressing the HIV-1 envelope protein (Env) can fuse with THP-1 monocytic cells, forming heterokaryons with a predominantly myeloid phenotype. This study shows that the expression of monocytic markers in heterokaryons is stable, whereas the expression of lymphoid markers is mostly lost. Like THP-1 cells, heterokaryons exhibited FcγR-dependent phagocytic activity and showed an enhanced expression of the activation marker ICAM-1 upon stimulation with PMA. In addition, heterokaryons showed morphological changes compatible with maturation, and high expression of the differentiation marker CD11b in the absence of differentiation-inducing agents. No morphological change nor increase in CD11b expression were observed when an HIV-fusion inhibitor blocked fusion, or when THP-1 cells were cocultured with Jurkat cells expressing a non-fusogenic Env protein, showing that differentiation was not induced merely by cell-cell interaction but required cell-cell fusion. Inhibition of TLR2/TLR4 signaling by a TIRAP inhibitor greatly reduced the expression of CD11b in heterokaryons. Thus, lymphocyte-monocyte heterokaryons induced by HIV-1 Env are stable and functional, and fusion prompts a phenotype characteristic of activated monocytes via intracellular TLR2/TLR4 signaling. - Highlights: • Jurkat T cells expressing the HIV-1 envelope fuse with THP-1 monocytes. • Heterokaryons display a dominant myeloid phenotype and monocyte function. • Heterokaryons exhibit activation features in the absence of activation agents. • Activation is not due to cell-cell interaction but requires cell-cell fusion. • The

  4. Role of transmitted Gag CTL polymorphisms in defining replicative capacity and early HIV-1 pathogenesis.

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    Jessica L Prince

    Full Text Available Initial studies of 88 transmission pairs in the Zambia Emory HIV Research Project cohort demonstrated that the number of transmitted HLA-B associated polymorphisms in Gag, but not Nef, was negatively correlated to set point viral load (VL in the newly infected partners. These results suggested that accumulation of CTL escape mutations in Gag might attenuate viral replication and provide a clinical benefit during early stages of infection. Using a novel approach, we have cloned gag sequences isolated from the earliest seroconversion plasma sample from the acutely infected recipient of 149 epidemiologically linked Zambian transmission pairs into a primary isolate, subtype C proviral vector, MJ4. We determined the replicative capacity (RC of these Gag-MJ4 chimeras by infecting the GXR25 cell line and quantifying virion production in supernatants via a radiolabeled reverse transcriptase assay. We observed a statistically significant positive correlation between RC conferred by the transmitted Gag sequence and set point VL in newly infected individuals (p = 0.02. Furthermore, the RC of Gag-MJ4 chimeras also correlated with the VL of chronically infected donors near the estimated date of infection (p = 0.01, demonstrating that virus replication contributes to VL in both acute and chronic infection. These studies also allowed for the elucidation of novel sites in Gag associated with changes in RC, where rare mutations had the greatest effect on fitness. Although we observed both advantageous and deleterious rare mutations, the latter could point to vulnerable targets in the HIV-1 genome. Importantly, RC correlated significantly (p = 0.029 with the rate of CD4+ T cell decline over the first 3 years of infection in a manner that is partially independent of VL, suggesting that the replication capacity of HIV-1 during the earliest stages of infection is a determinant of pathogenesis beyond what might be expected based on set point VL alone.

  5. Structure-Related Roles for the Conservation of the HIV-1 Fusion Peptide Sequence Revealed by Nuclear Magnetic Resonance.

    Science.gov (United States)

    Serrano, Soraya; Huarte, Nerea; Rujas, Edurne; Andreu, David; Nieva, José L; Jiménez, María Angeles

    2017-10-17

    Despite extensive characterization of the human immunodeficiency virus type 1 (HIV-1) hydrophobic fusion peptide (FP), the structure-function relationships underlying its extraordinary degree of conservation remain poorly understood. Specifically, the fact that the tandem repeat of the FLGFLG tripeptide is absolutely conserved suggests that high hydrophobicity may not suffice to unleash FP function. Here, we have compared the nuclear magnetic resonance (NMR) structures adopted in nonpolar media by two FP surrogates, wtFP-tag and scrFP-tag, which had equal hydrophobicity but contained wild-type and scrambled core sequences LFLGFLG and FGLLGFL, respectively. In addition, these peptides were tagged at their C-termini with an epitope sequence that folded independently, thereby allowing Western blot detection without interfering with FP structure. We observed similar α-helical FP conformations for both specimens dissolved in the low-polarity medium 25% (v/v) 1,1,1,3,3,3-hexafluoro-2-propanol (HFIP), but important differences in contact with micelles of the membrane mimetic dodecylphosphocholine (DPC). Thus, whereas wtFP-tag preserved a helix displaying a Gly-rich ridge, the scrambled sequence lost in great part the helical structure upon being solubilized in DPC. Western blot analyses further revealed the capacity of wtFP-tag to assemble trimers in membranes, whereas membrane oligomers were not observed in the case of the scrFP-tag sequence. We conclude that, beyond hydrophobicity, preserving sequence order is an important feature for defining the secondary structures and oligomeric states adopted by the HIV FP in membranes.

  6. Cloning, Expression and Purification of the Recombinant HIV-1 Tat-Nef Fusion Protein in Prokaryotic Expression System

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    Somayeh Kadkhodayan

    2016-07-01

    Full Text Available Abstract Background: Nef is one of the HIV-1 critical proteins, because it is essential for viral replication and AIDS disease progression and induction of immune response against it can partially inhibit viral infection. Moreover, a domain of the HIV-1 Trans-Activator of Transcription (Tat, 48-60 aa could act as a cell penetrating peptide (CPP. In current study, cloning and expression of Tat-Nef fusion protein was performed in E. coli for the first time. The protein expression was confirmed by western blot analysis and was purified using reverse staining method. Materials and Methods: In this experimental study, primarily, cloning of Tat-Nef fusion gene was done in pGEX6p2 expression vector. Then, the expression of Tat-Nef recombinat protein in E.coli BL21 (DE3 strain was performed by using IPTG inducer. The protein expression was confirmed by SDS-PAGE and western blotting using anti-Nef monoclonal antibody. Then, the recombinant fusion protein was purified from gel using reverse staining method. Results: The results of PCR analysis and enzyme digestion showed a clear band of ~ 726 bp in agarose gel indicating the correct Tat-Nef fusion cloning in pGEX6p2 prokaryotic expression vector. In addition, a 54 kDa band of Tat-Nef on SDS-PAGE revealed Tat-Nef protein expression that western blot analysis using anti-Nef monoclonal antibody confirmed it. Conclusion: The purified Tat-Nef recombinant fusion protein will be used as an antigen for protein vaccine design against HIV infection.

  7. The Effects of the Recombinant CCR5 T4 Lysozyme Fusion Protein on HIV-1 Infection.

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    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.

  8. Impact of gender on the risk of AIDS-defining illnesses and mortality in Danish HIV-1-infected patients

    DEFF Research Database (Denmark)

    Thorsteinsson, Kristina; Ladelund, Steen; Jensen-Fangel, Søren

    2012-01-01

    Abstract Background: Gender differences in the risk of AIDS-defining illness (ADI) and mortality have been reported in the HIV-1-infected (HIV-positive) population, with conflicting findings. We aimed to assess the impact of gender on the risk of ADI and death in HIV-positive patients infected...... sexually. Methods: This was a population-based, nationwide cohort study of incident Danish HIV-positive individuals infected by sexual contact. Outcomes were progression to AIDS and death. We used Cox proportional hazards models and Poisson regression analyses to calculate the risk of progression to AIDS...... diagnosis MSM had a lower prevalence of AIDS compared to MSW. Women and MSW presented more often with tuberculosis and less often with AIDS-defining cancers compared to MSM. In the adjusted analyses we observed no differences in progression to AIDS. In the adjusted analyses of risk of death, there were...

  9. cGAS-Mediated Innate Immunity Spreads Intercellularly through HIV-1 Env-Induced Membrane Fusion Sites.

    Science.gov (United States)

    Xu, Shuting; Ducroux, Aurélie; Ponnurangam, Aparna; Vieyres, Gabrielle; Franz, Sergej; Müsken, Mathias; Zillinger, Thomas; Malassa, Angelina; Ewald, Ellen; Hornung, Veit; Barchet, Winfried; Häussler, Susanne; Pietschmann, Thomas; Goffinet, Christine

    2016-10-12

    Upon sensing cytoplasmic retroviral DNA in infected cells, cyclic GMP-AMP (cGAMP) synthase (cGAS) produces the cyclic dinucleotide cGAMP, which activates STING to trigger a type I interferon (IFN) response. We find that membrane fusion-inducing contact between donor cells expressing the HIV envelope (Env) and primary macrophages endogenously expressing the HIV receptor CD4 and coreceptor enable intercellular transfer of cGAMP. This cGAMP exchange results in STING-dependent antiviral IFN responses in target macrophages and protection from HIV infection. Furthermore, under conditions allowing cell-to-cell transmission of HIV-1, infected primary T cells, but not cell-free virions, deliver cGAMP to autologous macrophages through HIV-1 Env and CD4/coreceptor-mediated membrane fusion sites and induce a STING-dependent, but cGAS-independent, IFN response in target cells. Collectively, these findings identify an infection-specific mode of horizontal transfer of cGAMP between primary immune cells that may boost antiviral responses, particularly in infected tissues in which cell-to-cell transmission of virions exceeds cell-free infection. Copyright © 2016 Elsevier Inc. All rights reserved.

  10. Structural Insights into the Mechanisms of Action of Short-Peptide HIV-1 Fusion Inhibitors Targeting the Gp41 Pocket

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    Xiujuan Zhang

    2018-02-01

    Full Text Available The deep hydrophobic pocket of HIV-1 gp41 has been considered a drug target, but short-peptides targeting this site usually lack potent antiviral activity. By applying the M-T hook structure, we previously generated highly potent short-peptide fusion inhibitors that specifically targeted the pocket site, such as MT-SC22EK, HP23L, and LP-11. Here, the crystal structures of HP23L and LP-11 bound to the target mimic peptide N36 demonstrated the critical intrahelical and interhelical interactions, especially verifying that the hook-like conformation was finely adopted while the methionine residue was replaced by the oxidation-less prone residue leucine, and that addition of an extra glutamic acid significantly enhanced the binding and inhibitory activities. The structure of HP23L bound to N36 with two mutations (E49K and L57R revealed the critical residues and motifs mediating drug resistance and provided new insights into the mechanism of action of inhibitors. Therefore, the present data help our understanding for the structure-activity relationship (SAR of HIV-1 fusion inhibitors and facilitate the development of novel antiviral drugs.

  11. The risk of AIDS-defining events is decreasing over time in the German HIV-1 Seroconverter Cohort

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    Altmann Mathias

    2012-04-01

    Full Text Available Abstract Background With ageing of the HIV-infected population, long-term exposure to treatment, varying adherence, emerging resistance and complications to therapies, effectiveness of Highly Active Antiretroviral Therapy (HAART needs to be monitored continuously at the population level. The German HIV-1 Seroconverter Cohort is a multi-centre, open, long-term observational cohort including patients with a known or reliably estimated date of HIV-infection i.e. last negative and first positive HIV antibody test within a maximum three-year interval or laboratory evidence of seroconversion. Our study aims to investigate survival improvements and changes in AIDS risk over calendar periods in the German HIV-1 Seroconverter Cohort. Methods Retrospective (for the pre-1997 period and prospective (since 1997 data from the German HIV-1 Seroconverter Cohort were used. Time from seroconversion to first AIDS-defining event over calendar periods was analysed by using Cox models adjusting for age at seroconversion, sex, transmission groups and short HIV test interval. Kaplan-Meier methods were used to determine expected survival (remaining AIDS-free by calendar period. Results 2162 seroconverters with 8976 person-years of observation were included in our analysis (up to 31.12.2010. A total of 196 first AIDSdefining events were reported. Two periods i.e. 19972000 and 2007-2010 were statistically associated with a reduction in the risk of AIDS, accounting for an overall reduction of 80%. Compared to1997-2000, hazard ratios were 2.6 (95%CI, 1.6-4.8; p=0.000 in pre-1997 and 0.5 (95%CI, 0.3-0.8; p=0.007 in 20072010. Independent risk factor for AIDS progression was age at seroconversion (HR, 1.3 per 10year-increase; p=0.001. Conclusion HAART effectiveness has improved in the German HIV-1-Seroconverter Cohort. The risk to develop AIDS decreased significantly in 19972000 and in 20072010. However, elderly may require particular monitoring in view of their faster

  12. Overlapping effector interfaces define the multiple functions of the HIV-1 Nef polyproline helix

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    Kuo Lillian S

    2012-05-01

    Full Text Available Abstract Background HIV-1 Nef is a multifunctional protein required for full pathogenicity of the virus. As Nef has no known enzymatic activity, it necessarily functions through protein-protein interaction interfaces. A critical Nef protein interaction interface is centered on its polyproline segment (P69VRPQVPLRP78 which contains the helical SH3 domain binding protein motif, PXXPXR. We hypothesized that any Nef-SH3 domain interactions would be lost upon mutation of the prolines or arginine of PXXPXR. Further, mutation of the non-motif “X” residues, (Q73, V74, and L75 would give altered patterns of inhibition for different Nef/SH3 domain protein interactions. Results We found that mutations of either of the prolines or the arginine of PXXPXR are defective for Nef-Hck binding, Nef/activated PAK2 complex formation and enhancement of virion infectivity (EVI. Mutation of the non-motif “X” residues (Q, V and L gave similar patterns of inhibition for Nef/activated PAK2 complex formation and EVI which were distinct from the pattern for Hck binding. These results implicate an SH3 domain containing protein other than Hck for Nef/activated PAK2 complex formation and EVI. We have also mutated Nef residues at the N-and C-terminal ends of the polyproline segment to explore interactions outside of PXXPXR. We discovered a new locus GFP/F (G67, F68, P69 and F90 that is required for Nef/activated PAK2 complex formation and EVI. MHC Class I (MHCI downregulation was only partially inhibited by mutating the PXXPXR motif residues, but was fully inhibited by mutating the C-terminal P78. Further, we observed that MHCI downregulation strictly requires G67 and F68. Our mutational analysis confirms the recently reported structure of the complex between Nef, AP-1 μ1 and the cytoplasmic tail of MHCI, but does not support involvement of an SH3 domain protein in MHCI downregulation. Conclusion Nef has evolved to be dependent on interactions with multiple SH3 domain

  13. Effects of sequence changes in the HIV-1 gp41 fusion peptide on CCR5 inhibitor resistance

    International Nuclear Information System (INIS)

    Anastassopoulou, Cleo G.; Ketas, Thomas J.; Sanders, Rogier W.; Johan Klasse, Per; Moore, John P.

    2012-01-01

    A rare pathway of HIV-1 resistance to small molecule CCR5 inhibitors such as Vicriviroc (VCV) involves changes solely in the gp41 fusion peptide (FP). Here, we show that the G516V change is critical to VCV resistance in PBMC and TZM-bl cells, although it must be accompanied by either M518V or F519I to have a substantial impact. Modeling VCV inhibition data from the two cell types indicated that G516V allows both double mutants to use VCV-CCR5 complexes for entry. The model further identified F519I as an independent determinant of preference for the unoccupied, high-VCV affinity form of CCR5. From inhibitor-free reversion cultures, we also identified a substitution in the inner domain of gp120, T244A, which appears to counter the resistance phenotype created by the FP substitutions. Examining the interplay of these changes will enhance our understanding of Env complex interactions that influence both HIV-1 entry and resistance to CCR5 inhibitors.

  14. 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.

  15. The role of blood cell membrane lipids on the mode of action of HIV-1 fusion inhibitor sifuvirtide

    International Nuclear Information System (INIS)

    Matos, Pedro M.; Freitas, Teresa; Castanho, Miguel A.R.B.; Santos, Nuno C.

    2010-01-01

    Research highlights: → Sifuvirtide interacts with erythrocyte and lymphocyte membrane in a concentration dependent manner by decreasing its dipole potential. → Dipole potential variations in lipid vesicles show sifuvirtide's lipid selectivity towards saturated phosphatidylcholines. → This peptide-membrane interaction may direct the drug towards raft-like membrane domains where the receptors used by HIV are located, facilitating its inhibitory action. -- Abstract: Sifuvirtide is a gp41 based peptide that inhibits HIV-1 fusion with the host cells and is currently under clinical trials. Previous studies showed that sifuvirtide partitions preferably to saturated phosphatidylcholine lipid membranes, instead of fluid-phase lipid vesicles. We extended the study to the interaction of the peptide with circulating blood cells, by using the dipole potential sensitive probe di-8-ANEPPS. Sifuvirtide decreased the dipole potential of erythrocyte and lymphocyte membranes in a concentration dependent manner, demonstrating its interaction. Also, the lipid selectivity of the peptide towards more rigid phosphatidylcholines was confirmed based on the dipole potential variations. Overall, the interaction of the peptide with the cell membranes is a contribution of different lipid preferences that presumably directs the peptide towards raft-like domains where the receptors are located, facilitating the reach of the peptide to its molecular target, the gp41 in its pre-fusion conformation.

  16. A recombinant mimetics of the HIV-1 gp41 prehairpin fusion intermediate fused with human IgG Fc fragment elicits neutralizing antibody response in the vaccinated mice

    International Nuclear Information System (INIS)

    Qi, Zhi; Pan, Chungen; Lu, Hong; Shui, Yuan; Li, Lin; Li, Xiaojuan; Xu, Xueqing; Liu, Shuwen; Jiang, Shibo

    2010-01-01

    Research highlights: → One recombinant mimetics of gp41 prehairpin fusion intermediate (PFI) consisting of gp41 N46 sequence, foldon and IgG Fc, designated N46FdFc, was expressed. → N46FdFc-induced antibodies in mice that neutralized HIV-1 infection, inhibited PIE7 binding to PFI, blocked gp41 six-helix bundle formation, and suppressed HIV-1 mediated cell-cell fusion. → These findings provide an important clue for developing recombinant gp41 PFI mimetics-based HIV vaccines. -- Abstract: HIV-1 gp41 prehairpin fusion intermediate (PFI) composed of three N-terminal heptad repeats (NHR) plays a crucial role in viral fusion and entry and represents an attractive target for anti-HIV therapeutics (e.g., enfuvirtide) and vaccines. In present study, we constructed and expressed two recombinant gp41 PFI mimetics, designated N46Fd and N46FdFc. N46Fd consists of N46 (residues 536-581) in gp41 NHR and foldon (Fd), a trimerization motif. N46FdFc is composed of N46Fd fused with human IgG Fc fragment as an immunoenhancer. We immunized mice with N46 peptide, N46Fd and N46FdFc, respectively, and found that only N46FdFc elicited neutralizing antibody response in mice against infection by HIV-1 strains IIIB (clade B, X4), 92US657 (clade B, R5), and 94UG103 (clade A, X4R5). Anti-N46FdFc antibodies inhibited PIE7 binding to PFI, blocked gp41 six-helix bundle formation, and suppressed HIV-1 mediated cell-cell fusion. These findings provide an important clue for developing recombinant gp41 PFI mimetics-based HIV vaccines.

  17. Adding an Artificial Tail—Anchor to a Peptide-Based HIV-1 Fusion Inhibitor for Improvement of Its Potency and Resistance Profile

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    Shan Su

    2017-11-01

    Full Text Available Peptides derived from the C-terminal heptad repeat (CHR of human immunodeficiency virus type 1 (HIV-1 envelope protein transmembrane subunit gp41, such as T20 (enfuvirtide, can bind to the N-terminal heptad repeat (NHR of gp41 and block six-helix bundle (6-HB formation, thus inhibiting HIV-1 fusion with the target cell. However, clinical application of T20 is limited because of its low potency and genetic barrier to resistance. HP23, the shortest CHR peptide, exhibits better anti-HIV-1 activity than T20, but the HIV-1 strains with E49K mutations in gp41 will become resistant to it. Here, we modified HP23 by extending its C-terminal sequence using six amino acid residues (E6 and adding IDL (Ile-Asp-Leu to the C-terminus of E6, which is expected to bind to the shallow pocket in the gp41 NHR N-terminal region. The newly designed peptide, designated HP23-E6-IDL, was about 2- to 16-fold more potent than HP23 against a broad spectrum of HIV-1 strains and more than 12-fold more effective against HIV-1 mutants resistant to HP23. These findings suggest that addition of an anchor–tail to the C-terminus of a CHR peptide will allow binding with the pocket in the gp41 NHR that may increase the peptide’s antiviral efficacy and its genetic barrier to resistance.

  18. Molecular dynamics modeling the synthetic and biological polymers interactions pre-studied via docking: anchors modified polyanions interference with the HIV-1 fusion mediator.

    Science.gov (United States)

    Tsvetkov, Vladimir B; Serbin, Alexander V

    2014-06-01

    In previous works we reported the design, synthesis and in vitro evaluations of synthetic anionic polymers modified by alicyclic pendant groups (hydrophobic anchors), as a novel class of inhibitors of the human immunodeficiency virus type 1 (HIV-1) entry into human cells. Recently, these synthetic polymers interactions with key mediator of HIV-1 entry-fusion, the tri-helix core of the first heptad repeat regions [HR1]3 of viral envelope protein gp41, were pre-studied via docking in terms of newly formulated algorithm for stepwise approximation from fragments of polymeric backbone and side-group models toward real polymeric chains. In the present article the docking results were verified under molecular dynamics (MD) modeling. In contrast with limited capabilities of the docking, the MD allowed of using much more large models of the polymeric ligands, considering flexibility of both ligand and target simultaneously. Among the synthesized polymers the dinorbornen anchors containing alternating copolymers of maleic acid were selected as the most representative ligands (possessing the top anti-HIV activity in vitro in correlation with the highest binding energy in the docking). To verify the probability of binding of the polymers with the [HR1]3 in the sites defined via docking, various starting positions of polymer chains were tried. The MD simulations confirmed the main docking-predicted priority for binding sites, and possibilities for axial and belting modes of the ligands-target interactions. Some newly MD-discovered aspects of the ligand's backbone and anchor units dynamic cooperation in binding the viral target clarify mechanisms of the synthetic polymers anti-HIV activity and drug resistance prevention.

  19. Fusion proteins of HIV-1 envelope glycoprotein gp120 with CD4-induced antibodies showed enhanced binding to CD4 and CD4 binding site antibodies

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Weizao, E-mail: chenw3@mail.nih.gov [Protein Interactions Group, Frederick National Laboratory for Cancer Research, National Cancer Institute, National Institutes of Health, Frederick, MD 21702 (United States); Feng, Yang [Protein Interactions Group, Frederick National Laboratory for Cancer Research, National Cancer Institute, National Institutes of Health, Frederick, MD 21702 (United States); Wang, Yanping [Protein Interactions Group, Frederick National Laboratory for Cancer Research, National Cancer Institute, National Institutes of Health, Frederick, MD 21702 (United States); The Basic Research Program, Science Applications International Corporation-Frederick, Inc., National Cancer Institute, National Institutes of Health, Frederick, MD 21702 (United States); Zhu, Zhongyu; Dimitrov, Dimiter S. [Protein Interactions Group, Frederick National Laboratory for Cancer Research, National Cancer Institute, National Institutes of Health, Frederick, MD 21702 (United States)

    2012-09-07

    Highlights: Black-Right-Pointing-Pointer Some recombinant HIV-1 gp120s do not preserve their conformations on gp140s. Black-Right-Pointing-Pointer We hypothesize that CD4i antibodies could induce conformational changes in gp120. Black-Right-Pointing-Pointer CD4i antibodies enhance binding of CD4 and CD4bs antibodies to gp120. Black-Right-Pointing-Pointer CD4i antibody-gp120 fusion proteins could have potential as vaccine immunogens. -- Abstract: Development of successful AIDS vaccine immunogens continues to be a major challenge. One of the mechanisms by which HIV-1 evades antibody-mediated neutralizing responses is the remarkable conformational flexibility of its envelope glycoprotein (Env) gp120. Some recombinant gp120s do not preserve their conformations on gp140s and functional viral spikes, and exhibit decreased recognition by CD4 and neutralizing antibodies. CD4 binding induces conformational changes in gp120 leading to exposure of the coreceptor-binding site (CoRbs). In this study, we test our hypothesis that CD4-induced (CD4i) antibodies, which target the CoRbs, could also induce conformational changes in gp120 leading to better exposed conserved neutralizing antibody epitopes including the CD4-binding site (CD4bs). We found that a mixture of CD4i antibodies with gp120 only weakly enhanced CD4 binding. However, such interactions in single-chain fusion proteins resulted in gp120 conformations which bound to CD4 and CD4bs antibodies better than the original or mutagenically stabilized gp120s. Moreover, the two molecules in the fusion proteins synergized with each other in neutralizing HIV-1. Therefore, fusion proteins of gp120 with CD4i antibodies could have potential as components of HIV-1 vaccines and inhibitors of HIV-1 entry, and could be used as reagents to explore the conformational flexibility of gp120 and mechanisms of entry and immune evasion.

  20. Preclinical safety and efficacy of an anti–HIV-1 lentiviral vector containing a short hairpin RNA to CCR5 and the C46 fusion inhibitor

    Directory of Open Access Journals (Sweden)

    Orit Wolstein

    2014-01-01

    Full Text Available Gene transfer has therapeutic potential for treating HIV-1 infection by generating cells that are resistant to the virus. We have engineered a novel self-inactivating lentiviral vector, LVsh5/C46, using two viral-entry inhibitors to block early steps of HIV-1 cycle. The LVsh5/C46 vector encodes a short hairpin RNA (shRNA for downregulation of CCR5, in combination with the HIV-1 fusion inhibitor, C46. We demonstrate here the effective delivery of LVsh5/C46 to human T cell lines, peripheral blood mononuclear cells, primary CD4+ T lymphocytes, and CD34+ hematopoietic stem/progenitor cells (HSPC. CCR5-targeted shRNA (sh5 and C46 peptide were stably expressed in the target cells and were able to effectively protect gene-modified cells against infection with CCR5- and CXCR4-tropic strains of HIV-1. LVsh5/C46 treatment was nontoxic as assessed by cell growth and viability, was noninflammatory, and had no adverse effect on HSPC differentiation. LVsh5/C46 could be produced at a scale sufficient for clinical development and resulted in active viral particles with very low mutagenic potential and the absence of replication-competent lentivirus. Based on these in vitro results, plus additional in vivo safety and efficacy data, LVsh5/C46 is now being tested in a phase 1/2 clinical trial for the treatment of HIV-1 disease.

  1. The conserved residue Arg46 in the N-terminal heptad repeat domain of HIV-1 gp41 is critical for viral fusion and entry.

    Directory of Open Access Journals (Sweden)

    Xiaoyi Wang

    Full Text Available During the process of HIV-1 fusion with the target cell, the N-terminal heptad repeat (NHR of gp41 interacts with the C-terminal heptad repeat (CHR to form fusogenic six-helix bundle (6-HB core. We previously identified a crucial residue for 6-HB formation and virus entry--Lys63 (K63 in the C-terminal region of NHR (aa 54-70, which forms a hydrophobic cavity. It can form an important salt bridge with Asp121 (D121 in gp41 CHR. Here, we found another important conserved residue for virus fusion and entry, Arg46 (R46, in the N-terminal region of NHR (aa 35-53, which forms a hydrogen bond with a polar residue, Asn43 (N43, in NHR, as a part of the hydrogen-bond network. R46 can also form a salt bridge with a negatively charged residue, Glu137 (E137, in gp41 CHR. Substitution of R46 with the hydrophobic residue Ala (R46A or the negatively charged residue Glu (R46E resulted in disruption of the hydrogen bond network, breakage of the salt bridge and reduction of 6-HB's stability, leading to impairment of viral fusion and decreased inhibition of N36, an NHR peptide. Similarly, CHR peptide C34 with substitution of E137 for Ala (E137A or Arg (E137R also exhibited reduced inhibitory activity against HIV-1 infection and HIV-1-mediated cell-to-cell fusion. These results suggest that the positively charged residue R46 and its hydrogen bond network, together with the salt bridge between R46 and E137, are important for viral fusion and entry and may therefore serve as a target for designing novel HIV fusion/entry inhibitors.

  2. HIV-1 tropism for the central nervous system: Brain-derived envelope glycoproteins with lower CD4 dependence and reduced sensitivity to a fusion inhibitor

    International Nuclear Information System (INIS)

    Martin-Garcia, Julio; Cao, Wei; Varela-Rohena, Angel; Plassmeyer, Matthew L.; Gonzalez-Scarano, Francisco

    2006-01-01

    We previously described envelope glycoproteins of an HIV-1 isolate adapted in vitro for growth in microglia that acquired a highly fusogenic phenotype and lower CD4 dependence, as well as resistance to inhibition by anti-CD4 antibodies. Here, we investigated whether similar phenotypic changes are present in vivo. Envelope clones from the brain and spleen of an HIV-1-infected individual with neurological disease were amplified, cloned, and sequenced. Phylogenetic analysis demonstrated clustering of sequences according to the tissue of origin, as expected. Functional clones were then used in cell-to-cell fusion assays to test for CD4 and co-receptor utilization and for sensitivity to various antibodies and inhibitors. Both brain- and spleen-derived envelope clones mediated fusion in cells expressing both CD4 and CCR5 and brain envelopes also used CCR3 as co-receptor. We found that the brain envelopes had a lower CD4 dependence, since they efficiently mediated fusion in the presence of low levels of CD4 on the target cell membrane, and they were significantly more resistant to blocking by anti-CD4 antibodies than the spleen-derived envelopes. In contrast, we observed no difference in sensitivity to the CCR5 antagonist TAK-779. However, brain-derived envelopes were significantly more resistant than those from spleen to the fusion inhibitor T-1249 and concurrently showed slightly greater fusogenicity. Our results suggest an increased affinity for CD4 of brain-derived envelopes that may have originated from in vivo adaptation to replication in microglial cells. Interestingly, we note the presence of envelopes more resistant to a fusion inhibitor in the brain of an untreated, HIV-1-infected individual

  3. Human antibody response to a strain-specific HIV-1 gp120 epitope associated with cell fusion inhibition

    NARCIS (Netherlands)

    Goudsmit, J.; Boucher, C. A.; Meloen, R. H.; Epstein, L. G.; Smit, L.; van der Hoek, L.; Bakker, M.

    1988-01-01

    PEPSCAN analysis, performed using 536 overlapping nonapeptides derived from the HTLV-III B nucleotide sequence of the region encoding the external envelope protein of 120 kDa (gp120), identified in the V3 region of gp120 a major binding site for antibodies of HIV-1-infected humans. The minimal amino

  4. Structural and Functional Analysis of HIV-1 Coreceptors: Roles of Charged Residues and Posttranslational Modifications on Coreceptor Activity

    National Research Council Canada - National Science Library

    Chabot, Donald

    2000-01-01

    .... To define these regions we have employed an alanine-scanning mutagenesis strategy of the extracellular domains of CXCR4 coupled with a highly sensitive reporter-gene assay for HIV-1 Env-mediated membrane fusion...

  5. Productive infection of human immunodeficiency virus type 1 in dendritic cells requires fusion-mediated viral entry

    International Nuclear Information System (INIS)

    Janas, Alicia M.; Dong, Chunsheng; Wang Jianhua; Wu Li

    2008-01-01

    Human immunodeficiency virus type 1 (HIV-1) enters dendritic cells (DCs) through endocytosis and viral receptor-mediated fusion. Although endocytosis-mediated HIV-1 entry can generate productive infection in certain cell types, including human monocyte-derived macrophages, productive HIV-1 infection in DCs appears to be dependent on fusion-mediated viral entry. It remains to be defined whether endocytosed HIV-1 in DCs can initiate productive infection. Using HIV-1 infection and cellular fractionation assays to measure productive viral infection and entry, here we show that HIV-1 enters monocyte-derived DCs predominately through endocytosis; however, endocytosed HIV-1 cannot initiate productive HIV-1 infection in DCs. In contrast, productive HIV-1 infection in DCs requires fusion-mediated viral entry. Together, these results provide functional evidence in understanding HIV-1 cis-infection of DCs, suggesting that different pathways of HIV-1 entry into DCs determine the outcome of viral infection

  6. Discovery of small-molecule HIV-1 fusion and integrase inhibitors oleuropein and hydroxytyrosol: Part II. Integrase inhibition

    International Nuclear Information System (INIS)

    Lee-Huang, Sylvia; Huang, Philip Lin; Zhang Dawei; Lee, Jae Wook; Bao Ju; Sun Yongtao; Chang, Young-Tae; Zhang, John; Huang, Paul Lee

    2007-01-01

    We report molecular modeling and functional confirmation of Ole and HT binding to HIV-1 integrase. Docking simulations identified two binding regions for Ole within the integrase active site. Region I encompasses the conserved D64-D116-E152 motif, while region II involves the flexible loop region formed by amino acid residues 140-149. HT, on the other hand, binds to region II. Both Ole and HT exhibit favorable interactions with important amino acid residues through strong H-bonding and van der Waals contacts, predicting integrase inhibition. To test and confirm modeling predictions, we examined the effect of Ole and HT on HIV-1 integrase activities including 3'-processing, strand transfer, and disintegration. Ole and HT exhibit dose-dependent inhibition on all three activities, with EC 50 s in the nanomolar range. These studies demonstrate that molecular modeling of target-ligand interaction coupled with structural-activity analysis should facilitate the design and identification of innovative integrase inhibitors and other therapeutics

  7. 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.

  8. Specific interaction of CXCR4 with CD4 and CD8α: Functional analysis of the CD4/CXCR4 interaction in the context of HIV-1 envelope glycoprotein-mediated membrane fusion

    International Nuclear Information System (INIS)

    Basmaciogullari, Stephane; Pacheco, Beatriz; Bour, Stephan; Sodroski, Joseph

    2006-01-01

    We investigated possible interactions between HIV-1 receptor (CD4) and the main coreceptors CXCR4 and CCR5. We found that CD4 and CXCR4 coexpressed in 293T cells form a complex that can be immunoprecipitated with antibodies directed against the extracellular domain of either protein. Mutagenesis revealed that the CD4/CXCR4 interaction maps to two previously uncharacterized basic motifs in the cytoplasmic domain of CD4. HIV-1 envelope glycoprotein-mediated membrane fusion was found to be independent of the ability of CD4 and CXCR4 to interact, whether fusion was studied in a virus-cell or a cell-cell model. However, this interaction might explain the adaptation of HIV-1 to CXCR4 as an alternative to CCR5. We found that CXCR4 also interacts with the cytoplasmic domain of CD8α in a way that is similar to the CD4/CXCR4 interaction. The CD4/CXCR4 and CD8α/CXCR4 interactions may thus be involved in cellular signaling pathways shared by the CD4 and CD8α molecules

  9. 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.

  10. First line treatment response in patients with transmitted HIV drug resistance and well defined time point of HIV infection: updated results from the German HIV-1 seroconverter study.

    Directory of Open Access Journals (Sweden)

    Fabia Zu Knyphausen

    Full Text Available BACKGROUND: Transmission of drug-resistant HIV-1 (TDR can impair the virologic response to antiretroviral combination therapy. Aim of the study was to assess the impact of TDR on treatment success of resistance test-guided first-line therapy in the German HIV-1 Seroconverter Cohort for patients infected with HIV between 1996 and 2010. An update of the prevalence of TDR and trend over time was performed. METHODS: Data of 1,667 HIV-infected individuals who seroconverted between 1996 and 2010 were analysed. The WHO drug resistance mutations list was used to identify resistance-associated HIV mutations in drug-naïve patients for epidemiological analysis. For treatment success analysis the Stanford algorithm was used to classify a subset of 323 drug-naïve genotyped patients who received a first-line cART into three resistance groups: patients without TDR, patients with TDR and fully active cART and patients with TDR and non-fully active cART. The frequency of virologic failure 5 to 12 months after treatment initiation was determined. RESULTS: Prevalence of TDR was stable at a high mean level of 11.9% (198/1,667 in the HIV-1 Seroconverter Cohort without significant trend over time. Nucleotide reverse transcriptase inhibitor resistance was predominant (6.0% and decreased significantly over time (OR = 0.92, CI = 0.87-0.98, p = 0.01. Non-nucleoside reverse transcriptase inhibitor (2.4%; OR = 1.00, CI = 0.92-1.09, p = 0.96 and protease inhibitor resistance (2.0%; OR = 0.94, CI = 0.861.03, p = 0.17 remained stable. Virologic failure was observed in 6.5% of patients with TDR receiving fully active cART, 5,6% of patients with TDR receiving non-fully active cART and 3.2% of patients without TDR. The difference between the three groups was not significant (p = 0.41. CONCLUSION: Overall prevalence of TDR remained stable at a rather high level. No significant differences in the frequency of virologic failure were

  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. Dendritic cell mediated delivery of plasmid DNA encoding LAMP/HIV-1 Gag fusion immunogen enhances T cell epitope responses in HLA DR4 transgenic mice.

    Directory of Open Access Journals (Sweden)

    Gregory G Simon

    2010-01-01

    Full Text Available This report describes the identification and bioinformatics analysis of HLA-DR4-restricted HIV-1 Gag epitope peptides, and the application of dendritic cell mediated immunization of DNA plasmid constructs. BALB/c (H-2d and HLA-DR4 (DRA1*0101, DRB1*0401 transgenic mice were immunized with immature dendritic cells transfected by a recombinant DNA plasmid encoding the lysosome-associated membrane protein-1/HIV-1 Gag (pLAMP/gag chimera antigen. Three immunization protocols were compared: 1 primary subcutaneous immunization with 1x10(5 immature dendritic cells transfected by electroporation with the pLAMP/gag DNA plasmid, and a second subcutaneous immunization with the naked pLAMP/gag DNA plasmid; 2 primary immunization as above, and a second subcutaneous immunization with a pool of overlapping peptides spanning the HIV-1 Gag sequence; and 3 immunization twice by subcutaneous injection of the pLAMP/gag DNA plasmid. Primary immunization with pLAMP/gag-transfected dendritic cells elicited the greatest number of peptide specific T-cell responses, as measured by ex vivo IFN-gamma ELISpot assay, both in BALB/c and HLA-DR4 transgenic mice. The pLAMP/gag-transfected dendritic cells prime and naked DNA boost immunization protocol also resulted in an increased apparent avidity of peptide in the ELISpot assay. Strikingly, 20 of 25 peptide-specific T-cell responses in the HLA-DR4 transgenic mice contained sequences that corresponded, entirely or partially to 18 of the 19 human HLA-DR4 epitopes listed in the HIV molecular immunology database. Selection of the most conserved epitope peptides as vaccine targets was facilitated by analysis of their representation and variability in all reported sequences. These data provide a model system that demonstrates a the superiority of immunization with dendritic cells transfected with LAMP/gag plasmid DNA, as compared to naked DNA, b the value of HLA transgenic mice as a model system for the identification and evaluation

  13. Fusion of Epstein-Barr virus nuclear antigen-1-derived glycine-alanine repeat to trans-dominant HIV-1 Gag increases inhibitory activities and survival of transduced cells in vivo.

    Science.gov (United States)

    Hammer, Diana; Wild, Jens; Ludwig, Christine; Asbach, Benedikt; Notka, Frank; Wagner, Ralf

    2008-06-01

    Trans-dominant human immunodeficiency virus type 1 (HIV-1) Gag derivatives have been shown to efficiently inhibit late steps of HIV-1 replication in vitro by interfering with Gag precursor assembly, thus ranking among the interesting candidates for gene therapy approaches. However, efficient antiviral activities of corresponding transgenes are likely to be counteracted in particular by cell-mediated host immune responses toward the transgene-expressing cells. To decrease this potential immunogenicity, a 24-amino acid Gly-Ala (GA) stretch derived from Epstein-Barr virus nuclear antigen-1 (EBNA1) and known to overcome proteasomal degradation was fused to a trans-dominant Gag variant (sgD1). To determine the capacity of this fusion polypeptide to repress viral replication, PM-1 cells were transduced with sgD1 and GAsgD1 transgenes, using retroviral gene transfer. Challenge of stably transfected permissive cell lines with various viral strains indicated that N-terminal GA fusion even enhanced the inhibitory properties of sgD1. Further studies revealed that the GA stretch increased protein stability by blocking proteasomal degradation of Gag proteins. Immunization of BALB/c mice with a DNA vaccine vector expressing sgD1 induced substantial Gag-specific immune responses that were, however, clearly diminished in the presence of GA. Furthermore, recognition of cells expressing the GA-fused transgene by CD8(+) T cells was drastically reduced, both in vitro and in vivo, resulting in prolonged survival of the transduced cells in recipient mice.

  14. 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

  15. Inhibition of HIV-1 infection by synthetic peptides derived CCR5 fragments

    International Nuclear Information System (INIS)

    Imai, Masaki; Baranyi, Lajos; Okada, Noriko; Okada, Hidechika

    2007-01-01

    HIV-1 infection requires interaction of viral envelope protein gp160 with CD4 and a chemokine receptor, CCR5 or CXCR4 as entry coreceptor. We designed HIV-inhibitory peptides targeted to CCR5 using a novel computer program (ANTIS), which searched all possible sense-antisense amino acid pairs between proteins. Seven AHBs were found in CCR5 receptor. All AHB peptides were synthesized and tested for their ability to prevent HIV-1 infection to human T cells. A peptide fragment (LC5) which is a part of the CCR5 receptor corresponding to the loop between the fifth and sixth transmembrane regions (amino acids 222-240) proved to inhibit HIV-1 IIIB infection of MT-4 cells. Interaction of these antisense peptides could be involved in sustaining HIV-1 infectivity. LC5 effectively indicated dose-dependent manner, and the suppression was enhanced additively by T20 peptide, which inhibits infection in vitro by disrupting the gp41 conformational changes necessary for membrane fusion. Thus, these results indicate that CCR5-derived AHB peptides could provide a useful tool to define the mechanism(s) of HIV infection, and may provide insight which will contribute to the development of an anti-HIV-1 reagent

  16. 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

  17. 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.

  18. An MHC-I cytoplasmic domain/HIV-1 Nef fusion protein binds directly to the mu subunit of the AP-1 endosomal coat complex.

    Directory of Open Access Journals (Sweden)

    Rajendra Kumar Singh

    2009-12-01

    Full Text Available The down-regulation of the major histocompatibility complex class I (MHC-I from the surface of infected cells by the Nef proteins of primate immunodeficiency viruses likely contributes to pathogenesis by providing evasion of cell-mediated immunity. HIV-1 Nef-induced down-regulation involves endosomal trafficking and a cooperative interaction between the cytoplasmic domain (CD of MHC-I, Nef, and the clathrin adaptor protein complex-1 (AP-1. The CD of MHC-I contains a key tyrosine within the sequence YSQA that is required for down-regulation by Nef, but this sequence does not conform to the canonical AP-binding tyrosine-based motif Yxxphi, which mediates binding to the medium (micro subunits of AP complexes. We previously proposed that Nef allows the MHC-I CD to bind the mu subunit of AP-1 (micro1 as if it contained a Yxxphimotif.Here, we show that a direct interaction between the MHC-I CD/Nef and micro1 plays a primary role in the down-regulation of MHC-I: GST pulldown assays using recombinant proteins indicated that most of the MHC-I CD and Nef residues that are required for the down-regulation in human cells contribute to direct interactions with a truncated version of micro1. Specifically, the tyrosine residue of the YSQA sequence in the MHC-I CD as well as Nef residues E62-65 and P78 each contributed to the interaction between MHC-I CD/Nef and micro1 in vitro, whereas Nef M20 had little to no role. Conversely, residues F172/D174 and V392/L395 of the binding pocket on micro1 for Yxxphi motifs were required for a robust interaction.These data indicate that the MHC-I cytoplasmic domain, Nef, and the C-terminal two thirds of the mu subunit of AP-1 are sufficient to constitute a biologically relevant interaction. The data also reveal an unexpected role for a hydrophobic pocket in micro1 for interaction with MHC-I CD/Nef.

  19. Genetic Characterization of a Novel HIV-1 Circulating Recombinant Form (CRF74_01B) Identified among Intravenous Drug Users in Malaysia: Recombination History and Phylogenetic Linkage with Previously Defined Recombinant Lineages.

    Science.gov (United States)

    Cheong, Hui Ting; Chow, Wei Zhen; Takebe, Yutaka; Chook, Jack Bee; Chan, Kok Gan; Al-Darraji, Haider Abdulrazzaq Abed; Koh, Clayton; Kamarulzaman, Adeeba; Tee, Kok Keng

    2015-01-01

    In many parts of Southeast Asia, the HIV-1 epidemic has been driven by the sharing of needles and equipment among intravenous drug users (IDUs). Over the last few decades, many studies have proven time and again that the diversity of HIV-1 epidemics can often be linked to the route of infection transmission. That said, the diversity and complexity of HIV-1 molecular epidemics in the region have been increasing at an alarming rate, due in part to the high tendency of the viral RNA to recombine. This scenario was exemplified by the discovery of numerous circulating recombinant forms (CRFs), especially in Thailand and Malaysia. In this study, we characterized a novel CRF designated CRF74_01B, which was identified in six epidemiologically unlinked IDUs in Kuala Lumpur, Malaysia. The near-full length genomes were composed of CRF01_AE and subtype B', with eight breakpoints dispersed in the gag-pol and nef regions. Remarkably, this CRF shared four and two recombination hotspots with the previously described CRF33_01B and the less prevalent CRF53_01B, respectively. Genealogy-based Bayesian phylogenetic analysis of CRF74_01B genomic regions showed that it is closely related to both CRF33_01B and CRF53_01B. This observation suggests that CRF74_01B was probably a direct descendent from specific lineages of CRF33_01B, CRF53_01B and subtype B' that could have emerged in the mid-1990s. Additionally, it illustrated the active recombination processes between prevalent HIV-1 subtypes and recombinants in Malaysia. In summary, we report a novel HIV-1 genotype designated CRF74_01B among IDUs in Kuala Lumpur, Malaysia. The characterization of the novel CRF74_01B is of considerable significance towards the understanding of the genetic diversity and population dynamics of HIV-1 circulating in the region.

  20. Genetic Characterization of a Novel HIV-1 Circulating Recombinant Form (CRF74_01B Identified among Intravenous Drug Users in Malaysia: Recombination History and Phylogenetic Linkage with Previously Defined Recombinant Lineages.

    Directory of Open Access Journals (Sweden)

    Hui Ting Cheong

    Full Text Available In many parts of Southeast Asia, the HIV-1 epidemic has been driven by the sharing of needles and equipment among intravenous drug users (IDUs. Over the last few decades, many studies have proven time and again that the diversity of HIV-1 epidemics can often be linked to the route of infection transmission. That said, the diversity and complexity of HIV-1 molecular epidemics in the region have been increasing at an alarming rate, due in part to the high tendency of the viral RNA to recombine. This scenario was exemplified by the discovery of numerous circulating recombinant forms (CRFs, especially in Thailand and Malaysia. In this study, we characterized a novel CRF designated CRF74_01B, which was identified in six epidemiologically unlinked IDUs in Kuala Lumpur, Malaysia. The near-full length genomes were composed of CRF01_AE and subtype B', with eight breakpoints dispersed in the gag-pol and nef regions. Remarkably, this CRF shared four and two recombination hotspots with the previously described CRF33_01B and the less prevalent CRF53_01B, respectively. Genealogy-based Bayesian phylogenetic analysis of CRF74_01B genomic regions showed that it is closely related to both CRF33_01B and CRF53_01B. This observation suggests that CRF74_01B was probably a direct descendent from specific lineages of CRF33_01B, CRF53_01B and subtype B' that could have emerged in the mid-1990s. Additionally, it illustrated the active recombination processes between prevalent HIV-1 subtypes and recombinants in Malaysia. In summary, we report a novel HIV-1 genotype designated CRF74_01B among IDUs in Kuala Lumpur, Malaysia. The characterization of the novel CRF74_01B is of considerable significance towards the understanding of the genetic diversity and population dynamics of HIV-1 circulating in the region.

  1. Identification of novel targets for HIV-1: Molecular dynamics simulation and binding energy calculations

    Science.gov (United States)

    Pandey, Vishnudatt; Tiwari, Gargi; Mall, Vijaya Shri; Tiwari, Rakesh Kumar; Ojha, R. P.

    2018-05-01

    HIV-1 envelope glycoprotein-mediated fusion is managed by the concerted coalescence of the HIV-1 gp41 N- and C- helical regions, which is a product in the formation of 6-helix bundles. These two regions are considered prime targets for peptides and antibodies that inhibit HIV-1 entry. There are so many rational method aimed to attach a rationally designed artificial tail to the C-terminus of HIV-1 fusion inhibitors to increase their antiviral potency. Here M. D. simulation was performed to go insight for study of C-terminal tail of Ile-Asp-Leu (IDL).

  2. Clustered epitopes within the Gag-Pol fusion protein DNA vaccine enhance immune responses and protection against challenge with recombinant vaccinia viruses expressing HIV-1 Gag and Pol antigens

    International Nuclear Information System (INIS)

    Bolesta, Elizabeth; Gzyl, Jaroslaw; Wierzbicki, Andrzej; Kmieciak, Dariusz; Kowalczyk, Aleksandra; Kaneko, Yutaro; Srinivasan, Alagarsamy; Kozbor, Danuta

    2005-01-01

    We have generated a codon-optimized hGagp17p24-Polp51 plasmid DNA expressing the human immunodeficiency virus type 1 (HIV-1) Gag-Pol fusion protein that consists of clusters of highly conserved cytotoxic T lymphocyte (CTL) epitopes presented by multiple MHC class I alleles. In the hGagp17p24-Polp51 construct, the ribosomal frameshift site had been deleted together with the potentially immunosuppressive Gag nucleocapsid (p15) as well as Pol protease (p10) and integrase (p31). Analyses of the magnitude and breadth of cellular responses demonstrated that immunization of HLA-A2/K b transgenic mice with the hGagp17p24-Polp51 construct induced 2- to 5-fold higher CD8 + T-cell responses to Gag p17-, p24-, and Pol reverse transcriptase (RT)-specific CTL epitopes than the full-length hGag-PolΔFsΔPr counterpart. The increases were correlated with higher protection against challenge with recombinant vaccinia viruses (rVVs) expressing gag and pol gene products. Consistent with the profile of Gag- and Pol-specific CD8 + T cell responses, an elevated level of type 1 cytokine production was noted in p24- and RT-stimulated splenocyte cultures established from hGagp17p24-Polp51-immunized mice compared to responses induced with the hGag-PolΔFsΔPr vaccine. Sera of mice immunized with the hGagp17p24-Polp51 vaccine also exhibited an increased titer of p24- and RT-specific IgG2 antibody responses. The results from our studies provide insights into approaches for boosting the breadth of Gag- and Pol-specific immune responses

  3. 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.

  4. 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.

  5. Immunodominant B-cell clones responsive to an HIV-1 neutralization and cell fusion inhibition epitope in chimpanzee-to-chimpanzee passages of HTLV-IIIB and LAV-1

    NARCIS (Netherlands)

    Goudsmit, J.; Bakker, M.; Smit, L.

    1989-01-01

    Chimpanzees infected with the HIV-1 strains HTLV-IIIB or LAV-1 in primary, secondary or tertiary passages developed neutralizing antibodies binding to variable domain V3 in the carboxyl terminal half of the external envelope (amino acids 309-317). Nonapeptide antigens reflecting either the

  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. HIV-1 and the macrophage

    NARCIS (Netherlands)

    Bol, Sebastiaan M.; Cobos-Jimenez, Viviana; Kootstra, Neeltje A.; van 't Wout, Angelique B.

    2011-01-01

    Macrophages and CD4(+) T cells are natural target cells for HIV-1, and both cell types contribute to the establishment of the viral reservoir that is responsible for continuous residual virus replication during antiretroviral therapy and viral load rebound upon treatment interruption. Scientific

  8. 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

  9. 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

  10. 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

  11. 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...

  12. Therapeutic doses of irradiation activate viral transcription and induce apoptosis in HIV-1 infected cells

    International Nuclear Information System (INIS)

    Iordanskiy, Sergey; Van Duyne, Rachel; Sampey, Gavin C; Woodson, Caitlin M; Fry, Kelsi; Saifuddin, Mohammed; Guo, Jia; Wu, Yuntao; Romerio, Fabio; Kashanchi, Fatah

    2015-01-01

    The highly active antiretroviral therapy reduces HIV-1 RNA in plasma to undetectable levels. However, the virus continues to persist in the long-lived resting CD4"+ T cells, macrophages and astrocytes which form a viral reservoir in infected individuals. Reactivation of viral transcription is critical since the host immune response in combination with antiretroviral therapy may eradicate the virus. Using the chronically HIV-1 infected T lymphoblastoid and monocytic cell lines, primary quiescent CD4"+ T cells and humanized mice infected with dual-tropic HIV-1 89.6, we examined the effect of various X-ray irradiation (IR) doses (used for HIV-related lymphoma treatment and lower doses) on HIV-1 transcription and viability of infected cells. Treatment of both T cells and monocytes with IR, a well-defined stress signal, led to increase of HIV-1 transcription, as evidenced by the presence of RNA polymerase II and reduction of HDAC1 and methyl transferase SUV39H1 on the HIV-1 promoter. This correlated with the increased GFP signal and elevated level of intracellular HIV-1 RNA in the IR-treated quiescent CD4"+ T cells infected with GFP-encoding HIV-1. Exposition of latently HIV-1infected monocytes treated with PKC agonist bryostatin 1 to IR enhanced transcription activation effect of this latency-reversing agent. Increased HIV-1 replication after IR correlated with higher cell death: the level of phosphorylated Ser46 in p53, responsible for apoptosis induction, was markedly higher in the HIV-1 infected cells following IR treatment. Exposure of HIV-1 infected humanized mice with undetectable viral RNA level to IR resulted in a significant increase of HIV-1 RNA in plasma, lung and brain tissues. Collectively, these data point to the use of low to moderate dose of IR alone or in combination with HIV-1 transcription activators as a potential application for the “Shock and Kill” strategy for latently HIV-1 infected cells. - Highlights: • X-ray irradiation (IR) increases

  13. Therapeutic doses of irradiation activate viral transcription and induce apoptosis in HIV-1 infected cells

    Energy Technology Data Exchange (ETDEWEB)

    Iordanskiy, Sergey [School of Systems Biology, Laboratory of Molecular Virology, George Mason University, Manassas, VA 20110 (United States); Van Duyne, Rachel [School of Systems Biology, Laboratory of Molecular Virology, George Mason University, Manassas, VA 20110 (United States); Center for Cancer Research, National Cancer Institute, National Institutes of Health, Frederick, MD 21702 (United States); Sampey, Gavin C; Woodson, Caitlin M; Fry, Kelsi; Saifuddin, Mohammed; Guo, Jia; Wu, Yuntao [School of Systems Biology, Laboratory of Molecular Virology, George Mason University, Manassas, VA 20110 (United States); Romerio, Fabio [Department of Medicine, University of Maryland School of Medicine, Baltimore, MD 21201 (United States); Kashanchi, Fatah, E-mail: fkashanc@gmu.edu [School of Systems Biology, Laboratory of Molecular Virology, George Mason University, Manassas, VA 20110 (United States)

    2015-11-15

    The highly active antiretroviral therapy reduces HIV-1 RNA in plasma to undetectable levels. However, the virus continues to persist in the long-lived resting CD4{sup +} T cells, macrophages and astrocytes which form a viral reservoir in infected individuals. Reactivation of viral transcription is critical since the host immune response in combination with antiretroviral therapy may eradicate the virus. Using the chronically HIV-1 infected T lymphoblastoid and monocytic cell lines, primary quiescent CD4{sup +} T cells and humanized mice infected with dual-tropic HIV-1 89.6, we examined the effect of various X-ray irradiation (IR) doses (used for HIV-related lymphoma treatment and lower doses) on HIV-1 transcription and viability of infected cells. Treatment of both T cells and monocytes with IR, a well-defined stress signal, led to increase of HIV-1 transcription, as evidenced by the presence of RNA polymerase II and reduction of HDAC1 and methyl transferase SUV39H1 on the HIV-1 promoter. This correlated with the increased GFP signal and elevated level of intracellular HIV-1 RNA in the IR-treated quiescent CD4{sup +} T cells infected with GFP-encoding HIV-1. Exposition of latently HIV-1infected monocytes treated with PKC agonist bryostatin 1 to IR enhanced transcription activation effect of this latency-reversing agent. Increased HIV-1 replication after IR correlated with higher cell death: the level of phosphorylated Ser46 in p53, responsible for apoptosis induction, was markedly higher in the HIV-1 infected cells following IR treatment. Exposure of HIV-1 infected humanized mice with undetectable viral RNA level to IR resulted in a significant increase of HIV-1 RNA in plasma, lung and brain tissues. Collectively, these data point to the use of low to moderate dose of IR alone or in combination with HIV-1 transcription activators as a potential application for the “Shock and Kill” strategy for latently HIV-1 infected cells. - Highlights: • X-ray irradiation

  14. Escherichia coli surface display of single-chain antibody VRC01 against HIV-1 infection

    International Nuclear Information System (INIS)

    Wang, Lin-Xu; Mellon, Michael; Bowder, Dane; Quinn, Meghan; Shea, Danielle; Wood, Charles; Xiang, Shi-Hua

    2015-01-01

    Human immunodeficiency virus type 1 (HIV-1) transmission and infection occur mainly via the mucosal surfaces. The commensal bacteria residing in these surfaces can potentially be employed as a vehicle for delivering inhibitors to prevent HIV-1 infection. In this study, we have employed a bacteria-based strategy to display a broadly neutralizing antibody VRC01, which could potentially be used to prevent HIV-1 infection. The VRC01 antibody mimics CD4-binding to gp120 and has broadly neutralization activities against HIV-1. We have designed a construct that can express the fusion peptide of the scFv-VRC01 antibody together with the autotransporter β-barrel domain of IgAP gene from Neisseria gonorrhoeae, which enabled surface display of the antibody molecule. Our results indicate that the scFv-VRC01 antibody molecule was displayed on the surface of the bacteria as demonstrated by flow cytometry and immunofluorescence microscopy. The engineered bacteria can capture HIV-1 particles via surface-binding and inhibit HIV-1 infection in cell culture. - Highlights: • Designed single-chain VRC01 antibody was demonstrated to bind HIV-1 envelope gp120. • Single-chain VRC01 antibody was successfully displayed on the surface of E. coli. • Engineered bacteria can absorb HIV-1 particles and prevent HIV-1 infection in cell culture

  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. 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.

  17. 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.

  18. Fusion

    CERN Document Server

    Mahaffey, James A

    2012-01-01

    As energy problems of the world grow, work toward fusion power continues at a greater pace than ever before. The topic of fusion is one that is often met with the most recognition and interest in the nuclear power arena. Written in clear and jargon-free prose, Fusion explores the big bang of creation to the blackout death of worn-out stars. A brief history of fusion research, beginning with the first tentative theories in the early 20th century, is also discussed, as well as the race for fusion power. This brand-new, full-color resource examines the various programs currently being funded or p

  19. 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

    HIV-1 viral particles, our findings define a functional HIV-1 packaging system as comprising the 5' UTR cis elements, Gag, and the Rev/RRE system, in which the Rev/RRE system is required to make the RNA amenable to the ensuing interaction between Gag and the canonical packaging signal for subsequent encapsidation.

  20. Engineering Cellular Resistance to HIV-1 Infection In Vivo Using a Dual Therapeutic Lentiviral Vector

    Directory of Open Access Journals (Sweden)

    Bryan P Burke

    2015-01-01

    Full Text Available We described earlier a dual-combination anti-HIV type 1 (HIV-1 lentiviral vector (LVsh5/C46 that downregulates CCR5 expression of transduced cells via RNAi and inhibits HIV-1 fusion via cell surface expression of cell membrane-anchored C46 antiviral peptide. This combinatorial approach has two points of inhibition for R5-tropic HIV-1 and is also active against X4-tropic HIV-1. Here, we utilize the humanized bone marrow, liver, thymus (BLT mouse model to characterize the in vivo efficacy of LVsh5/C46 (Cal-1 vector to engineer cellular resistance to HIV-1 pathogenesis. Human CD34+ hematopoietic stem/progenitor cells (HSPC either nonmodified or transduced with LVsh5/C46 vector were transplanted to generate control and treatment groups, respectively. Control and experimental groups displayed similar engraftment and multilineage hematopoietic differentiation that included robust CD4+ T-cell development. Splenocytes isolated from the treatment group were resistant to both R5- and X4-tropic HIV-1 during ex vivo challenge experiments. Treatment group animals challenged with R5-tropic HIV-1 displayed significant protection of CD4+ T-cells and reduced viral load within peripheral blood and lymphoid tissues up to 14 weeks postinfection. Gene-marking and transgene expression were confirmed stable at 26 weeks post-transplantation. These data strongly support the use of LVsh5/C46 lentiviral vector in gene and cell therapeutic applications for inhibition of HIV-1 infection.

  1. Membrane topology analysis of HIV-1 envelope glycoprotein gp41

    Directory of Open Access Journals (Sweden)

    Xiao Dan

    2010-11-01

    Full Text Available Abstract Background The gp41 subunit of the HIV-1 envelope glycoprotein (Env has been widely regarded as a type I transmembrane protein with a single membrane-spanning domain (MSD. An alternative topology model suggested multiple MSDs. The major discrepancy between the two models is that the cytoplasmic Kennedy sequence in the single MSD model is assigned as the extracellular loop accessible to neutralizing antibodies in the other model. We examined the membrane topology of the gp41 subunit in both prokaryotic and mammalian systems. We attached topological markers to the C-termini of serially truncated gp41. In the prokaryotic system, we utilized a green fluorescent protein (GFP that is only active in the cytoplasm. The tag protein (HaloTag and a membrane-impermeable ligand specific to HaloTag was used in the mammalian system. Results In the absence of membrane fusion, both the prokaryotic and mammalian systems (293FT cells supported the single MSD model. In the presence of membrane fusion in mammalian cells (293CD4 cells, the data obtained seem to support the multiple MSD model. However, the region predicted to be a potential MSD is the highly hydrophilic Kennedy sequence and is least likely to become a MSD based on several algorithms. Further analysis revealed the induction of membrane permeability during membrane fusion, allowing the membrane-impermeable ligand and antibodies to cross the membrane. Therefore, we cannot completely rule out the possible artifacts. Addition of membrane fusion inhibitors or alterations of the MSD sequence decreased the induction of membrane permeability. Conclusions It is likely that a single MSD model for HIV-1 gp41 holds true even in the presence of membrane fusion. The degree of the augmentation of membrane permeability we observed was dependent on the membrane fusion and sequence of the MSD.

  2. 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.

  3. Defining the interactions and role of DCAF1/VPRBP in the DDB1-cullin4A E3 ubiquitin ligase complex engaged by HIV-1 Vpr to induce a G2 cell cycle arrest.

    Directory of Open Access Journals (Sweden)

    Francine C A Gérard

    Full Text Available HIV viral protein R (Vpr induces a cell cycle arrest at the G2/M phase by activating the ATR DNA damage/replication stress signalling pathway through engagement of the DDB1-CUL4A-DCAF1 E3 ubiquitin ligase via a direct binding to the substrate specificity receptor DCAF1. Since no high resolution structures of the DDB1-DCAF1-Vpr substrate recognition module currently exist, we used a mutagenesis approach to better define motifs in DCAF1 that are crucial for Vpr and DDB1 binding. Herein, we show that the minimal domain of DCAF1 that retained the ability to bind Vpr and DDB1 was mapped to residues 1041 to 1393 (DCAF1 WD. Mutagenic analyses identified an α-helical H-box motif and F/YxxF/Y motifs located in the N-terminal domain of DCAF1 WD that are involved in exclusive binding to DDB1. While we could not identify elements specifically involved in Vpr binding, overall, the mutagenesis data suggest that the predicted β-propeller conformation of DCAF1 is likely to be critical for Vpr association. Importantly, we provide evidence that binding of Vpr to DCAF1 appears to modulate the formation of a DDB1/DCAF1 complex. Lastly, we show that expression of DCAF1 WD in the absence of endogenous DCAF1 was not sufficient to enable Vpr-mediated G2 arrest activity. Overall, our results reveal that Vpr and DDB1 binding on DCAF1 can be genetically separated and further suggest that DCAF1 contains determinants in addition to the Vpr and DDB1 minimal binding domain, which are required for Vpr to enable the induction of a G2 arrest.

  4. Construction of Nef-positive doxycycline-dependent HIV-1 variants using bicistronic expression elements

    Energy Technology Data Exchange (ETDEWEB)

    Velden, Yme U. van der; Kleibeuker, Wendy; Harwig, Alex; Klaver, Bep; Siteur-van Rijnstra, Esther; Frankin, Esmay; Berkhout, Ben; Das, Atze T., E-mail: a.t.das@amc.uva.nl

    2016-01-15

    Conditionally replicating HIV-1 variants that can be switched on and off at will are attractive tools for HIV research. We previously developed a genetically modified HIV-1 variant that replicates exclusively when doxycycline (dox) is administered. The nef gene in this HIV-rtTA variant was replaced with the gene encoding the dox-dependent rtTA transcriptional activator. Because loss of Nef expression compromises virus replication in primary cells and precludes studies on Nef function, we tested different approaches to restore Nef production in HIV-rtTA. Strategies that involved translation via an EMCV or synthetic internal ribosome entry site (IRES) failed because these elements were incompatible with efficient virus replication. Fusion protein approaches with the FMDV 2A peptide and human ubiquitin were successful and resulted in genetically-stable Nef-expressing HIV-rtTA strains that replicate more efficiently in primary T-cells and human immune system (HIS) mice than Nef-deficient variants, thus confirming the positive effect of Nef on in vivo virus replication. - Highlights: • Different approaches to encode additional proteins in the HIV-1 genome were tested. • IRES translation elements are incompatible with efficient HIV-1 replication. • Ubiquitin and 2A fusion protein approaches allow efficient HIV-1 replication. • Doxycycline-controlled HIV-1 variants that encode all viral proteins were developed. • Nef stimulates HIV-rtTA replication in primary cells and human immune system mice.

  5. 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.

  6. Maturation Pathways of Cross-Reactive HIV-1 Neutralizing Antibodies

    Directory of Open Access Journals (Sweden)

    Dimiter S. Dimitrov

    2009-11-01

    Full Text Available Several human monoclonal antibodies (hmAbs and antibody fragments, including the best characterized in terms of structure-function b12 and Fab X5, exhibit relatively potent and broad HIV-1 neutralizing activity. However, the elicitation of b12 or b12-like antibodies in vivo by vaccine immunogens based on the HIV-1 envelope glycoprotein (Env has not been successful. B12 is highly divergent from the closest corresponding germline antibody while X5 is less divergent. We have hypothesized that the relatively high degree of specific somatic hypermutations may preclude binding of the HIV-1 envelope glycoprotein (Env to closest germline antibodies, and that identifying antibodies that are intermediates in the pathways to maturation could help design novel vaccine immunogens to guide the immune system for their enhanced elicitation. In support of this hypothesis we have previously found that a germline-like b12 (monovalent and bivalent scFv as an Fc fusion protein or IgG lacks measurable binding to an Env as measured by ELISA with a sensitivity in the μM range [1]; here we present evidence confirming and expanding these findings for a panel of Envs. In contrast, a germline-like scFv X5 bound Env with high (nM affinity. To begin to explore the maturation pathways of these antibodies we identified several possible b12 intermediate antibodies and tested their neutralizing activity. These intermediate antibodies neutralized only some HIV-1 isolates and with relatively weak potency. In contrast, germline-like scFv X5 neutralized a subset of the tested HIV-1 isolates with comparable efficiencies to that of the mature X5. These results could help explain the relatively high immunogenicity of the coreceptor binding site on gp120 and the abundance of CD4-induced (CD4i antibodies in HIV-1-infected patients (X5 is a CD4i antibody as well as the maturation pathway of X5. They also can help identify antigens that can bind specifically to b12 germline and

  7. 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.

  8. Biased small-molecule ligands for selective inhibition of HIV-1 cell entry via CCR5

    DEFF Research Database (Denmark)

    Berg, Christian; Spiess, Katja; von Lüttichau, Hans Rudolf

    2016-01-01

    Since the discovery of HIV's use of CCR5 as the primary coreceptor in fusion, the focus on developing small-molecule receptor antagonists for inhibition hereof has only resulted in one single drug, Maraviroc. We therefore investigated the possibility of using small-molecule CCR5 agonists as HIV-1...

  9. 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.

  10. 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.

  11. 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

  12. A prospective study of vaginal trichomoniasis and HIV-1 shedding in women on antiretroviral therapy

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    Masese Linnet N

    2011-11-01

    Full Text Available Abstract Background Trichomonas vaginalis has been associated with increased vaginal HIV-1 RNA shedding in antiretroviral therapy (ART-naïve women. The effect of trichomoniasis on vaginal HIV-1 shedding in ART-treated women has not been characterized. We tested the hypothesis that T. vaginalis infection would increase vaginal HIV-1 RNA shedding in women on ART, and that successful treatment would reduce vaginal HIV-1 RNA levels. Methods We conducted a prospective cohort study including monthly follow-up of 147 women receiving ART in Mombasa, Kenya. Those with T. vaginalis infection, defined by the presence of motile trichomonads on vaginal saline wet mount, received treatment with single dose metronidazole (2 g. Test of cure was performed at the next monthly visit. Using the pre-infection visit as the reference category, we compared detection of vaginal HIV-1 RNA before versus during and after infection using generalized estimating equations. A cut-off of 100 HIV-1 RNA copies/swab was used as the lower limit for linear quantitation. Results Among 31 women treated for trichomoniasis, the concentration of vaginal HIV-1 RNA was above the limit for quantitation before, during, and after T. vaginalis infection in 4 (13% [95% CI 4% - 30%], 4 (13% [95% CI 4% - 30%], and 5 (16% [95% confidence interval {CI} 5% - 34%] women respectively. After adjusting for potential confounding factors, we could detect no difference in the likelihood of detecting vaginal HIV-1 RNA before versus during infection (odds ratio [OR] 1.41, 95% CI 0.23 - 8.79, p = 0.7. In addition, detection of HIV-1 RNA was similar before infection versus after successful treatment (OR 0.68, 95% CI (0.13 - 3.45, p = 0.6. Conclusion Detection of vaginal HIV-1 RNA during ART was uncommon at visits before, during and after T. vaginalis infection.

  13. Nef enhances HIV-1 infectivity via association with the virus assembly complex

    International Nuclear Information System (INIS)

    Qi Mingli; Aiken, Christopher

    2008-01-01

    The HIV-1 accessory protein Nef enhances virus infectivity by facilitating an early post-entry step of infection. Nef acts in the virus producer cell, leading to a beneficial modification to HIV-1 particles. Nef itself is incorporated into HIV-1 particles, where it is cleaved by the viral protease during virion maturation. To probe the role of virion-associated Nef in HIV-1 infection, we generated a fusion protein consisting of the host protein cyclophilin A (CypA) linked to the amino terminus of Nef. The resulting CypA-Nef protein enhanced the infectivity of Nef-defective HIV-1 particles and was specifically incorporated into the virions via association with Gag during particle assembly. Pharmacologic or genetic inhibition of CypA-Nef binding to Gag prevented incorporation of CypA-Nef into virions and inhibited infectivity enhancement. Our results indicate that infectivity enhancement by Nef requires its association with a component of the assembling HIV-1 particle

  14. An efficient procedure for the expression and purification of HIV-1 protease from inclusion bodies.

    Science.gov (United States)

    Nguyen, Hong-Loan Thi; Nguyen, Thuy Thi; Vu, Quy Thi; Le, Hang Thi; Pham, Yen; Trinh, Phuong Le; Bui, Thuan Phuong; Phan, Tuan-Nghia

    2015-12-01

    Several studies have focused on HIV-1 protease for developing drugs for treating AIDS. Recombinant HIV-1 protease is used to screen new drugs from synthetic compounds or natural substances. However, large-scale expression and purification of this enzyme is difficult mainly because of its low expression and solubility. In this study, we constructed 9 recombinant plasmids containing a sequence encoding HIV-1 protease along with different fusion tags and examined the expression of the enzyme from these plasmids. Of the 9 plasmids, pET32a(+) plasmid containing the HIV-1 protease-encoding sequence along with sequences encoding an autocleavage site GTVSFNF at the N-terminus and TEV plus 6× His tag at the C-terminus showed the highest expression of the enzyme and was selected for further analysis. The recombinant protein was isolated from inclusion bodies by using 2 tandem Q- and Ni-Sepharose columns. SDS-PAGE of the obtained HIV-1 protease produced a single band of approximately 13 kDa. The enzyme was recovered efficiently (4 mg protein/L of cell culture) and had high specific activity of 1190 nmol min(-1) mg(-1) at an optimal pH of 4.7 and optimal temperature of 37 °C. This procedure for expressing and purifying HIV-1 protease is now being scaled up to produce the enzyme on a large scale for its application. Copyright © 2015 Elsevier Inc. All rights reserved.

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

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    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

  16. Production and characterization of human anti-V3 monoclonal antibodies from the cells of HIV-1 infected Indian donors

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    Andrabi Raiees

    2012-09-01

    Full Text Available Abstract Background Analysis of human monoclonal antibodies (mAbs developed from HIV-1 infected donors have enormously contributed to the identification of neutralization sensitive epitopes on the HIV-1 envelope glycoprotein. The third variable region (V3 is a crucial target on gp120, primarily due to its involvement in co-receptor (CXCR4 or CCR5 binding and presence of epitopes recognized by broadly neutralizing antibodies. Methods Thirty-three HIV-1 seropositive drug naive patients (18 males and 15 females within the age range of 20–57 years (median = 33 years were recruited in this study for mAb production. The mAbs were selected from EBV transformed cultures with conformationally constrained Cholera-toxin-B containing V3C (V3C-CTB fusion protein. We tested the mAbs for their binding with HIV-1 derived proteins and peptides by ELISA and for neutralization against HIV-1 viruses by TZM-bl assays. Results We isolated three anti-V3 mAbs, 277, 903 and 904 from the cells of different individuals. The ELISA binding revealed a subtype-C and subtype-A specific binding of antibody 277 and 903 while mAb 904 exhibited cross reactivity also with subtype-B V3. Epitope mapping of mAbs with overlapping V3 peptides showed exclusive binding to V3 crown. The antibodies displayed high and low neutralizing activity against 2/5 tier 1 and 1/6 tier 2 viruses respectively. Overall, we observed a resistance of the tier 2 viruses to neutralization by the anti-V3 mAbs, despite the exposure of the epitopes recognized by these antibodies on two representative native viruses (Du156.12 and JRFL, suggesting that the affinity of mAb might equally be crucial for neutralization, as the epitope recognition. Conclusions Our study suggests that the anti-V3 antibodies derived from subtype-C infected Indian patients display neutralization potential against tier 1 viruses while such activity may be limited against more resistant tier 2 viruses. Defining the fine epitope

  17. Predicting HIV-1 transmission and antibody neutralization efficacy in vivo from stoichiometric parameters.

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    Oliver F Brandenberg

    2017-05-01

    Full Text Available The potential of broadly neutralizing antibodies targeting the HIV-1 envelope trimer to prevent HIV-1 transmission has opened new avenues for therapies and vaccines. However, their implementation remains challenging and would profit from a deepened mechanistic understanding of HIV-antibody interactions and the mucosal transmission process. In this study we experimentally determined stoichiometric parameters of the HIV-1 trimer-antibody interaction, confirming that binding of one antibody is sufficient for trimer neutralization. This defines numerical requirements for HIV-1 virion neutralization and thereby enables mathematical modelling of in vitro and in vivo antibody neutralization efficacy. The model we developed accurately predicts antibody efficacy in animal passive immunization studies and provides estimates for protective mucosal antibody concentrations. Furthermore, we derive estimates of the probability for a single virion to start host infection and the risks of male-to-female HIV-1 transmission per sexual intercourse. Our work thereby delivers comprehensive quantitative insights into both the molecular principles governing HIV-antibody interactions and the initial steps of mucosal HIV-1 transmission. These insights, alongside the underlying, adaptable modelling framework presented here, will be valuable for supporting in silico pre-trial planning and post-hoc evaluation of HIV-1 vaccination or antibody treatment trials.

  18. Anti-gp120 minibody gene transfer to female genital epithelial cells protects against HIV-1 virus challenge in vitro.

    Directory of Open Access Journals (Sweden)

    Ussama M Abdel-Motal

    Full Text Available Although cervico-vaginal epithelial cells of the female lower genital tract provide the initial defense system against HIV-1 infection, the protection is sometimes incomplete. Thus, enhancing anti-HIV-1 humoral immunity at the mucosal cell surface by local expression of anti-HIV-1 broadly neutralizing antibodies (BnAb that block HIV-1 entry would provide an important new intervention that could slow the spread of HIV/AIDS.This study tested the hypothesis that adeno-associated virus (AAV-BnAb gene transfer to cervico-vaginal epithelial cells will lead to protection against HIV-1. Accordingly, a recombinant AAV vector that encodes human b12 anti-HIV gp120 BnAb as a single-chain variable fragment Fc fusion (scFvFc, or "minibody" was constructed. The secreted b12 minibody was shown to be biologically functional in binding to virus envelope protein, neutralizing HIV-1 and importantly, blocking transfer and infectivity of HIV-1(bal in an organotypic human vaginal epithelial cell (VEC model. Furthermore, cervico-vaginal epithelial stem cells were found to be efficiently transduced by the optimal AAV serotype mediated expression of GFP.This study provides the foundation for a novel microbicide strategy to protect against sexual transmission of HIV-1 by AAV transfer of broadly neutralizing antibody genes to cervico-vaginal epithelial stem cells that could replenish b12 BnAb secreting cells through multiple menstrual cycles.

  19. 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

  20. 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.

  1. Antibody-Mediated Internalization of Infectious HIV-1 Virions Differs among Antibody Isotypes and Subclasses.

    Science.gov (United States)

    Tay, Matthew Zirui; Liu, Pinghuang; Williams, LaTonya D; McRaven, Michael D; Sawant, Sheetal; Gurley, Thaddeus C; Xu, Thomas T; Dennison, S Moses; Liao, Hua-Xin; Chenine, Agnès-Laurence; Alam, S Munir; Moody, M Anthony; Hope, Thomas J; Haynes, Barton F; Tomaras, Georgia D

    2016-08-01

    Emerging data support a role for antibody Fc-mediated antiviral activity in vaccine efficacy and in the control of HIV-1 replication by broadly neutralizing antibodies. Antibody-mediated virus internalization is an Fc-mediated function that may act at the portal of entry whereby effector cells may be triggered by pre-existing antibodies to prevent HIV-1 acquisition. Understanding the capacity of HIV-1 antibodies in mediating internalization of HIV-1 virions by primary monocytes is critical to understanding their full antiviral potency. Antibody isotypes/subclasses differ in functional profile, with consequences for their antiviral activity. For instance, in the RV144 vaccine trial that achieved partial efficacy, Env IgA correlated with increased risk of HIV-1 infection (i.e. decreased vaccine efficacy), whereas V1-V2 IgG3 correlated with decreased risk of HIV-1 infection (i.e. increased vaccine efficacy). Thus, understanding the different functional attributes of HIV-1 specific IgG1, IgG3 and IgA antibodies will help define the mechanisms of immune protection. Here, we utilized an in vitro flow cytometric method utilizing primary monocytes as phagocytes and infectious HIV-1 virions as targets to determine the capacity of Env IgA (IgA1, IgA2), IgG1 and IgG3 antibodies to mediate HIV-1 infectious virion internalization. Importantly, both broadly neutralizing antibodies (i.e. PG9, 2G12, CH31, VRC01 IgG) and non-broadly neutralizing antibodies (i.e. 7B2 mAb, mucosal HIV-1+ IgG) mediated internalization of HIV-1 virions. Furthermore, we found that Env IgG3 of multiple specificities (i.e. CD4bs, V1-V2 and gp41) mediated increased infectious virion internalization over Env IgG1 of the same specificity, while Env IgA mediated decreased infectious virion internalization compared to IgG1. These data demonstrate that antibody-mediated internalization of HIV-1 virions depends on antibody specificity and isotype. Evaluation of the phagocytic potency of vaccine

  2. New approaches to design HIV-1 T-cell vaccines.

    Science.gov (United States)

    Perrin, Hélène; Canderan, Glenda; Sékaly, Rafick-Pierre; Trautmann, Lydie

    2010-09-01

    Following the evidence that T-cell responses are crucial in the control of HIV-1 infection, vaccines targeting T-cell responses were tested in recent clinical trials. However, these vaccines showed a lack of efficacy. This review attempts to define the qualitative and quantitative features that are desirable for T-cell-induced responses by vaccines. We also describe strategies that could lead to achievement of this goal. Using the yellow fever vaccine as a benchmark of an efficient vaccine, recent studies identified factors of immune protection and more importantly innate immune pathways needed for the establishment of long-term protective adaptive immunity. To prevent or control HIV-1 infection, a vaccine must induce efficient and persistent antigen-specific T cells endowed with mucosal homing capacity. Such cells should have the capability to counteract HIV-1 diversity and its rapid spread from the initial site of infection. To achieve this goal, the activation of a diversified innate immune response is critical. New systems biology approaches will provide more precise correlates of immune protection that will pave the way for new approaches in T-cell-based vaccines.

  3. 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

  4. 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.

  5. 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

  6. Lack of mutational hot spots during decitabine-mediated HIV-1 mutagenesis.

    Science.gov (United States)

    Rawson, Jonathan M O; Landman, Sean R; Reilly, Cavan S; Bonnac, Laurent; Patterson, Steven E; Mansky, Louis M

    2015-11-01

    Decitabine has previously been shown to induce lethal mutagenesis of human immunodeficiency virus type 1 (HIV-1). However, the factors that determine the susceptibilities of individual sequence positions in HIV-1 to decitabine have not yet been defined. To investigate this, we performed Illumina high-throughput sequencing of multiple amplicons prepared from proviral DNA that was recovered from decitabine-treated cells infected with HIV-1. We found that decitabine induced an ≈4.1-fold increase in the total mutation frequency of HIV-1, primarily due to a striking ≈155-fold increase in the G-to-C transversion frequency. Intriguingly, decitabine also led to an ≈29-fold increase in the C-to-G transversion frequency. G-to-C frequencies varied substantially (up to ≈80-fold) depending upon sequence position, but surprisingly, mutational hot spots (defined as upper outliers within the mutation frequency distribution) were not observed. We further found that every single guanine position examined was significantly susceptible to the mutagenic effects of decitabine. Taken together, these observations demonstrate for the first time that decitabine-mediated HIV-1 mutagenesis is promiscuous and occurs in the absence of a clear bias for mutational hot spots. These data imply that decitabine-mediated G-to-C mutagenesis is a highly effective antiviral mechanism for extinguishing HIV-1 infectivity. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  7. Discordant CSF/plasma HIV-1 RNA in individuals on virologically suppressive antiretroviral therapy in Western India.

    Science.gov (United States)

    Dravid, Ameet N; Natrajan, Kartik; Kulkarni, Milind M; Saraf, Chinmay K; Mahajan, Uma S; Kore, Sachin D; Rathod, Niranjan M; Mahajan, Umakant S; Wadia, Rustom S

    2018-02-01

    Aim of this study was to estimate the prevalence of cerebrospinal fluid (CSF)/Plasma HIV-1 RNA discordance in virologically suppressed individuals presenting with incident neurologic symptoms.In this retrospective cohort study conducted between March 1, 2009, and March 1, 2017, HIV-1 infected adults exposed to atleast 12 months of antiretroviral therapy (ART) and having plasma viral load (VL) CSF/Plasma HIV-1 RNA discordance by measuring HIV-1 RNA in collected plasma and CSF samples. CSF/plasma HIV-1 RNA discordance was defined as either detectable CSF HIV-1 RNA (VL > 20 copies/mL) with an undetectable plasma RNA (complete viral suppression, VL ≤20 copies/mL) or CSF HIV-1 RNA ≥ 0.5 log10 higher than plasma RNA when plasma VL was between 20 and 1000 copies/mL (low-level viremia, LLV).Out of 1584 virologically suppressed patients, 71 (4.4%) presented with incident neurologic symptoms. Twenty out of 71 (28.2%) patients were diagnosed with CSF/Plasma HIV-1 discordance. Median plasma and CSF VL in patients with discordance was 120 [interquartile range (IQR): CSF HIV-1 genotypic resistance testing was done showed mutations that would compromise efficacy of prescribed ART regimen. Prevalence of CSF/plasma HIV-1 RNA discordance was higher among neurologically symptomatic patients with plasma LLV as compared with those with complete viral suppression (70% vs 11.8%, P CSF/plasma HIV-1 RNA discordance indicates replication of HIV-1 that has adapted to the CNS or has developed antiretroviral drug resistance. Larger studies should be performed to study incidence of discordance in India. This will help in managing patients presenting with neurologic symptoms on suppressive ART with appropriate neuroeffective therapy.

  8. Residues in the membrane-spanning domain core modulate conformation and fusogenicity of the HIV-1 envelope glycoprotein

    International Nuclear Information System (INIS)

    Shang Liang; Hunter, Eric

    2010-01-01

    The membrane-spanning domain (MSD) of human immunodeficiency virus type I (HIV-1) envelope glycoprotein (Env) is critical for its biological activity. Initial studies have defined an almost invariant 'core' structure in the MSD and demonstrated that it is crucial for anchoring Env in the membrane and virus entry. We show here that amino acid substitutions in the MSD 'core' do not influence specific virus-cell attachment, nor CD4 receptor and CXCR4 coreceptor recognition by Env. However, substitutions within the MSD 'core' delayed the kinetics and reduced the efficiency of cell-cell fusion mediated by Env. Although we observed no evidence that membrane fusion mediated by the MSD core mutants was arrested at a hemifusion stage, impaired Env fusogenicity was correlated with minor conformational changes in the V2, C1, and C5 regions in gp120 and the immunodominant loop in gp41. These changes could delay initiation of the conformational changes required in the fusion process.

  9. 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.

  10. MAS NMR of HIV-1 protein assemblies

    Science.gov (United States)

    Suiter, Christopher L.; Quinn, Caitlin M.; Lu, Manman; Hou, Guangjin; Zhang, Huilan; Polenova, Tatyana

    2015-04-01

    The negative global impact of the AIDS pandemic is well known. In this perspective article, the utility of magic angle spinning (MAS) NMR spectroscopy to answer pressing questions related to the structure and dynamics of HIV-1 protein assemblies is examined. In recent years, MAS NMR has undergone major technological developments enabling studies of large viral assemblies. We discuss some of these evolving methods and technologies and provide a perspective on the current state of MAS NMR as applied to the investigations into structure and dynamics of HIV-1 assemblies of CA capsid protein and of Gag maturation intermediates.

  11. Tetherin restricts productive HIV-1 cell-to-cell transmission.

    Directory of Open Access Journals (Sweden)

    Nicoletta Casartelli

    2010-06-01

    Full Text Available The IFN-inducible antiviral protein tetherin (or BST-2/CD317/HM1.24 impairs release of mature HIV-1 particles from infected cells. HIV-1 Vpu antagonizes the effect of tetherin. The fate of virions trapped at the cell surface remains poorly understood. Here, we asked whether tetherin impairs HIV cell-to-cell transmission, a major means of viral spread. Tetherin-positive or -negative cells, infected with wild-type or DeltaVpu HIV, were used as donor cells and cocultivated with target lymphocytes. We show that tetherin inhibits productive cell-to-cell transmission of DeltaVpu to targets and impairs that of WT HIV. Tetherin accumulates with Gag at the contact zone between infected and target cells, but does not prevent the formation of virological synapses. In the presence of tetherin, viruses are then mostly transferred to targets as abnormally large patches. These viral aggregates do not efficiently promote infection after transfer, because they accumulate at the surface of target cells and are impaired in their fusion capacities. Tetherin, by imprinting virions in donor cells, is the first example of a surface restriction factor limiting viral cell-to-cell spread.

  12. 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

  13. Chimeric peptide-mediated siRNA transduction to inhibit HIV-1 infection.

    Science.gov (United States)

    Bivalkar-Mehla, Shalmali; Mehla, Rajeev; Chauhan, Ashok

    2017-04-01

    Persistent human immunodeficiency virus 1 (HIV-1) infection provokes immune activation and depletes CD4 +  lymphocytes, leading to acquired immunodeficiency syndrome. Uninterrupted administration of combination antiretroviral therapy (cART) in HIV-infected patients suppresses viral replication to below the detectable level and partially restores the immune system. However, cART-unresponsive residual HIV-1 infection and elusive transcriptionally silent but reactivatable viral reservoirs maintain a permanent viral DNA blue print. The virus rebounds within a few weeks after interruption of suppressive therapy. Adjunct gene therapy to control viral replication by ribonucleic acid interference (RNAi) is a post-transcriptional gene silencing strategy that could suppress residual HIV-1 burden and overcome viral resistance. Small interfering ribonucleic acids (siRNAs) are efficient transcriptional inhibitors, but need delivery systems to reach inside target cells. We investigated the potential of chimeric peptide (FP-PTD) to deliver specific siRNAs to HIV-1-susceptible and permissive cells. Chimeric FP-PTD peptide was designed with an RNA binding domain (PTD) to bind siRNA and a cell fusion peptide domain (FP) to enter cells. FP-PTD-siRNA complex entered and inhibited HIV-1 replication in susceptible cells, and could be a candidate for in vivo testing.

  14. Identification of a D-amino acid decapeptide HIV-1 entry inhibitor

    International Nuclear Information System (INIS)

    Boggiano, Cesar; Jiang Shibo; Lu Hong; Zhao Qian; Liu Shuwen; Binley, James; Blondelle, Sylvie E.

    2006-01-01

    Entry of human immunodeficiency virus type 1 (HIV-1) virion into host cells involves three major steps, each being a potential target for the development of entry inhibitors: gp120 binding to CD4, gp120-CD4 complex interacting with a coreceptor, and gp41 refolding to form a six-helix bundle. Using a D-amino acid decapeptide combinatorial library, we identified peptide DC13 as having potent HIV-1 fusion inhibitory activity, and effectively inhibiting infection by several laboratory-adapted and primary HIV-1 strains. While DC13 did not block binding of gp120 to CD4, nor disrupt the gp41 six-helix bundle formation, it effectively blocked the binding of an anti-CXCR4 monoclonal antibody and chemokine SDF-1α to CXCR4-expressing cells. However, because R5-using primary viruses were also neutralized, the antiviral activity of DC13 implies additional mode(s) of action. These results suggest that DC13 is a useful HIV-1 coreceptor antagonist for CXCR4 and, due to its biostability and simplicity, may be of value for developing a new class of HIV-1 entry inhibitors

  15. 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 ...

  16. Epidemiology of HIV-1 and emerging problems

    NARCIS (Netherlands)

    Lukashov, V. V.; de Ronde, A.; de Jong, J. J.; Goudsmit, J.

    2000-01-01

    Broad use of antiretroviral drugs is becoming a factor that is important to consider for understanding the HIV-1 epidemiology. Since 1993, we observe that a proportion of new infections within major risk groups in Amsterdam is caused by azidothymidine (AZT)-resistant viruses. After the introduction

  17. Multivalent dendrimeric compounds containing carbohydrates expressed on immune cells inhibit infection by primary isolates of HIV-1

    International Nuclear Information System (INIS)

    Rosa Borges, Andrew; Wieczorek, Lindsay; Johnson, Benitra; Benesi, Alan J.; Brown, Bruce K.; Kensinger, Richard D.; Krebs, Fred C.; Wigdahl, Brian; Blumenthal, Robert; Puri, Anu; McCutchan, Francine E.; Birx, Deborah L.; Polonis, Victoria R.; Schengrund, Cara-Lynne

    2010-01-01

    Specific glycosphingolipids (GSL), found on the surface of target immune cells, are recognized as alternate cell surface receptors by the human immunodeficiency virus type 1 (HIV-1) external envelope glycoprotein. In this study, the globotriose and 3'-sialyllactose carbohydrate head groups found on two GSL were covalently attached to a dendrimer core to produce two types of unique multivalent carbohydrates (MVC). These MVC inhibited HIV-1 infection of T cell lines and primary peripheral blood mononuclear cells (PBMC) by T cell line-adapted viruses or primary isolates, with IC 50 s ranging from 0.1 to 7.4 μg/ml. Inhibition of Env-mediated membrane fusion by MVC was also observed using a dye-transfer assay. These carbohydrate compounds warrant further investigation as a potential new class of HIV-1 entry inhibitors. The data presented also shed light on the role of carbohydrate moieties in HIV-1 virus-host cell interactions. -- Research Highlights: →Multivalent carbohydrates (MVCs) inhibited infection of PBMCs by HIV-1. →MVCs inhibited infection by T cell line-adapted viruses. →MVCs inhibited infection by primary isolates of HIV-1. →MVCs inhibited Env-mediated membrane fusion.

  18. 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.

  19. Multivalent dendrimeric compounds containing carbohydrates expressed on immune cells inhibit infection by primary isolates of HIV-1

    Science.gov (United States)

    Borges, Andrew Rosa; Wieczorek, Lindsay; Johnson, Benitra; Benesi, Alan J.; Brown, Bruce K.; Kensinger, Richard D.; Krebs, Fred C.; Wigdahl, Brian; Blumenthal, Robert; Puri, Anu; McCutchan, Francine E.; Birx, Deborah L.; Polonis, Victoria R.; Schengrund, Cara-Lynne

    2010-01-01

    Specific glycosphingolipids (GSL), found on the surface of target immune cells, are recognized as alternate cell surface receptors by the human immunodeficiency virus type 1 (HIV-1) external envelope glycoprotein. In this study, the globotriose and 3’-sialyllactose carbohydrate head groups found on two GSL were covalently attached to a dendrimer core to produce two types of unique multivalent carbohydrates (MVC). These MVC inhibited HIV-1 infection of T cell lines and primary peripheral blood mononuclear cells (PBMC) by T cell line-adapted viruses or primary isolates, with IC50s ranging from 0.1 – 7.4 µg/ml. Inhibition of Env-mediated membrane fusion by MVC was also observed using a dye-transfer assay. These carbohydrate compounds warrant further investigation as a potential new class of HIV-1 entry inhibitors. The data presented also shed light on the role of carbohydrate moieties in HIV-1 virus-host cell interactions. PMID:20880566

  20. Requirements for capsid-binding and an effector function in TRIMCyp-mediated restriction of HIV-1

    International Nuclear Information System (INIS)

    Diaz-Griffero, Felipe; Vandegraaff, Nick; Li Yuan; McGee-Estrada, Kathleen; Stremlau, Matthew; Welikala, Sohanya; Si Zhihai; Engelman, Alan; Sodroski, Joseph

    2006-01-01

    In owl monkeys, a retrotransposition event replaced the gene encoding the retroviral restriction factor TRIM5α with one encoding TRIMCyp, a fusion between the RING, B-box 2 and coiled-coil domains of TRIM5 and cyclophilin A. TRIMCyp restricts human immunodeficiency virus (HIV-1) infection by a mechanism dependent on the interaction of the cyclophilin A moiety and the HIV-1 capsid protein. Here, we show that infection by retroviruses other than HIV-1 can be restricted by TRIMCyp, providing an explanation for the evolutionary retention of the TRIMCyp gene in owl monkey lineages. The TRIMCyp-mediated block to HIV-1 infection occurs before the earliest step of reverse transcription. TRIMCyp-mediated restriction involves at least two functions: (1) capsid binding, which occurs most efficiently for trimeric TRIMCyp proteins that retain the coiled-coil and cyclophilin A domains, and (2) an effector function that depends upon the B-box 2 domain

  1. Astrocytes sustain long-term productive HIV-1 infection without establishment of reactivable viral latency.

    Science.gov (United States)

    Barat, Corinne; Proust, Alizé; Deshiere, Alexandre; Leboeuf, Mathieu; Drouin, Jean; Tremblay, Michel J

    2018-02-21

    The "shock and kill" HIV-1 cure strategy proposes eradication of stable cellular reservoirs by clinical treatment with latency-reversing agents (LRAs). Although resting CD4 + T cells latently infected with HIV-1 constitute the main reservoir that is targeted by these approaches, their consequences on other reservoirs such as the central nervous system are still unknown and should be taken into consideration. We performed experiments aimed at defining the possible role of astrocytes in HIV-1 persistence in the brain and the effect of LRA treatments on this viral sanctuary. We first demonstrate that the diminished HIV-1 production in a proliferating astrocyte culture is due to a reduced proliferative capacity of virus-infected cells compared with uninfected astrocytes. In contrast, infection of non-proliferating astrocytes led to a robust HIV-1 infection that was sustained for over 60 days. To identify astrocytes latently infected with HIV-1, we designed a new dual-color reporter virus called NL4.3 eGFP-IRES-Crimson that is fully infectious and encodes for all viral proteins. Although we detected a small fraction of astrocytes carrying silent HIV-1 proviruses, we did not observe any reactivation using various LRAs and even strong inducers such as tumor necrosis factor, thus suggesting that these proviruses were either not transcriptionally competent or in a state of deep latency. Our findings imply that astrocytes might not constitute a latent reservoir per se but that relentless virus production by this brain cell population could contribute to the neurological disorders seen in HIV-1-infected persons subjected to combination antiretroviral therapy. © 2018 Wiley Periodicals, Inc.

  2. Regulatory T cells expanded from HIV-1-infected individuals maintain phenotype, TCR repertoire and suppressive capacity.

    Directory of Open Access Journals (Sweden)

    Mathieu Angin

    Full Text Available While modulation of regulatory T cell (Treg function and adoptive Treg transfer are being explored as therapeutic modalities in the context of autoimmune diseases, transplantation and cancer, their role in HIV-1 pathogenesis remains less well defined. Controversy persists regarding their beneficial or detrimental effects in HIV-1 disease, which warrants further detailed exploration. Our objectives were to investigate if functional CD4(+ Tregs can be isolated and expanded from HIV-1-infected individuals for experimental or potential future therapeutic use and to determine phenotype and suppressive capacity of expanded Tregs from HIV-1 positive blood and tissue. Tregs and conventional T cell controls were isolated from blood and gut-associated lymphoid tissue of individuals with HIV-1 infection and healthy donors using flow-based cell-sorting. The phenotype of expanded Tregs was assessed by flow-cytometry and quantitative PCR. T-cell receptor ß-chain (TCR-β repertoire diversity was investigated by deep sequencing. Flow-based T-cell proliferation and chromium release cytotoxicity assays were used to determine Treg suppressive function. Tregs from HIV-1 positive individuals, including infants, were successfully expanded from PBMC and GALT. Expanded Tregs expressed high levels of FOXP3, CTLA4, CD39 and HELIOS and exhibited a highly demethylated TSDR (Treg-specific demethylated region, characteristic of Treg lineage. The TCRß repertoire was maintained following Treg expansion and expanded Tregs remained highly suppressive in vitro. Our data demonstrate that Tregs can be expanded from blood and tissue compartments of HIV-1+ donors with preservation of Treg phenotype, function and TCR repertoire. These results are highly relevant for the investigation of potential future therapeutic use, as currently investigated for other disease states and hold great promise for detailed studies on the role of Tregs in HIV-1 infection.

  3. 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.

  4. 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

  5. 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.

  6. Super-resolution imaging of ESCRT-proteins at HIV-1 assembly sites.

    Directory of Open Access Journals (Sweden)

    Jens Prescher

    2015-02-01

    Full Text Available The cellular endosomal sorting complex required for transport (ESCRT machinery is involved in membrane budding processes, such as multivesicular biogenesis and cytokinesis. In HIV-infected cells, HIV-1 hijacks the ESCRT machinery to drive HIV release. Early in the HIV-1 assembly process, the ESCRT-I protein Tsg101 and the ESCRT-related protein ALIX are recruited to the assembly site. Further downstream, components such as the ESCRT-III proteins CHMP4 and CHMP2 form transient membrane associated lattices, which are involved in virus-host membrane fission. Although various geometries of ESCRT-III assemblies could be observed, the actual membrane constriction and fission mechanism is not fully understood. Fission might be driven from inside the HIV-1 budding neck by narrowing the membranes from the outside by larger lattices surrounding the neck, or from within the bud. Here, we use super-resolution fluorescence microscopy to elucidate the size and structure of the ESCRT components Tsg101, ALIX, CHMP4B and CHMP2A during HIV-1 budding below the diffraction limit. To avoid the deleterious effects of using fusion proteins attached to ESCRT components, we performed measurements on the endogenous protein or, in the case of CHMP4B, constructs modified with the small HA tag. Due to the transient nature of the ESCRT interactions, the fraction of HIV-1 assembly sites with colocalizing ESCRT complexes was low (1.5%-3.4%. All colocalizing ESCRT clusters exhibited closed, circular structures with an average size (full-width at half-maximum between 45 and 60 nm or a diameter (determined using a Ripley's L-function analysis of roughly 60 to 100 nm. The size distributions for colocalizing clusters were narrower than for non-colocalizing clusters, and significantly smaller than the HIV-1 bud. Hence, our results support a membrane scission process driven by ESCRT protein assemblies inside a confined structure, such as the bud neck, rather than by large lattices

  7. 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

  8. 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.

  9. Morphogenesis of the infectious HIV-1 virion

    Directory of Open Access Journals (Sweden)

    Jun-Ichi eSakuragi

    2011-12-01

    Full Text Available The virion of HIV-1 is spherical and viral glycoprotein spikes (gp120, gp41 protrude from its envelope. The characteristic cone-shaped core exists within the virion, caging the ribonucleoprotein (RNP complex, which is comprised of viral RNA, nucleocapsid (NC and viral enzymes. The HIV-1 virion is budded and released from the infected cell as an immature donut-shaped particle. During or immediately after release, viral protease (PR is activated and subsequently processes the viral structural protein Gag. Through this maturation process, virions acquire infectivity, but its mechanism and transition of morphology largely remain unclear. Recent technological advances in experimental devices and techniques have made it possible to closely dissect the viral production site on the cell, the exterior – or even the interior – of an individual virion, and many new aspects on virion morphology and maturation. In this manuscript, I review the morphogenesis of HIV-1 virions. I focus on several studies, including some of our recent findings, which examined virion formation and/or maturation processes. The story of novel compound, which inhibits virion maturation, and the importance of maturation research are also discussed.

  10. HIV-1 Eradication Strategies: Design and Assessment

    Science.gov (United States)

    Siliciano, Robert F.

    2014-01-01

    Purpose of review Recent developments have generated renewed interest in the possibility of curing HIV-1 infection. This review describes some of the practical challenges that will need to be overcome if curative strategies are to be successful. Recent findings The latent reservoir for HIV-1 in resting memory CD4+ T cells is the major barrier to curing the infection. The most widely discussed approach to curing the infection involves finding agents that reverse latency in resting CD4+ T cells, with the assumption that the cells will then die from viral cytopathic effects or be lysed by host cytolytic T lymphocytes (CTL). A major challenge is the development of in vitro models that can be used to explore mechanisms and identify latency reversing agents (LRA). Although several models have been developed, including primary cell models, none of them may fully capture the quiescent state of the cells that harbor latent HIV-1 in vivo. An additional problem is that LRA that do not cause T cell activation may not lead to the death of infected cells. Finally, measuring the effects of LRAs in vivo is complicated by the lack of correlation between different assays for the latent reservoir. Summary Progress on these practical issues is essential to finding a cure. PMID:23698561

  11. 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

  12. 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.

  13. 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.

  14. 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.

  15. A national study of the molecular epidemiology of HIV-1 in Australia 2005–2012

    Science.gov (United States)

    Castley, Alison; Sawleshwarkar, Shailendra; Varma, Rick; Herring, Belinda; Thapa, Kiran; Dwyer, Dominic; Chibo, Doris; Nguyen, Nam; Hawke, Karen; Ratcliff, Rodney; Garsia, Roger; Kelleher, Anthony; Nolan, David

    2017-01-01

    Introduction Rates of new HIV-1 diagnoses are increasing in Australia, with evidence of an increasing proportion of non-B HIV-1 subtypes reflecting a growing impact of migration and travel. The present study aims to define HIV-1 subtype diversity patterns and investigate possible HIV-1 transmission networks within Australia. Methods The Australian Molecular Epidemiology Network (AMEN) HIV collaborating sites in Western Australia, South Australia, Victoria, Queensland and western Sydney (New South Wales), provided baseline HIV-1 partial pol sequence, age and gender information for 4,873 patients who had genotypes performed during 2005–2012. HIV-1 phylogenetic analyses utilised MEGA V6, with a stringent classification of transmission pairs or clusters (bootstrap ≥98%, genetic distance ≤1.5% from at least one other sequence in the cluster). Results HIV-1 subtype B represented 74.5% of the 4,873 sequences (WA 59%, SA 68.4%, w-Syd 73.8%, Vic 75.6%, Qld 82.1%), with similar proportion of transmission pairs and clusters found in the B and non-B cohorts (23% vs 24.5% of sequences, p = 0.3). Significantly more subtype B clusters were comprised of ≥3 sequences compared with non-B clusters (45.0% vs 24.0%, p = 0.021) and significantly more subtype B pairs and clusters were male-only (88% compared to 53% CRF01_AE and 17% subtype C clusters). Factors associated with being in a cluster of any size included; being sequenced in a more recent time period (p3) was associated with being sequenced in a more recent time period (p = 0.05) and being male (p = 0.008). Conclusion This nationwide HIV-1 study of 4,873 patient sequences highlights the increased diversity of HIV-1 subtypes within the Australian epidemic, as well as differences in transmission networks associated with these HIV-1 subtypes. These findings provide epidemiological insights not readily available using standard surveillance methods and can inform the development of effective public health strategies in the

  16. A national study of the molecular epidemiology of HIV-1 in Australia 2005-2012.

    Directory of Open Access Journals (Sweden)

    Alison Castley

    Full Text Available Rates of new HIV-1 diagnoses are increasing in Australia, with evidence of an increasing proportion of non-B HIV-1 subtypes reflecting a growing impact of migration and travel. The present study aims to define HIV-1 subtype diversity patterns and investigate possible HIV-1 transmission networks within Australia.The Australian Molecular Epidemiology Network (AMEN HIV collaborating sites in Western Australia, South Australia, Victoria, Queensland and western Sydney (New South Wales, provided baseline HIV-1 partial pol sequence, age and gender information for 4,873 patients who had genotypes performed during 2005-2012. HIV-1 phylogenetic analyses utilised MEGA V6, with a stringent classification of transmission pairs or clusters (bootstrap ≥98%, genetic distance ≤1.5% from at least one other sequence in the cluster.HIV-1 subtype B represented 74.5% of the 4,873 sequences (WA 59%, SA 68.4%, w-Syd 73.8%, Vic 75.6%, Qld 82.1%, with similar proportion of transmission pairs and clusters found in the B and non-B cohorts (23% vs 24.5% of sequences, p = 0.3. Significantly more subtype B clusters were comprised of ≥3 sequences compared with non-B clusters (45.0% vs 24.0%, p = 0.021 and significantly more subtype B pairs and clusters were male-only (88% compared to 53% CRF01_AE and 17% subtype C clusters. Factors associated with being in a cluster of any size included; being sequenced in a more recent time period (p3 was associated with being sequenced in a more recent time period (p = 0.05 and being male (p = 0.008.This nationwide HIV-1 study of 4,873 patient sequences highlights the increased diversity of HIV-1 subtypes within the Australian epidemic, as well as differences in transmission networks associated with these HIV-1 subtypes. These findings provide epidemiological insights not readily available using standard surveillance methods and can inform the development of effective public health strategies in the current paradigm of HIV prevention

  17. A national study of the molecular epidemiology of HIV-1 in Australia 2005-2012.

    Science.gov (United States)

    Castley, Alison; Sawleshwarkar, Shailendra; Varma, Rick; Herring, Belinda; Thapa, Kiran; Dwyer, Dominic; Chibo, Doris; Nguyen, Nam; Hawke, Karen; Ratcliff, Rodney; Garsia, Roger; Kelleher, Anthony; Nolan, David

    2017-01-01

    Rates of new HIV-1 diagnoses are increasing in Australia, with evidence of an increasing proportion of non-B HIV-1 subtypes reflecting a growing impact of migration and travel. The present study aims to define HIV-1 subtype diversity patterns and investigate possible HIV-1 transmission networks within Australia. The Australian Molecular Epidemiology Network (AMEN) HIV collaborating sites in Western Australia, South Australia, Victoria, Queensland and western Sydney (New South Wales), provided baseline HIV-1 partial pol sequence, age and gender information for 4,873 patients who had genotypes performed during 2005-2012. HIV-1 phylogenetic analyses utilised MEGA V6, with a stringent classification of transmission pairs or clusters (bootstrap ≥98%, genetic distance ≤1.5% from at least one other sequence in the cluster). HIV-1 subtype B represented 74.5% of the 4,873 sequences (WA 59%, SA 68.4%, w-Syd 73.8%, Vic 75.6%, Qld 82.1%), with similar proportion of transmission pairs and clusters found in the B and non-B cohorts (23% vs 24.5% of sequences, p = 0.3). Significantly more subtype B clusters were comprised of ≥3 sequences compared with non-B clusters (45.0% vs 24.0%, p = 0.021) and significantly more subtype B pairs and clusters were male-only (88% compared to 53% CRF01_AE and 17% subtype C clusters). Factors associated with being in a cluster of any size included; being sequenced in a more recent time period (p3) was associated with being sequenced in a more recent time period (p = 0.05) and being male (p = 0.008). This nationwide HIV-1 study of 4,873 patient sequences highlights the increased diversity of HIV-1 subtypes within the Australian epidemic, as well as differences in transmission networks associated with these HIV-1 subtypes. These findings provide epidemiological insights not readily available using standard surveillance methods and can inform the development of effective public health strategies in the current paradigm of HIV prevention in

  18. Lack of integrase inhibitors associated resistance mutations among HIV-1C isolates.

    Science.gov (United States)

    Mulu, Andargachew; Maier, Melanie; Liebert, Uwe Gerd

    2015-12-01

    Although biochemical analysis of HIV-1 integrase enzyme suggested the use of integrase inhibitors (INIs) against HIV-1C, different viral subtypes may favor different mutational pathways potentially leading to varying levels of drug resistance. Thus, the aim of this study was to search for the occurrence and natural evolution of integrase polymorphisms and/or resistance mutations in HIV-1C Ethiopian clinical isolates prior to the introduction of INIs. Plasma samples from chronically infected drug naïve patients (N = 45), of whom the PR and RT sequence was determined previously, were used to generate population based sequences of HIV-1 integrase. HIV-1 subtype was determined using the REGA HIV-1 subtyping tool. Resistance mutations were interpreted according to the Stanford HIV drug resistance database ( http://hivdb.stanford.edu ) and the updated International Antiviral Society (IAS)-USA mutation lists. Moreover, rates of polymorphisms in the current isolates were compared with South African and global HIV-1C isolates. All subjects were infected with HIV-1C concordant to the protease (PR) and reverse transcriptase (RT) regions. Neither major resistance-associated IN mutations (T66I/A/K, E92Q/G, T97A, Y143HCR, S147G, Q148H/R/K, and N155H) nor silent mutations known to change the genetic barrier were observed. Moreover, the DDE-catalytic motif (D64G/D116G/E152 K) and signature HHCC zinc-binding motifs at codon 12, 16, 40 and 43 were found to be highly conserved. However, compared to other South African subtype C isolates, the rate of polymorphism was variable at various positions. Although the sample size is small, the findings suggest that this drug class could be effective in Ethiopia and other southern African countries where HIV-1C is predominantly circulating. The data will contribute to define the importance of integrase polymorphism and to improve resistance interpretation algorithms in HIV-1C isolates.

  19. Developing a Dynamic Pharmacophore Model for HIV-1 Integrase

    International Nuclear Information System (INIS)

    Carlson, Heather A.; Masukawa, Keven M.; Rubins, Kathleen; Bushman, Frederic; Jorgensen, William L.; Lins, Roberto; Briggs, James; Mccammon, Andy

    2000-01-01

    We present the first receptor-based pharmacophore model for HIV-1 integrase. The development of ''dynamic'' pharmacophore models is a new method that accounts for the inherent flexibility of the active site and aims to reduce the entropic penalties associated with binding a ligand. Furthermore, this new drug discovery method overcomes the limitation of an incomplete crystal structure of the target protein. A molecular dynamics (MD) simulation describes the flexibility of the uncomplexed protein. Many conformational models of the protein are saved from the MD simulations and used in a series of multi-unit search for interacting conformers (MUSIC) simulations. MUSIC is a multiple-copy minimization method, available in the BOSS program; it is used to determine binding regions for probe molecules containing functional groups that complement the active site. All protein conformations from the MD are overlaid, and conserved binding regions for the probe molecules are identified. Those conserved binding regions define the dynamic pharmacophore model. Here, the dynamic model is compared to known inhibitors of the integrase as well as a three-point, ligand-based pharmacophore model from the literature. Also, a ''static'' pharmacophore model was determined in the standard fashion, using a single crystal structure. Inhibitors thought to bind in the active site of HIV-1 integrase fit the dynamic model but not the static model. Finally, we have identified a set of compounds from the Available Chemicals Directory that fit the dynamic pharmacophore model, and experimental testing of the compounds has confirmed several new inhibitors

  20. HIV-1 infection: the role of the gastrointestinal tract.

    Science.gov (United States)

    Cavarelli, Mariangela; Scarlatti, Gabriella

    2014-06-01

    The intestinal mucosa has an important role as portal of entry during mother-to-child transmission of HIV-1 and during sexual transmission. Tissue morphology and integrity, as well as distribution of relevant cell types within the mucosa, spanning from the oropharynx to the rectum, can greatly influence viral infection, replication, presentation, and persistence. The relative contribution to transmission by cell-associated or cell-free virus is still not defined for the different routes of transmission. Although the main target cells for HIV-1 replication are the CD4+ T lymphocytes, which are rapidly depleted both in the periphery and in the mucosal tissues, dendritic cells, Langerhans' cells, and macrophages are players in each of these processes. The predominant cells involved may differ according to the tract of the gut and the route of transmission. The microenvironment of the intestinal mucosa, including mucus, antibodies, or chemo-cytokines, can as well influence infection and replication of the virus: their role is still under investigation. The understanding of these processes may help in developing efficient prevention strategies. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  1. Improved intracellular delivery of glucocerebrosidase mediated by the HIV-1 TAT protein transduction domain

    International Nuclear Information System (INIS)

    Lee, Kyun Oh; Luu, Nga; Kaneski, Christine R.; Schiffmann, Raphael; Brady, Roscoe O.; Murray, Gary J.

    2005-01-01

    Enzyme replacement therapy (ERT) for Gaucher disease designed to target glucocerebrosidase (GC) to macrophages via mannose-specific endocytosis is very effective in reversing hepatosplenomegaly, and normalizing hematologic parameters but is less effective in improving bone and lung involvement and ineffective in brain. Recombinant GCs containing an in-frame fusion to the HIV-1 trans-activator protein transduction domain (TAT) were expressed in eukaryotic cells in order to obtain active, normally glycosylated GC fusion proteins for enzyme uptake studies. Despite the absence of mannose-specific endocytic receptors on the plasma membranes of various fibroblasts, the recombinant GCs with C-terminal TAT fusions were readily internalized by these cells. Immunofluorescent confocal microscopy demonstrated the recombinant TAT-fusion proteins with a mixed endosomal and lysosomal localization. Thus, TAT-modified GCs represent a novel strategy for a new generation of therapeutic enzymes for ERT for Gaucher disease

  2. 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.

  3. Cloaked similarity between HIV-1 and SARS-CoV suggests an anti-SARS strategy

    Directory of Open Access Journals (Sweden)

    Kliger Yossef

    2003-09-01

    Full Text Available Abstract Background Severe acute respiratory syndrome (SARS is a febrile respiratory illness. The disease has been etiologically linked to a novel coronavirus that has been named the SARS-associated coronavirus (SARS-CoV, whose genome was recently sequenced. Since it is a member of the Coronaviridae, its spike protein (S2 is believed to play a central role in viral entry by facilitating fusion between the viral and host cell membranes. The protein responsible for viral-induced membrane fusion of HIV-1 (gp41 differs in length, and has no sequence homology with S2. Results Sequence analysis reveals that the two viral proteins share the sequence motifs that construct their active conformation. These include (1 an N-terminal leucine/isoleucine zipper-like sequence, and (2 a C-terminal heptad repeat located upstream of (3 an aromatic residue-rich region juxtaposed to the (4 transmembrane segment. Conclusions This study points to a similar mode of action for the two viral proteins, suggesting that anti-viral strategy that targets the viral-induced membrane fusion step can be adopted from HIV-1 to SARS-CoV. Recently the FDA approved Enfuvirtide, a synthetic peptide corresponding to the C-terminal heptad repeat of HIV-1 gp41, as an anti-AIDS agent. Enfuvirtide and C34, another anti HIV-1 peptide, exert their inhibitory activity by binding to a leucine/isoleucine zipper-like sequence in gp41, thus inhibiting a conformational change of gp41 required for its activation. We suggest that peptides corresponding to the C-terminal heptad repeat of the S2 protein may serve as inhibitors for SARS-CoV entry.

  4. 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

  5. CD4- and dynamin-dependent endocytosis of HIV-1 into plasmacytoid dendritic cells

    Energy Technology Data Exchange (ETDEWEB)

    Pritschet, Kathrin; Donhauser, Norbert; Schuster, Philipp; Ries, Moritz; Haupt, Sabrina; Kittan, Nicolai A.; Korn, Klaus [Institute of Clinical and Molecular Virology, National Reference Centre for Retroviruses, Friedrich-Alexander-Universitaet Erlangen-Nuernberg, 91054 Erlangen (Germany); Poehlmann, Stefan [Institute of Virology, Hannover Medical School, 30625 Hannover (Germany); Holland, Gudrun; Bannert, Norbert [Robert Koch-Institute, Center for Biological Security 4, 13353 Berlin (Germany); Bogner, Elke [Institute of Virology, Charite University Hospital, 10117 Berlin (Germany); Schmidt, Barbara, E-mail: baschmid@viro.med.uni-erlangen.de [Institute of Clinical and Molecular Virology, National Reference Centre for Retroviruses, Friedrich-Alexander-Universitaet Erlangen-Nuernberg, 91054 Erlangen (Germany)

    2012-02-20

    Chronic immune activation, triggered by plasmacytoid dendritic cell (PDC) interferon (IFN)-alpha production, plays an important role in HIV-1 pathogenesis. As the entry of HIV-1 seems to be important for the activation of PDC, we directly characterized the viral entry into these cells using immuno-electron microscopy, cellular fractionation, confocal imaging, and functional experiments. After attachment to PDC, viruses were taken up in an energy-dependent manner. The virions were located in compartments positive for caveolin; early endosomal antigen 1; Rab GTPases 5, 7 and 9; lysosomal-associated membrane protein 1. PDC harbored more virus in endocytic vesicles than CD4+ T cells (p < 0.05). Blocking CD4 inhibited the uptake of virions into cytosolic and endosomal compartments. Dynasore, an inhibitor of dynamin-dependent endocytosis, not the fusion inhibitor T-20, reduced the HIV-1 induced IFN-alpha production. Altogether, our morphological and functional data support the role of endocytosis for the entry and IFN-alpha induction of HIV-1 in PDC.

  6. 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.

  7. Validation of an automated system for aliquoting of HIV-1 Env-pseudotyped virus stocks.

    Science.gov (United States)

    Schultz, Anke; Germann, Anja; Fuss, Martina; Sarzotti-Kelsoe, Marcella; Ozaki, Daniel A; Montefiori, David C; Zimmermann, Heiko; von Briesen, Hagen

    2018-01-01

    The standardized assessments of HIV-specific immune responses are of main interest in the preclinical and clinical stage of HIV-1 vaccine development. In this regard, HIV-1 Env-pseudotyped viruses play a central role for the evaluation of neutralizing antibody profiles and are produced according to Good Clinical Laboratory Practice- (GCLP-) compliant manual and automated procedures. To further improve and complete the automated production cycle an automated system for aliquoting HIV-1 pseudovirus stocks has been implemented. The automation platform consists of a modified Tecan-based system including a robot platform for handling racks containing 48 cryovials, a Decapper, a tubing pump and a safety device consisting of ultrasound sensors for online liquid level detection of each individual cryovial. With the aim to aliquot the HIV-1 pseudoviruses in an automated manner under GCLP-compliant conditions a validation plan was developed where the acceptance criteria-accuracy, precision as well as the specificity and robustness-were defined and summarized. By passing the validation experiments described in this article the automated system for aliquoting has been successfully validated. This allows the standardized and operator independent distribution of small-scale and bulk amounts of HIV-1 pseudovirus stocks with a precise and reproducible outcome to support upcoming clinical vaccine trials.

  8. Contribution of immunological and virological factors to extremely severe primary HIV-1 infection

    Science.gov (United States)

    Dalmau, Judith; Puertas, Maria Carmen; Azuara, Marta; Mariño, Ana; Frahm, Nicole; Mothe, Beatriz; Izquierdo-Useros, Nuria; Buzón, Maria José; Paredes, Roger; Matas, Lourdes; Allen, Todd M.; Brander, Christian; Rodrigo, Carlos; Clotet, Bonaventura; Martinez-Picado, Javier

    2009-01-01

    Background During acute HIV infection, high viral loads and the induction of host immune responses typically coincide with the onset of clinical symptoms. However, clinically severe presentations during acute HIV-1 infection, including AIDS-defining symptoms, are unusual. Methods Virus isolates were tested for clade, drug susceptibility, coreceptor usage, and growth rate for two cases of clinically severe sexual transmission. HLA genotype was determined, and HIV-1-specific CTL responses to an overlapping peptide set spanning the entire HIV clade A and clade B proteome were assayed. Results The virus isolated from the two unrelated cases of severe primary HIV-1 infection showed R5/X4 dual/mixed tropism, belonged to clade B and CRF02-AG, and were highly replicative in peripheral blood mononuclear cell culture. Impaired humoral responses were paralleled by a profound absence of HIV-1-specific CTL responses to the entire viral proteome in the two study cases. One case for which the virus source was available, showed a remarkable HLA similarity between the transmission pair as all 4 HLA-A and -B alleles were HLA supertype-matched between the subjects involved in the transmission case. Conclusions The data suggest that concurrence of viral and host factors contribute to the clinical severity of primary HIV-1 infection and that subjects infected with highly replicative dual tropic viruses are more prone to develop AIDS-defining symptoms during acute infection if they are unable to mount humoral and cellular HIV-1-specific immune responses. Concordant HLA supertypes might facilitate the preferential transmission of HLA-adapted viral variants, further accelerating disease progression. PMID:19093810

  9. 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.

  10. 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.

  11. 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.

  12. 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

  13. 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.

  14. 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.

  15. Identification of N-phenyl-N'-(2,2,6,6-tetramethyl-piperidin-4-yl)-oxalamides as a new class of HIV-1 entry inhibitors that prevent gp120 binding to CD4

    International Nuclear Information System (INIS)

    Zhao Qian; Ma Liying; Jiang Shibo; Lu Hong; Liu Shuwen; He Yuxian; Strick, Nathan; Neamati, Nouri; Debnath, Asim Kumar

    2005-01-01

    We have identified two N-phenyl-N'-(2,2,6,6-tetramethyl-piperidin-4-yl)-oxalamide analogs as a novel class of human immunodeficiency virus type 1 (HIV-1) entry inhibitors that block the gp120-CD4 interaction, using database screening techniques. The lead compounds, NBD-556 and NBD-557, are small molecule organic compounds with drug-like properties. These compounds showed potent cell fusion and virus-cell fusion inhibitory activity at low micromolar levels. A systematic study showed that these compounds target viral entry by inhibiting the binding of HIV-1 envelope glycoprotein gp120 to the cellular receptor CD4 but did not inhibit reverse transcriptase, integrase, or protease, indicating that they do not target the later stages of the HIV-1 life cycle to inhibit HIV-1 infection. These compounds were equally potent inhibitors of both X4 and R5 viruses tested in CXCR4 and CCR5 expressing cell lines, respectively, indicating that their anti-HIV-1 activity is not dependent on the coreceptor tropism of the virus. A surface plasmon resonance study, which measures binding affinity, clearly demonstrated that these compounds bind to unliganded HIV-1 gp120 but not to the cellular receptor CD4. NBD-556 and NBD-557 were active against HIV-1 laboratory-adapted strains including an AZT-resistant strain and HIV-1 primary isolates, indicating that these compounds can potentially be further modified to become potent HIV-1 entry inhibitors

  16. Expression of HIV-1 antigens in plants as potential subunit vaccines

    CSIR Research Space (South Africa)

    Meyers, A

    2008-06-23

    Full Text Available Open AcceResearch article Expression of HIV-1 antigens in plants as potential subunit vaccines Ann Meyers1,2, Ereck Chakauya1,2,3, Enid Shephard1,4, Fiona L Tanzer1,2, James Maclean1,2, Alisson Lynch1,2, Anna-Lise Williamson1,5 and Edward P Rybicki...Figure 1 The HIV-1 Gag-derived proteins used in this study. Scale diagram showing (A) native Pr55Gag ORF organisation in the Page 2 of 15 (page number not for citation purposes) gag gene, (B) the p17/p24 fusion protein ORF, (C) p24 ORF. ORFs labelled p7...

  17. 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.

  18. Bacterial vaginosis associated with increased risk of female-to-male HIV-1 transmission: a prospective cohort analysis among African couples.

    Directory of Open Access Journals (Sweden)

    Craig R Cohen

    Full Text Available Bacterial vaginosis (BV, a disruption of the normal vaginal flora, has been associated with a 60% increased risk of HIV-1 acquisition in women and higher concentration of HIV-1 RNA in the genital tract of HIV-1-infected women. However, whether BV, which is present in up to half of African HIV-1-infected women, is associated with an increase in HIV-1 transmission to male partners has not been assessed in previous studies.We assessed the association between BV on female-to-male HIV-1 transmission risk in a prospective study of 2,236 HIV-1-seropositive women and their HIV-1 uninfected male partners from seven African countries from a randomized placebo-controlled trial that enrolled heterosexual African adults who were seropositive for both HIV-1 and herpes simplex virus (HSV-2, and their HIV-1-seronegative partners. Participants were followed for up to 24 months; every three months, vaginal swabs were obtained from female partners for Gram stain and male partners were tested for HIV-1. BV and normal vaginal flora were defined as a Nugent score of 7-10 and 0-3, respectively. To reduce misclassification, HIV-1 sequence analysis of viruses from seroconverters and their partners was performed to determine linkage of HIV-1 transmissions. Overall, 50 incident HIV-1 infections occurred in men in which the HIV-1-infected female partner had an evaluable vaginal Gram stain. HIV-1 incidence in men whose HIV-1-infected female partners had BV was 2.91 versus 0.76 per 100 person-years in men whose female partners had normal vaginal flora (hazard ratio 3.62, 95% CI 1.74-7.52. After controlling for sociodemographic factors, sexual behavior, male circumcision, sexually transmitted infections, pregnancy, and plasma HIV-1 RNA levels in female partners, BV was associated with a greater than 3-fold increased risk of female-to-male HIV-1 transmission (adjusted hazard ratio 3.17, 95% CI 1.37-7.33.This study identified an association between BV and increased risk of HIV

  19. eCD4-Ig variants that more potently neutralize HIV-1.

    Science.gov (United States)

    Fetzer, Ina; Gardner, Matthew R; Davis-Gardner, Meredith E; Prasad, Neha R; Alfant, Barnett; Weber, Jesse A; Farzan, Michael

    2018-03-28

    The HIV-1 entry inhibitor eCD4-Ig is a fusion of CD4-Ig and a coreceptor-mimetic peptide. eCD4-Ig is markedly more potent than CD4-Ig, with neutralization efficiencies approaching those of HIV-1 broadly neutralizing antibodies (bNAbs). However, unlike bNAbs, eCD4-Ig neutralizes all HIV-1, HIV-2 and SIV isolates that it has been tested against, suggesting that it may be useful in clinical settings where antibody escape is a concern. Here we characterize three new eCD4-Ig variants, each with different architectures and each utilizing D1.22, a stabilized form of CD4 domain 1. These variants were 10- to 20-fold more potent than our original eCD4-Ig variant, with a construct bearing four D1.22 domains (eD1.22-HL-Ig) exhibiting the greatest potency. However, this variant mediated less efficient antibody-dependent cell-mediated cytotoxicity (ADCC) activity than eCD4-Ig itself or several other eCD4-Ig variants, including the smallest variant (eD1.22-Ig). A variant with the same architecture as original eCD4-Ig (eD1.22-D2-Ig) showed modestly higher thermal stability and best prevented promotion of infection of CCR5-positive, CD4-negative cells. All three variants, and eCD4-Ig itself, mediated more efficient shedding of the HIV-1 envelope glycoprotein gp120 than did CD4-Ig. Finally, we show that only three D1.22 mutations contributed to the potency of eD1.22-D2-Ig, and that introduction of these changes into eCD4-Ig resulted in a variant 9-fold more potent than eCD4-Ig and 2-fold more potent than eD1.22-D2-Ig. These studies will assist in developing eCD4-Ig variants with properties optimized for prophylaxis, therapy, and cure applications. IMPORTANCE HIV-1 bNAbs have properties different from antiretroviral compounds. Specifically, antibodies can enlist immune effector cells to eliminate infected cells, whereas antiretroviral compounds simply interfere with various steps in the viral lifecycle. Unfortunately, HIV-1 is adept at evading antibody recognition, limiting the

  20. High-resolution deep sequencing reveals biodiversity, population structure, and persistence of HIV-1 quasispecies within host ecosystems

    Directory of Open Access Journals (Sweden)

    Yin Li

    2012-12-01

    Full Text Available Abstract Background Deep sequencing provides the basis for analysis of biodiversity of taxonomically similar organisms in an environment. While extensively applied to microbiome studies, population genetics studies of viruses are limited. To define the scope of HIV-1 population biodiversity within infected individuals, a suite of phylogenetic and population genetic algorithms was applied to HIV-1 envelope hypervariable domain 3 (Env V3 within peripheral blood mononuclear cells from a group of perinatally HIV-1 subtype B infected, therapy-naïve children. Results Biodiversity of HIV-1 Env V3 quasispecies ranged from about 70 to 270 unique sequence clusters across individuals. Viral population structure was organized into a limited number of clusters that included the dominant variants combined with multiple clusters of low frequency variants. Next generation viral quasispecies evolved from low frequency variants at earlier time points through multiple non-synonymous changes in lineages within the evolutionary landscape. Minor V3 variants detected as long as four years after infection co-localized in phylogenetic reconstructions with early transmitting viruses or with subsequent plasma virus circulating two years later. Conclusions Deep sequencing defines HIV-1 population complexity and structure, reveals the ebb and flow of dominant and rare viral variants in the host ecosystem, and identifies an evolutionary record of low-frequency cell-associated viral V3 variants that persist for years. Bioinformatics pipeline developed for HIV-1 can be applied for biodiversity studies of virome populations in human, animal, or plant ecosystems.

  1. [Study on the molecular-epidemiological characteristics of HIV-1 in Shenzhen, 1992-2008].

    Science.gov (United States)

    Zhao, Guang-lu; Yu, Wei; Zhang, Juan-juan; Chen, Lin; Feng, Tie-jian; Wang, Feng; Hong, Fu-chang; Wang, Xiao-hui; Li, Qing

    2012-01-01

    To investigate the epidemiological characteristics of HIV-1 subtype in Shenzhen from 1992 to 2008. 489 HIV-1 positive plasma samples were collected from 1992 to 2008 in Shenzhen. HIV-1 env genes were amplified by nested-PCR from RNA. Phylogenetic analysis was performed on data regarding the nucleotide sequence. A total of 464 sequences were amplified and genotyped. Data from this study revealed that CRF01_AE was a predominant HIV-1 subtype in Shenzhen (64.4%, 299/464), followed by subtypes CRF_BC (17.5%, 81/464), B' (14.7%, 68/464) and B (2.4%, 11/464). Subtype C (0.4%, 2/464), A1 (0.2%, 1/464), CRF02_AG (0.2%, 1/464) and CRF06_cpx (0.2%, 1/464) were also prevalent in Shenzhen. CRF01_AE and CRF_BC were predominant among heterosexuals, homosexuals and injection drug users, while B' was predominant among blood donors. Results from phylogenetic tree analysis showed that some of the HIV-1 clusters had been defined in CRF01_AE strains at different time or groups with different transmission routes. Cross-infections were also seen. CRF01_AE was the predominant HIV-1 subtype in Shenzhen while CRF_BC, B, B', C, A1, CRF02_AG and a small amount of CRF06_cpx or recombinant subtypes were prevalent in this city. Different subtypes showed great variation in the process of epidemics.

  2. HIV-1 Variants and Drug Resistance in Pregnant Women from Bata (Equatorial Guinea): 2012-2013.

    Science.gov (United States)

    Alvarez, Patricia; Fernández McPhee, Carolina; Prieto, Luis; Martín, Leticia; Obiang, Jacinta; Avedillo, Pedro; Vargas, Antonio; Rojo, Pablo; Benito, Agustín; Ramos, José Tomás; Holguín, África

    2016-01-01

    This is the first study describing drug resistance mutations (DRM) and HIV-1 variants among infected pregnant women in Equatorial Guinea (GQ), a country with high (6.2%) and increasing HIV prevalence. Dried blood spots (DBS) were collected from November 2012 to December 2013 from 69 HIV-1 infected women participating in a prevention of mother-to-child transmission program in the Hospital Regional of Bata and Primary Health Care Centre María Rafols, Bata, GQ. The transmitted (TDR) or acquired (ADR) antiretroviral drug resistance mutations at partial pol sequence among naive or antiretroviral therapy (ART)-exposed women were defined following WHO or IAS USA 2015 lists, respectively. HIV-1 variants were identified by phylogenetic analyses. A total of 38 of 69 HIV-1 specimens were successfully amplified and sequenced. Thirty (79%) belonged to ART-experienced women: 15 exposed to nucleoside reverse transcriptase inhibitors (NRTI) monotherapy, and 15 to combined ART (cART) as first regimen including two NRTI and one non-NRTI (NNRTI) or one protease inhibitor (PI). The TDR rate was only found for PI (3.4%). The ADR rate was 37.5% for NNRTI, 8.7% for NRTI and absent for PI or NRTI+NNRTI. HIV-1 group M non-B variants caused most (97.4%) infections, mainly (78.9%) recombinants: CRF02_AG (55.2%), CRF22_A101 (10.5%), subtype C (10.5%), unique recombinants (5.3%), and A3, D, F2, G, CRF06_cpx and CRF11_cpx (2.6% each). The high rate of ADR to retrotranscriptase inhibitors (mainly to NNRTIs) observed among pretreated pregnant women reinforces the importance of systematic DRM monitoring in GQ to reduce HIV-1 resistance transmission and to optimize first and second-line ART regimens when DRM are present.

  3. 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.

  4. Aqueous Extracts of the Marine Brown Alga Lobophora variegata Inhibit HIV-1 Infection at the Level of Virus Entry into Cells

    KAUST Repository

    Kremb, Stephan

    2014-08-21

    In recent years, marine algae have emerged as a rich and promising source of molecules with potent activities against various human pathogens. The widely distributed brown alga Lobophora variegata that is often associated with tropical coral reefs exerts strong antibacterial and antiprotozoal effects, but so far has not been associated with specific anti-viral activities. This study investigated potential HIV-1 inhibitory activity of L. variegata collected from different geographical regions, using a cell-based full replication HIV-1 reporter assay. Aqueous L. variegata extracts showed strong inhibitory effects on several HIV-1 strains, including drug-resistant and primary HIV-1 isolates, and protected even primary cells (PBMC) from HIV-1-infection. Anti-viral potency was related to ecological factors and showed clear differences depending on light exposition or epiphyte growth. Assays addressing early events of the HIV-1 replication cycle indicated that L. variegata extracts inhibited entry of HIV-1 into cells at a pre-fusion step possibly by impeding mobility of virus particles. Further characterization of the aqueous extract demonstrated that even high doses had only moderate effects on viability of cultured and primary cells (PBMCs). Imaging-based techniques revealed extract effects on the plasma membrane and actin filaments as well as induction of apoptosis at concentrations exceeding EC50 of anti-HIV-1 activity by more than 400 fold. In summary, we show for the first time that L. variegata extracts inhibit HIV-1 entry, thereby suggesting this alga as promising source for the development of novel HIV-1 inhibitors.

  5. The origin and emergence of an HIV-1 epidemic:

    DEFF Research Database (Denmark)

    Bruhn, Christian Anders Wathne; Audelin, Anne M.; Helleberg, Marie

    2014-01-01

    To describe, at patient-level detail, the determining events and factors involved in the development of a country's HIV-1 epidemic.......To describe, at patient-level detail, the determining events and factors involved in the development of a country's HIV-1 epidemic....

  6. 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...

  7. HIV-1 Nef control of cell signalling molecules: multiple strategies

    Indian Academy of Sciences (India)

    HIV-1 has at its disposal numerous proteins encoded by its genome which provide the required arsenal to establish and maintain infection in its host for a considerable number of years. One of the most important and enigmatic of these proteins is Nef. The Nef protein of HIV-1 plays a fundamental role in the virus life cycle.

  8. 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

  9. 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

  10. 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.

  11. 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.

  12. 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...

  13. Raltegravir with optimized background therapy for resistant HIV-1 infection

    DEFF Research Database (Denmark)

    Steigbigel, Roy T; Cooper, David A; Kumar, Princy N

    2008-01-01

    BACKGROUND: Raltegravir (MK-0518) is an inhibitor of human immunodeficiency virus type 1 (HIV-1) integrase active against HIV-1 susceptible or resistant to older antiretroviral drugs. METHODS: We conducted two identical trials in different geographic regions to evaluate the safety and efficacy of...

  14. Visualization of Content Release from Cell Surface-Attached Single HIV-1 Particles Carrying an Extra-Viral Fluorescent pH-Sensor.

    Science.gov (United States)

    Sood, Chetan; Marin, Mariana; Mason, Caleb S; Melikyan, Gregory B

    2016-01-01

    HIV-1 fusion leading to productive entry has long been thought to occur at the plasma membrane. However, our previous single virus imaging data imply that, after Env engagement of CD4 and coreceptors at the cell surface, the virus enters into and fuses with intracellular compartments. We were unable to reliably detect viral fusion at the plasma membrane. Here, we implement a novel virus labeling strategy that biases towards detection of virus fusion that occurs in a pH-neutral environment-at the plasma membrane or, possibly, in early pH-neutral vesicles. Virus particles are co-labeled with an intra-viral content marker, which is released upon fusion, and an extra-viral pH sensor consisting of ecliptic pHluorin fused to the transmembrane domain of ICAM-1. This sensor fully quenches upon virus trafficking to a mildly acidic compartment, thus precluding subsequent detection of viral content release. As an interesting secondary observation, the incorporation of the pH-sensor revealed that HIV-1 particles occasionally shuttle between neutral and acidic compartments in target cells expressing CD4, suggesting a small fraction of viral particles is recycled to the plasma membrane and re-internalized. By imaging viruses bound to living cells, we found that HIV-1 content release in neutral-pH environment was a rare event (~0.4% particles). Surprisingly, viral content release was not significantly reduced by fusion inhibitors, implying that content release was due to spontaneous formation of viral membrane defects occurring at the cell surface. We did not measure a significant occurrence of HIV-1 fusion at neutral pH above this defect-mediated background loss of content, suggesting that the pH sensor may destabilize the membrane of the HIV-1 pseudovirus and, thus, preclude reliable detection of single virus fusion events at neutral pH.

  15. Visualization of Content Release from Cell Surface-Attached Single HIV-1 Particles Carrying an Extra-Viral Fluorescent pH-Sensor.

    Directory of Open Access Journals (Sweden)

    Chetan Sood

    Full Text Available HIV-1 fusion leading to productive entry has long been thought to occur at the plasma membrane. However, our previous single virus imaging data imply that, after Env engagement of CD4 and coreceptors at the cell surface, the virus enters into and fuses with intracellular compartments. We were unable to reliably detect viral fusion at the plasma membrane. Here, we implement a novel virus labeling strategy that biases towards detection of virus fusion that occurs in a pH-neutral environment-at the plasma membrane or, possibly, in early pH-neutral vesicles. Virus particles are co-labeled with an intra-viral content marker, which is released upon fusion, and an extra-viral pH sensor consisting of ecliptic pHluorin fused to the transmembrane domain of ICAM-1. This sensor fully quenches upon virus trafficking to a mildly acidic compartment, thus precluding subsequent detection of viral content release. As an interesting secondary observation, the incorporation of the pH-sensor revealed that HIV-1 particles occasionally shuttle between neutral and acidic compartments in target cells expressing CD4, suggesting a small fraction of viral particles is recycled to the plasma membrane and re-internalized. By imaging viruses bound to living cells, we found that HIV-1 content release in neutral-pH environment was a rare event (~0.4% particles. Surprisingly, viral content release was not significantly reduced by fusion inhibitors, implying that content release was due to spontaneous formation of viral membrane defects occurring at the cell surface. We did not measure a significant occurrence of HIV-1 fusion at neutral pH above this defect-mediated background loss of content, suggesting that the pH sensor may destabilize the membrane of the HIV-1 pseudovirus and, thus, preclude reliable detection of single virus fusion events at neutral pH.

  16. 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

  17. HIV-1 protease inhibitory substances from Cassia garrettiana

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    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.

  18. A Scoring Tool to Identify East African HIV-1 Serodiscordant Partnerships with a High Likelihood of Pregnancy.

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    Renee Heffron

    Full Text Available HIV-1 prevention programs targeting HIV-1 serodiscordant couples need to identify couples that are likely to become pregnant to facilitate discussions about methods to minimize HIV-1 risk during pregnancy attempts (i.e. safer conception or effective contraception when pregnancy is unintended. A clinical prediction tool could be used to identify HIV-1 serodiscordant couples with a high likelihood of pregnancy within one year.Using standardized clinical prediction methods, we developed and validated a tool to identify heterosexual East African HIV-1 serodiscordant couples with an increased likelihood of becoming pregnant in the next year. Datasets were from three prospectively followed cohorts, including nearly 7,000 couples from Kenya and Uganda participating in HIV-1 prevention trials and delivery projects.The final score encompassed the age of the woman, woman's number of children living, partnership duration, having had condomless sex in the past month, and non-use of an effective contraceptive. The area under the curve (AUC for the probability of the score to correctly predict pregnancy was 0.74 (95% CI 0.72-0.76. Scores ≥ 7 predicted a pregnancy incidence of >17% per year and captured 78% of the pregnancies. Internal and external validation confirmed the predictive ability of the score.A pregnancy likelihood score encompassing basic demographic, clinical and behavioral factors defined African HIV-1 serodiscordant couples with high one-year pregnancy incidence rates. This tool could be used to engage African HIV-1 serodiscordant couples in counseling discussions about fertility intentions in order to offer services for safer conception or contraception that align with their reproductive goals.

  19. A Scoring Tool to Identify East African HIV-1 Serodiscordant Partnerships with a High Likelihood of Pregnancy.

    Science.gov (United States)

    Heffron, Renee; Cohen, Craig R; Ngure, Kenneth; Bukusi, Elizabeth; Were, Edwin; Kiarie, James; Mugo, Nelly; Celum, Connie; Baeten, Jared M

    2015-01-01

    HIV-1 prevention programs targeting HIV-1 serodiscordant couples need to identify couples that are likely to become pregnant to facilitate discussions about methods to minimize HIV-1 risk during pregnancy attempts (i.e. safer conception) or effective contraception when pregnancy is unintended. A clinical prediction tool could be used to identify HIV-1 serodiscordant couples with a high likelihood of pregnancy within one year. Using standardized clinical prediction methods, we developed and validated a tool to identify heterosexual East African HIV-1 serodiscordant couples with an increased likelihood of becoming pregnant in the next year. Datasets were from three prospectively followed cohorts, including nearly 7,000 couples from Kenya and Uganda participating in HIV-1 prevention trials and delivery projects. The final score encompassed the age of the woman, woman's number of children living, partnership duration, having had condomless sex in the past month, and non-use of an effective contraceptive. The area under the curve (AUC) for the probability of the score to correctly predict pregnancy was 0.74 (95% CI 0.72-0.76). Scores ≥ 7 predicted a pregnancy incidence of >17% per year and captured 78% of the pregnancies. Internal and external validation confirmed the predictive ability of the score. A pregnancy likelihood score encompassing basic demographic, clinical and behavioral factors defined African HIV-1 serodiscordant couples with high one-year pregnancy incidence rates. This tool could be used to engage African HIV-1 serodiscordant couples in counseling discussions about fertility intentions in order to offer services for safer conception or contraception that align with their reproductive goals.

  20. 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

  1. 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.

  2. The Depsipeptide Romidepsin Reverses HIV-1 Latency In Vivo.

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    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.

  3. 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.

  4. Biophysical characterization of V3-lipopeptide liposomes influencing HIV-1 infectivity

    International Nuclear Information System (INIS)

    Rizos, Apostolos K.; Baritaki, Stavroula; Tsikalas, Ioannis; Doetschman, David C.; Spandidos, Demetrios A.; Krambovitis, Elias

    2007-01-01

    The V3-loop of the HIV-1 gp120 alters host cell immune function and modulates infectivity. We investigated biophysical parameters of liposome constructs with embedded lipopeptides from the principle neutralizing domain of the V3-loop and their influence on viral infectivity. Dynamic light scattering measurements showed liposome supramolecular structures with hydrodynamic radius of the order of 900 and 1300 nm for plain and V3-lipopeptide liposomes. Electron paramagnetic resonance measurements showed almost identical local microenvironment. The difference in liposome hydrodynamic radius was attributed to the fluctuating ionic environment of the V3-lipopeptide liposomes. In vitro HIV-1 infectivity assays showed that plain liposomes reduced virus production in all cell cultures, probably due to the hydrophobic nature of the aggregates. Liposomes carrying V3-lipopeptides with different cationic potentials restored and even enhanced infectivity (p < 0.05). These results highlight the need for elucidation of the involvement of lipid bilayers as dynamic components in supramolecular structures and in HIV-1 fusion mechanisms

  5. 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.

  6. 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

  7. 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.

  8. 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.

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

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    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.

  10. The Major Genetic Determinants of HIV-1 Control Affect HLA Class I Peptide Presentation

    OpenAIRE

    Pereyra, Florencia; Jia, Xiaoming; McLaren, Paul J.; Telenti, Amalio; de Bakker, Paul I.W.; Walker, Bruce D.; Jia, Xiaoming; McLaren, Paul J.; Ripke, Stephan; Brumme, Chanson J.; Pulit, Sara L.; Telenti, Amalio; Carrington, Mary; Kadie, Carl M.; Carlson, Jonathan M.

    2010-01-01

    Infectious and inflammatory diseases have repeatedly shown strong genetic associations within the major histocompatibility complex (MHC); however, the basis for these associations remains elusive. To define host genetic effects on the outcome of a chronic viral infection, we performed genome-wide association analysis in a multiethnic cohort of HIV-1 controllers and progressors, and we analyzed the effects of individual amino acids within the classical human leukocyte antigen (HLA) proteins. W...

  11. 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.

  12. Correlates of HIV-1 genital shedding in Tanzanian women.

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    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.

  13. 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.

  14. HIV-1 Vif's Capacity To Manipulate the Cell Cycle Is Species Specific.

    Science.gov (United States)

    Evans, Edward L; Becker, Jordan T; Fricke, Stephanie L; Patel, Kishan; Sherer, Nathan M

    2018-04-01

    Cells derived from mice and other rodents exhibit profound blocks to HIV-1 virion production, reflecting species-specific incompatibilities between viral Tat and Rev proteins and essential host factors cyclin T1 (CCNT1) and exportin-1 (XPO1, also known as CRM1), respectively. To determine if mouse cell blocks other than CCNT1 and XPO1 affect HIV's postintegration stages, we studied HIV-1 NL4-3 gene expression in mouse NIH 3T3 cells modified to constitutively express HIV-1-compatible versions of CCNT1 and XPO1 (3T3.CX cells). 3T3.CX cells supported both Rev-independent and Rev-dependent viral gene expression and produced relatively robust levels of virus particles, confirming that CCNT1 and XPO1 represent the predominant blocks to these stages. Unexpectedly, however, 3T3.CX cells were remarkably resistant to virus-induced cytopathic effects observed in human cell lines, which we mapped to the viral protein Vif and its apparent species-specific capacity to induce G 2 /M cell cycle arrest. Vif was able to mediate rapid degradation of human APOBEC3G and the PPP2R5D regulatory B56 subunit of the PP2A phosphatase holoenzyme in mouse cells, thus demonstrating that Vif NL4-3 's modulation of the cell cycle can be functionally uncoupled from some of its other defined roles in CUL5-dependent protein degradation. Vif was also unable to induce G 2 /M cell cycle arrest in other nonhuman cell types, including cells derived from nonhuman primates, leading us to propose that one or more human-specific cofactors underpin Vif's ability to modulate the cell cycle. IMPORTANCE Cells derived from mice and other rodents exhibit profound blocks to HIV-1 replication, thus hindering the development of a low-cost small-animal model for studying HIV/AIDS. Here, we engineered otherwise-nonpermissive mouse cells to express HIV-1-compatible versions of two species-specific host dependency factors, cyclin T1 (CCNT1) and exportin-1 (XPO1) (3T3.CX cells). We show that 3T3.CX cells rescue HIV-1

  15. The software-defined fast post-processing for GEM soft x-ray diagnostics in the Tungsten Environment in Steady-state Tokamak thermal fusion reactor

    Science.gov (United States)

    Krawczyk, Rafał Dominik; Czarski, Tomasz; Linczuk, Paweł; Wojeński, Andrzej; Kolasiński, Piotr; GÄ ska, Michał; Chernyshova, Maryna; Mazon, Didier; Jardin, Axel; Malard, Philippe; Poźniak, Krzysztof; Kasprowicz, Grzegorz; Zabołotny, Wojciech; Kowalska-Strzeciwilk, Ewa; Malinowski, Karol

    2018-06-01

    This article presents a novel software-defined server-based solutions that were introduced in the fast, real-time computation systems for soft X-ray diagnostics for the WEST (Tungsten Environment in Steady-state Tokamak) reactor in Cadarache, France. The objective of the research was to provide a fast processing of data at high throughput and with low latencies for investigating the interplay between the particle transport and magnetohydrodynamic activity. The long-term objective is to implement in the future a fast feedback signal in the reactor control mechanisms to sustain the fusion reaction. The implemented electronic measurement device is anticipated to be deployed in the WEST. A standalone software-defined computation engine was designed to handle data collected at high rates in the server back-end of the system. Signals are obtained from the front-end field-programmable gate array mezzanine cards that acquire and perform a selection from the gas electron multiplier detector. A fast, authorial library for plasma diagnostics was written in C++. It originated from reference offline MATLAB implementations. They were redesigned for runtime analysis during the experiment in the novel online modes of operation. The implementation allowed the benchmarking, evaluation, and optimization of plasma processing algorithms with the possibility to check the consistency with reference computations written in MATLAB. The back-end software and hardware architecture are presented with data evaluation mechanisms. The online modes of operation for the WEST are discussed. The results concerning the performance of the processing and the introduced functionality are presented.

  16. HIV-1 Replication and the Cellular Eukaryotic Translation Apparatus

    Directory of Open Access Journals (Sweden)

    Santiago Guerrero

    2015-01-01

    Full Text Available Eukaryotic translation is a complex process composed of three main steps: initiation, elongation, and termination. During infections by RNA- and DNA-viruses, the eukaryotic translation machinery is used to assure optimal viral protein synthesis. Human immunodeficiency virus type I (HIV-1 uses several non-canonical pathways to translate its own proteins, such as leaky scanning, frameshifting, shunt, and cap-independent mechanisms. Moreover, HIV-1 modulates the host translation machinery by targeting key translation factors and overcomes different cellular obstacles that affect protein translation. In this review, we describe how HIV-1 proteins target several components of the eukaryotic translation machinery, which consequently improves viral translation and replication.

  17. 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...

  18. 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.

  19. Towards an HIV-1 cure: measuring the latent reservoir.

    Science.gov (United States)

    Bruner, Katherine M; Hosmane, Nina N; Siliciano, Robert F

    2015-04-01

    The latent reservoir (LR) of HIV-1 in resting memory CD4(+) T cells serves as a major barrier to curing HIV-1 infection. While many PCR- and culture-based assays have been used to measure the size of the LR, correlation between results of different assays is poor and recent studies indicate that no available assay provides an accurate measurement of reservoir size. The discrepancies between assays are a hurdle to clinical trials that aim to measure the efficacy of HIV-1 eradication strategies. Here we describe the advantages and disadvantages of various approaches to measuring the LR. Copyright © 2015 Elsevier Ltd. All rights reserved.

  20. Towards an HIV-1 cure: measuring the latent reservoir

    Science.gov (United States)

    Bruner, Katherine M.; Hosmane, Nina N.; Siliciano, Robert F.

    2015-01-01

    The latent reservoir of HIV-1 in resting memory CD4+ T cells serves as a major barrier to curing HIV-1 infection. While many PCR- and culture-based assays have been used to measure the size of the latent reservoir, correlation between results of different assays is poor and recent studies indicate that no available assay provides an accurate measurement of reservoir size. The discrepancies between assays are a hurdle to clinical trials that aim to measure the efficacy of HIV-1 eradication strategies. Here we describe the advantages and disadvantages of various approaches to measure the latent reservoir. PMID:25747663

  1. 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...

  2. Neutralizing antibody and anti-retroviral drug sensitivities of HIV-1 isolates resistant to small molecule CCR5 inhibitors

    International Nuclear Information System (INIS)

    Pugach, Pavel; Ketas, Thomas J.; Michael, Elizabeth; Moore, John P.

    2008-01-01

    The small molecule CCR5 inhibitors are a new class of drugs for treating infection by human immunodeficiency virus type 1 (HIV-1). They act by binding to the CCR5 co-receptor and preventing its use during HIV-1-cell fusion. Escape mutants can be raised against CCR5 inhibitors in vitro and will arise when these drugs are used clinically. Here, we have assessed the responses of CCR5 inhibitor-resistant viruses to other anti-retroviral drugs that act by different mechanisms, and their sensitivities to neutralizing antibodies (NAbs). The rationale for the latter study is that the resistance pathway for CCR5 inhibitors involves changes in the HIV-1 envelope glycoproteins (Env), which are also targets for NAbs. The escape mutants CC101.19 and D1/85.16 were selected for resistance to AD101 and vicriviroc (VVC), respectively, from the primary R5 HIV-1 isolate CC1/85. Each escape mutant was cross-resistant to other small molecule CCR5 inhibitors (aplaviroc, maraviroc, VVC, AD101 and CMPD 167), but sensitive to protein ligands of CCR5: the modified chemokine PSC-RANTES and the humanized MAb PRO-140. The resistant viruses also retained wild-type sensitivity to the nucleoside reverse transcriptase inhibitor (RTI) zidovudine, the non-nucleoside RTI nevirapine, the protease inhibitor atazanavir and other attachment and fusion inhibitors that act independently of CCR5 (BMS-806, PRO-542 and enfuvirtide). Of note is that the escape mutants were more sensitive than the parental CC1/85 isolate to a subset of neutralizing monoclonal antibodies and to some sera from HIV-1-infected people, implying that sequence changes in Env that confer resistance to CCR5 inhibitors can increase the accessibility of some NAb epitopes. The need to preserve NAb resistance may therefore be a constraint upon how escape from CCR5 inhibitors occurs in vivo

  3. 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

  4. 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

  5. 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

  6. 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

  7. Therapeutic strategies to fight HIV-1 latency: progress and challenges

    CSIR Research Space (South Africa)

    Manoto, Sello L

    2017-10-01

    Full Text Available —1112, 2017 Therapeutic strategies to fight HIV-1 latency: progress and challenges Sello Lebohang Manoto, Lebogang Thobakgale, Rudzani Malabi, Charles Maphanga, Saturnin Ombinda-Lemboumba, Patience Mthunzi-Kufa Abstract: The life...

  8. Distribution of HIV-1 resistance-conferring polymorphic alleles SDF ...

    Indian Academy of Sciences (India)

    Unknown

    involved with delay in disease progression. ... proteins in 525 healthy individuals without any history of HIV-1 infection from 11 diverse populations of ... in three populations (Yamani, Pathan and Kamma), all in low frequencies (i.e. 1% to 3%).

  9. 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

  10. 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.

  11. Towards HIV-1 remission: potential roles for broadly neutralizing antibodies.

    Science.gov (United States)

    Halper-Stromberg, Ariel; Nussenzweig, Michel C

    2016-02-01

    Current antiretroviral drug therapies do not cure HIV-1 because they do not eliminate a pool of long-lived cells harboring immunologically silent but replication-competent proviruses - termed the latent reservoir. Eliminating this reservoir and stimulating the immune response to control infection in the absence of therapy remain important but unsolved goals of HIV-1 cure research. Recently discovered broadly neutralizing antibodies (bNAbs) exhibit remarkable breadth and potency in their ability to neutralize HIV-1 in vitro, and recent studies have demonstrated new therapeutic applications for passively administered bNAbs in vivo. This Review discusses the roles bNAbs might play in HIV-1 treatment regimens, including prevention, therapy, and cure.

  12. 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).

  13. 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.

  14. Increased T cell trafficking as adjunct therapy for HIV-1

    OpenAIRE

    Fryer, HR; Wolinsky, SM; McLean, AR

    2018-01-01

    Although antiretroviral drug therapy suppresses human immunodeficiency virus-type 1 (HIV-1) to undetectable levels in the blood of treated individuals, reservoirs of replication competent HIV-1 endure. Upon cessation of antiretroviral therapy, the reservoir usually allows outgrowth of virus and approaches to targeting the reservoir have had limited success. Ongoing cycles of viral replication in regions with low drug penetration contribute to this persistence. Here, we use a mathematical mode...

  15. 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.

  16. 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.

  17. 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)

  18. 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.

  19. 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.

  20. 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.

  1. Is HIV-2- induced AIDS different from HIV-1-associated AIDS? Data from a West African clinic

    NARCIS (Netherlands)

    Martinez-Steele, Euridice; Awasana, Akum Aveika; Corrah, Tumani; Sabally, Saihou; van der Sande, Marianne; Jaye, Assan; Togun, Toyin; Sarge-Njie, Ramu; McConkey, Samuel J.; Whittle, Hilton; Schim van der Loeff, Maarten F.

    2007-01-01

    Although AIDS is less frequent following HIV-2 than HIV-1 infection, it is unclear whether the clinical picture and clinical course of AIDS are similar in the two infections. To compare the pattern of AIDS-defining events, CD4 cell count at the time of AIDS diagnosis, survival from time of AIDS, and

  2. The calculated genetic barrier for antiretroviral drug resistance substitutions is largely similar for different HIV-1 subtypes

    NARCIS (Netherlands)

    Vijver, D.A. van de; Wensing, A.M.J.; Angarano, G.; Asjo, B.; Balotta, C.; Camacho, R.; Chaix, M.; Costagliola, D.; De Luca, A.; Derdelinckx, I.; Grossman, Z.; Hamouda, O.; Hatzakis, A.; Hemmer, R.; Hoepelman, A.I.M.; Horban, A.; Korn, K.; Kücherer, C.; Leitner, T.; Loveday, C.; MacRae, E.; Maljkovic, I.; Mendoza, C. de; Meyer, L.; Nielsen, C.; Op de Coul, E.L.M.; Omaasen, V.; Paraskevis, D.; Perrin, L.; Puchhammer-Stöckl, E.; Salminen, M.; Schmit, J.; Scheider, F.; Schuurman, R.; Soriano, V.; Stanczak, G.; Stanojevic, M.; Vandamme, A.; Laethem, K. van; Violin, M.; Wilde, K.; Yerly, S.; Zazzi, M.; Boucher, C.A.B.

    The genetic barrier, defined as the number of mutations required to overcome drug-selective pressure, is an important factor for the development of HIV drug resistance. Because of high variability between subtypes, particular HIV-1 subtypes could have different genetic barriers for drug

  3. Inhibition of HIV-1 infection in ex vivo cervical tissue model of human vagina by palmitic acid; implications for a microbicide development.

    Directory of Open Access Journals (Sweden)

    Xudong Lin

    Full Text Available BACKGROUND: Approximately 80% of all new HIV-1 infections are acquired through sexual contact. Currently, there is no clinically approved microbicide, indicating a clear and urgent therapeutic need. We recently reported that palmitic acid (PA is a novel and specific inhibitor of HIV-1 fusion and entry. Mechanistically, PA inhibits HIV-1 infection by binding to a novel pocket on the CD4 receptor and blocks efficient gp120-to-CD4 attachment. Here, we wanted to assess the ability of PA to inhibit HIV-1 infection in cervical tissue ex vivo model of human vagina, and determine its effect on Lactobacillus (L species of probiotic vaginal flora. PRINCIPAL FINDINGS: Our results show that treatment with 100-200 µM PA inhibited HIV-1 infection in cervical tissue by up to 50%, and this treatment was not toxic to the tissue or to L. crispatus and jensenii species of vaginal flora. In vitro, in a cell free system that is independent of in vivo cell associated CD4 receptor; we determined inhibition constant (Ki to be ∼2.53 µM. SIGNIFICANCE: These results demonstrate utility of PA as a model molecule for further preclinical development of a safe and potent HIV-1 entry microbicide inhibitor.

  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. Complete dissociation of the HIV-1 gp41 ectodomain and membrane proximal regions upon phospholipid binding

    International Nuclear Information System (INIS)

    Roche, Julien; Louis, John M.; Aniana, Annie; Ghirlando, Rodolfo; Bax, Ad

    2015-01-01

    The envelope glycoprotein gp41 mediates the process of membrane fusion that enables entry of the HIV-1 virus into the host cell. Strong lipid affinity of the ectodomain suggests that its heptad repeat regions play an active role in destabilizing membranes by directly binding to the lipid bilayers and thereby lowering the free-energy barrier for membrane fusion. In such a model, immediately following the shedding of gp120, the N-heptad and C-heptad helices dissociate and melt into the host cell and viral membranes, respectively, pulling the destabilized membranes into juxtaposition, ready for fusion. Post-fusion, reaching the final 6-helix bundle (6HB) conformation then involves competition between intermolecular interactions needed for formation of the symmetric 6HB trimer and the membrane affinity of gp41’s ectodomain, including its membrane-proximal regions. Our solution NMR study of the structural and dynamic properties of three constructs containing the ectodomain of gp41 with and without its membrane-proximal regions suggests that these segments do not form inter-helical interactions until the very late steps of the fusion process. Interactions between the polar termini of the heptad regions, which are not associating with the lipid surface, therefore may constitute the main driving force initiating formation of the final post-fusion states. The absence of significant intermolecular ectodomain interactions in the presence of dodecyl phosphocholine highlights the importance of trimerization of gp41’s transmembrane helix to prevent complete dissociation of the trimer during the course of fusion

  6. Complete dissociation of the HIV-1 gp41 ectodomain and membrane proximal regions upon phospholipid binding

    Energy Technology Data Exchange (ETDEWEB)

    Roche, Julien; Louis, John M.; Aniana, Annie [National Institute of Diabetes and Digestive and Kidney Diseases, Laboratory of Chemical Physics (United States); Ghirlando, Rodolfo [National Institutes of Health, Laboratory of Molecular Biology, National Institute of Diabetes and Digestive and Kidney Diseases (United States); Bax, Ad, E-mail: bax@nih.gov [National Institute of Diabetes and Digestive and Kidney Diseases, Laboratory of Chemical Physics (United States)

    2015-04-15

    The envelope glycoprotein gp41 mediates the process of membrane fusion that enables entry of the HIV-1 virus into the host cell. Strong lipid affinity of the ectodomain suggests that its heptad repeat regions play an active role in destabilizing membranes by directly binding to the lipid bilayers and thereby lowering the free-energy barrier for membrane fusion. In such a model, immediately following the shedding of gp120, the N-heptad and C-heptad helices dissociate and melt into the host cell and viral membranes, respectively, pulling the destabilized membranes into juxtaposition, ready for fusion. Post-fusion, reaching the final 6-helix bundle (6HB) conformation then involves competition between intermolecular interactions needed for formation of the symmetric 6HB trimer and the membrane affinity of gp41’s ectodomain, including its membrane-proximal regions. Our solution NMR study of the structural and dynamic properties of three constructs containing the ectodomain of gp41 with and without its membrane-proximal regions suggests that these segments do not form inter-helical interactions until the very late steps of the fusion process. Interactions between the polar termini of the heptad regions, which are not associating with the lipid surface, therefore may constitute the main driving force initiating formation of the final post-fusion states. The absence of significant intermolecular ectodomain interactions in the presence of dodecyl phosphocholine highlights the importance of trimerization of gp41’s transmembrane helix to prevent complete dissociation of the trimer during the course of fusion.

  7. 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.

  8. 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 ...

  9. Human Polycomb group EED protein negatively affects HIV-1 assembly and release

    Directory of Open Access Journals (Sweden)

    Darlix Jean-Luc

    2007-06-01

    Full Text Available Abstract Background The human EED protein, a member of the superfamily of Polycomb group (PcG proteins with WD-40 repeats, has been found to interact with three HIV-1 components, namely the structural Gag matrix protein (MA, the integrase enzyme (IN and the Nef protein. The aim of the present study was to analyze the possible biological role of EED in HIV-1 replication, using the HIV-1-based vector HIV-Luc and EED protein expressed by DNA transfection of 293T cells. Results During the early phase of HIV-1 infection, a slight negative effect on virus infectivity occurred in EED-expressing cells, which appeared to be dependent on EED-MA interaction. At late times post infection, EED caused an important reduction of virus production, from 20- to 25-fold as determined by CAp24 immunoassay, to 10- to 80-fold based on genomic RNA levels, and this decrease was not due to a reduction of Gag protein synthesis. Coexpression of WTNef, or the non-N-myristoylated mutant NefG2A, restored virus yields to levels obtained in the absence of exogenous EED protein. This effect was not observed with mutant NefΔ57 mimicking the Nef core, or with the lipid raft-retargeted fusion protein LAT-Nef. LATAA-Nef, a mutant defective in the lipid raft addressing function, had the same anti-EED effect as WTNef. Cell fractionation and confocal imaging showed that, in the absence of Nef, EED mainly localized in membrane domains different from the lipid rafts. Upon co-expression with WTNef, NefG2A or LATAA-Nef, but not with NefΔ57 or LAT-Nef, EED was found to relocate into an insoluble fraction along with Nef protein. Electron microscopy of HIV-Luc producer cells overexpressing EED showed significant less virus budding at the cell surface compared to control cells, and ectopic assembly and clustering of nuclear pore complexes within the cytoplasm. Conclusion Our data suggested that EED exerted an antiviral activity at the late stage of HIV-1 replication, which included genomic

  10. HIV-1 Env and Nef Cooperatively Contribute to Plasmacytoid Dendritic Cell Activation via CD4-Dependent Mechanisms.

    Science.gov (United States)

    Reszka-Blanco, Natalia J; Sivaraman, Vijay; Zhang, Liguo; Su, Lishan

    2015-08-01

    Plasmacytoid dendritic cells (pDCs) are the major source of type I IFN (IFN-I) in response to human immunodeficiency virus type 1 (HIV-1) infection. pDCs are rapidly activated during HIV-1 infection and are implicated in reducing the early viral load, as well as contributing to HIV-1-induced pathogenesis. However, most cell-free HIV-1 isolates are inefficient in activating human pDCs, and the mechanisms of HIV-1 recognition by pDCs and pDC activation are not clearly defined. In this study, we report that two genetically similar HIV-1 variants (R3A and R3B) isolated from a rapid progressor differentially activated pDCs to produce alpha interferon (IFN-α). The highly pathogenic R3A efficiently activated pDCs to induce robust IFN-α production, while the less pathogenic R3B did not. The viral determinant for efficient pDC activation was mapped to the V1V2 region of R3A Env, which also correlated with enhanced CD4 binding activity. Furthermore, we showed that the Nef protein was also required for the activation of pDCs by R3A. Analysis of a panel of R3A Nef functional mutants demonstrated that Nef domains involved in CD4 downregulation were necessary for R3A to activate pDCs. Our data indicate that R3A-induced pDC activation depends on (i) the high affinity of R3A Env for binding the CD4 receptor and (ii) Nef activity, which is involved in CD4 downregulation. Our findings provide new insights into the mechanism by which HIV-1 induces IFN-α in pDCs, which contributes to pathogenesis. Plasmacytoid dendritic cells (pDCs) are the major type I interferon (IFN-I)-producing cells, and IFN-I actually contributes to pathogenesis during chronic viral infections. How HIV-1 activates pDCs and the roles of pDCs/IFN-I in HIV-1 pathogenesis remain unclear. We report here that the highly pathogenic HIV R3A efficiently activated pDCs to induce IFN-α production, while most HIV-1 isolates are inefficient in activating pDCs. We have discovered that R3A-induced pDC activation depends on

  11. Cervical Shedding of HIV-1 RNA Among Women With Low Levels of Viremia While Receiving Highly Active Antiretroviral Therapy

    Science.gov (United States)

    Neely, Michael N.; Benning, Lorie; Xu, Jiaao; Strickler, Howard D.; Greenblatt, Ruth M.; Minkoff, Howard; Young, Mary; Bremer, James; Levine, Alexandra M.; Kovacs, Andrea

    2011-01-01

    Background Among women with low o r undetectable quantities of HIV-1 RNA in plasma, factors associated with genital HIV-1 RNA shedding, including choice of treatment regimen, are poorly characterized. Methods We measured HIV-1 RNA in cervical swab specimens obtained from participants in the Women’s Interagency HIV Study who had concurrent plasma viral RNA levels <500 copies/mL, and we assessed factors associated with genital HIV shedding. The study was powered to determine the relative effects of antiretroviral protease inhibitors (PIs) versus nonnucleoside reverse transcriptase inhibitors (NNRTIs) on viral RNA shedding. Results Overall, 44 (15%) of 290 women had detectable HIV-1 RNA in cervical specimens. In the final multivariate model, shedding was independently associated with NNRTI (vs. PI) use (odds ratio [OR], 95% confidence interval [CI]: 2.24, 1.13 to 4.45) and illicit drug use (OR, 95% CI: 2.41, 0.96 to 5.69). Conclusions This is the largest study to define risks for genital HIV-1 RNA shedding in women with low/undetectable plasma virus. Shedding in this population was common, and NNRTI-based highly active antiretroviral therapy (HAART) (vs. PI-based HAART) was associated with genital HIV shedding. Further study is required to determine the impact of these findings on transmission of HIV from mother to child or to sexual partners. PMID:17106279

  12. Inhibition of infection and transmission of HIV-1 and lack of significant impact on the vaginal commensal lactobacilli by carbohydrate-binding agents.

    Science.gov (United States)

    Petrova, Mariya I; Mathys, Leen; Lebeer, Sarah; Noppen, Sam; Van Damme, Els J M; Tanaka, Haruo; Igarashi, Yasuhiro; Vaneechoutte, Mario; Vanderleyden, Jos; Balzarini, Jan

    2013-09-01

    A selection of carbohydrate-binding agents (CBAs) with different glycan specificities were evaluated for their inhibitory effect against HIV infection and transmission, and their interaction with vaginal commensal bacteria. Several assays were used for the antiviral evaluation: (i) cell-free virus infection of human CD4+ T lymphocyte C8166 cells; (ii) syncytium formation in co-cultures of persistently HIV-1-infected HUT-78/HIV-1 and non-infected CD4+ SupT1 cells; (iii) DC-SIGN-directed capture of HIV-1 particles; and (iv) transmission of DC-SIGN-captured HIV-1 particles to uninfected CD4+ C8166 cells. CBAs were also examined for their interaction with vaginal commensal lactobacilli using several viability, proliferation and adhesion assays. The CBAs showed efficient inhibitory activity in the nanomolar to low-micromolar range against four events that play a crucial role in HIV-1 infection and transmission: cell-free virus infection, fusion between HIV-1-infected and non-infected cells, HIV-1 capture by DC-SIGN and transmission of DC-SIGN-captured virus to T cells. As candidate microbicides should not interfere with the normal human microbiota, we examined the effect of CBAs against Lactobacillus strains, including a variety of vaginal strains, a gastrointestinal strain and several non-human isolates. None of the CBAs included in our studies inhibited the growth of these bacteria in several media, affected their viability or had any significant impact on their adhesion to HeLa cell monolayers. The CBAs in this study were inhibitory to HIV-1 in several in vitro infection and transmission models, and may therefore qualify as potential microbicide candidates. The lack of significant impact on commensal vaginal lactobacilli is an important property of these CBAs in view of their potential microbicidal use.

  13. 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.

  14. Diagnosing acute and prevalent HIV-1 infection in young African adults seeking care for fever: a systematic review and audit of current practice.

    Science.gov (United States)

    Prins, Henrieke A B; Mugo, Peter; Wahome, Elizabeth; Mwashigadi, Grace; Thiong'o, Alexander; Smith, Adrian; Sanders, Eduard J; Graham, Susan M

    2014-06-01

    Fever is a common complaint in HIV-1 infected adults and may be a presenting sign of acute HIV-1 infection (AHI). We investigated the extent to which HIV-1 infection was considered in the diagnostic evaluation of febrile adults in sub-Saharan Africa (SSA) through a systematic review of published literature and guidelines in the period 2003-2014. We also performed a detailed audit of current practice for the evaluation of febrile young adults in coastal Kenya. Our review identified 43 studies investigating the aetiology of fever in adult outpatients in SSA. While the guidelines identified recommend testing for HIV-1 infection, none mentioned AHI. In our audit of current practice at nine health facilities, only 189 out of 1173 (16.1%) patients, aged 18-29 years, were tested for HIV-1. In a detailed record review, only 2 out of 39 (5.1%) young adults seeking care for fever were tested for HIV-1, and the possibility of AHI was not mentioned. Available literature on adult outpatients presenting with fever is heavily focused on diagnosing malaria and guidelines are poorly defined in terms of evaluating aetiologies other than malaria. Current practice in coastal Kenya shows poor uptake of provider-initiated HIV-1 testing and AHI is not currently considered in the differential diagnosis. © The Author 2014. Published by Oxford University Press on behalf of Royal Society of Tropical Medicine and Hygiene.

  15. Engineering and exploitation of a fluorescent HIV-1 gp120 for live cell CD4 binding assays

    International Nuclear Information System (INIS)

    Costantini, Lindsey M.; Irvin, Susan C.; Kennedy, Steven C.; Guo, Feng; Goldstein, Harris; Herold, Betsy C.; Snapp, Erik L.

    2015-01-01

    The HIV-1 envelope glycoprotein, gp120, binds the host cell receptor, CD4, in the initial step of HIV viral entry and infection. This process is an appealing target for the development of inhibitory drugs and neutralizing antibodies. To study gp120 binding and intracellular trafficking, we engineered a fluorescent fusion of the humanized gp120 JRFL HIV-1 variant and GFP. Gp120-sfGFP is glycosylated with human sugars, robustly expressed, and secreted from cultured human cells. Protein dynamics, quality control, and trafficking can be visualized in live cells. The fusion protein can be readily modified with different gp120 variants or fluorescent proteins. Finally, secreted gp120-sfGFP enables a sensitive and easy binding assay that can quantitatively screen potential inhibitors of gp120-CD4 binding on live cells via fluorescence imaging or laser scanning cytometry. This adaptable research tool should aid in studies of gp120 cell biology and the development of novel anti-HIV drugs. - Highlights: • Development of fluorescent protein labeled HIV-1 envelope gp120. • Imaging of gp120 dynamics and trafficking in live cells. • Quantitative visual assay of antibody-mediated inhibition of gp120 binding to CD4 on live cells

  16. Engineering and exploitation of a fluorescent HIV-1 gp120 for live cell CD4 binding assays

    Energy Technology Data Exchange (ETDEWEB)

    Costantini, Lindsey M. [Department of Anatomy and Structural Biology, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, NY 10461 (United States); Irvin, Susan C. [Department of Pediatrics, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, NY 10461 (United States); Department of Microbiology and Immunology, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, NY 10461 (United States); Kennedy, Steven C. [Department of Pediatrics, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, NY 10461 (United States); Guo, Feng [Department of Anatomy and Structural Biology, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, NY 10461 (United States); Goldstein, Harris; Herold, Betsy C. [Department of Pediatrics, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, NY 10461 (United States); Department of Microbiology and Immunology, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, NY 10461 (United States); Snapp, Erik L., E-mail: erik-lee.snapp@einstein.yu.edu [Department of Anatomy and Structural Biology, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, NY 10461 (United States)

    2015-02-15

    The HIV-1 envelope glycoprotein, gp120, binds the host cell receptor, CD4, in the initial step of HIV viral entry and infection. This process is an appealing target for the development of inhibitory drugs and neutralizing antibodies. To study gp120 binding and intracellular trafficking, we engineered a fluorescent fusion of the humanized gp120 JRFL HIV-1 variant and GFP. Gp120-sfGFP is glycosylated with human sugars, robustly expressed, and secreted from cultured human cells. Protein dynamics, quality control, and trafficking can be visualized in live cells. The fusion protein can be readily modified with different gp120 variants or fluorescent proteins. Finally, secreted gp120-sfGFP enables a sensitive and easy binding assay that can quantitatively screen potential inhibitors of gp120-CD4 binding on live cells via fluorescence imaging or laser scanning cytometry. This adaptable research tool should aid in studies of gp120 cell biology and the development of novel anti-HIV drugs. - Highlights: • Development of fluorescent protein labeled HIV-1 envelope gp120. • Imaging of gp120 dynamics and trafficking in live cells. • Quantitative visual assay of antibody-mediated inhibition of gp120 binding to CD4 on live cells.

  17. 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

  18. Fusion fuel and renewables

    International Nuclear Information System (INIS)

    Entler, Slavomir

    2015-01-01

    It is shown that fusion fuel meets all aspects applied when defining renewables. A table of definitions of renewables is presented. The sections of the paper are as follows: An industrial renewable source; Nuclear fusion; Current situation in research; Definitions of renewable sources; Energy concept of nuclear fusion; Fusion fuel; Natural energy flow; Environmental impacts; Fusion fuel assessment; Sustainable power; and Energy mix from renewables. (P.A.)

  19. Impaired production of cytokines is an independent predictor of mortality in HIV-1-infected patients

    DEFF Research Database (Denmark)

    Ostrowski, Sisse R; Gerstoft, Jan; Pedersen, Bente K

    2003-01-01

    With regard to the natural history of HIV-1 infection this study investigated whether whole-blood culture cytokine production was associated with mortality in HIV-1-infected patients.......With regard to the natural history of HIV-1 infection this study investigated whether whole-blood culture cytokine production was associated with mortality in HIV-1-infected patients....

  20. Interaction of small molecule inhibitors of HIV-1 entry with CCR5

    International Nuclear Information System (INIS)

    Seibert, Christoph; Ying Weiwen; Gavrilov, Svetlana; Tsamis, Fotini; Kuhmann, Shawn E.; Palani, Anandan; Tagat, Jayaram R.; Clader, John W.; McCombie, Stuart W.; Baroudy, Bahige M.; Smith, Steven O.; Dragic, Tatjana; Moore, John P.; Sakmar, Thomas P.

    2006-01-01

    The CC-chemokine receptor 5 (CCR5) is the major coreceptor for macrophage-tropic (R5) HIV-1 strains. Several small molecule inhibitors of CCR5 that block chemokine binding and HIV-1 entry are being evaluated as drug candidates. Here we define how CCR5 antagonists TAK-779, AD101 (SCH-350581) and SCH-C (SCH-351125), which inhibit HIV-1 entry, interact with CCR5. Using a mutagenesis approach in combination with a viral entry assay to provide a direct functional read out, we tested predictions based on a homology model of CCR5 and analyzed the functions of more than 30 amino acid residues. We find that a key set of aromatic and aliphatic residues serves as a hydrophobic core for the ligand binding pocket, while E283 is critical for high affinity interaction, most likely by acting as the counterion for a positively charged nitrogen atom common to all three inhibitors. These results provide a structural basis for understanding how specific antagonists interact with CCR5, and may be useful for the rational design of new, improved CCR5 ligands

  1. 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.

  2. 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.

  3. [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.

  4. 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.

  5. 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.

  6. 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.

  7. Antimalarial activity of HIV-1 protease inhibitor in chromone series.

    Science.gov (United States)

    Lerdsirisuk, Pradith; Maicheen, Chirattikan; Ungwitayatorn, Jiraporn

    2014-12-01

    Increasing parasite resistance to nearly all available antimalarial drugs becomes a serious problem to human health and necessitates the need to continue the search for new effective drugs. Recent studies have shown that clinically utilized HIV-1 protease (HIV-1 PR) inhibitors can inhibit the in vitro and in vivo growth of Plasmodium falciparum. In this study, a series of chromone derivatives possessing HIV-1 PR inhibitory activity has been tested for antimalarial activity against P. falciparum (K1 multi-drug resistant strain). Chromone 15, the potent HIV-1 PR inhibitor (IC50=0.65μM), was found to be the most potent antimalarial compound with IC50=0.95μM while primaquine and tafenoquine showed IC50=2.41 and 1.95μM, respectively. Molecular docking study of chromone compounds against plasmepsin II, an aspartic protease enzyme important in hemoglobin degradation, revealed that chromone 15 exhibited the higher binding affinity (binding energy=-13.24kcal/mol) than the known PM II inhibitors. Thus, HIV-1 PR inhibitor in chromone series has the potential to be a new class of antimalarial agent. Copyright © 2014 Elsevier Inc. All rights reserved.

  8. 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.

  9. 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

  10. A mechanistic understanding of allosteric immune escape pathways in the HIV-1 envelope glycoprotein.

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    Anurag Sethi

    Full Text Available The HIV-1 envelope (Env spike, which consists of a compact, heterodimeric trimer of the glycoproteins gp120 and gp41, is the target of neutralizing antibodies. However, the high mutation rate of HIV-1 and plasticity of Env facilitates viral evasion from neutralizing antibodies through various mechanisms. Mutations that are distant from the antibody binding site can lead to escape, probably by changing the conformation or dynamics of Env; however, these changes are difficult to identify and define mechanistically. Here we describe a network analysis-based approach to identify potential allosteric immune evasion mechanisms using three known HIV-1 Env gp120 protein structures from two different clades, B and C. First, correlation and principal component analyses of molecular dynamics (MD simulations identified a high degree of long-distance coupled motions that exist between functionally distant regions within the intrinsic dynamics of the gp120 core, supporting the presence of long-distance communication in the protein. Then, by integrating MD simulations with network theory, we identified the optimal and suboptimal communication pathways and modules within the gp120 core. The results unveil both strain-dependent and -independent characteristics of the communication pathways in gp120. We show that within the context of three structurally homologous gp120 cores, the optimal pathway for communication is sequence sensitive, i.e. a suboptimal pathway in one strain becomes the optimal pathway in another strain. Yet the identification of conserved elements within these communication pathways, termed inter-modular hotspots, could present a new opportunity for immunogen design, as this could be an additional mechanism that HIV-1 uses to shield vulnerable antibody targets in Env that induce neutralizing antibody breadth.

  11. The demise of multidrug-resistant HIV-1: the national time trend in Portugal.

    Science.gov (United States)

    Vercauteren, Jurgen; Theys, Kristof; Carvalho, Ana Patricia; Valadas, Emília; Duque, Luis Miguel; Teófilo, Eugénio; Faria, Telo; Faria, Domitília; Vera, José; Aguas, Maria João; Peres, Susana; Mansinho, Kamal; Vandamme, Anne-Mieke; Camacho, Ricardo Jorge

    2013-04-01

    Despite a decreasing mortality and morbidity in treated HIV-1 patients, highly active antiretroviral treatment (HAART) can still fail due to the development of drug resistance. Especially, multidrug-resistant viruses pose a threat to efficient therapy. We studied the changing prevalence of multidrug resistance (MDR) over time in a cohort of HIV-1-infected patients in Portugal. We used data of 8065 HIV-1-infected patients followed from July 2001 up to April 2012 in 22 hospitals located in Portugal. MDR at a specific date of sampling was defined as no more than one fully active drug (excluding integrase and entry inhibitors) at that time authorized by the Portuguese National Authority of Medicines and Health Products (INFARMED), as interpreted with the Rega algorithm version 8.0.2. A generalized linear mixed model was used to study the time trend of the prevalence of MDR. We observed a statistically significant decrease in the prevalence of MDR over the last decade, from 6.9% (95% CI: 5.7-8.4) in 2001-03, 6.0% (95% CI: 4.9-7.2) in 2003-05, 3.7% (95% CI: 2.8-4.8) in 2005-07 and 1.6% (95% CI: 1.1-2.2) in 2007-09 down to 0.6% (95% CI: 0.3-0.9) in 2009-12 [OR=0.80 (95% CI: 0.75-0.86); P<0.001]. In July 2011 the last new case of MDR was seen. The prevalence of multidrug-resistant HIV-1 is decreasing over time in Portugal, reflecting the increasing efficiency of HAART and the availability of new drugs. Therefore, in designing a new drug, safety and practical aspects, e.g. less toxicity and ease of use, may need more attention than focusing mainly on efficacy against resistant strains.

  12. 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.

  13. 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.

  14. Quantitative comparison of HTLV-1 and HIV-1 cell-to-cell infection with new replication dependent vectors.

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    Dmitriy Mazurov

    2010-02-01

    Full Text Available We have developed an efficient method to quantify cell-to-cell infection with single-cycle, replication dependent reporter vectors. This system was used to examine the mechanisms of infection with HTLV-1 and HIV-1 vectors in lymphocyte cell lines. Effector cells transfected with reporter vector, packaging vector, and Env expression plasmid produced virus-like particles that transduced reporter gene activity into cocultured target cells with zero background. Reporter gene expression was detected exclusively in target cells and required an Env-expression plasmid and a viral packaging vector, which provided essential structural and enzymatic proteins for virus replication. Cell-cell fusion did not contribute to infection, as reporter protein was rarely detected in syncytia. Coculture of transfected Jurkat T cells and target Raji/CD4 B cells enhanced HIV-1 infection two fold and HTLV-1 infection ten thousand fold in comparison with cell-free infection of Raji/CD4 cells. Agents that interfere with actin and tubulin polymerization strongly inhibited HTLV-1 and modestly decreased HIV-1 cell-to-cell infection, an indication that cytoskeletal remodeling was more important for HTLV-1 transmission. Time course studies showed that HTLV-1 transmission occurred very rapidly after cell mixing, whereas slower kinetics of HIV-1 coculture infection implies a different mechanism of infectious transmission. HTLV-1 Tax was demonstrated to play an important role in altering cell-cell interactions that enhance virus infection and replication. Interestingly, superantigen-induced synapses between Jurkat cells and Raji/CD4 cells did not enhance infection for either HTLV-1 or HIV-1. In general, the dependence on cell-to-cell infection was determined by the virus, the effector and target cell types, and by the nature of the cell-cell interaction.

  15. Back to the future: revisiting HIV-1 lethal mutagenesis

    Science.gov (United States)

    Dapp, Michael J.; Patterson, Steven E.; Mansky, Louis M.

    2012-01-01

    The concept of eliminating HIV-1 infectivity by elevating the viral mutation rate was first proposed over a decade ago, even though the general concept had been conceived earlier for RNA viruses. Lethal mutagenesis was originally viewed as a novel chemotherapeutic approach for treating HIV-1 infection in which use of a viral mutagen would over multiple rounds of replication lead to the lethal accumulation of mutations, rendering the virus population non infectious – known as the slow mutation accumulation model. There have been limitations in obtaining good efficacy data with drug leads, leaving some doubt into clinical translation. More recent studies of the APOBEC3 proteins as well as new progress in the use of nucleoside analogs for inducing lethal mutagenesis have helped to refocus attention on rapid induction of HIV-1 lethal mutagenesis in a single or limited number of replication cycles leading to a rapid mutation accumulation model. PMID:23195922

  16. Cellular and molecular mechanisms of HIV-1 integration targeting.

    Science.gov (United States)

    Engelman, Alan N; Singh, Parmit K

    2018-07-01

    Integration is central to HIV-1 replication and helps mold the reservoir of cells that persists in AIDS patients. HIV-1 interacts with specific cellular factors to target integration to interior regions of transcriptionally active genes within gene-dense regions of chromatin. The viral capsid interacts with several proteins that are additionally implicated in virus nuclear import, including cleavage and polyadenylation specificity factor 6, to suppress integration into heterochromatin. The viral integrase protein interacts with transcriptional co-activator lens epithelium-derived growth factor p75 to principally position integration within gene bodies. The integrase additionally senses target DNA distortion and nucleotide sequence to help fine-tune the specific phosphodiester bonds that are cleaved at integration sites. Research into virus-host interactions that underlie HIV-1 integration targeting has aided the development of a novel class of integrase inhibitors and may help to improve the safety of viral-based gene therapy vectors.

  17. Stable assembly of HIV-1 export complexes occurs cotranscriptionally

    DEFF Research Database (Denmark)

    Nawroth, Isabel; Mueller, Florian; Basyuk, Eugenia

    2014-01-01

    The HIV-1 Rev protein mediates export of unspliced and singly spliced viral transcripts by binding to the Rev response element (RRE) and recruiting the cellular export factor CRM1. Here, we investigated the recruitment of Rev to the transcription sites of HIV-1 reporters that splice either post......- or cotranscriptionally. In both cases, we observed that Rev localized to the transcription sites of the reporters and recruited CRM1. Rev and CRM1 remained at the reporter transcription sites when cells were treated with the splicing inhibitor Spliceostatin A (SSA), showing that the proteins associate with RNA prior...... to or during early spliceosome assembly. Fluorescence recovery after photobleaching (FRAP) revealed that Rev and CRM1 have similar kinetics as the HIV-1 RNA, indicating that Rev, CRM1, and RRE-containing RNAs are released from the site of transcription in one single export complex. These results suggest...

  18. Increased T cell trafficking as adjunct therapy for HIV-1

    Science.gov (United States)

    Wolinsky, Steven M.; McLean, Angela R.

    2018-01-01

    Although antiretroviral drug therapy suppresses human immunodeficiency virus-type 1 (HIV-1) to undetectable levels in the blood of treated individuals, reservoirs of replication competent HIV-1 endure. Upon cessation of antiretroviral therapy, the reservoir usually allows outgrowth of virus and approaches to targeting the reservoir have had limited success. Ongoing cycles of viral replication in regions with low drug penetration contribute to this persistence. Here, we use a mathematical model to illustrate a new approach to eliminating the part of the reservoir attributable to persistent replication in drug sanctuaries. Reducing the residency time of CD4 T cells in drug sanctuaries renders ongoing replication unsustainable in those sanctuaries. We hypothesize that, in combination with antiretroviral drugs, a strategy to orchestrate CD4 T cell trafficking could contribute to a functional cure for HIV-1 infection. PMID:29499057

  19. 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....

  20. Glycosylation in HIV-1 envelope glycoprotein and its biological implications

    KAUST Repository

    Ho, Yung Shwen

    2013-08-01

    Glycosylation of HIV-1 envelope proteins (Env gp120/gp41) plays a vital role in viral evasion from the host immune response, which occurs through the masking of key neutralization epitopes and the presentation of the Env glycosylation as \\'self\\' to the host immune system. Env glycosylation is generally conserved, yet its continual evolution plays an important role in modulating viral infectivity and Env immunogenicity. Thus, it is believed that Env glycosylation, which is a vital part of the HIV-1 architecture, also controls intra- and inter-clade genetic variations. Discerning intra- and inter-clade glycosylation variations could therefore yield important information for understanding the molecular and biological differences between HIV clades and may assist in effectively designing Env-based immunogens and in clearly understanding HIV vaccines. This review provides an in-depth perspective of various aspects of Env glycosylation in the context of HIV-1 pathogenesis. © 2013 Future Medicine Ltd.

  1. Redefining the Viral Reservoirs That Prevent HIV-1 Eradication

    Science.gov (United States)

    Eisele, Evelyn; Siliciano, Robert F.

    2014-01-01

    Summary This review proposes definitions for key terms in the field of HIV-1 latency and eradication. In the context of eradication, a reservoir is a cell type that allows persistence of replication-competent HIV-1 on a time scale of years in patients on optimal antiretroviral therapy. Reservoirs act as a barrier to eradication in the patient population in whom cure attempts will likely be made. Halting viral replication is essential to eradication, and definitions and criteria for assessing whether this goal has been achieved are proposed. The cell types that may serve as reservoirs for HIV-1 are discussed. Currently, only latently infected resting CD4+ T cells fit the proposed definition of a reservoir, and more evidence is necessary to demonstrate that other cell types including hematopoietic stem cells and macrophages fit this definition. Further research is urgently required on potential reservoirs in the gut-associated lymphoid tissue and the central nervous system. PMID:22999944

  2. 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

  3. 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.

  4. Flail arm-like syndrome associated with HIV-1 infection

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    Nalini A

    2009-01-01

    Full Text Available During the last 20 years at least 23 cases of motor neuron disease have been reported in HIV-1 seropositive patients. In this report we describe the clinical picture of a young man with HIV-1 clade C infection and flail arm-like syndrome, who we were able to follow-up for a long period. We investigated and prospectively monitored a 34-year-old man with features of flail arm syndrome, who developed the weakness and wasting 1 year after being diagnosed with HIV-1 infection after a routine blood test. He presented in 2003 with progressive, symmetrical wasting and weakness of the proximal muscles of the upper limb of 2 years′ duration. He had severe wasting and weakness of the shoulder and arm muscles. There were no pyramidal signs. He has been on HAART for the last 4 years and the weakness or wasting has not worsened. At the last follow-up in July 2007, the patient had the same neurological deficit and no other symptoms or signs of HIV-1 infection. MRI of the spinal cord in 2007 showed characteristic T2 hyperintense signals in the central part of the spinal cord, corresponding to the central gray matter. Thus, our patient had HIV-1 clade C infection associated with a ′flail arm-like syndrome.′ The causal relationship between HIV-1 infection and amyotrophic lateral sclerosis (ALS-like syndrome is still uncertain. The syndrome usually manifests as a lower motor neuron syndrome, as was seen in our young patient. It is known that treatment with antiretroviral therapy (ART stabilizes/improves the condition. In our patient the weakness and atrophy remained stable over a period of 3.5 years after commencing HAART regimen.

  5. 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.

  6. Human cellular restriction factors that target HIV-1 replication

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    Jeang Kuan-Teh

    2009-09-01

    Full Text Available Abstract Recent findings have highlighted roles played by innate cellular factors in restricting intracellular viral replication. In this review, we discuss in brief the activities of apolipoprotein B mRNA-editing enzyme 3G (APOBEC3G, bone marrow stromal cell antigen 2 (BST-2, cyclophilin A, tripartite motif protein 5 alpha (Trim5α, and cellular microRNAs as examples of host restriction factors that target HIV-1. We point to countermeasures encoded by HIV-1 for moderating the potency of these cellular restriction functions.

  7. Nucleocapsid promotes localization of HIV-1 gag to uropods that participate in virological synapses between T cells.

    Science.gov (United States)

    Llewellyn, G Nicholas; Hogue, Ian B; Grover, Jonathan R; Ono, Akira

    2010-10-28

    T cells adopt a polarized morphology in lymphoid organs, where cell-to-cell transmission of HIV-1 is likely frequent. However, despite the importance of understanding virus spread in vivo, little is known about the HIV-1 life cycle, particularly its late phase, in polarized T cells. Polarized T cells form two ends, the leading edge at the front and a protrusion called a uropod at the rear. Using multiple uropod markers, we observed that HIV-1 Gag localizes to the uropod in polarized T cells. Infected T cells formed contacts with uninfected target T cells preferentially via HIV-1 Gag-containing uropods compared to leading edges that lack plasma-membrane-associated Gag. Cell contacts enriched in Gag and CD4, which define the virological synapse (VS), are also enriched in uropod markers. These results indicate that Gag-laden uropods participate in the formation and/or structure of the VS, which likely plays a key role in cell-to-cell transmission of HIV-1. Consistent with this notion, a myosin light chain kinase inhibitor, which disrupts uropods, reduced virus particle transfer from infected T cells to target T cells. Mechanistically, we observed that Gag copatches with antibody-crosslinked uropod markers even in non-polarized cells, suggesting an association of Gag with uropod-specific microdomains that carry Gag to uropods. Finally, we determined that localization of Gag to the uropod depends on higher-order clustering driven by its NC domain. Taken together, these results support a model in which NC-dependent Gag accumulation to uropods establishes a preformed platform that later constitutes T-cell-T-cell contacts at which HIV-1 virus transfer occurs.

  8. Nucleocapsid promotes localization of HIV-1 gag to uropods that participate in virological synapses between T cells.

    Directory of Open Access Journals (Sweden)

    G Nicholas Llewellyn

    2010-10-01

    Full Text Available T cells adopt a polarized morphology in lymphoid organs, where cell-to-cell transmission of HIV-1 is likely frequent. However, despite the importance of understanding virus spread in vivo, little is known about the HIV-1 life cycle, particularly its late phase, in polarized T cells. Polarized T cells form two ends, the leading edge at the front and a protrusion called a uropod at the rear. Using multiple uropod markers, we observed that HIV-1 Gag localizes to the uropod in polarized T cells. Infected T cells formed contacts with uninfected target T cells preferentially via HIV-1 Gag-containing uropods compared to leading edges that lack plasma-membrane-associated Gag. Cell contacts enriched in Gag and CD4, which define the virological synapse (VS, are also enriched in uropod markers. These results indicate that Gag-laden uropods participate in the formation and/or structure of the VS, which likely plays a key role in cell-to-cell transmission of HIV-1. Consistent with this notion, a myosin light chain kinase inhibitor, which disrupts uropods, reduced virus particle transfer from infected T cells to target T cells. Mechanistically, we observed that Gag copatches with antibody-crosslinked uropod markers even in non-polarized cells, suggesting an association of Gag with uropod-specific microdomains that carry Gag to uropods. Finally, we determined that localization of Gag to the uropod depends on higher-order clustering driven by its NC domain. Taken together, these results support a model in which NC-dependent Gag accumulation to uropods establishes a preformed platform that later constitutes T-cell-T-cell contacts at which HIV-1 virus transfer occurs.

  9. A mature macrophage is a principal HIV-1 cellular reservoir in humanized mice after treatment with long acting antiretroviral therapy.

    Science.gov (United States)

    Araínga, Mariluz; Edagwa, Benson; Mosley, R Lee; Poluektova, Larisa Y; Gorantla, Santhi; Gendelman, Howard E

    2017-03-09

    Despite improved clinical outcomes seen following antiretroviral therapy (ART), resting CD4+ T cells continue to harbor latent human immunodeficiency virus type one (HIV-1). However, such cells are not likely the solitary viral reservoir and as such defining where and how others harbor virus is imperative for eradication measures. To such ends, we used HIV-1 ADA -infected NOD.Cg-Prkdc scid Il2rg tm1Wjl /SzJ mice reconstituted with a human immune system to explore two long-acting ART regimens investigating their abilities to affect viral cell infection and latency. At 6 weeks of infection animals were divided into four groups. One received long-acting (LA) cabotegravir (CAB) and rilpivirine (RVP) (2ART), a second received LA CAB, lamivudine, abacavir and RVP (4ART), a third were left untreated and a fourth served as an uninfected control. After 4 weeks of LA ART treatment, blood, spleen and bone marrow (BM) cells were collected then phenotypically characterized. CD4+ T cell subsets, macrophages and hematopoietic progenitor cells were analyzed for HIV-1 nucleic acids by droplet digital PCR. Plasma viral loads were reduced by two log 10 or to undetectable levels in the 2 and 4ART regimens, respectively. Numbers and distributions of CD4+ memory and regulatory T cells, macrophages and hematopoietic progenitor cells were significantly altered by HIV-1 infection and by both ART regimens. ART reduced viral DNA and RNA in all cell and tissue compartments. While memory cells were the dominant T cell reservoir, integrated HIV-1 DNA was also detected in the BM and spleen macrophages in both regimen-treated mice. Despite vigorous ART regimens, HIV-1 DNA and RNA were easily detected in mature macrophages supporting their potential role as an infectious viral reservoir.

  10. Novel gene fusion of PRCC-MITF defines a new member of MiT family translocation renal cell carcinoma: clinicopathological analysis and detection of the gene fusion by RNA sequencing and FISH.

    Science.gov (United States)

    Xia, Qiu-Yuan; Wang, Xiao-Tong; Ye, Sheng-Bing; Wang, Xuan; Li, Rui; Shi, Shan-Shan; Fang, Ru; Zhang, Ru-Song; Ma, Heng-Hui; Lu, Zhen-Feng; Shen, Qin; Bao, Wei; Zhou, Xiao-Jun; Rao, Qiu

    2018-04-01

    MITF, TFE3, TFEB and TFEC belong to the same microphthalmia-associated transcription factor family (MiT). Two transcription factors in this family have been identified in two unusual types of renal cell carcinoma (RCC): Xp11 translocation RCC harbouring TFE3 gene fusions and t(6;11) RCC harbouring a MALAT1-TFEB gene fusion. The 2016 World Health Organisation classification of renal neoplasia grouped these two neoplasms together under the category of MiT family translocation RCC. RCCs associated with the other two MiT family members, MITF and TFEC, have rarely been reported. Herein, we identify a case of MITF translocation RCC with the novel PRCC-MITF gene fusion by RNA sequencing. Histological examination of the present tumour showed typical features of MiT family translocation RCCs, overlapping with Xp11 translocation RCC and t(6;11) RCC. However, this tumour showed negative results in TFE3 and TFEB immunochemistry and split fluorescence in-situ hybridisation (FISH) assays. The other MiT family members, MITF and TFEC, were tested further immunochemically and also showed negative results. RNA sequencing and reverse transcription-polymerase chain reaction confirmed the presence of a PRCC-MITF gene fusion: a fusion of PRCC exon 5 to MITF exon 4. We then developed FISH assays covering MITF break-apart probes and PRCC-MITF fusion probes to detect the MITF gene rearrangement. This study both proves the recurring existence of MITF translocation RCC and expands the genotype spectrum of MiT family translocation RCCs. © 2017 John Wiley & Sons Ltd.

  11. 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

  12. 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

  13. 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.

  14. Evaluation of "credit card" libraries for inhibition of HIV-1 gp41 fusogenic core formation.

    Science.gov (United States)

    Xu, Yang; Lu, Hong; Kennedy, Jack P; Yan, Xuxia; McAllister, Laura A; Yamamoto, Noboru; Moss, Jason A; Boldt, Grant E; Jiang, Shibo; Janda, Kim D

    2006-01-01

    Protein-protein interactions are of critical importance in biological systems, and small molecule modulators of such protein recognition and intervention processes are of particular interest. To investigate this area of research, we have synthesized small-molecule libraries that can disrupt a number of biologically relevant protein-protein interactions. These library members are designed upon planar motif, appended with a variety of chemical functions, which we have termed "credit-card" structures. From two of our "credit-card" libraries, a series of molecules were uncovered which act as inhibitors against the HIV-1 gp41 fusogenic 6-helix bundle core formation, viral antigen p24 formation, and cell-cell fusion at low micromolar concentrations. From the high-throughput screening assays we utilized, a selective index (SI) value of 4.2 was uncovered for compound 2261, which bodes well for future structure activity investigations and the design of more potent gp41 inhibitors.

  15. Organization of cellular receptors into a nanoscale junction during HIV-1 adhesion.

    Directory of Open Access Journals (Sweden)

    Terrence M Dobrowsky

    2010-07-01

    Full Text Available The fusion of the human immunodeficiency virus type 1 (HIV-1 with its host cell is the target for new antiretroviral therapies. Viral particles interact with the flexible plasma membrane via viral surface protein gp120 which binds its primary cellular receptor CD4 and subsequently the coreceptor CCR5. However, whether and how these receptors become organized at the adhesive junction between cell and virion are unknown. Here, stochastic modeling predicts that, regarding binding to gp120, cellular receptors CD4 and CCR5 form an organized, ring-like, nanoscale structure beneath the virion, which locally deforms the plasma membrane. This organized adhesive junction between cell and virion, which we name the viral junction, is reminiscent of the well-characterized immunological synapse, albeit at much smaller length scales. The formation of an organized viral junction under multiple physiopathologically relevant conditions may represent a novel intermediate step in productive infection.

  16. The N-terminal domain of APJ, a CNS-based coreceptor for HIV-1, is essential for its receptor function and coreceptor activity

    International Nuclear Information System (INIS)

    Zhou Naiming; Zhang Xiaoling; Fan Xuejun; Argyris, Elias; Fang Jianhua; Acheampong, Edward; DuBois, Garrett C.; Pomerantz, Roger J.

    2003-01-01

    The human APJ, a G protein-coupled seven-transmembrane receptor, has been found to be dramatically expressed in the human central nervous system (CNS) and also to serve as a coreceptor for the entry of human immunodeficiency virus type 1 (HIV-1) and simian immunodeficiency virus (SIV). Studies with animal models suggested that APJ and its natural ligand, apelin, play an important role in the central control of body fluid homeostasis, and in regulation of blood pressure and cardiac contractility. In this study, we characterize the structural and functional determinants of the N-terminal domain of APJ in interactions with its natural ligand and HIV-1 envelope glycoprotein. We demonstrate that the second 10 residues of the N-terminal domain of APJ are critical for association with apelin, while the first 20 amino acids play an important role in supporting cell-cell fusion mediated by HIV-1 gp120. With site-directed mutagenesis, we have identified that the negatively charged amino acid residues Glu20 and Asp23 are involved in receptor and coreceptor functions, but residues Tyr10 and Tyr11 substantially contribute to coreceptor function for both T-tropic (CXCR4) and dual-tropic (CXCR4 and CCR5) HIV-1 isolates. Thus, this study provides potentially important information for further characterizing APJ-apelin functions in vitro and in vivo and designing small molecules for treatment of HIV-1 infection in the CNS

  17. Infection of human and non-human cells by a highly fusogenic primary CD4-independent HIV-1 isolate with a truncated envelope cytoplasmic tail

    International Nuclear Information System (INIS)

    Saha, Kunal; Yan Hui; Nelson, Julie A.E.; Zerhouni-Layachi, Bouchra

    2005-01-01

    Truncation of the envelope cytoplasmic tail has enabled FIV, SIV, and some laboratory HIV-1 strains to acquire broader cellular tropism and enhanced fusogenicity. Here we have characterized a primary CD4-independent HIV-1 isolate (92UG046-T8) with a truncated cytoplasmic tail that was able to infect and induce syncytia in primary lymphocytes from human, chimpanzee, and monkey, as well as CD4-negative cell lines from human and monkey. Increased syncytia were also noticeable with 293 cells expressing the cloned envelope from the 92UG046-T8 isolate suggesting envelope-mediated cellular fusion. Except pooled serum from HIV-1-infected individuals, monoclonal anti-envelope antibodies or antibodies/antagonists against CD4, CXCR4, and CCR5 were not able to prevent infection by the 92UG046-T8 isolate. This is the first report showing a primary HIV-1 variant with truncated cytoplasmic tail which is highly fusogenic and can infect a broad range of cells from human and non-human origins. In vivo evolution of similar HIV-1 mutants may have important implications in AIDS pathogenesis

  18. Different patterns of HIV-1 DNA after therapy discontinuation

    Directory of Open Access Journals (Sweden)

    Ghinelli Florio

    2005-09-01

    Full Text Available Abstract Background By persisting in infected cells for a long period of time, proviral HIV-1 DNA can represent an alternative viral marker to RNA viral load during the follow-up of HIV-1 infected individuals. In the present study sequential blood samples of 10 patients under antiretroviral treatment from 1997 with two NRTIs, who refused to continue any antiviral regimen, were analyzed for 16 – 24 weeks to study the possible relationship between DNA and RNA viral load. Methods The amount of proviral DNA was quantified by SYBR green real-time PCR in peripheral blood mononuclear cells from a selected group of ten patients with different levels of plasmatic viremia (RNA viral load. Results Variable levels of proviral DNA were found without any significant correlation between proviral load and plasma HIV-1 RNA levels. Results obtained showed an increase or a rebound in viral DNA in most patients, suggesting that the absence of therapy reflects an increase and/or a persistence of cells containing viral DNA. Conclusion Even though plasma HIV RNA levels remain the basic parameter to monitor the intensity of viral replication, the results obtained seem to indicate that DNA levels could represent an adjunct prognostic marker in monitoring HIV-1 infected subjects.

  19. APOBEC3G inhibits elongation of HIV-1 reverse transcripts.

    Directory of Open Access Journals (Sweden)

    Kate N Bishop

    2008-12-01

    Full Text Available APOBEC3G (A3G is a host cytidine deaminase that, in the absence of Vif, restricts HIV-1 replication and reduces the amount of viral DNA that accumulates in cells. Initial studies determined that A3G induces extensive mutation of nascent HIV-1 cDNA during reverse transcription. It has been proposed that this triggers the degradation of the viral DNA, but there is now mounting evidence that this mechanism may not be correct. Here, we use a natural endogenous reverse transcriptase assay to show that, in cell-free virus particles, A3G is able to inhibit HIV-1 cDNA accumulation not only in the absence of hypermutation but also without the apparent need for any target cell factors. We find that although reverse transcription initiates in the presence of A3G, elongation of the cDNA product is impeded. These data support the model that A3G reduces HIV-1 cDNA levels by inhibiting synthesis rather than by inducing degradation.

  20. Stepping toward a Macaque Model of HIV-1 Induced AIDS

    Directory of Open Access Journals (Sweden)

    Jason T. Kimata

    2014-09-01

    Full Text Available HIV-1 exhibits a narrow host range, hindering the development of a robust animal model of pathogenesis. Past studies have demonstrated that the restricted host range of HIV-1 may be largely due to the inability of the virus to antagonize and evade effector molecules of the interferon response in other species. They have also guided the engineering of HIV-1 clones that can replicate in CD4 T-cells of Asian macaque species. However, while replication of these viruses in macaque hosts is persistent, it has been limited and without progression to AIDS. In a new study, Hatziioannou et al., demonstrate for the first time that adapted macaque-tropic HIV-1 can persistently replicate at high levels in pigtailed macaques (Macaca nemestrina, but only if CD8 T-cells are depleted at the time of inoculation. The infection causes rapid disease and recapitulates several aspects of AIDS in humans. Additionally, the virus undergoes genetic changes to further escape innate immunity in association with disease progression. Here, the importance of these findings is discussed, as they relate to pathogenesis and model development.

  1. 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 t...

  2. Innate immune factors associated with HIV-1 transmission

    NARCIS (Netherlands)

    Pollakis, Georgios; Stax, Martijn J.; Paxton, William A.

    2011-01-01

    Relatively little is known with regards to the mechanisms of HIV-1 transmission across a mucosal surface and more specifically what effects host factors have on influencing infection and early viral dissemination. The purpose of this review is to summarize which factors of the innate immune response

  3. Recent evolutionary history of HIV-1 subtype B - Rebuttal

    NARCIS (Netherlands)

    Lukashov, V. V.; Goudsmit, J.

    2003-01-01

    The history of the HIV-1 B epidemic is the subject of a continuing debate. Did the epidemic start in the 1970s, as it was established based on the epidemiological data, or decades earlier, as it was suggested based on the analysis of nucleotide distances in the env gene? Our study [Lukashov and

  4. HIV-1 adaptation to NK cell-mediated immune pressure

    DEFF Research Database (Denmark)

    Elemans, Marjet; Boelen, Lies; Rasmussen, Michael

    2017-01-01

    The observation, by Alter et al., of the enrichment of NK cell “escape” variants in individuals carrying certain Killer-cell Immunoglobulin-like Receptor (KIR) genes is compelling evidence that natural killer (NK) cells exert selection pressure on HIV-1. Alter et al hypothesise that variant pepti...

  5. Incidence of HIV-1 infection and changes in prevalence of ...

    African Journals Online (AJOL)

    Sexual risk behaviours and RTIs may have contributed to HIV-1 transmission in this community. The data collected may help to inform the future design and evaluation of various intervention measures. Keywords: Africa, bacterial vaginosis, candidiasis, chlamydia, epidemiological synergy, gonorrhoea, incidence, sequelae

  6. 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

  7. HIV-1 isolation from infected peripheral blood mononuclear cells

    NARCIS (Netherlands)

    Dispinseri, Stefania; Saba, Elisa; Vicenzi, Elisa; Kootstra, Neeltje A.; Schuitemaker, Hanneke; Scarlatti, Gabriella

    2014-01-01

    Human immunodeficiency virus 1 (HIV-1) isolation from peripheral blood mononuclear cells (PBMCs) allows retrieval of replication-competent viral variants. In order to impose the smallest possible selective pressure on the viral isolates, isolation must be carried out in primary cultures of cells and

  8. The global spread of HIV-1 subtype B epidemic

    NARCIS (Netherlands)

    Magiorkinis, Gkikas; Angelis, Konstantinos; Mamais, Ioannis; Katzourakis, Aris; Hatzakis, Angelos; Albert, Jan; Lawyer, Glenn; Hamouda, Osamah; Struck, Daniel; Vercauteren, Jurgen; Wensing, Annemarie; Alexiev, Ivailo; Åsjö, Birgitta; Balotta, Claudia; Gomes, Perpétua; Camacho, Ricardo J.; Coughlan, Suzie; Griskevicius, Algirdas; Grossman, Zehava; Horban, Anders; Kostrikis, Leondios G.; Lepej, Snjezana J.; Liitsola, Kirsi; Linka, Marek; Nielsen, Claus; Otelea, Dan; Paredes, Roger; Poljak, Mario; Puchhammer-Stöckl, Elizabeth; Schmit, Jean Claude; Sönnerborg, Anders; Staneková, Danica; Stanojevic, Maja; Stylianou, Dora C.; Boucher, Charles A B; Nikolopoulos, Georgios; Vasylyeva, Tetyana; Friedman, Samuel R.; van de Vijver, David; Angarano, Gioacchino; Chaix, Marie Laure; de Luca, Andrea; Korn, Klaus; Loveday, Clive; Soriano, Vincent; Yerly, Sabine; Zazzi, Mauricio; Vandamme, Anne Mieke; Paraskevis, Dimitrios

    2016-01-01

    Human immunodeficiency virus type 1 (HIV-1) was discovered in the early 1980s when the virus had already established a pandemic. For at least three decades the epidemic in the Western World has been dominated by subtype B infections, as part of a sub-epidemic that traveled from Africa through Haiti

  9. 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.

  10. 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.

  11. Selection dramatically reduces effective population size in HIV-1 infection

    Directory of Open Access Journals (Sweden)

    Mittler John E

    2008-05-01

    Full Text Available Abstract Background In HIV-1 evolution, a 100–100,000 fold discrepancy between census size and effective population size (Ne has been noted. Although it is well known that selection can reduce Ne, high in vivo mutation and recombination rates complicate attempts to quantify the effects of selection on HIV-1 effective size. Results We use the inbreeding coefficient and the variance in allele frequency at a linked neutral locus to estimate the reduction in Ne due to selection in the presence of mutation and recombination. With biologically realistic mutation rates, the reduction in Ne due to selection is determined by the strength of selection, i.e., the stronger the selection, the greater the reduction. However, the dependence of Ne on selection can break down if recombination rates are very high (e.g., r ≥ 0.1. With biologically likely recombination rates, our model suggests that recurrent selective sweeps similar to those observed in vivo can reduce within-host HIV-1 effective population sizes by a factor of 300 or more. Conclusion Although other factors, such as unequal viral reproduction rates and limited migration between tissue compartments contribute to reductions in Ne, our model suggests that recurrent selection plays a significant role in reducing HIV-1 effective population sizes in vivo.

  12. Defective proviruses rapidly accumulate during acute HIV-1 infection

    Science.gov (United States)

    Bruner, Katherine M.; Murray, Alexandra J.; Pollack, Ross A.; Soliman, Mary G.; Laskey, Sarah B.; Capoferri, Adam A.; Lai, Jun; Strain, Matthew C.; Lada, Steven M.; Hoh, Rebecca; Ho, Ya-Chi; Richman, Douglas D.; Deeks, Steven G.; Siliciano, Janet D.; Siliciano, Robert F.

    2016-01-01

    Although antiretroviral therapy (ART) suppresses viral replication to clinically undetectable levels, HIV-1 persists in CD4+ T cells in a latent form not targeted by the immune system or ART1–5. This latent reservoir is a major barrier to cure. Many individuals initiate ART during chronic infection, and in this setting, most proviruses are defective6. However, the dynamics of the accumulation and persistence of defective proviruses during acute HIV-1 infection are largely unknown. Here we show that defective proviruses accumulate rapidly within the first few weeks of infection to make up over 93% of all proviruses, regardless of how early ART is initiated. Using an unbiased method to amplify near full-length proviral genomes from HIV-1 infected adults treated at different stages of infection, we demonstrate that early ART initiation limits the size of the reservoir but does not profoundly impact the proviral landscape. This analysis allows us to revise our understanding of the composition of proviral populations and estimate the true reservoir size in individuals treated early vs. late in infection. Additionally, we demonstrate that common assays for measuring the reservoir do not correlate with reservoir size. These findings reveal hurdles that must be overcome to successfully analyze future HIV-1 cure strategies. PMID:27500724

  13. 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.

  14. Analysis of dinucleotide signatures in HIV-1 subtype B genomes

    Indian Academy of Sciences (India)

    It was also shown that the profile generated by taking all dinucleotides together ... Keywords. genome signature; DRAP; HIV-1; chaos game representation. Journal of .... be used to quantify low levels of variation as are observed within species ..... Dayton A.I., Sodroski J.G., Rosen C.A., Goh W.C. and Haseltine. W.A. 1986 ...

  15. Distribution of HIV-1 resistance-conferring polymorphic alleles SDF ...

    Indian Academy of Sciences (India)

    Polymorphic allelic variants of chemokine receptors CCR2 and CCR5, as well as of stromal-derived factor-1 SDF-1, the ligand for the chemokine receptor CXCR4, are known to have protective effects against HIV-1 infection and to be involved with delay in disease progression. We have studied the DNA polymorphisms at ...

  16. 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.

  17. The global spread of HIV-1 subtype B epidemic

    NARCIS (Netherlands)

    G. Magiorkinis (Gkikas); K. Angelis (Konstantinos); I. Mamais (Ioannis); Katzourakis, A. (Aris); A. Hatzakis (Angelos); J. Albert (Jan); Lawyer, G. (Glenn); O. Hamouda (Osamah); D. Struck (Daniel); J. Vercauteren (Jurgen); A. Wensing (Amj); I. Alexiev (Ivailo); B. Åsjö (Birgitta); C. Balotta (Claudia); Gomes, P. (Perpétua); R.J. Camacho (Ricardo Jorge); S. Coughlan (Suzie); A. Griskevicius (Algirdas); Z. Grossman (Zehava); Horban, A. (Anders); L.G. Kostrikis (Leondios); Lepej, S.J. (Snjezana J.); K. Liitsola (Kirsi); M. Linka (Marek); C. Nielsen; D. Otelea (Dan); R. Paredes (Roger); M. Poljak (Mario); E. Puchhammer-Stöckl (Elisabeth); J.C. Schmit; A. Sonnerborg (Anders); D. Stanekova (Danica); M. Stanojevic (Maja); Stylianou, D.C. (Dora C.); C.A.B. Boucher (Charles); Nikolopoulos, G. (Georgios); Vasylyeva, T. (Tetyana); Friedman, S.R. (Samuel R.); D.A.M.C. van de Vijver (David); G. Angarano (Guiseppe); M.L. Chaix (Marie Laure); A. de Luca (Andrea); K. Korn (Klaus); Loveday, C. (Clive); V. Soriano (Virtudes); S. Yerly (Sabine); M. Zazzi; A.M. Vandamme (Anne Mieke); D. Paraskevis (Dimitrios)

    2016-01-01

    textabstractHuman immunodeficiency virus type 1 (HIV-1) was discovered in the early 1980s when the virus had already established a pandemic. For at least three decades the epidemic in the Western World has been dominated by subtype B infections, as part of a sub-epidemic that traveled from Africa

  18. Molecular epidemiology of HIV-1 infection in Europe: An overview.

    Science.gov (United States)

    Beloukas, Apostolos; Psarris, Alexandros; Giannelou, Polina; Kostaki, Evangelia; Hatzakis, Angelos; Paraskevis, Dimitrios

    2016-12-01

    Human Immunodeficiency Virus type 1 (HIV-1) is characterised by vast genetic diversity. Globally circulating HIV-1 viruses are classified into distinct phylogenetic strains (subtypes, sub-subtypes) and several recombinant forms. Here we describe the characteristics and evolution of European HIV-1 epidemic over time through a review of published literature and updated queries of existing HIV-1 sequence databases. HIV-1 in Western and Central Europe was introduced in the early-1980s in the form of subtype B, which is still the predominant clade. However, in Eastern Europe (Former Soviet Union (FSU) countries and Russia) the predominant strain, introduced into Ukraine in the mid-1990s, is subtype A (A FSU ) with transmission mostly occurring in People Who Inject Drugs (PWID). In recent years, the epidemic is evolving towards a complex tapestry with an increase in the prevalence of non-B subtypes and recombinants in Western and Central Europe. Non-B epidemics are mainly associated with immigrants, heterosexuals and females but more recently, non-B clades have also spread amongst groups where non-B strains were previously absent - non-immigrant European populations and amongst men having sex with men (MSM). In some countries, non-B clades have spread amongst the native population, for example subtype G in Portugal and subtype A in Greece, Albania and Cyprus. Romania provides a unique case where sub-subtype F1 has predominated throughout the epidemic. In contrast, HIV-1 epidemic in FSU countries remains more homogeneous with A FSU clade predominating in all countries. The differences between the evolution of the Western epidemic and the Eastern epidemic may be attributable to differences in transmission risk behaviours, lifestyle and the patterns of human mobility. The study of HIV-1 epidemic diversity provides a useful tool by which we can understand the history of the pandemic in addition to allowing us to monitor the spread and growth of the epidemic over time

  19. 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

  20. 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.

  1. Prevalence of genotypic HIV-1 drug resistance in Thailand, 2002

    Directory of Open Access Journals (Sweden)

    Watitpun Chotip

    2003-03-01

    Full Text Available Abstract Background The prices of reverse transcriptase (RT inhibitors in Thailand have been reduced since December 1, 2001. It is expected that reduction in the price of these inhibitors may influence the drug resistance mutation pattern of HIV-1 among infected people. This study reports the frequency of HIV-1 genetic mutation associated with drug resistance in antiretroviral-treated patients from Thailand. Methods Genotypic resistance testing was performed on samples collected in 2002 from 88 HIV-1 infected individuals. Automated DNA sequencing was used to genotype the HIV-1 polymerase gene isolated from patients' plasma. Results Resistance to protease inhibitors, nucleoside and non-nucleoside reverse transcriptase inhibitors were found in 10 (12%, 42 (48% and 19 (21% patients, respectively. The most common drug resistance mutations in the protease gene were at codon 82 (8%, 90 (7% and 54 (6%, whereas resistant mutations at codon 215 (45%, 67 (40%, 41 (38% and 184 (27% were commonly found in the RT gene. This finding indicates that genotypic resistance to nucleoside reverse transcriptase inhibitors was prevalent in 2002. The frequency of resistant mutations corresponding to non-nucleoside reverse transcriptase inhibitors was three times higher-, while resistant mutation corresponding to protease inhibitors was two times lower than those frequencies determined in 2001. Conclusion This study shows that the frequencies of RT inhibitor resistance mutations have been increased after the reduction in the price of RT inhibitors since December 2001. We believe that this was an important factor that influenced the mutation patterns of HIV-1 protease and RT genes in Thailand.

  2. 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.

  3. 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

  4. Probing the HIV-1 genomic RNA trafficking pathway and dimerization by genetic recombination and single virion analyses.

    Directory of Open Access Journals (Sweden)

    Michael D Moore

    2009-10-01

    Full Text Available Once transcribed, the nascent full-length RNA of HIV-1 must travel to the appropriate host cell sites to be translated or to find a partner RNA for copackaging to form newly generated viruses. In this report, we sought to delineate the location where HIV-1 RNA initiates dimerization and the influence of the RNA transport pathway used by the virus on downstream events essential to viral replication. Using a cell-fusion-dependent recombination assay, we demonstrate that the two RNAs destined for copackaging into the same virion select each other mostly within the cytoplasm. Moreover, by manipulating the RNA export element in the viral genome, we show that the export pathway taken is important for the ability of RNA molecules derived from two viruses to interact and be copackaged. These results further illustrate that at the point of dimerization the two main cellular export pathways are partially distinct. Lastly, by providing Gag in trans, we have demonstrated that Gag is able to package RNA from either export pathway, irrespective of the transport pathway used by the gag mRNA. These findings provide unique insights into the process of RNA export in general, and more specifically, of HIV-1 genomic RNA trafficking.

  5. Entry inhibitor-based microbicides are active in vitro against HIV-1 isolates from multiple genetic subtypes

    International Nuclear Information System (INIS)

    Ketas, Thomas J.; Schader, Susan M.; Zurita, Juan; Teo, Esther; Polonis, Victoria; Lu Min; Klasse, Per Johan; Moore, John P.

    2007-01-01

    Inhibitors of viral entry are under consideration as topical microbicides to prevent HIV-1 sexual transmission. Small molecules targeting HIV-1 gp120 (BMS-378806) or CCR5 (CMPD167), and a peptide fusion inhibitor (C52L), each blocks vaginal infection of macaques by a SHIV. A microbicide, however, must be active against multiple HIV-1 variants. We therefore tested BMS-C (a BMS-378806 derivative), CMPD167, C52L and the CXCR4 ligand AMD3465, alone and in combination, against 25 primary R5, 12 X4 and 7 R5X4 isolates from subtypes A-G. At high concentrations (0.1-1 μM), the replication of most R5 isolates in human donor lymphocytes was inhibited by > 90%. At lower concentrations, double and triple combinations were more effective than individual inhibitors. Similar results were obtained with X4 viruses when AMD3465 was substituted for CMPD167. The R5X4 viruses were inhibited by combining AMD3465 with CMPD167, or by the coreceptor-independent compounds. Thus, combining entry inhibitors may improve microbicide effectiveness

  6. Lipid raft-like liposomes used for targeted delivery of a chimeric entry-inhibitor peptide with anti-HIV-1 activity.

    Science.gov (United States)

    Gómara, María José; Pérez-Pomeda, Ignacio; Gatell, José María; Sánchez-Merino, Victor; Yuste, Eloisa; Haro, Isabel

    2017-02-01

    The work reports the design and synthesis of a chimeric peptide that is composed of the peptide sequences of two entry inhibitors which target different sites of HIV-1 gp41. The chimeric peptide offers the advantage of targeting two gp41 regions simultaneously: the fusion peptide and the loop both of which are membrane active and participate in the membrane fusion process. We therefore use lipid raft-like liposomes as a tool to specifically direct the chimeric inhibitor peptide to the membrane domains where the HIV-1 envelope protein is located. Moreover, the liposomes that mimic the viral membrane composition protect the chimeric peptide against proteolytic digestion thereby increasing the stability of the peptide. The described liposome preparations are suitable nanosystems for managing hydrophobic entry-inhibitor peptides as putative therapeutics. Copyright © 2016 Elsevier Inc. All rights reserved.

  7. Contrasting roles for TLR ligands in HIV-1 pathogenesis.

    Directory of Open Access Journals (Sweden)

    Beda Brichacek

    2010-09-01

    Full Text Available The first line of a host's response to various pathogens is triggered by their engagement of cellular pattern recognition receptors (PRRs. Binding of microbial ligands to these receptors leads to the induction of a variety of cellular factors that alter intracellular and extracellular environment and interfere directly or indirectly with the life cycle of the triggering pathogen. Such changes may also affect any coinfecting microbe. Using ligands to Toll-like receptors (TLRs 5 and 9, we examined their effect on human immunodeficiency virus (HIV-1 replication in lymphoid tissue ex vivo. We found marked differences in the outcomes of such treatment. While flagellin (TLR5 agonist treatment enhanced replication of CC chemokine receptor 5 (CCR 5-tropic and CXC chemokine receptor 4 (CXCR4-tropic HIV-1, treatment with oligodeoxynucleotide (ODN M362 (TLR9 agonist suppressed both viral variants. The differential effects of these TLR ligands on HIV-1 replication correlated with changes in production of CC chemokines CCL3, CCL4, CCL5, and of CXC chemokines CXCL10, and CXCL12 in the ligand-treated HIV-1-infected tissues. The nature and/or magnitude of these changes were dependent on the ligand as well as on the HIV-1 viral strain. Moreover, the tested ligands differed in their ability to induce cellular activation as evaluated by the expression of the cluster of differentiation markers (CD 25, CD38, CD39, CD69, CD154, and human leukocyte antigen D related (HLA-DR as well as of a cell proliferation marker, Ki67, and of CCR5. No significant effect of the ligand treatment was observed on apoptosis and cell death/loss in the treated lymphoid tissue ex vivo. Our results suggest that binding of microbial ligands to TLRs is one of the mechanisms that mediate interactions between coinfected microbes and HIV-1 in human tissues. Thus, the engagement of appropriate TLRs by microbial molecules or their mimetic might become a new strategy for HIV therapy or prevention.

  8. Real-time visualization of HIV-1 GAG trafficking in infected macrophages.

    Directory of Open Access Journals (Sweden)

    Karine Gousset

    2008-03-01

    Full Text Available HIV-1 particle production is driven by the Gag precursor protein Pr55(Gag. Despite significant progress in defining both the viral and cellular determinants of HIV-1 assembly and release, the trafficking pathway used by Gag to reach its site of assembly in the infected cell remains to be elucidated. The Gag trafficking itinerary in primary monocyte-derived macrophages is especially poorly understood. To define the site of assembly and characterize the Gag trafficking pathway in this physiologically relevant cell type, we have made use of the biarsenical-tetracysteine system. A small tetracysteine tag was introduced near the C-terminus of the matrix domain of Gag. The insertion of the tag at this position did not interfere with Gag trafficking, virus assembly or release, particle infectivity, or the kinetics of virus replication. By using this in vivo detection system to visualize Gag trafficking in living macrophages, Gag was observed to accumulate both at the plasma membrane and in an apparently internal compartment that bears markers characteristic of late endosomes or multivesicular bodies. Significantly, the internal Gag rapidly translocated to the junction between the infected macrophages and uninfected T cells following macrophage/T-cell synapse formation. These data indicate that a population of Gag in infected macrophages remains sequestered internally and is presented to uninfected target cells at a virological synapse.

  9. Genetic signatures in the envelope glycoproteins of HIV-1 that associate with broadly neutralizing antibodies.

    Directory of Open Access Journals (Sweden)

    S Gnanakaran

    Full Text Available A steady increase in knowledge of the molecular and antigenic structure of the gp120 and gp41 HIV-1 envelope glycoproteins (Env is yielding important new insights for vaccine design, but it has been difficult to translate this information to an immunogen that elicits broadly neutralizing antibodies. To help bridge this gap, we used phylogenetically corrected statistical methods to identify amino acid signature patterns in Envs derived from people who have made potently neutralizing antibodies, with the hypothesis that these Envs may share common features that would be useful for incorporation in a vaccine immunogen. Before attempting this, essentially as a control, we explored the utility of our computational methods for defining signatures of complex neutralization phenotypes by analyzing Env sequences from 251 clonal viruses that were differentially sensitive to neutralization by the well-characterized gp120-specific monoclonal antibody, b12. We identified ten b12-neutralization signatures, including seven either in the b12-binding surface of gp120 or in the V2 region of gp120 that have been previously shown to impact b12 sensitivity. A simple algorithm based on the b12 signature pattern was predictive of b12 sensitivity/resistance in an additional blinded panel of 57 viruses. Upon obtaining these reassuring outcomes, we went on to apply these same computational methods to define signature patterns in Env from HIV-1 infected individuals who had potent, broadly neutralizing responses. We analyzed a checkerboard-style neutralization dataset with sera from 69 HIV-1-infected individuals tested against a panel of 25 different Envs. Distinct clusters of sera with high and low neutralization potencies were identified. Six signature positions in Env sequences obtained from the 69 samples were found to be strongly associated with either the high or low potency responses. Five sites were in the CD4-induced coreceptor binding site of gp120, suggesting an

  10. Laser irradiation reduces HIV-1 infection in TZM-bl cells

    CSIR Research Space (South Africa)

    Lugongolo, Masixole Y

    2016-10-01

    Full Text Available HIV-1 epidemic remains a major health challenge. This study explores the effects of low level laser therapy on HIV-1 infected cells. Infection is reduced by irradiation and the mechanism needs to be investigated further....

  11. Defining the HLA class I-associated viral antigen repertoire from HIV-1-infected human cells

    DEFF Research Database (Denmark)

    Ternette, Nicola; Yang, Hongbing; Partridge, Thomas

    2016-01-01

    Recognition and eradication of infected cells by cytotoxic T lymphocytes is a key defense mechanism against intracellular pathogens. High-throughput definition of HLA class I-associated immunopeptidomes by mass spectrometry is an increasingly important analytical tool to advance our understanding...

  12. HIV-1 isolation from infected peripheral blood mononuclear cells.

    Science.gov (United States)

    Dispinseri, Stefania; Saba, Elisa; Vicenzi, Elisa; Kootstra, Neeltje A; Schuitemaker, Hanneke; Scarlatti, Gabriella

    2014-01-01

    Human immunodeficiency virus 1 (HIV-1) isolation from peripheral blood mononuclear cells (PBMCs) allows retrieval of replication-competent viral variants. In order to impose the smallest possible selective pressure on the viral isolates, isolation must be carried out in primary cultures of cells and not in tumor derived cell lines. The procedure involves culture of PBMCs from an infected patient with phytohemagglutinin (PHA)-stimulated PBMC from seronegative donors, which provide susceptible target cells for HIV replication. HIV can be isolated from the bulk population of PBMCs or after cloning of the cells to obtain viral biological clones. Viral production is determined with p24 antigen (Ag) detection assays or with reverse transcriptase (RT) activity assay. Once isolated, HIV-1 can be propagated by infecting PHA-stimulated PBMCs from healthy donors. Aliquots from culture with a high production of virus are stored for later use.

  13. 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

  14. Cytokine expression during syphilis infection in HIV-1-infected individuals

    DEFF Research Database (Denmark)

    Knudsen, Andreas; Benfield, Thomas; Kofoed, Kristian

    2009-01-01

    BACKGROUND: Little is known about cytokine responses to syphilis infection in HIV-1-infected individuals. METHODS: We retrospectively identified patients with HIV-1 and Treponema pallidum coinfection. Plasma samples from before, during, and after coinfection were analyzed for interleukin (IL)-2, IL......-4, IL-6, IL-8, IL-10, interferon (IFN)-gamma, and tumor necrosis factor (TNF)-alpha. RESULTS: Thirty-six patients were included. IL-10 levels increased significantly in patients with primary or secondary stage syphilis from a median of 12.8 pg/mL [interquartile range (IQR), 11.0-27.8] before...... infection to 46.7 pg/mL (IQR, 28.4-78.9) at the time of diagnosis (P = 0.027) and decreased to 13.0 pg/mL (IQR, 6.2-19.4) after treatment of syphilis (P syphilis in patients with primary or secondary stage syphilis (median 3.9 pg...

  15. 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.

  16. The highly conserved codon following the slippery sequence supports -1 frameshift efficiency at the HIV-1 frameshift site.

    Directory of Open Access Journals (Sweden)

    Suneeth F Mathew

    Full Text Available HIV-1 utilises -1 programmed ribosomal frameshifting to translate structural and enzymatic domains in a defined proportion required for replication. A slippery sequence, U UUU UUA, and a stem-loop are well-defined RNA features modulating -1 frameshifting in HIV-1. The GGG glycine codon immediately following the slippery sequence (the 'intercodon' contributes structurally to the start of the stem-loop but has no defined role in current models of the frameshift mechanism, as slippage is inferred to occur before the intercodon has reached the ribosomal decoding site. This GGG codon is highly conserved in natural isolates of HIV. When the natural intercodon was replaced with a stop codon two different decoding molecules-eRF1 protein or a cognate suppressor tRNA-were able to access and decode the intercodon prior to -1 frameshifting. This implies significant slippage occurs when the intercodon is in the (perhaps distorted ribosomal A site. We accommodate the influence of the intercodon in a model of frame maintenance versus frameshifting in HIV-1.

  17. Barriers to Antiretroviral Initiation in HIV-1-Discordant Couples

    Science.gov (United States)

    Guthrie, Brandon L.; Choi, Robert Y.; Liu, Amy Y.; Mackelprang, Romel D.; Rositch, Anne F.; Bosire, Rose; Manyara, Lucy; Gatuguta, Anne; Kiarie, James N.; Farquhar, Carey

    2011-01-01

    BACKGROUND In Kenya and much of sub-Saharan Africa, nearly half of all couples affected by HIV are discordant. Antiretroviral therapy (ART) slows disease progression in HIV-1-infected individuals, and reduces transmission to uninfected partners. We examined time to ART initiation and factors associated with delayed initiation in HIV-1-discordant couples in Nairobi. METHODS HIV-1-discordant couples were enrolled and followed quarterly for up to 2 years. Clinical staff administered questionnaires and conducted viral loads and CD4 counts. Participants with a CD4 count meeting ART criteria were referred to a nearby PEPFAR-funded treatment center. Barriers to ART initiation among participants with a CD4 count eligible for ART were assessed by Cox regression. RESULTS Of 439 HIV-1-infected participants (63.6% females and 36.4% males) 146 met CD4 count criteria for ART during follow-up. Median time from meeting CD4 criteria until ART initiation was 8.9 months, with 42.0% of eligible participants on ART by 6 months and 63.4% on ART by 1 year. The CD4 count at the time of eligibility was inversely associated with time to ART initiation (HR=0.49, p< 0.001). Compared to homeowners, those paying higher rents started ART 48% more slowly (p=0.062) and those paying lower rents started 71% more slowly (p=0.002). CONCLUSIONS Despite access to regular health care, referrals to treatment centers, and free access to ART, over a third of participants with an eligible CD4 count had not started ART within 1 year. Factors of lower socioeconomic status may slow ART initiation and targeted approaches are needed to avoid delays in treatment initiation. PMID:21826010

  18. HIV-1 Infection in adults with haematological malignancies in ...

    African Journals Online (AJOL)

    Burkett's lymphoma, Hodgkin's disease and myelodysplastic syndrome had been less frequently diagnosed. Forty-five of all cases (26.2%) had antibodies to the HIV-1 virus, predominantly in patients with Non-Hodgkin's lymphomas (p<0.001, OR=5.8, adjusted for age; CI=2.7 – 12.4). About 19.9% and 11.8% of cases with ...

  19. HIV-1 binding and neutralizing antibodies of injecting drug users

    Directory of Open Access Journals (Sweden)

    E.P. Ouverney

    2005-09-01

    Full Text Available Previous studies have demonstrated a stronger seroreactivity against some synthetic peptides responsible for inducing neutralizing antibodies in injecting drug users (IDU compared to that of individuals sexually infected with HIV-1 (S, but the effectiveness in terms of the neutralizing ability of these antibodies has not been evaluated. Our objective was to study the humoral immune response of IDU by determining the specificity of their antibodies and the presence of neutralizing antibodies. The neutralization capacity against the HIV-1 isolate MN (genotype B, the primary HIV-1 isolate 95BRRJ021 (genotype F, and the seroreactivity with peptides known to induce neutralizing antibodies, from the V2 and V3 loops of different HIV-1 subtypes, were analyzed. Seroreactivity indicates that IDU plasma are more likely to recognize a broader range of peptides than S plasma, with significantly higher titers, especially of V3 peptides. Similar neutralization frequencies of the MN isolate were observed in plasma of the IDU (16/47 and S (20/60 groups in the 1:10 dilution. The neutralization of the 95BRRJ021 isolate was more frequently observed for plasma from the S group (15/23 than from the IDU group (15/47, P = 0.0108. No correlation between neutralization and seroreactivity with the peptides tested was observed. These results suggest that an important factor responsible for the extensive and broad humoral immune response observed in IDU is their infection route. There was very little difference in neutralizing antibody response between the IDU and S groups despite their differences in seroreactivity and health status.

  20. nef gene sequence variation among HIV-1-infected African children

    Czech Academy of Sciences Publication Activity Database

    Chakraborty, R.; Reiniš, Milan; Rostron, T.; Philpott, S.; Dong, T.; D'Agostino, A.; Musoke, R.; de Silva, E.; Stumpf, M.; Weiser, B.; Burger, H.; Rowland-Jones, S.L.

    2006-01-01

    Roč. 7, č. 2 (2006), s. 75-84 ISSN 1464-2662 Grant - others:Fogarty International Center, NIH(US) 3D43TW00915; NIH(US) RO1 AI 42555 Institutional research plan: CEZ:AV0Z50520514 Keywords : HIV-1 nef gene * non-clade B * Kenya Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.674, year: 2006

  1. Somatic populations of PGT135-137 HIV-1-neutralizing antibodies identified by 454 pyrosequencing and bioinformatics

    Directory of Open Access Journals (Sweden)

    Jiang eZhu

    2012-09-01

    Full Text Available Select HIV-1-infected individuals develop sera capable of neutralizing diverse viral strains. The molecular basis of this neutralization is currently being deciphered by the isolation of HIV-1-neutralizing antibodies. In one infected donor, three neutralizing antibodies, PGT135-137, were identified by assessment of neutralization from individually sorted B cells and found to recognize an epitope containing an N-linked glycan at residue 332 on HIV-1 gp120. Here we use deep sequencing and bioinformatics methods to interrogate the B cell record of this donor to gain a more complete understanding of the humoral immune response. PGT135-137-gene family-specific primers were used to amplify heavy and light chain-variable domain sequences. 454 pyrosequencing produced 141,298 heavy-chain sequences of IGHV4-39 origin and 87,229 light-chain sequences of IGKV3-15 origin. A number of heavy and light chain sequences of ~90% identity to PGT137, several to PGT136, and none of high identity to PGT135 were identified. After expansion of these sequences to include close phylogenetic relatives, a total of 202 heavy-chain sequences and 72 light-chain sequences were identified. These sequences were clustered into populations of 95% identity comprising 15 for heavy chain and 10 for light chain, and a select sequence from each population was synthesized and reconstituted with a PGT137-partner chain. Reconstituted antibodies showed varied neutralization phenotypes for HIV-1 clade A and D isolates. Sequence diversity of the antibody population represented by these tested sequences was notably higher than observed with a 454 pyrosequencing-control analysis on 10 antibodies of defined sequence, suggesting that this diversity results primarily from somatic maturation. Our results thus provide an example of how pathogens like HIV-1 are opposed by a varied humoral immune response, derived from intrinsic mechanisms of antibody development, and embodied by somatic populations

  2. Dual R3R5 tropism characterizes cerebrospinal fluid HIV-1 isolates from individuals with high cerebrospinal fluid viral load.

    Science.gov (United States)

    Karlsson, Ulf; Antonsson, Liselotte; Ljungberg, Bengt; Medstrand, Patrik; Esbjörnsson, Joakim; Jansson, Marianne; Gisslen, Magnus

    2012-09-10

    To study the use of major and alternative coreceptors by HIV-1 isolates obtained from paired plasma and cerebrospinal fluid (CSF) samples. Paired plasma and CSF isolates from HIV-1-infected individuals with varying clinical, virologic, and immunologic parameters were assessed for the ability to infect indicator cells expressing a panel of coreceptors with documented expression in the central nervous system (CNS). HIV-1 isolates obtained from plasma and CSF in 28 individuals with varying viral load, CD4 T-cell counts, and with or without AIDS-defining disease were analyzed for the ability to infect NP2.CD4 cells stably expressing a panel of HIV coreceptors (CCR5, CXCR4, CCR3, CXCR6, GPR1, APJ, ChemR23, RDC-1 or BLT1). All isolates from both plasma and CSF utilized CCR5 and/or CXCR4. However, the ability to use both CCR3 and CCR5 (R3R5) was more pronounced in CSF isolates and correlated with high CSF viral load and low CD4 T-cell count. Notably, four out of five CSF isolates of subtype C origin exhibited CXCR6 use, which coincided with high CSF viral load despite preserved CD4 T-cell counts. The use of other alternative coreceptors was less pronounced. Dual-tropic R3R5 HIV-1 isolates in CSF coincide with high CSF viral load and low CD4 T-cell counts. Frequent CXCR6 use by CSF-derived subtype C isolates indicates that subtype-specific differences in coreceptor use may exist that will not be acknowledged when assessing plasma virus isolates. The findings may also bare relevance for HIV-1 replication within the CNS, and consequently, for the neuropathogenesis of AIDS.

  3. Discovery of novel targets for multi-epitope vaccines: Screening of HIV-1 genomes using association rule mining

    Directory of Open Access Journals (Sweden)

    Piontkivska Helen

    2009-07-01

    Full Text Available Abstract Background Studies have shown that in the genome of human immunodeficiency virus (HIV-1 regions responsible for interactions with the host's immune system, namely, cytotoxic T-lymphocyte (CTL epitopes tend to cluster together in relatively conserved regions. On the other hand, "epitope-less" regions or regions with relatively low density of epitopes tend to be more variable. However, very little is known about relationships among epitopes from different genes, in other words, whether particular epitopes from different genes would occur together in the same viral genome. To identify CTL epitopes in different genes that co-occur in HIV genomes, association rule mining was used. Results Using a set of 189 best-defined HIV-1 CTL/CD8+ epitopes from 9 different protein-coding genes, as described by Frahm, Linde & Brander (2007, we examined the complete genomic sequences of 62 reference HIV sequences (including 13 subtypes and sub-subtypes with approximately 4 representative sequences for each subtype or sub-subtype, and 18 circulating recombinant forms. The results showed that despite inclusion of recombinant sequences that would be expected to break-up associations of epitopes in different genes when two different genomes are recombined, there exist particular combinations of epitopes (epitope associations that occur repeatedly across the world-wide population of HIV-1. For example, Pol epitope LFLDGIDKA is found to be significantly associated with epitopes GHQAAMQML and FLKEKGGL from Gag and Nef, respectively, and this association rule is observed even among circulating recombinant forms. Conclusion We have identified CTL epitope combinations co-occurring in HIV-1 genomes including different subtypes and recombinant forms. Such co-occurrence has important implications for design of complex vaccines (multi-epitope vaccines and/or drugs that would target multiple HIV-1 regions at once and, thus, may be expected to overcome challenges

  4. The global spread of HIV-1 subtype B epidemic.

    Science.gov (United States)

    Magiorkinis, Gkikas; Angelis, Konstantinos; Mamais, Ioannis; Katzourakis, Aris; Hatzakis, Angelos; Albert, Jan; Lawyer, Glenn; Hamouda, Osamah; Struck, Daniel; Vercauteren, Jurgen; Wensing, Annemarie; Alexiev, Ivailo; Åsjö, Birgitta; Balotta, Claudia; Gomes, Perpétua; Camacho, Ricardo J; Coughlan, Suzie; Griskevicius, Algirdas; Grossman, Zehava; Horban, Anders; Kostrikis, Leondios G; Lepej, Snjezana J; Liitsola, Kirsi; Linka, Marek; Nielsen, Claus; Otelea, Dan; Paredes, Roger; Poljak, Mario; Puchhammer-Stöckl, Elizabeth; Schmit, Jean Claude; Sönnerborg, Anders; Staneková, Danica; Stanojevic, Maja; Stylianou, Dora C; Boucher, Charles A B; Nikolopoulos, Georgios; Vasylyeva, Tetyana; Friedman, Samuel R; van de Vijver, David; Angarano, Gioacchino; Chaix, Marie-Laure; de Luca, Andrea; Korn, Klaus; Loveday, Clive; Soriano, Vincent; Yerly, Sabine; Zazzi, Mauricio; Vandamme, Anne-Mieke; Paraskevis, Dimitrios

    2016-12-01

    Human immunodeficiency virus type 1 (HIV-1) was discovered in the early 1980s when the virus had already established a pandemic. For at least three decades the epidemic in the Western World has been dominated by subtype B infections, as part of a sub-epidemic that traveled from Africa through Haiti to United States. However, the pattern of the subsequent spread still remains poorly understood. Here we analyze a large dataset of globally representative HIV-1 subtype B strains to map their spread around the world over the last 50years and describe significant spread patterns. We show that subtype B travelled from North America to Western Europe in different occasions, while Central/Eastern Europe remained isolated for the most part of the early epidemic. Looking with more detail in European countries we see that the United Kingdom, France and Switzerland exchanged viral isolates with non-European countries than with European ones. The observed pattern is likely to mirror geopolitical landmarks in the post-World War II era, namely the rise and the fall of the Iron Curtain and the European colonialism. In conclusion, HIV-1 spread through specific migration routes which are consistent with geopolitical factors that affected human activities during the last 50years, such as migration, tourism and trade. Our findings support the argument that epidemic control policies should be global and incorporate political and socioeconomic factors. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

  5. 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

  6. Direct and dynamic detection of HIV-1 in living cells.

    Directory of Open Access Journals (Sweden)

    Jonas Helma

    Full Text Available In basic and applied HIV research, reliable detection of viral components is crucial to monitor progression of infection. While it is routine to detect structural viral proteins in vitro for diagnostic purposes, it previously remained impossible to directly and dynamically visualize HIV in living cells without genetic modification of the virus. Here, we describe a novel fluorescent biosensor to dynamically trace HIV-1 morphogenesis in living cells. We generated a camelid single domain antibody that specifically binds the HIV-1 capsid protein (CA at subnanomolar affinity and fused it to fluorescent proteins. The resulting fluorescent chromobody specifically recognizes the CA-harbouring HIV-1 Gag precursor protein in living cells and is applicable in various advanced light microscopy systems. Confocal live cell microscopy and super-resolution microscopy allowed detection and dynamic tracing of individual virion assemblies at the plasma membrane. The analysis of subcellular binding kinetics showed cytoplasmic antigen recognition and incorporation into virion assembly sites. Finally, we demonstrate the use of this new reporter in automated image analysis, providing a robust tool for cell-based HIV research.

  7. Innate immune reconstitution with suppression of HIV-1.

    Science.gov (United States)

    Scully, Eileen P; Lockhart, Ainsley; Garcia-Beltran, Wilfredo; Palmer, Christine D; Musante, Chelsey; Rosenberg, Eric; Allen, Todd M; Chang, J Judy; Bosch, Ronald J; Altfeld, Marcus

    2016-03-17

    Progressive HIV-1 infection leads to both profound immune suppression and pathologic inflammation in the majority of infected individuals. While adaptive immune dysfunction, as evidenced by CD4 + T cell depletion and exhaustion, has been extensively studied, less is known about the functional capacity of innate immune cell populations in the context of HIV-1 infection. Given the broad susceptibility to opportunistic infections and the dysregulated inflammation observed in progressive disease, we hypothesized that there would be significant changes in the innate cellular responses. Using a cohort of patients with multiple samplings before and after antiretroviral therapy (ART) initiation, we demonstrated increased responses to innate immune stimuli following viral suppression, as measured by the production of inflammatory cytokines. Plasma viral load itself had the strongest association with this change in innate functional capacity. We further identified epigenetic modifications in the TNFA promoter locus in monocytes that are associated with viremia, suggesting a molecular mechanism for the observed changes in innate immune function following initiation of ART. These data indicate that suppression of HIV-1 viremia is associated with changes in innate cellular function that may in part determine the restoration of protective immune responses.

  8. 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.

  9. Positron emission tomography in patients suffering from HIV-1 infection

    Energy Technology Data Exchange (ETDEWEB)

    Sathekge, Mike [University Hospital of Pretoria, Department of Nuclear Medicine, Pretoria (South Africa); Goethals, Ingeborg; Wiele, Christophe van de [University Hospital Ghent, Department of Nuclear Medicine, Ghent (Belgium); Maes, Alex [AZ Groening, Department of Nuclear Medicine, Kortrijk (Belgium)

    2009-07-15

    This paper reviews currently available PET studies performed either to improve our understanding of the pathogenesis of HIV-1 infection or to assess the value of PET imaging in the clinical decision making of patients infected with HIV-1 presenting with AIDS-related opportunistic infections and malignancies. FDG PET has shown that HIV-1 infection progresses by distinct anatomical steps, with involvement of the upper torso preceding involvement of the lower part of the torso, and that the degree of FDG uptake relates to viral load. The former finding suggests that lymphoid tissues are engaged in a predictable sequence and that diffusible mediators of activation might be important targets for vaccine or therapeutic intervention strategies. In lipodystrophic HIV-infected patients, limited available data support the hypothesis that stavudine-related lipodystrophy is associated with increased glucose uptake by adipose tissue as a result of the metabolic stress of adipose tissue in response to highly active antiretroviral treatment (HAART). Finally, in early AIDS-related dementia complex (ADC), striatal hypermetabolism is observed, whereas progressive ADC is characterized by a decrease in subcortical and cortical metabolism. In the clinical setting, PET has been shown to allow the differentiation of AIDS-related opportunistic infections and malignancies, and to allow monitoring of side effects of HAART. However, in patients suffering from HIV infection and presenting with extracerebral lymphoma or other human malignancies, knowledge of viraemia is essential when interpreting FDG PET imaging. (orig.)

  10. Positron emission tomography in patients suffering from HIV-1 infection

    International Nuclear Information System (INIS)

    Sathekge, Mike; Goethals, Ingeborg; Wiele, Christophe van de; Maes, Alex

    2009-01-01

    This paper reviews currently available PET studies performed either to improve our understanding of the pathogenesis of HIV-1 infection or to assess the value of PET imaging in the clinical decision making of patients infected with HIV-1 presenting with AIDS-related opportunistic infections and malignancies. FDG PET has shown that HIV-1 infection progresses by distinct anatomical steps, with involvement of the upper torso preceding involvement of the lower part of the torso, and that the degree of FDG uptake relates to viral load. The former finding suggests that lymphoid tissues are engaged in a predictable sequence and that diffusible mediators of activation might be important targets for vaccine or therapeutic intervention strategies. In lipodystrophic HIV-infected patients, limited available data support the hypothesis that stavudine-related lipodystrophy is associated with increased glucose uptake by adipose tissue as a result of the metabolic stress of adipose tissue in response to highly active antiretroviral treatment (HAART). Finally, in early AIDS-related dementia complex (ADC), striatal hypermetabolism is observed, whereas progressive ADC is characterized by a decrease in subcortical and cortical metabolism. In the clinical setting, PET has been shown to allow the differentiation of AIDS-related opportunistic infections and malignancies, and to allow monitoring of side effects of HAART. However, in patients suffering from HIV infection and presenting with extracerebral lymphoma or other human malignancies, knowledge of viraemia is essential when interpreting FDG PET imaging. (orig.)

  11. A Phase I Double Blind, Placebo-Controlled, Randomized Study of the Safety and Immunogenicity of an Adjuvanted HIV-1 Gag-Pol-Nef Fusion Protein and Adenovirus 35 Gag-RT-Int-Nef Vaccine in Healthy HIV-Uninfected African Adults.

    Directory of Open Access Journals (Sweden)

    Gloria Omosa-Manyonyi

    Full Text Available Sequential prime-boost or co-administration of HIV vaccine candidates based on an adjuvanted clade B p24, RT, Nef, p17 fusion protein (F4/AS01 plus a non-replicating adenovirus 35 expressing clade A Gag, RT, Int and Nef (Ad35-GRIN may lead to a unique immune profile, inducing both strong T-cell and antibody responses.In a phase 1, double-blind, placebo-controlled trial, 146 healthy adult volunteers were randomized to one of four regimens: heterologous prime-boost with two doses of F4/AS01E or F4/AS01B followed by Ad35-GRIN; Ad35-GRIN followed by two doses of F4/AS01B; or three co-administrations of Ad35-GRIN and F4/AS01B. T cell and antibody responses were measured.The vaccines were generally well-tolerated, and did not cause serious adverse events. The response rate, by IFN-γ ELISPOT, was greater when Ad35-GRIN was the priming vaccine and in the co-administration groups. F4/AS01 induced CD4+ T-cells expressing primarily CD40L and IL2 +/- TNF-α, while Ad35-GRIN induced predominantly CD8+ T-cells expressing IFN-γ +/- IL2 or TNF-α. Viral inhibition was induced after Ad35-GRIN vaccination, regardless of the regimen. Strong F4-specific antibody responses were induced. Immune responses persisted at least a year after the last vaccination. The complementary response profiles, characteristic of each vaccine, were both expressed after co-administration.Co-administration of an adjuvanted protein and an adenovirus vector showed an acceptable safety and reactogenicity profile and resulted in strong, multifunctional and complementary HIV-specific immune responses.ClinicalTrials.gov NCT01264445.

  12. Binding kinetics of aptamers to gp120 derived from HIV-1 subtype C

    CSIR Research Space (South Africa)

    Millroy, L

    2011-02-01

    Full Text Available aptamers with specific and strong affinity to the HIV-1 envelope glycoprotein gp120 and act as novel HIV-1 entry inhibitor drugs or as targeted drug delivery systems to HIV-1 infected cells. Prior to any downstream applications, novel gp120 aptamers need...

  13. Blocking type I interferon signaling enhances T cell recovery and reduces HIV-1 reservoirs.

    Science.gov (United States)

    Cheng, Liang; Ma, Jianping; Li, Jingyun; Li, Dan; Li, Guangming; Li, Feng; Zhang, Qing; Yu, Haisheng; Yasui, Fumihiko; Ye, Chaobaihui; Tsao, Li-Chung; Hu, Zhiyuan; Su, Lishan; Zhang, Liguo

    2017-01-03

    Despite the efficient suppression of HIV-1 replication that can be achieved with combined antiretroviral therapy (cART), low levels of type I interferon (IFN-I) signaling persist in some individuals. This sustained signaling may impede immune recovery and foster viral persistence. Here we report studies using a monoclonal antibody to block IFN-α/β receptor (IFNAR) signaling in humanized mice (hu-mice) that were persistently infected with HIV-1. We discovered that effective cART restored the number of human immune cells in HIV-1-infected hu-mice but did not rescue their immune hyperactivation and dysfunction. IFNAR blockade fully reversed HIV-1-induced immune hyperactivation and rescued anti-HIV-1 immune responses in T cells from HIV-1-infected hu-mice. Finally, we found that IFNAR blockade in the presence of cART reduced the size of HIV-1 reservoirs in lymphoid tissues and delayed HIV-1 rebound after cART cessation in the HIV-1-infected hu-mice. We conclude that low levels of IFN-I signaling contribute to HIV-1-associated immune dysfunction and foster HIV-1 persistence in cART-treated hosts. Our results suggest that blocking IFNAR may provide a potential strategy to enhance immune recovery and reduce HIV-1 reservoirs in individuals with sustained elevations in IFN-I signaling during suppressive cART.

  14. HIV-1 seroprevalence and subtypes in police recruits from Afar regional state, Ethiopia

    NARCIS (Netherlands)

    Zewde, Ayele; Bahiru, Seifu; Sanders, Eduard; Tilahun, Tesfaye; Beyene, Asfaw; Alebachew, Mengiste; Schaap, Ab; Wolday, Dawit; Rinke de Wit, Tobias F.

    2002-01-01

    Surveillance for HIV-1 prevalence and subtypes in Afar Region, Ethiopia was performed among police recruits in the year 2000, by unlinked anonymous testing. Of 408 samples tested, 26 (6.4%) appeared positive for HIV-1 antibodies. There was a trend for higher HIV-1 seroprevalence in women (9.5%,

  15. 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

  16. 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

  17. 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 ...

  18. 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.

  19. 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.

  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. 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.

  3. W-curve alignments for HIV-1 genomic comparisons.

    Directory of Open Access Journals (Sweden)

    Douglas J Cork

    2010-06-01

    Full Text Available The W-curve was originally developed as a graphical visualization technique for viewing DNA and RNA sequences. Its ability to render features of DNA also makes it suitable for computational studies. Its main advantage in this area is utilizing a single-pass algorithm for comparing the sequences. Avoiding recursion during sequence alignments offers advantages for speed and in-process resources. The graphical technique also allows for multiple models of comparison to be used depending on the nucleotide patterns embedded in similar whole genomic sequences. The W-curve approach allows us to compare large numbers of samples quickly.We are currently tuning the algorithm to accommodate quirks specific to HIV-1 genomic sequences so that it can be used to aid in diagnostic and vaccine efforts. Tracking the molecular evolution of the virus has been greatly hampered by gap associated problems predominantly embedded within the envelope gene of the virus. Gaps and hypermutation of the virus slow conventional string based alignments of the whole genome. This paper describes the W-curve algorithm itself, and how we have adapted it for comparison of similar HIV-1 genomes. A treebuilding method is developed with the W-curve that utilizes a novel Cylindrical Coordinate distance method and gap analysis method. HIV-1 C2-V5 env sequence regions from a Mother/Infant cohort study are used in the comparison.The output distance matrix and neighbor results produced by the W-curve are functionally equivalent to those from Clustal for C2-V5 sequences in the mother/infant pairs infected with CRF01_AE.Significant potential exists for utilizing this method in place of conventional string based alignment of HIV-1 genomes, such as Clustal X. With W-curve heuristic alignment, it may be possible to obtain clinically useful results in a short time-short enough to affect clinical choices for acute treatment. A description of the W-curve generation process, including a comparison

  4. W-curve alignments for HIV-1 genomic comparisons.

    Science.gov (United States)

    Cork, Douglas J; Lembark, Steven; Tovanabutra, Sodsai; Robb, Merlin L; Kim, Jerome H

    2010-06-01

    The W-curve was originally developed as a graphical visualization technique for viewing DNA and RNA sequences. Its ability to render features of DNA also makes it suitable for computational studies. Its main advantage in this area is utilizing a single-pass algorithm for comparing the sequences. Avoiding recursion during sequence alignments offers advantages for speed and in-process resources. The graphical technique also allows for multiple models of comparison to be used depending on the nucleotide patterns embedded in similar whole genomic sequences. The W-curve approach allows us to compare large numbers of samples quickly. We are currently tuning the algorithm to accommodate quirks specific to HIV-1 genomic sequences so that it can be used to aid in diagnostic and vaccine efforts. Tracking the molecular evolution of the virus has been greatly hampered by gap associated problems predominantly embedded within the envelope gene of the virus. Gaps and hypermutation of the virus slow conventional string based alignments of the whole genome. This paper describes the W-curve algorithm itself, and how we have adapted it for comparison of similar HIV-1 genomes. A treebuilding method is developed with the W-curve that utilizes a novel Cylindrical Coordinate distance method and gap analysis method. HIV-1 C2-V5 env sequence regions from a Mother/Infant cohort study are used in the comparison. The output distance matrix and neighbor results produced by the W-curve are functionally equivalent to those from Clustal for C2-V5 sequences in the mother/infant pairs infected with CRF01_AE. Significant potential exists for utilizing this method in place of conventional string based alignment of HIV-1 genomes, such as Clustal X. With W-curve heuristic alignment, it may be possible to obtain clinically useful results in a short time-short enough to affect clinical choices for acute treatment. A description of the W-curve generation process, including a comparison technique of

  5. 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.

  6. Minimal residual HIV viremia: verification of the Abbott Real-Time HIV-1 assay sensitivity

    Directory of Open Access Journals (Sweden)

    Alessandra Amendola

    2010-06-01

    Full Text Available Introduction: In the HIV-1 infection, the increase in number of CD4 T lymphocytes and the viral load decline are the main indicators of the effectiveness of antiretroviral therapy. On average, 85% of patients receiving effective treatment has a persistent suppression of plasma viral load below the detection limit (<50 copies/mL of clinically used viral load assays, regardless of treatment regimen in use. It is known, however, that, even when viremia is reduced below the sensitivity limit of current diagnostic assays, the virus persists in “reservoirs” and traces of free virions can be detected in plasma.There is a considerable interest to investigate the clinical significance of residual viremia. Advances in molecular diagnostics allows nowadays to couple a wide dynamic range to a high sensitivity.The Abbott Real-time HIV-1 test is linear from 40 to 107 copies/mL and provides, below 40 copies/mL, additional information such as “<40cp/mL, target detected” or “target not detected”. The HIV-1 detection is verified by the max-Ratio algorithm software.We assessed the test sensitivity when the qualitative response is considered as well. Methods: A ‘probit’ analysis was performed using dilutions of the HIV-1 RNA Working Reagent 1 for NAT assays (NIBSC code: 99/634, defined in IU/mL and different from that used by the manufacturer (VQA,Virology Quality Assurance Laboratory of the AIDS Clinical Trial Group for standardization and definition of performances.The sample input volume (0.6 mL was the same used in clinical routine. A total of 196 replicates at concentrations decreasing from 120 to 5 copies/mL, in three different sessions, have been tested.The ‘probit’ analysis (binomial dose-response model, 95% “hit-rate” has been carried out on the SAS 9.1.3 software package. Results: The sensitivity of the “<40cp/mL, target detected” response was equal to 28,76 copies/mL, with 95% confidence limits between 22,19 and 52,27 copies

  7. The demise of multidrug-resistant HIV-1: the national time trend in Portugal

    Science.gov (United States)

    Vercauteren, Jurgen; Theys, Kristof; Carvalho, Ana Patricia; Valadas, Emília; Duque, Luis Miguel; Teófilo, Eugénio; Faria, Telo; Faria, Domitília; Vera, José; Águas, Maria João; Peres, Susana; Mansinho, Kamal; Vandamme, Anne-Mieke; Camacho, Ricardo Jorge; Mansinho, Kamal; Cláudia Miranda, Ana; Aldir, Isabel; Ventura, Fernando; Nina, Jaime; Borges, Fernando; Valadas, Emília; Doroana, Manuela; Antunes, Francisco; João Aleixo, Maria; João Águas, Maria; Botas, Júlio; Branco, Teresa; Vera, José; Vaz Pinto, Inês; Poças, José; Sá, Joana; Duque, Luis; Diniz, António; Mineiro, Ana; Gomes, Flora; Santos, Carlos; Faria, Domitília; Fonseca, Paula; Proença, Paula; Tavares, Luís; Guerreiro, Cristina; Narciso, Jorge; Faria, Telo; Teófilo, Eugénio; Pinheiro, Sofia; Germano, Isabel; Caixas, Umbelina; Faria, Nancy; Paula Reis, Ana; Bentes Jesus, Margarida; Amaro, Graça; Roxo, Fausto; Abreu, Ricardo; Neves, Isabel

    2013-01-01

    Objectives Despite a decreasing mortality and morbidity in treated HIV-1 patients, highly active antiretroviral treatment (HAART) can still fail due to the development of drug resistance. Especially, multidrug-resistant viruses pose a threat to efficient therapy. We studied the changing prevalence of multidrug resistance (MDR) over time in a cohort of HIV-1-infected patients in Portugal. Patients and methods We used data of 8065 HIV-1-infected patients followed from July 2001 up to April 2012 in 22 hospitals located in Portugal. MDR at a specific date of sampling was defined as no more than one fully active drug (excluding integrase and entry inhibitors) at that time authorized by the Portuguese National Authority of Medicines and Health Products (INFARMED), as interpreted with the Rega algorithm version 8.0.2. A generalized linear mixed model was used to study the time trend of the prevalence of MDR. Results We observed a statistically significant decrease in the prevalence of MDR over the last decade, from 6.9% (95% CI: 5.7–8.4) in 2001–03, 6.0% (95% CI: 4.9–7.2) in 2003–05, 3.7% (95% CI: 2.8–4.8) in 2005–07 and 1.6% (95% CI: 1.1–2.2) in 2007–09 down to 0.6% (95% CI: 0.3–0.9) in 2009–12 [OR = 0.80 (95% CI: 0.75–0.86); P < 0.001]. In July 2011 the last new case of MDR was seen. Conclusions The prevalence of multidrug-resistant HIV-1 is decreasing over time in Portugal, reflecting the increasing efficiency of HAART and the availability of new drugs. Therefore, in designing a new drug, safety and practical aspects, e.g. less toxicity and ease of use, may need more attention than focusing mainly on efficacy against resistant strains. PMID:23228933

  8. Analysis of metabolic changes of brain in HIV-1 seropositive patients with proton magnetic resonance spectroscopy

    International Nuclear Information System (INIS)

    Koltowska, A.; Hendrich, B.; Sokolska, V.; Mis, M.; Lubkowska, K.; Szewczyk, P.; Sasiadek, M.; Furdal, M.; Knysz, B.; Gasiorowski, J.; Gladysz, A.

    2010-01-01

    Background: Asymptomatic central nervous system involvement may occur in the early stages of the HIV infection. The aim of the study was to evaluate early brain metabolic changes by means of proton MR spectroscopy (H1MRS) in the HIV-1 seropositive patients without neurological deficits or significant abnormalities in the plain MR study. Material/Methods: The H1MRS examinations were performed with the use of a MR GE Signa 1,5 T system. There were 39 subjects examined, aged 21 to 57 years (mean age 35 years) were examined, including 25 patients infected with HIV-1 and 14 healthy volunteers who constituted a control group. The examinations were performed using the Single Voxel Spectroscopy technique with the PRESS sequence, with following parameters: TR=1500 ms, TE=35 ms, number of acquisitions =128, time of acquisition =3 min. 43 sec. Voxels of 8 cm 3 (20 x 20 x 20 mm) in size were located in the following 5 regions: posterior cingulate gyrus, grey matter of the frontal area, left basal ganglia, white matter of the left parietal area and white matter of the frontal area. The NAA/Cr, Cho/Cr, mI/Cr ratios in the defined regions of interest were statistically analyzed. Results: There was a statistically significant decrease (p < 0.05) in the NAA/Cr ratios in the posterior cingulate area and white matter of the left parietal area in HIV-1 seropositive patients, as compared to the control group. Other metabolite ratios in all the above mentioned locations showed no statistically significant differences, as was also the case for NAA/Cr ratios in grey matter of the frontal area, left basal ganglia and white matter of the frontal area. Conclusions: The reduction of NAA/Cr values revealed in H1MRS studies suggests loss of neurons/neuronal activity in the posterior cingulate area and white matter of the left parietal area, in patients with HIV-1 at the stage before clinical manifestations of retroviral infection and structural changes in the plain MR study. This may reflect a

  9. Antibody to gp41 MPER alters functional properties of HIV-1 Env without complete neutralization.

    Directory of Open Access Journals (Sweden)

    Arthur S Kim

    2014-07-01

    Full Text Available Human antibody 10E8 targets the conserved membrane proximal external region (MPER of envelope glycoprotein (Env subunit gp41 and neutralizes HIV-1 with exceptional potency. Remarkably, HIV-1 containing mutations that reportedly knockout 10E8 binding to linear MPER peptides are partially neutralized by 10E8, producing a local plateau in the dose response curve. Here, we found that virus partially neutralized by 10E8 becomes significantly less neutralization sensitive to various MPER antibodies and to soluble CD4 while becoming significantly more sensitive to antibodies and fusion inhibitors against the heptad repeats of gp41. Thus, 10E8 modulates sensitivity of Env to ligands both pre- and post-receptor engagement without complete neutralization. Partial neutralization by 10E8 was influenced at least in part by perturbing Env glycosylation. With unliganded Env, 10E8 bound with lower apparent affinity and lower subunit occupancy to MPER mutant compared to wild type trimers. However, 10E8 decreased functional stability of wild type Env while it had an opposite, stabilizing effect on MPER mutant Envs. Clade C isolates with natural MPER polymorphisms also showed partial neutralization by 10E8 with altered sensitivity to various gp41-targeted ligands. Our findings suggest a novel mechanism of virus neutralization by demonstrating how antibody binding to the base of a trimeric spike cross talks with adjacent subunits to modulate Env structure and function. The ability of an antibody to stabilize, destabilize, partially neutralize as well as alter neutralization sensitivity of a virion spike pre- and post-receptor engagement may have implications for immunotherapy and vaccine design.

  10. In utero and intra-partum HIV-1 transmission and acute HIV-1 infection during pregnancy: using the BED capture enzyme-immunoassay as a surrogate marker for acute infection.

    Science.gov (United States)

    Marinda, Edmore T; Moulton, Lawrence H; Humphrey, Jean H; Hargrove, John W; Ntozini, Robert; Mutasa, Kuda; Levin, Jonathan

    2011-08-01

    The BED assay was developed to estimate the proportion of recent HIV infections in a population. We used the BED assay as a proxy for acute infection to quantify the associated risk of mother-to-child-transmission (MTCT) during pregnancy and delivery. Design A total of 3773 HIV-1 sero-positive women were tested within 96 h of delivery using the BED assay, and CD4 cell count measurements were taken. Mothers were classified according to their likelihood of having recently seroconverted. The risk of MTCT in utero and intra-partum was assessed comparing different groups defined by BED and CD4 cell count, adjusting for background factors using multinomial logistic models. Compared with women with BED ≥ 0.8/CD4 ≥ 350 (typical of HIV-1 chronic patients) there was insufficient evidence to conclude that women presenting with BED pregnancy.

  11. 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

  12. Canada's Fusion Program

    International Nuclear Information System (INIS)

    Jackson, D. P.

    1990-01-01

    Canada's fusion strategy is based on developing specialized technologies in well-defined areas and supplying these technologies to international fusion projects. Two areas are specially emphasized in Canada: engineered fusion system technologies, and specific magnetic confinement and materials studies. The Canadian Fusion Fuels Technology Project focuses on the first of these areas. It tritium and fusion reactor fuel systems, remote maintenance and related safety studies. In the second area, the Centre Canadian de fusion magnetique operates the Tokamak de Varennes, the main magnetic fusion device in Canada. Both projects are partnerships linking the Government of Canada, represented by Atomic Energy of Canada Limited, and provincial governments, electrical utilities, universities and industry. Canada's program has extensive international links, through which it collaborates with the major world fusion programs, including participation in the International Thermonuclear Experimental Reactor project

  13. 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.

  14. Acute HIV-1 infection is as common as malaria in young febrile adults seeking care in coastal Kenya.

    Science.gov (United States)

    Sanders, Eduard J; Mugo, Peter; Prins, Henrieke A B; Wahome, Elizabeth; Thiong'o, Alexander N; Mwashigadi, Grace; van der Elst, Elisabeth M; Omar, Anisa; Smith, Adrian D; Graham, Susan M

    2014-06-01

    Febrile adults are usually not tested for acute HIV-1 infection (AHI) in Africa. We assessed a strategy to diagnose AHI among young adult patients seeking care. Young adults (defined as a positive p24 antigen test, and subsequent seroconversion or RNA detection. Febrile patients evaluated for AHI were also screened for malaria using a rapid test, with PCR confirmation of positives. In 3602 adults seeking care, overall HIV-1 prevalence was 3.9%: 7.6% (68/897) among patients meeting AHI criteria vs. 2.6% (71/2705) among those who did not (P young febrile adults seeking care. An AHI detection strategy targeting young febrile adults seeking care at pharmacies and health facilities is feasible and should be considered as an HIV-prevention strategy in high-transmission settings.

  15. Particle infectivity of HIV-1 full-length genome infectious molecular clones in a subtype C heterosexual transmission pair following high fidelity amplification and unbiased cloning

    Energy Technology Data Exchange (ETDEWEB)

    Deymier, Martin J., E-mail: mdeymie@emory.edu [Emory Vaccine Center, Yerkes National Primate Research Center, 954 Gatewood Road NE, Atlanta, GA 30329 (United States); Claiborne, Daniel T., E-mail: dclaibo@emory.edu [Emory Vaccine Center, Yerkes National Primate Research Center, 954 Gatewood Road NE, Atlanta, GA 30329 (United States); Ende, Zachary, E-mail: zende@emory.edu [Emory Vaccine Center, Yerkes National Primate Research Center, 954 Gatewood Road NE, Atlanta, GA 30329 (United States); Ratner, Hannah K., E-mail: hannah.ratner@emory.edu [Emory Vaccine Center, Yerkes National Primate Research Center, 954 Gatewood Road NE, Atlanta, GA 30329 (United States); Kilembe, William, E-mail: wkilembe@rzhrg-mail.org [Zambia-Emory HIV Research Project (ZEHRP), B22/737 Mwembelelo, Emmasdale Post Net 412, P/BagE891, Lusaka (Zambia); Allen, Susan, E-mail: sallen5@emory.edu [Zambia-Emory HIV Research Project (ZEHRP), B22/737 Mwembelelo, Emmasdale Post Net 412, P/BagE891, Lusaka (Zambia); Department of Pathology and Laboratory Medicine, Emory University, Atlanta, GA (United States); Hunter, Eric, E-mail: eric.hunter2@emory.edu [Emory Vaccine Center, Yerkes National Primate Research Center, 954 Gatewood Road NE, Atlanta, GA 30329 (United States); Department of Pathology and Laboratory Medicine, Emory University, Atlanta, GA (United States)

    2014-11-15

    The high genetic diversity of HIV-1 impedes high throughput, large-scale sequencing and full-length genome cloning by common restriction enzyme based methods. Applying novel methods that employ a high-fidelity polymerase for amplification and an unbiased fusion-based cloning strategy, we have generated several HIV-1 full-length genome infectious molecular clones from an epidemiologically linked transmission pair. These clones represent the transmitted/founder virus and phylogenetically diverse non-transmitted variants from the chronically infected individual's diverse quasispecies near the time of transmission. We demonstrate that, using this approach, PCR-induced mutations in full-length clones derived from their cognate single genome amplicons are rare. Furthermore, all eight non-transmitted genomes tested produced functional virus with a range of infectivities, belying the previous assumption that a majority of circulating viruses in chronic HIV-1 infection are defective. Thus, these methods provide important tools to update protocols in molecular biology that can be universally applied to the study of human viral pathogens. - Highlights: • Our novel methodology demonstrates accurate amplification and cloning of full-length HIV-1 genomes. • A majority of plasma derived HIV variants from a chronically infected individual are infectious. • The transmitted/founder was more infectious than the majority of the variants from the chronically infected donor.

  16. Particle infectivity of HIV-1 full-length genome infectious molecular clones in a subtype C heterosexual transmission pair following high fidelity amplification and unbiased cloning

    International Nuclear Information System (INIS)

    Deymier, Martin J.; Claiborne, Daniel T.; Ende, Zachary; Ratner, Hannah K.; Kilembe, William; Allen, Susan; Hunter, Eric

    2014-01-01

    The high genetic diversity of HIV-1 impedes high throughput, large-scale sequencing and full-length genome cloning by common restriction enzyme based methods. Applying novel methods that employ a high-fidelity polymerase for amplification and an unbiased fusion-based cloning strategy, we have generated several HIV-1 full-length genome infectious molecular clones from an epidemiologically linked transmission pair. These clones represent the transmitted/founder virus and phylogenetically diverse non-transmitted variants from the chronically infected individual's diverse quasispecies near the time of transmission. We demonstrate that, using this approach, PCR-induced mutations in full-length clones derived from their cognate single genome amplicons are rare. Furthermore, all eight non-transmitted genomes tested produced functional virus with a range of infectivities, belying the previous assumption that a majority of circulating viruses in chronic HIV-1 infection are defective. Thus, these methods provide important tools to update protocols in molecular biology that can be universally applied to the study of human viral pathogens. - Highlights: • Our novel methodology demonstrates accurate amplification and cloning of full-length HIV-1 genomes. • A majority of plasma derived HIV variants from a chronically infected individual are infectious. • The transmitted/founder was more infectious than the majority of the variants from the chronically infected donor

  17. An alternative conformation of the gp41 heptad repeat 1 region coiled coil exists in the human immunodeficiency virus (HIV-1) envelope glycoprotein precursor

    International Nuclear Information System (INIS)

    Mische, Claudia C.; Yuan Wen; Strack, Bettina; Craig, Stewart; Farzan, Michael; Sodroski, Joseph

    2005-01-01

    The human immunodeficiency virus (HIV-1) transmembrane envelope glycoprotein, gp41, which mediates virus-cell fusion, exists in at least three different conformations within the trimeric envelope glycoprotein complex. The structures of the prefusogenic and intermediate states are unknown; structures representing the postfusion state have been solved. In the postfusion conformation, three helical heptad repeat 2 (HR2) regions pack in an antiparallel fashion into the hydrophobic grooves on the surface of a triple-helical coiled coil formed by the heptad repeat 1 (HR1) regions. We studied the prefusogenic conformation of gp41 by mutagenic alteration of membrane-anchored and soluble forms of the HIV-1 envelope glycoproteins. Our results indicate that, in the HIV-1 envelope glycoprotein precursor, the gp41 HR1 region is in a conformation distinct from that of a trimeric coiled coil. Thus, the central gp41 coiled coil is formed during the transition of the HIV-1 envelope glycoproteins from the precursor state to the receptor-bound intermediate

  18. Epidemiological trends of HIV-1 infection in blood donors from Catalonia, Spain (2005-2014).

    Science.gov (United States)

    Bes, Marta; Piron, Maria; Casamitjana, Natàlia; Gregori, Josep; Esteban, Juan Ignacio; Ribera, Esteban; Quer, Josep; Puig, Lluís; Sauleda, Sílvia

    2017-09-01

    Human immunodeficiency virus 1 (HIV-1) subtype B is predominant in Spain. However, the recent arrival of immigrant populations has increased the prevalence of non-B subtypes and circulating recombinant forms. The objective of this study was to determine the prevalence of HIV-1 subtypes and transmitted drug-resistance mutations in blood donors from the Catalonian region (northeastern Spain). HIV-1-positive blood donors identified in Catalonia from 2005 to 2014 were included. Demographic variables and risk factors for HIV-1 acquisition were recorded. HIV-1 subtyping was carried out by HIV-1 DNA polymerase region sequencing, and phylogenetic analyses were performed using the neighbor-joining method. During the study period, 2.8 million blood donations were screened, and 214 HIV-1-positive donors were identified, yielding an overall prevalence of 7.7 per 100,000 donations (89% men; mean age, 34 ± 10 years). Most HIV-1-positive donors were native to Spain (81%), and 61% were regular blood donors. When risk factors were known, 62% reportedly were men who had sex with men. HIV-1 subtyping was possible in 176 HIV-1-positive individuals: 143 (81%) had HIV-1 subtype B, and 33 (19%) had non-B subtypes. Most HIV-1 non-B subtypes were circulating recombinant forms (n = 20; 61%). Factors associated with HIV-1 subtype B were male sex (p = 0.007) and men who had sex with men (p HIV-1-positive blood donors in Catalonia. Continuous local epidemiological surveillance is required to implement optimal prevention strategies for controlling transfusion-transmitted HIV and to improve health policies regarding HIV infection. © 2017 AABB.

  19. 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.

  20. 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.

  1. Interdependence of Inhibitor Recognition in HIV-1 Protease.

    Science.gov (United States)

    Paulsen, Janet L; Leidner, Florian; Ragland, Debra A; Kurt Yilmaz, Nese; Schiffer, Celia A

    2017-05-09

    Molecular recognition is a highly interdependent process. Subsite couplings within the active site of proteases are most often revealed through conditional amino acid preferences in substrate recognition. However, the potential effect of these couplings on inhibition and thus inhibitor design is largely unexplored. The present study examines the interdependency of subsites in HIV-1 protease using a focused library of protease inhibitors, to aid in future inhibitor design. Previously a series of darunavir (DRV) analogs was designed to systematically probe the S1' and S2' subsites. Co-crystal structures of these analogs with HIV-1 protease provide the ideal opportunity to probe subsite interdependency. All-atom molecular dynamics simulations starting from these structures were performed and systematically analyzed in terms of atomic fluctuations, intermolecular interactions, and water structure. These analyses reveal that the S1' subsite highly influences other subsites: the extension of the hydrophobic P1' moiety results in 1) reduced van der Waals contacts in the P2' subsite, 2) more variability in the hydrogen bond frequencies with catalytic residues and the flap water, and 3) changes in the occupancy of conserved water sites both proximal and distal to the active site. In addition, one of the monomers in this homodimeric enzyme has atomic fluctuations more highly correlated with DRV than the other monomer. These relationships intricately link the HIV-1 protease subsites and are critical to understanding molecular recognition and inhibitor binding. More broadly, the interdependency of subsite recognition within an active site requires consideration in the selection of chemical moieties in drug design; this strategy is in contrast to what is traditionally done with independent optimization of chemical moieties of an inhibitor.

  2. 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.

  3. 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.

  4. Predicting Bevirimat resistance of HIV-1 from genotype

    Directory of Open Access Journals (Sweden)

    Hoffmann Daniel

    2010-01-01

    Full Text Available Abstract Background Maturation inhibitors are a new class of antiretroviral drugs. Bevirimat (BVM was the first substance in this class of inhibitors entering clinical trials. While the inhibitory function of BVM is well established, the molecular mechanisms of action and resistance are not well understood. It is known that mutations in the regions CS p24/p2 and p2 can cause phenotypic resistance to BVM. We have investigated a set of p24/p2 sequences of HIV-1 of known phenotypic resistance to BVM to test whether BVM resistance can be predicted from sequence, and to identify possible molecular mechanisms of BVM resistance in HIV-1. Results We used artificial neural networks and random forests with different descriptors for the prediction of BVM resistance. Random forests with hydrophobicity as descriptor performed best and classified the sequences with an area under the Receiver Operating Characteristics (ROC curve of 0.93 ± 0.001. For the collected data we find that p2 sequence positions 369 to 376 have the highest impact on resistance, with positions 370 and 372 being particularly important. These findings are in partial agreement with other recent studies. Apart from the complex machine learning models we derived a number of simple rules that predict BVM resistance from sequence with surprising accuracy. According to computational predictions based on the data set used, cleavage sites are usually not shifted by resistance mutations. However, we found that resistance mutations could shorten and weaken the α-helix in p2, which hints at a possible resistance mechanism. Conclusions We found that BVM resistance of HIV-1 can be predicted well from the sequence of the p2 peptide, which may prove useful for personalized therapy if maturation inhibitors reach clinical practice. Results of secondary structure analysis are compatible with a possible route to BVM resistance in which mutations weaken a six-helix bundle discovered in recent experiments

  5. Assessment of phylogenetic sensitivity for reconstructing HIV-1 epidemiological relationships.

    Science.gov (United States)

    Beloukas, Apostolos; Magiorkinis, Emmanouil; Magiorkinis, Gkikas; Zavitsanou, Asimina; Karamitros, Timokratis; Hatzakis, Angelos; Paraskevis, Dimitrios

    2012-06-01

    Phylogenetic analysis has been extensively used as a tool for the reconstruction of epidemiological relations for research or for forensic purposes. It was our objective to assess the sensitivity of different phylogenetic methods and various phylogenetic programs to reconstruct epidemiological links among HIV-1 infected patients that is the probability to reveal a true transmission relationship. Multiple datasets (90) were prepared consisting of HIV-1 sequences in protease (PR) and partial reverse transcriptase (RT) sampled from patients with documented epidemiological relationship (target population), and from unrelated individuals (control population) belonging to the same HIV-1 subtype as the target population. Each dataset varied regarding the number, the geographic origin and the transmission risk groups of the sequences among the control population. Phylogenetic trees were inferred by neighbor-joining (NJ), maximum likelihood heuristics (hML) and Bayesian methods. All clusters of sequences belonging to the target population were correctly reconstructed by NJ and Bayesian methods receiving high bootstrap and posterior probability (PP) support, respectively. On the other hand, TreePuzzle failed to reconstruct or provide significant support for several clusters; high puzzling step support was associated with the inclusion of control sequences from the same geographic area as the target population. In contrary, all clusters were correctly reconstructed by hML as implemented in PhyML 3.0 receiving high bootstrap support. We report that under the conditions of our study, hML using PhyML, NJ and Bayesian methods were the most sensitive for the reconstruction of epidemiological links mostly from sexually infected individuals. Copyright © 2012 Elsevier B.V. All rights reserved.

  6. Heterologous prime-boost regimens with a recombinant chimpanzee adenoviral vector and adjuvanted F4 protein elicit polyfunctional HIV-1-specific T-Cell responses in macaques.

    Science.gov (United States)

    Lorin, Clarisse; Vanloubbeeck, Yannick; Baudart, Sébastien; Ska, Michaël; Bayat, Babak; Brauers, Geoffroy; Clarinval, Géraldine; Donner, Marie-Noëlle; Marchand, Martine; Koutsoukos, Marguerite; Mettens, Pascal; Cohen, Joe; Voss, Gerald

    2015-01-01

    HIV-1-specific CD4+ and CD8+ T lymphocytes are important for HIV-1 replication control. F4/AS01 consists of F4 recombinant fusion protein (containing clade B Gag/p24, Pol/RT, Nef and Gag/p17) formulated in AS01 Adjuvant System, and was shown to induce F4-specific polyfunctional CD4+ T-cell responses in humans. While replication-incompetent recombinant HIV-1/SIV antigen-expressing human adenoviral vectors can elicit high-frequency antigen-specific CD8+ T-cell responses, their use is hampered by widespread pre-existing immunity to human serotypes. Non-human adenovirus serotypes associated with lower prevalence may offer an alternative strategy. We evaluated the immunogenicity of AdC7-GRN ('A'), a recombinant chimpanzee adenovirus type 7 vector expressing clade B Gag, RT and Nef, and F4/AS01 ('P'), when delivered intramuscularly in homologous (PP or AA) and heterologous (AAPP or PPAA) prime-boost regimens, in macaques and mice. Vaccine-induced HIV-1-antigen-specific T cells in peripheral blood (macaques), liver, spleen, and intestinal and genital mucosa (mice) were characterized by intracellular cytokine staining. Vaccine-specific IgG antibodies (macaques) were detected using ELISA. In macaques, only the heterologous prime-boost regimens induced polyfunctional, persistent and balanced CD4+ and CD8+ T-cell responses specific to each HIV-1 vaccine antigen. AdC7-GRN priming increased the polyfunctionality of F4/AS01-induced CD4+ T cells. Approximately 50% of AdC7-GRN-induced memory CD8+ T cells exhibited an effector-memory phenotype. HIV-1-specific antibodies were detected with each regimen. In mice, antigen-specific CD4+ and CD8+ T-cell responses were detected in the mucosal and systemic anatomical compartments assessed. When administered in heterologous prime-boost regimens, AdC7-GRN and F4/AS01 candidate vaccines acted complementarily in inducing potent and persistent peripheral blood HIV-1-specific CD4+ and CD8+ T-cell responses and antibodies in macaques. Besides

  7. Optical delivery of ARV drugs into HIV-1 permissive cells

    CSIR Research Space (South Africa)

    Khanyile, T

    2013-10-01

    Full Text Available - “Ongoing declines in AIDS incidence and deaths in developed nations, primarily due to widespread use of HAART” (Roger J Pomerantz and David L Horn) AIDS-related deaths, 1995–2011 (World Health Organisation, 2012) Sub-Saharan Africa region: 23....5 mil living with HIV-1 N o . o f p e o p le in m ill io n s 0 500 000 1 000 000 1 500 000 2 000 000 2 500 000 3 000 000 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 Without antiretroviral therapy...

  8. Prediction of the Secondary Structure of HIV-1 gp120

    DEFF Research Database (Denmark)

    Hansen, Jan; Lund, Ole; Nielsen, Jens O.

    1996-01-01

    Fourier transform infrared spectroscopy. The predicted secondary structure of gp120 compared well with data from NMR analysis of synthetic peptides from the V3 loop and the C4 region. As a first step towards modeling the tertiary structure of gp120, the predicted secondary structure may guide the design......The secondary structure of HIV-1 gp120 was predicted using multiple alignment and a combination of two independent methods based on neural network and nearest-neighbor algorithms. The methods agreed on the secondary structure for 80% of the residues in BH10 gp120. Six helices were predicted in HIV...

  9. Progress and perspectives on HIV-1 microbicide development

    CSIR Research Space (South Africa)

    Alexandre, KB

    2016-10-01

    Full Text Available of in- fected women compared to men. This can be explained by women socio-economic dependence on men, domestic violence, high in- cidence of rape, cultural norms and women inability to negotiate safe sex practices, such as the use of condom... this latter found a 50% increase in the risk of con- tracting HIV-1 in the study group (Statement on results of pro- ducts containing N-9 from the CDC, 2000). The risk was even higher in womenwho reported a reduced use of condom. This was believed to be due...

  10. 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

  11. 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.

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

    Science.gov (United States)

    Bomsel, Morgane; Ganor, Yonatan

    2017-12-01

    The neuroimmune dialogue between peripheral neurons and Langerhans cells (LCs) within mucosal epithelia protects against incoming pathogens. LCs rapidly internalize human immunodeficiency virus type 1 (HIV-1) upon its sexual transmission and then trans -infect CD4 + T cells. We recently found that the neuropeptide calcitonin gene-related peptide (CGRP), secreted mucosally from peripheral neurons, inhibits LC-mediated HIV-1 trans -infection. In this study, we investigated the mechanism of CGRP-induced inhibition, focusing on HIV-1 degradation in LCs and its interplay with trans -infection. We first show that HIV-1 degradation occurs in endolysosomes in untreated LCs, and functionally blocking such degradation with lysosomotropic agents results in increased trans -infection. We demonstrate that CGRP acts via its cognate receptor and at a viral postentry step to induce faster HIV-1 degradation, but without affecting the kinetics of endolysosomal degradation. We reveal that unexpectedly, CGRP shifts HIV-1 degradation from endolysosomes toward the proteasome, providing the first evidence for functional HIV-1 proteasomal degradation in LCs. Such efficient proteasomal degradation significantly inhibits the first phase of trans -infection, and proteasomal, but not endolysosomal, inhibitors abrogate CGRP-induced inhibition. Together, our results establish that CGRP controls the HIV-1 degradation mode in LCs. The presence of endogenous CGRP within innervated mucosal tissues, especially during the sexual response, to which CGRP contributes, suggests that HIV-1 proteasomal degradation predominates in vivo Hence, proteasomal, rather than endolysosomal, HIV-1 degradation in LCs should be enhanced clinically to effectively restrict HIV-1 trans -infection. IMPORTANCE During sexual transmission, HIV-1 is internalized and degraded in LCs, the resident antigen-presenting cells in mucosal epithelia. Yet during trans -infection, infectious virions escaping degradation are transferred

  13. Appreciating HIV-1 diversity: subtypic differences in ENV

    Energy Technology Data Exchange (ETDEWEB)

    Gnanakaran, S [Los Alamos National Laboratory; Shen, Tongye [Los Alamos National Laboratory; Lynch, Rebecca M [NON LANL; Derdeyn, Cynthia A [NON LANL

    2008-01-01

    Human immunodeficiency virus type 1 (HIV-1) group M is responsible for the current AIDS pandemic and exhibits exceedingly high levels of viral genetic diversity around the world, necessitating categorization of viruses into distinct lineages, or subtypes. These subtypes can differ by around 35% in the envelope (Env) glycoproteins of the virus, which are displayed on the surface of the virion and are targets for both neutralizing antibody and cell-mediated immune responses. This diversity reflects the remarkable ability of the virus to adapt to selective pressures, the bulk of which is applied by the host immune response, and represents a serious obstacle for developing an effective vaccine with broad coverage. Thus, it is important to understand the underlying biological consequences of inter-subtype diversity. Recent studies have revealed that the HIV-1 subtypes exhibit phenotypic differences that result from subtle differences in Env structure, particularly within the highly immunogenic V3 domain, which participates directly in viral entry. This review will therefore explore current research that describes subtypic differences in Env at the genetic and phenotypic level, focusing in particular on V3, and highlighting recent discoveries about the unique features of subtype C Env, which is the most prevalent subtype globally.

  14. Large-scale functional purification of recombinant HIV-1 capsid.

    Directory of Open Access Journals (Sweden)

    Magdeleine Hung

    Full Text Available During human immunodeficiency virus type-1 (HIV-1 virion maturation, capsid proteins undergo a major rearrangement to form a conical core that protects the viral nucleoprotein complexes. Mutations in the capsid sequence that alter the stability of the capsid core are deleterious to viral infectivity and replication. Recently, capsid assembly has become an attractive target for the development of a new generation of anti-retroviral agents. Drug screening efforts and subsequent structural and mechanistic studies require gram quantities of active, homogeneous and pure protein. Conventional means of laboratory purification of Escherichia coli expressed recombinant capsid protein rely on column chromatography steps that are not amenable to large-scale production. Here we present a function-based purification of wild-type and quadruple mutant capsid proteins, which relies on the inherent propensity of capsid protein to polymerize and depolymerize. This method does not require the packing of sizable chromatography columns and can generate double-digit gram quantities of functionally and biochemically well-behaved proteins with greater than 98% purity. We have used the purified capsid protein to characterize two known assembly inhibitors in our in-house developed polymerization assay and to measure their binding affinities. Our capsid purification procedure provides a robust method for purifying large quantities of a key protein in the HIV-1 life cycle, facilitating identification of the next generation anti-HIV agents.

  15. Cellular Antiviral Factors that Target Particle Infectivity of HIV-1.

    Science.gov (United States)

    Goffinet, Christine

    2016-01-01

    In the past decade, the identification and characterization of antiviral genes with the ability to interfere with virus replication has established cell-intrinsic innate immunity as a third line of antiviral defense in addition to adaptive and classical innate immunity. Understanding how cellular factors have evolved to inhibit HIV-1 reveals particularly vulnerable points of the viral replication cycle. Many, but not all, antiviral proteins share type I interferon-upregulated expression and sensitivity to viral counteraction or evasion measures. Whereas well-established restriction factors interfere with early post-entry steps and release of HIV-1, recent research has revealed a diverse set of proteins that reduce the infectious quality of released particles using individual, to date poorly understood modes of action. These include induction of paucity of mature glycoproteins in nascent virions or self-incorporation into the virus particle, resulting in poor infectiousness of the virion and impaired spread of the infection. A better understanding of these newly discovered antiviral factors may open new avenues towards the design of drugs that repress the spread of viruses whose genomes have already integrated.

  16. Effects of HIV-1 on Cognition in Humanized NSG Mice

    Science.gov (United States)

    Akhter, Sidra Pervez

    Host species specificity of human immunodeficiency virus (HIV) creates a challenge to study the pathology, diagnostic tools, and therapeutic agents. The closely related simian immunodeficiency virus and studies of neurocognitive impairments on transgenic animals expressing partial viral genome have significant limitations. The humanized mice model provides a small animal system in which a human immune system can be engrafted and immunopathobiology of HIV-1 infection can be studied. However, features of HIV-associated neurocognitive disorders (HAND) were not evaluated in this model. Open field activity test was selected to characterize behavior of original strain NOD/scid-IL-2Rgammac null (NSG) mice, effects of engraftment of human CD34+ hematopoietic stem cells (HSCs) and functional human immune system (huNSG), and finally, investigate the behavior changes induced by chronic HIV-1 infection. Long-term infected HuNSG mice showed the loss of working memory and increased anxiety in the open field. Additionally, these animals were utilized for evaluation of central nervous system metabolic and structural changes. Detected behavioral abnormalities are correlated with obtained neuroimaging and histological abnormalities published.

  17. The evolutionary rate dynamically tracks changes in HIV-1 epidemics

    Energy Technology Data Exchange (ETDEWEB)

    Maljkovic-berry, Irina [Los Alamos National Laboratory; Athreya, Gayathri [Los Alamos National Laboratory; Daniels, Marcus [Los Alamos National Laboratory; Bruno, William [Los Alamos National Laboratory; Korber, Bette [Los Alamos National Laboratory; Kuiken, Carla [Los Alamos National Laboratory; Ribeiro, Ruy M [Los Alamos National Laboratory

    2009-01-01

    Large-sequence datasets provide an opportunity to investigate the dynamics of pathogen epidemics. Thus, a fast method to estimate the evolutionary rate from large and numerous phylogenetic trees becomes necessary. Based on minimizing tip height variances, we optimize the root in a given phylogenetic tree to estimate the most homogenous evolutionary rate between samples from at least two different time points. Simulations showed that the method had no bias in the estimation of evolutionary rates and that it was robust to tree rooting and topological errors. We show that the evolutionary rates of HIV-1 subtype B and C epidemics have changed over time, with the rate of evolution inversely correlated to the rate of virus spread. For subtype B, the evolutionary rate slowed down and tracked the start of the HAART era in 1996. Subtype C in Ethiopia showed an increase in the evolutionary rate when the prevalence increase markedly slowed down in 1995. Thus, we show that the evolutionary rate of HIV-1 on the population level dynamically tracks epidemic events.

  18. 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

  19. HIV-1 pre-mRNA commitment to Rev mediated export through PSF and Matrin 3

    International Nuclear Information System (INIS)

    Kula, Anna; Gharu, Lavina; Marcello, Alessandro

    2013-01-01

    Human immunodeficiency virus gene expression and replication are regulated at several levels. Incompletely spliced viral RNAs and full-length genomic RNA contain the RRE element and are bound by the viral trans-acting protein Rev to be transported out of the nucleus. Previously we found that the nuclear matrix protein MATR3 was a cofactor of Rev-mediated RNA export. Here we show that the pleiotropic protein PSF binds viral RNA and is associated with MATR3. PSF is involved in the maintenance of a pool of RNA available for Rev activity. However, while Rev and PSF bind the viral pre-mRNA at the site of viral transcription, MATR3 interacts at a subsequent step. We propose that PSF and MATR3 define a novel pathway for RRE-containing HIV-1 RNAs that is hijacked by the viral Rev protein.

  20. The major genetic determinants of HIV-1 control affect HLA class I peptide presentation.

    Science.gov (United States)

    Pereyra, Florencia; Jia, Xiaoming; McLaren, Paul J; Telenti, Amalio; de Bakker, Paul I W; Walker, Bruce D; Ripke, Stephan; Brumme, Chanson J; Pulit, Sara L; Carrington, Mary; Kadie, Carl M; Carlson, Jonathan M; Heckerman, David; Graham, Robert R; Plenge, Robert M; Deeks, Steven G; Gianniny, Lauren; Crawford, Gabriel; Sullivan, Jordan; Gonzalez, Elena; Davies, Leela; Camargo, Amy; Moore, Jamie M; Beattie, Nicole; Gupta, Supriya; Crenshaw, Andrew; Burtt, Noël P; Guiducci, Candace; Gupta, Namrata; Gao, Xiaojiang; Qi, Ying; Yuki, Yuko; Piechocka-Trocha, Alicja; Cutrell, Emily; Rosenberg, Rachel; Moss, Kristin L; Lemay, Paul; O'Leary, Jessica; Schaefer, Todd; Verma, Pranshu; Toth, Ildiko; Block, Brian; Baker, Brett; Rothchild, Alissa; Lian, Jeffrey; Proudfoot, Jacqueline; Alvino, Donna Marie L; Vine, Seanna; Addo, Marylyn M; Allen, Todd M; Altfeld, Marcus; Henn, Matthew R; Le Gall, Sylvie; Streeck, Hendrik; Haas, David W; Kuritzkes, Daniel R; Robbins, Gregory K; Shafer, Robert W; Gulick, Roy M; Shikuma, Cecilia M; Haubrich, Richard; Riddler, Sharon; Sax, Paul E; Daar, Eric S; Ribaudo, Heather J; Agan, Brian; Agarwal, Shanu; Ahern, Richard L; Allen, Brady L; Altidor, Sherly; Altschuler, Eric L; Ambardar, Sujata; Anastos, Kathryn; Anderson, Ben; Anderson, Val; Andrady, Ushan; Antoniskis, Diana; Bangsberg, David; Barbaro, Daniel; Barrie, William; Bartczak, J; Barton, Simon; Basden, Patricia; Basgoz, Nesli; Bazner, Suzane; Bellos, Nicholaos C; Benson, Anne M; Berger, Judith; Bernard, Nicole F; Bernard, Annette M; Birch, Christopher; Bodner, Stanley J; Bolan, Robert K; Boudreaux, Emilie T; Bradley, Meg; Braun, James F; Brndjar, Jon E; Brown, Stephen J; Brown, Katherine; Brown, Sheldon T; Burack, Jedidiah; Bush, Larry M; Cafaro, Virginia; Campbell, Omobolaji; Campbell, John; Carlson, Robert H; Carmichael, J Kevin; Casey, Kathleen K; Cavacuiti, Chris; Celestin, Gregory; Chambers, Steven T; Chez, Nancy; Chirch, Lisa M; Cimoch, Paul J; Cohen, Daniel; Cohn, Lillian E; Conway, Brian; Cooper, David A; Cornelson, Brian; Cox, David T; Cristofano, Michael V; Cuchural, George; Czartoski, Julie L; Dahman, Joseph M; Daly, Jennifer S; Davis, Benjamin T; Davis, Kristine; Davod, Sheila M; DeJesus, Edwin; Dietz, Craig A; Dunham, Eleanor; Dunn, Michael E; Ellerin, Todd B; Eron, Joseph J; Fangman, John J W; Farel, Claire E; Ferlazzo, Helen; Fidler, Sarah; Fleenor-Ford, Anita; Frankel, Renee; Freedberg, Kenneth A; French, Neel K; Fuchs, Jonathan D; Fuller, Jon D; Gaberman, Jonna; Gallant, Joel E; Gandhi, Rajesh T; Garcia, Efrain; Garmon, Donald; Gathe, Joseph C; Gaultier, Cyril R; Gebre, Wondwoosen; Gilman, Frank D; Gilson, Ian; Goepfert, Paul A; Gottlieb, Michael S; Goulston, Claudia; Groger, Richard K; Gurley, T Douglas; Haber, Stuart; Hardwicke, Robin; Hardy, W David; Harrigan, P Richard; Hawkins, Trevor N; Heath, Sonya; Hecht, Frederick M; Henry, W Keith; Hladek, Melissa; Hoffman, Robert P; Horton, James M; Hsu, Ricky K; Huhn, Gregory D; Hunt, Peter; Hupert, Mark J; Illeman, Mark L; Jaeger, Hans; Jellinger, Robert M; John, Mina; Johnson, Jennifer A; Johnson, Kristin L; Johnson, Heather; Johnson, Kay; Joly, Jennifer; Jordan, Wilbert C; Kauffman, Carol A; Khanlou, Homayoon; Killian, Robert K; Kim, Arthur Y; Kim, David D; Kinder, Clifford A; Kirchner, Jeffrey T; Kogelman, Laura; Kojic, Erna Milunka; Korthuis, P Todd; Kurisu, Wayne; Kwon, Douglas S; LaMar, Melissa; Lampiris, Harry; Lanzafame, Massimiliano; Lederman, Michael M; Lee, David M; Lee, Jean M L; Lee, Marah J; Lee, Edward T Y; Lemoine, Janice; Levy, Jay A; Llibre, Josep M; Liguori, Michael A; Little, Susan J; Liu, Anne Y; Lopez, Alvaro J; Loutfy, Mono R; Loy, Dawn; Mohammed, Debbie Y; Man, Alan; Mansour, Michael K; Marconi, Vincent C; Markowitz, Martin; Marques, Rui; Martin, Jeffrey N; Martin, Harold L; Mayer, Kenneth Hugh; McElrath, M Juliana; McGhee, Theresa A; McGovern, Barbara H; McGowan, Katherine; McIntyre, Dawn; Mcleod, Gavin X; Menezes, Prema; Mesa, Greg; Metroka, Craig E; Meyer-Olson, Dirk; Miller, Andy O; Montgomery, Kate; Mounzer, Karam C; Nagami, Ellen H; Nagin, Iris; Nahass, Ronald G; Nelson, Margret O; Nielsen, Craig; Norene, David L; O'Connor, David H; Ojikutu, Bisola O; Okulicz, Jason; Oladehin, Olakunle O; Oldfield, Edward C; Olender, Susan A; Ostrowski, Mario; Owen, William F; Pae, Eunice; Parsonnet, Jeffrey; Pavlatos, Andrew M; Perlmutter, Aaron M; Pierce, Michael N; Pincus, Jonathan M; Pisani, Leandro; Price, Lawrence Jay; Proia, Laurie; Prokesch, Richard C; Pujet, Heather Calderon; Ramgopal, Moti; Rathod, Almas; Rausch, Michael; Ravishankar, J; Rhame, Frank S; Richards, Constance Shamuyarira; Richman, Douglas D; Rodes, Berta; Rodriguez, Milagros; Rose, Richard C; Rosenberg, Eric S; Rosenthal, Daniel; Ross, Polly E; Rubin, David S; Rumbaugh, Elease; Saenz, Luis; Salvaggio, Michelle R; Sanchez, William C; Sanjana, Veeraf M; Santiago, Steven; Schmidt, Wolfgang; Schuitemaker, Hanneke; Sestak, Philip M; Shalit, Peter; Shay, William; Shirvani, Vivian N; Silebi, Vanessa I; Sizemore, James M; Skolnik, Paul R; Sokol-Anderson, Marcia; Sosman, James M; Stabile, Paul; Stapleton, Jack T; Starrett, Sheree; Stein, Francine; Stellbrink, Hans-Jurgen; Sterman, F Lisa; Stone, Valerie E; Stone, David R; Tambussi, Giuseppe; Taplitz, Randy A; Tedaldi, Ellen M; Telenti, Amalio; Theisen, William; Torres, Richard; Tosiello, Lorraine; Tremblay, Cecile; Tribble, Marc A; Trinh, Phuong D; Tsao, Alice; Ueda, Peggy; Vaccaro, Anthony; Valadas, Emilia; Vanig, Thanes J; Vecino, Isabel; Vega, Vilma M; Veikley, Wenoah; Wade, Barbara H; Walworth, Charles; Wanidworanun, Chingchai; Ward, Douglas J; Warner, Daniel A; Weber, Robert D; Webster, Duncan; Weis, Steve; Wheeler, David A; White, David J; Wilkins, Ed; Winston, Alan; Wlodaver, Clifford G; van't Wout, Angelique; Wright, David P; Yang, Otto O; Yurdin, David L; Zabukovic, Brandon W; Zachary, Kimon C; Zeeman, Beth; Zhao, Meng

    2010-12-10

    Infectious and inflammatory diseases have repeatedly shown strong genetic associations within the major histocompatibility complex (MHC); however, the basis for these associations remains elusive. To define host genetic effects on the outcome of a chronic viral infection, we performed genome-wide association analysis in a multiethnic cohort of HIV-1 controllers and progressors, and we analyzed the effects of individual amino acids within the classical human leukocyte antigen (HLA) proteins. We identified >300 genome-wide significant single-nucleotide polymorphisms (SNPs) within the MHC and none elsewhere. Specific amino acids in the HLA-B peptide binding groove, as well as an independent HLA-C effect, explain the SNP associations and reconcile both protective and risk HLA alleles. These results implicate the nature of the HLA-viral peptide interaction as the major factor modulating durable control of HIV infection.

  1. The Major Genetic Determinants of HIV-1 Control Affect HLA Class I Peptide Presentation

    Science.gov (United States)

    Pereyra, Florencia; Jia, Xiaoming; McLaren, Paul J.; Telenti, Amalio; de Bakker, Paul I.W.; Walker, Bruce D.; Jia, Xiaoming; McLaren, Paul J.; Ripke, Stephan; Brumme, Chanson J.; Pulit, Sara L.; Telenti, Amalio; Carrington, Mary; Kadie, Carl M.; Carlson, Jonathan M.; Heckerman, David; de Bakker, Paul I.W.; Pereyra, Florencia; de Bakker, Paul I.W.; Graham, Robert R.; Plenge, Robert M.; Deeks, Steven G.; Walker, Bruce D.; Gianniny, Lauren; Crawford, Gabriel; Sullivan, Jordan; Gonzalez, Elena; Davies, Leela; Camargo, Amy; Moore, Jamie M.; Beattie, Nicole; Gupta, Supriya; Crenshaw, Andrew; Burtt, Noël P.; Guiducci, Candace; Gupta, Namrata; Carrington, Mary; Gao, Xiaojiang; Qi, Ying; Yuki, Yuko; Pereyra, Florencia; Piechocka-Trocha, Alicja; Cutrell, Emily; Rosenberg, Rachel; Moss, Kristin L.; Lemay, Paul; O’Leary, Jessica; Schaefer, Todd; Verma, Pranshu; Toth, Ildiko; Block, Brian; Baker, Brett; Rothchild, Alissa; Lian, Jeffrey; Proudfoot, Jacqueline; Alvino, Donna Marie L.; Vine, Seanna; Addo, Marylyn M.; Allen, Todd M.; Altfeld, Marcus; Henn, Matthew R.; Le Gall, Sylvie; Streeck, Hendrik; Walker, Bruce D.; Haas, David W.; Kuritzkes, Daniel R.; Robbins, Gregory K.; Shafer, Robert W.; Gulick, Roy M.; Shikuma, Cecilia M.; Haubrich, Richard; Riddler, Sharon; Sax, Paul E.; Daar, Eric S.; Ribaudo, Heather J.; Agan, Brian; Agarwal, Shanu; Ahern, Richard L.; Allen, Brady L.; Altidor, Sherly; Altschuler, Eric L.; Ambardar, Sujata; Anastos, Kathryn; Anderson, Ben; Anderson, Val; Andrady, Ushan; Antoniskis, Diana; Bangsberg, David; Barbaro, Daniel; Barrie, William; Bartczak, J.; Barton, Simon; Basden, Patricia; Basgoz, Nesli; Bazner, Suzane; Bellos, Nicholaos C.; Benson, Anne M.; Berger, Judith; Bernard, Nicole F.; Bernard, Annette M.; Birch, Christopher; Bodner, Stanley J.; Bolan, Robert K.; Boudreaux, Emilie T.; Bradley, Meg; Braun, James F.; Brndjar, Jon E.; Brown, Stephen J.; Brown, Katherine; Brown, Sheldon T.; Burack, Jedidiah; Bush, Larry M.; Cafaro, Virginia; Campbell, Omobolaji; Campbell, John; Carlson, Robert H.; Carmichael, J. Kevin; Casey, Kathleen K.; Cavacuiti, Chris; Celestin, Gregory; Chambers, Steven T.; Chez, Nancy; Chirch, Lisa M.; Cimoch, Paul J.; Cohen, Daniel; Cohn, Lillian E.; Conway, Brian; Cooper, David A.; Cornelson, Brian; Cox, David T.; Cristofano, Michael V.; Cuchural, George; Czartoski, Julie L.; Dahman, Joseph M.; Daly, Jennifer S.; Davis, Benjamin T.; Davis, Kristine; Davod, Sheila M.; Deeks, Steven G.; DeJesus, Edwin; Dietz, Craig A.; Dunham, Eleanor; Dunn, Michael E.; Ellerin, Todd B.; Eron, Joseph J.; Fangman, John J.W.; Farel, Claire E.; Ferlazzo, Helen; Fidler, Sarah; Fleenor-Ford, Anita; Frankel, Renee; Freedberg, Kenneth A.; French, Neel K.; Fuchs, Jonathan D.; Fuller, Jon D.; Gaberman, Jonna; Gallant, Joel E.; Gandhi, Rajesh T.; Garcia, Efrain; Garmon, Donald; Gathe, Joseph C.; Gaultier, Cyril R.; Gebre, Wondwoosen; Gilman, Frank D.; Gilson, Ian; Goepfert, Paul A.; Gottlieb, Michael S.; Goulston, Claudia; Groger, Richard K.; Gurley, T. Douglas; Haber, Stuart; Hardwicke, Robin; Hardy, W. David; Harrigan, P. Richard; Hawkins, Trevor N.; Heath, Sonya; Hecht, Frederick M.; Henry, W. Keith; Hladek, Melissa; Hoffman, Robert P.; Horton, James M.; Hsu, Ricky K.; Huhn, Gregory D.; Hunt, Peter; Hupert, Mark J.; Illeman, Mark L.; Jaeger, Hans; Jellinger, Robert M.; John, Mina; Johnson, Jennifer A.; Johnson, Kristin L.; Johnson, Heather; Johnson, Kay; Joly, Jennifer; Jordan, Wilbert C.; Kauffman, Carol A.; Khanlou, Homayoon; Killian, Robert K.; Kim, Arthur Y.; Kim, David D.; Kinder, Clifford A.; Kirchner, Jeffrey T.; Kogelman, Laura; Kojic, Erna Milunka; Korthuis, P. Todd; Kurisu, Wayne; Kwon, Douglas S.; LaMar, Melissa; Lampiris, Harry; Lanzafame, Massimiliano; Lederman, Michael M.; Lee, David M.; Lee, Jean M.L.; Lee, Marah J.; Lee, Edward T.Y.; Lemoine, Janice; Levy, Jay A.; Llibre, Josep M.; Liguori, Michael A.; Little, Susan J.; Liu, Anne Y.; Lopez, Alvaro J.; Loutfy, Mono R.; Loy, Dawn; Mohammed, Debbie Y.; Man, Alan; Mansour, Michael K.; Marconi, Vincent C.; Markowitz, Martin; Marques, Rui; Martin, Jeffrey N.; Martin, Harold L.; Mayer, Kenneth Hugh; McElrath, M. Juliana; McGhee, Theresa A.; McGovern, Barbara H.; McGowan, Katherine; McIntyre, Dawn; Mcleod, Gavin X.; Menezes, Prema; Mesa, Greg; Metroka, Craig E.; Meyer-Olson, Dirk; Miller, Andy O.; Montgomery, Kate; Mounzer, Karam C.; Nagami, Ellen H.; Nagin, Iris; Nahass, Ronald G.; Nelson, Margret O.; Nielsen, Craig; Norene, David L.; O’Connor, David H.; Ojikutu, Bisola O.; Okulicz, Jason; Oladehin, Olakunle O.; Oldfield, Edward C.; Olender, Susan A.; Ostrowski, Mario; Owen, William F.; Pae, Eunice; Parsonnet, Jeffrey; Pavlatos, Andrew M.; Perlmutter, Aaron M.; Pierce, Michael N.; Pincus, Jonathan M.; Pisani, Leandro; Price, Lawrence Jay; Proia, Laurie; Prokesch, Richard C.; Pujet, Heather Calderon; Ramgopal, Moti; Rathod, Almas; Rausch, Michael; Ravishankar, J.; Rhame, Frank S.; Richards, Constance Shamuyarira; Richman, Douglas D.; Robbins, Gregory K.; Rodes, Berta; Rodriguez, Milagros; Rose, Richard C.; Rosenberg, Eric S.; Rosenthal, Daniel; Ross, Polly E.; Rubin, David S.; Rumbaugh, Elease; Saenz, Luis; Salvaggio, Michelle R.; Sanchez, William C.; Sanjana, Veeraf M.; Santiago, Steven; Schmidt, Wolfgang; Schuitemaker, Hanneke; Sestak, Philip M.; Shalit, Peter; Shay, William; Shirvani, Vivian N.; Silebi, Vanessa I.; Sizemore, James M.; Skolnik, Paul R.; Sokol-Anderson, Marcia; Sosman, James M.; Stabile, Paul; Stapleton, Jack T.; Starrett, Sheree; Stein, Francine; Stellbrink, Hans-Jurgen; Sterman, F. Lisa; Stone, Valerie E.; Stone, David R.; Tambussi, Giuseppe; Taplitz, Randy A.; Tedaldi, Ellen M.; Telenti, Amalio; Theisen, William; Torres, Richard; Tosiello, Lorraine; Tremblay, Cecile; Tribble, Marc A.; Trinh, Phuong D.; Tsao, Alice; Ueda, Peggy; Vaccaro, Anthony; Valadas, Emilia; Vanig, Thanes J.; Vecino, Isabel; Vega, Vilma M.; Veikley, Wenoah; Wade, Barbara H.; Walworth, Charles; Wanidworanun, Chingchai; Ward, Douglas J.; Warner, Daniel A.; Weber, Robert D.; Webster, Duncan; Weis, Steve; Wheeler, David A.; White, David J.; Wilkins, Ed; Winston, Alan; Wlodaver, Clifford G.; Wout, Angelique van’t; Wright, David P.; Yang, Otto O.; Yurdin, David L.; Zabukovic, Brandon W.; Zachary, Kimon C.; Zeeman, Beth; Zhao, Meng

    2011-01-01

    Infectious and inflammatory diseases have repeatedly shown strong genetic associations within the major histocompatibility complex (MHC); however, the basis for these associations remains elusive. To define host genetic effects on the outcome of a chronic viral infection, we performed genome-wide association analysis in a multiethnic cohort of HIV-1 controllers and progressors, and we analyzed the effects of individual amino acids within the classical human leukocyte antigen (HLA) proteins. We identified >300 genome-wide significant single-nucleotide polymorphisms (SNPs) within the MHC and none elsewhere. Specific amino acids in the HLA-B peptide binding groove, as well as an independent HLA-C effect, explain the SNP associations and reconcile both protective and risk HLA alleles. These results implicate the nature of the HLA–viral peptide interaction as the major factor modulating durable control of HIV infection. PMID:21051598

  2. Puberty in perinatal HIV-1 infection: a multicentre longitudinal study of 212 children.

    Science.gov (United States)

    de Martino, M; Tovo, P A; Galli, L; Gabiano, C; Chiarelli, F; Zappa, M; Gattinara, G C; Bassetti, D; Giacomet, V; Chiappini, E; Duse, M; Garetto, S; Caselli, D

    2001-08-17

    To define age at entry into Tanner stages in children with perinatal HIV-1 infection. Multicentre longitudinal study including 212 perinatally HIV-1-infected children (107 girls and 105 boys) followed-up during puberty (from 8 and 9 years onwards in girls and boys, respectively). Healthy children (843 girls and 821 boys) provided reference percentiles. P2 or B2 stages in girls and P2 or G2 stages in boys defined onset of puberty. The cumulative probability [95% confidence limit (CI)] of entry into each stage at different ages was estimated by the Kaplan-Meier product-limit method; differences were evaluated by log rank test. Relationships were tested using the Spearman's rank correlation coefficient. Ages of girls [years (95%CI)] at P2 [12.9 (12.6-13.2)], P3 [13.4 (13.0-13.8)], P4 [14.6 (14.0-15.2)], B2 [12.7 (12.2-13.2)], B3 [13.3 (12.8-14.0)] and B4 [14.6 (14.0-15.2)] stages were > 97th percentile (> or = 21 month delay) of controls. Ages of boys [years (95%CI)] at P2 [12.6 (12.1-13.1)], P3 [13.9 (13.4-14.4)], P4 [14.9 (14.2-15.6)], G2 [12.1 (11.5-12.7)], G3 [13.6 (13.1-14.1)] and G4 [14.9 (14.1-15.7)] stages were at the 75-97th percentiles (< or = 15 month delay). Age at onset of puberty was not related to clinical and immunological condition, antiretroviral treatment, weigh for height and age at onset of severe disease or immune suppression. Perinatal HIV-1 infection interferes with sexual maturation. The mechanisms by which this occurs should be elucidated and intervention strategies designed. Intervention could save much psychological distress, since associated linear growth failure can exacerbate adolescents' feelings of being different and unwell.

  3. Higher Desolvation Energy Reduces Molecular Recognition in Multi-Drug Resistant HIV-1 Protease

    Directory of Open Access Journals (Sweden)

    Ladislau C. Kovari

    2012-05-01

    Full Text Available Designing HIV-1 protease inhibitors that overcome drug-resistance is still a challenging task. In this study, four clinical isolates of multi-drug resistant HIV-1 proteases that exhibit resistance to all the US FDA-approved HIV-1 protease inhibitors and also reduce the substrate recognition ability were examined. A multi-drug resistant HIV-1 protease isolate, MDR 769, was co-crystallized with the p2/NC substrate and the mutated CA/p2 substrate, CA/p2 P1’F. Both substrates display different levels of molecular recognition by the wild-type and multi-drug resistant HIV-1 protease. From the crystal structures, only limited differences can be identified between the wild-type and multi-drug resistant protease. Therefore, a wild-type HIV-1 protease and four multi-drug resistant HIV-1 proteases in complex with the two peptides were modeled based on the crystal structures and examined during a 10 ns-molecular dynamics simulation. The simulation results reveal that the multi-drug resistant HIV-1 proteases require higher desolvation energy to form complexes with the peptides. This result suggests that the desolvation of the HIV-1 protease active site is an important step of protease-ligand complex formation as well as drug resistance. Therefore, desolvation energy could be considered as a parameter in the evaluation of future HIV-1 protease inhibitor candidates.

  4. 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

  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 (0.1–1 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. New sensitive and specific assay for human immunodeficiency virus antibodies using labeled recombinant fusion protein and time-resolved fluoroimmunoassay.

    OpenAIRE

    Siitari, H; Turunen, P; Schrimsher, J; Nunn, M

    1990-01-01

    A new, rapid method for the detection of human immunodeficiency virus type 1 (HIV-1) antibody by time-resolved fluoroimmunoassay (TR-FIA) was developed. In this assay format, microtitration strips were coated with a recombinant fusion protein, and the same protein was labeled with europium and added into the wells simultaneously with the test specimens. The recombinant fusion protein contained the HIV-1 p24 gag protein sequence that carried an insertion, near the carboxyl terminus, of a 23-am...

  7. 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.

  8. Meticulous plasma isolation is essential to avoid false low-level viraemia in Roche Cobas HIV-1 viral load assays.

    Science.gov (United States)

    Mortier, Virginie; Vancoillie, Leen; Dauwe, Kenny; Staelens, Delfien; Demecheleer, Els; Schauvliege, Marlies; Dinakis, Sylvie; Van Maerken, Tom; Dessilly, Géraldine; Ruelle, Jean; Verhofstede, Chris

    2017-10-24

    Pre-analytical sample processing is often overlooked as a potential cause of inaccurate assay results. Here we demonstrate how plasma, extracted from standard EDTA-containing blood collection tubes, may contain traces of blood cells consequently resulting in a false low-level HIV-1 viral load when using Roche Cobas HIV-1 assays. The presence of human DNA in Roche Cobas 4800 RNA extracts and in RNA extracts from the Abbott HIV-1 RealTime assay was assessed by quantifying the human albumin gene by means of quantitative PCR. RNA was extracted from plasma samples before and after an additional centrifugation and tested for viral load and DNA contamination. The relation between total DNA content and viral load was defined. Elevated concentrations of genomic DNA were detected in 28 out of 100 Cobas 4800 extracts and were significantly more frequent in samples processed outside of the AIDS Reference Laboratory. An association between genomic DNA presence and spurious low-level viraemia results was demonstrated. Supplementary centrifugation of plasma before RNA extraction eliminated the contamination and the false viraemia. Plasma isolated from standard EDTA-containing blood collection tubes may contain traces of HIV DNA leading to false viral load results above the clinical cutoff. Supplementary centrifugation of plasma before viral load analysis may eliminate the occurrence of this spurious low-level viraemia.

  9. Simple PCR assays improve the sensitivity of HIV-1 subtype B drug resistance testing and allow linking of resistance mutations.

    Directory of Open Access Journals (Sweden)

    Jeffrey A Johnson

    Full Text Available BACKGROUND: The success of antiretroviral therapy is known to be compromised by drug-resistant HIV-1 at frequencies detectable by conventional bulk sequencing. Currently, there is a need to assess the clinical consequences of low-frequency drug resistant variants occurring below the detection limit of conventional genotyping. Sensitive detection of drug-resistant subpopulations, however, requires simple and practical methods for routine testing. METHODOLOGY: We developed highly-sensitive and simple real-time PCR assays for nine key drug resistance mutations and show that these tests overcome substantial sequence heterogeneity in HIV-1 clinical specimens. We specifically used early wildtype virus samples from the pre-antiretroviral drug era to measure background reactivity and were able to define highly-specific screening cut-offs that are up to 67-fold more sensitive than conventional genotyping. We also demonstrate that sequencing the mutation-specific PCR products provided a direct and novel strategy to further detect and link associated resistance mutations, allowing easy identification of multi-drug-resistant variants. Resistance mutation associations revealed in mutation-specific amplicon sequences were verified by clonal sequencing. SIGNIFICANCE: Combined, sensitive real-time PCR testing and mutation-specific amplicon sequencing provides a powerful and simple approach that allows for improved detection and evaluation of HIV-1 drug resistance mutations.

  10. 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.

  11. DNA vaccines expressing soluble CD4-envelope proteins fused to C3d elicit cross-reactive neutralizing antibodies to HIV-1

    International Nuclear Information System (INIS)

    Bower, Joseph F.; Green, Thomas D.; Ross, Ted M.

    2004-01-01

    DNA vaccines expressing the envelope (Env) of the human immunodeficiency virus type 1 (HIV-1) have been relatively ineffective at generating high-titer, long-lasting, neutralizing antibodies in a variety of animal models. In this study, DNA vaccines were constructed to express a fusion protein of the soluble human CD4 (sCD4) and the gp120 subunit of the HIV-1 envelope. To enhance the immunogenicity of the expressed fusion protein, three copies of the murine C3d (mC3d 3 ) were added to the carboxyl terminus of the complex. Monoclonal antibodies that recognize CD4-induced epitopes on gp120 efficiently bound to sCD4-gp120 or sCD4-gp120-mC3d 3 . In addition, both sCD4-gp120 and sCD4-gp120-mC3d 3 bound to cells expressing appropriate coreceptors in the absence of cell surface hCD4. Mice (BALB/c) vaccinated with DNA vaccines expressing either gp120-mC3d 3 or sCD4-gp120-mC3d 3 elicited antibodies that neutralized homologous virus infection. However, the use of sCD4-gp120-mC3d 3 -DNA elicited the highest titers of neutralizing antibodies that persisted after depletion of anti-hCD4 antibodies. Interestingly, only mice vaccinated with DNA expressing sCD4-gp120-mC3d 3 had antibodies that elicited cross-protective neutralizing antibodies. The fusion of sCD4 to the HIV-1 envelope exposes neutralizing epitopes that elicit broad protective immunity when the fusion complex is coupled with the molecular adjuvant, C3d

  12. Lignosulfonic acid exhibits broadly anti-HIV-1 activity--potential as a microbicide candidate for the prevention of HIV-1 sexual transmission.

    Directory of Open Access Journals (Sweden)

    Min Qiu

    Full Text Available Some secondary metabolites from plants show to have potent inhibitory activities against microbial pathogens, such as human immunodeficiency virus (HIV, herpes simplex virus (HSV, Treponema pallidum, Neisseria gonorrhoeae, etc. Here we report that lignosulfonic acid (LSA, a polymeric lignin derivative, exhibits potent and broad activity against HIV-1 isolates of diverse subtypes including two North America strains and a number of Chinese clinical isolates values ranging from 21.4 to 633 nM. Distinct from other polyanions, LSA functions as an entry inhibitor with multiple targets on viral gp120 as well as on host receptor CD4 and co-receptors CCR5/CXCR4. LSA blocks viral entry as determined by time-of-drug addiction and cell-cell fusion assays. Moreover, LSA inhibits CD4-gp120 interaction by blocking the binding of antibodies specific for CD4-binding sites (CD4bs and for the V3 loop of gp120. Similarly, LSA interacts with CCR5 and CXCR4 via its inhibition of specific anti-CCR5 and anti-CXCR4 antibodies, respectively. Interestingly, the combination of LSA with AZT and Nevirapine exhibits synergism in viral inhibition. For the purpose of microbicide development, LSA displays low in vitro cytotoxicity to human genital tract epithelial cells, does not stimulate NF-κB activation and has no significant up-regulation of IL-1α/β and IL-8 as compared with N-9. Lastly, LSA shows no adverse effect on the epithelial integrity and the junctional protein expression. Taken together, our findings suggest that LSA can be a potential candidate for tropical microbicide.

  13. High-throughput SHAPE analysis reveals structures in HIV-1 genomic RNA strongly conserved across distinct biological states.

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    Kevin A Wilkinson

    2008-04-01

    Full Text Available Replication and pathogenesis of the human immunodeficiency virus (HIV is tightly linked to the structure of its RNA genome, but genome structure in infectious virions is poorly understood. We invent high-throughput SHAPE (selective 2'-hydroxyl acylation analyzed by primer extension technology, which uses many of the same tools as DNA sequencing, to quantify RNA backbone flexibility at single-nucleotide resolution and from which robust structural information can be immediately derived. We analyze the structure of HIV-1 genomic RNA in four biologically instructive states, including the authentic viral genome inside native particles. Remarkably, given the large number of plausible local structures, the first 10% of the HIV-1 genome exists in a single, predominant conformation in all four states. We also discover that noncoding regions functioning in a regulatory role have significantly lower (p-value < 0.0001 SHAPE reactivities, and hence more structure, than do viral coding regions that function as the template for protein synthesis. By directly monitoring protein binding inside virions, we identify the RNA recognition motif for the viral nucleocapsid protein. Seven structurally homologous binding sites occur in a well-defined domain in the genome, consistent with a role in directing specific packaging of genomic RNA into nascent virions. In addition, we identify two distinct motifs that are targets for the duplex destabilizing activity of this same protein. The nucleocapsid protein destabilizes local HIV-1 RNA structure in ways likely to facilitate initial movement both of the retroviral reverse transcriptase from its tRNA primer and of the ribosome in coding regions. Each of the three nucleocapsid interaction motifs falls in a specific genome domain, indicating that local protein interactions can be organized by the long-range architecture of an RNA. High-throughput SHAPE reveals a comprehensive view of HIV-1 RNA genome structure, and further

  14. CCL28 induces mucosal homing of HIV-1-specific IgA-secreting plasma cells in mice immunized with HIV-1 virus-like particles.

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    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.

  15. 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.

  16. 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

  17. Variations in the Biological Functions of HIV-1 Clade C Envelope in a SHIV-Infected Rhesus Macaque during Disease Progression.

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    For Yue Tso

    Full Text Available A better understanding of how the biological functions of the HIV-1 envelope (Env changes during disease progression may aid the design of an efficacious anti-HIV-1 vaccine. Although studies from patient had provided some insights on this issue, the differences in the study cohorts and methodology had make it difficult to reach a consensus of the variations in the HIV-1 Env functions during disease progression. To this end, an animal model that can be infected under controlled environment and reflect the disease course of HIV-1 infection in human will be beneficial. Such an animal model was previously demonstrated by the infection of macaque with SHIV, expressing HIV-1 clade C Env V1-V5 region. By using this model, we examined the changes in biological functions of Env in the infected animal over the entire disease course. Our data showed an increase in the neutralization resistance phenotype over time and coincided with the decrease in the net charges of the V1-V5 region. Infection of PBMC with provirus expressing various Env clones, isolated from the infected animal over time, showed a surprisingly better replicative fitness for viruses expressing the Env from early time point. Biotinylation and ELISA data also indicated a decrease of cell-surface-associated Env and virion-associated gp120 content with disease progression. This decrease did not affect the CD4-binding capability of Env, but were positively correlated with the decrease of Env fusion ability. Interestingly, some of these changes in biological functions reverted to the pre-AIDS level during advance AIDS. These data suggested a dynamic relationship between the Env V1-V5 region with the host immune pressure. The observed changes of biological functions in this setting might reflect and predict those occurring during natural disease progression in human.

  18. Synthesis of single- and double-chain fluorocarbon and hydrocarbon galactosyl amphiphiles and their anti-HIV-1 activity.

    Science.gov (United States)

    Faroux-Corlay, B; Clary, L; Gadras, C; Hammache, D; Greiner, J; Santaella, C; Aubertin, A M; Vierling, P; Fantini, J

    2000-07-24

    Galactosylceramide (GalCer) is an alternative receptor allowing HIV-1 entry into CD4(-)/GalCer(+) cells. This glycosphingolipid recognizes the V3 loop of HIV gp120, which plays a key role in the fusion of the HIV envelope and cellular membrane. To inhibit HIV uptake and infection, we designed and synthesized analogs of GalCer. These amphiphiles and bolaamphiphiles consist of single and double hydrocarbon and/or fluorocarbon chain beta-linked to galactose and galactosamine. They derive from serine (GalSer), cysteine (GalCys), and ethanolamine (GalAE). The anti-HIV activity and cytotoxicity of these galactolipids were evaluated in vitro on CEM-SS (a CD4(+) cell line), HT-29, a CD4(-) cell line expressing high levels of GalCer receptor, and/or HT29 genetically modified to express CD4. GalSer and GalAE derivatives, tested in aqueous medium or as part of liposome preparation, showed moderate anti-HIV-1 activities (IC50 in the 20-220 microM range), whereas none of the GalCys derivatives was found to be active. Moreover, only some of these anti-HIV active analogs inhibited the binding of [3H]suramin (a polysulfonyl compound which displays a high affinity for the V3 loop) to SPC3, a synthetic peptide which contains the conserved GPGRAF region of the V3 loop. Our results most likely indicate that the neutralization of the virion through masking of this conserved V3 loop region is not the only mechanism involved in the HIV-1 antiviral activity of our GalCer analogs.

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

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    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.

  20. 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.

  1. 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

  2. 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

  3. Chemokines and Chemokine Receptors in Susceptibility to HIV-1 Infection and Progression to AIDS

    Directory of Open Access Journals (Sweden)

    Animesh Chatterjee

    2012-01-01

    Full Text Available A multitude of host genetic factors plays a crucial role in susceptibility to HIV-1 infection and progression to AIDS, which is highly variable among individuals and populations. This review focuses on the chemokine-receptor and chemokine genes, which were extensively studied because of their role as HIV co-receptor or co-receptor competitor and influences the susceptibility to HIV-1 infection and progression to AIDS in HIV-1 infected individuals.

  4. 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

  5. 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

  6. Schistosomiasis and HIV-1 infection in rural Zimbabwe: effect of treatment of schistosomiasis on CD4 cell count and plasma HIV-1 RNA load

    DEFF Research Database (Denmark)

    Kallestrup, Per; Zinyama, Rutendo; Gomo, Exnevia

    2005-01-01

    To determine whether treatment of schistosomiasis has an effect on the course of human immunodeficiency virus type 1 (HIV-1) infection, individuals with schistosomiasis and with or without HIV-1 infection were randomized to receive praziquantel treatment at inclusion or after a delay of 3 months......; 287 participants were included in the study, and 227 (79%) were followed up. Among the 130 participants who were coinfected, those who received early treatment (n=64) had a significantly lower increase in plasma HIV-1 RNA load than did those who received delayed treatment (n=66) (P...

  7. Inhibition of HIV-1 by a natural compound

    CSIR Research Space (South Africa)

    Van den Berg, N

    2011-06-01

    Full Text Available cells. ?CSIR for funding. REFERENCES ACKNOWLEDGEMENTS FUTURE WORK The BP36 compound will be screened against more HIV-1 subtype C molecular clones to determine its efficacy. An intensive programme is currently underway to develop suitable... for HIV specificity ? 100 >100 0.5476 HXB2 B Male to Male France 0.1198 0.0551 0.4738 CAP45 C Female sex worker SA 0.3527 0.2773 0.1735 ZM53 C Female to Male Zambia 0.8461 0.1517 0.2512 ZM109 C Male to Female Zambia 0.2957 0.0100 0.0110 ZM135 C...

  8. Molecular and biological diversity of HIV-1 in Brazil

    Directory of Open Access Journals (Sweden)

    José Carlos Couto-Fernandez

    1992-06-01

    Full Text Available To determine the genomic polymorphism and biological properties present in HIV-1 Brazilian isolates, were analyzed five viral isolates obtained from patients residing in Rio de Janeiro (P1 and P5, São Paulo (P3 and Bahia (P2 and P4 states. For each viral isolate in vitro characteristics such as replication rate, syncytium-inducing capacity and cell death were observed in lymphoblastoid (H9, CEM and peripheral blood mononuclear cells as well as monocytoid (U937 cells. In addition, the evaluation of the restriction fragment lenght polymorphism of these isolates was also performed using a panel of endonucleases such as Hind III, Bgl II, Sac I, Pst I, Kpn I and Eco RI. One of the isolates (P1, showed the highest phenotypic and genotypic divergence, when compared to others. The results found suggest a HIV heterogeneity in Brazil similar to that already described in other regions of the world.

  9. NMR structure of the HIV-1 reverse transcriptase thumb subdomain

    Energy Technology Data Exchange (ETDEWEB)

    Sharaf, Naima G. [University of Pittsburgh, School of Medicine, Department of Structural Biology and Pittsburgh Center for HIV Protein Interactions (United States); Brereton, Andrew E. [Oregon State University, Department of Biochemistry and Biophysics, 2011 Ag & Life Sciences Bldg (United States); Byeon, In-Ja L. [University of Pittsburgh, School of Medicine, Department of Structural Biology and Pittsburgh Center for HIV Protein Interactions (United States); Andrew Karplus, P. [Oregon State University, Department of Biochemistry and Biophysics, 2011 Ag & Life Sciences Bldg (United States); Gronenborn, Angela M., E-mail: amg100@pitt.edu [University of Pittsburgh, School of Medicine, Department of Structural Biology and Pittsburgh Center for HIV Protein Interactions (United States)

    2016-12-15

    The solution NMR structure of the isolated thumb subdomain of HIV-1 reverse transcriptase (RT) has been determined. A detailed comparison of the current structure with dozens of the highest resolution crystal structures of this domain in the context of the full-length enzyme reveals that the overall structures are very similar, with only two regions exhibiting local conformational differences. The C-terminal capping pattern of the αH helix is subtly different, and the loop connecting the αI and αJ helices in the p51 chain of the full-length p51/p66 heterodimeric RT differs from our NMR structure due to unique packing interactions in mature RT. Overall, our data show that the thumb subdomain folds independently and essentially the same in isolation as in its natural structural context.

  10. HIV-1 CRF_BC recombinants infection in China: molecular epidemic and characterizations.

    Science.gov (United States)

    Ouyang, Yabo; Shao, Yiming; Ma, Liying

    2012-03-01

    CRF_BC recombinant strains were first identified in China and are one of the most prevalent and characteristically unique HIV-1 subtypes across China. Here we aim to review the published data about HIV-1 CRF_BC recombinant strains epidemic in China and to characterize the genetics, biology and drug resistance of this virus. This study may help to better understand the current situation of HIV-1 CRF_BC prevalence and facilitate the development of vaccines and more efficient anti-HIV-1 regimens in China.

  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. Illness during Pregnancy and Bacterial Vaginosis are Associated with In Utero HIV-1 Transmission

    Science.gov (United States)

    Farquhar, Carey; Mbori-Ngacha, Dorothy; Overbaugh, Julie; Wamalwa, Dalton; Harris, Jennifer; Bosire, Rose; John-Stewart, Grace

    2009-01-01

    HIV-1 transmission in utero accounts for 20–30% of vertical transmission events in breastfeeding populations. In a prospective study of 463 HIV-1-infected mothers and infants, illness during pregnancy was associated with 2.6-fold increased risk of in utero HIV-1 transmission (95% CI 1.2, 5.8) and bacterial vaginosis with a 3-fold increase (95% CI 1.0–7.0) after adjusting for maternal HIV-1 viral load. Interventions targeting these novel risk factors could lead to more effective prevention of transmission during pregnancy. PMID:19952542

  13. 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.

  14. Proteomics in the investigation of HIV-1 interactions with host proteins.

    Science.gov (United States)

    Li, Ming

    2015-02-01

    Productive HIV-1 infection depends on host machinery, including a broad array of cellular proteins. Proteomics has played a significant role in the discovery of HIV-1 host proteins. In this review, after a brief survey of the HIV-1 host proteins that were discovered by proteomic analyses, I focus on analyzing the interactions between the virion and host proteins, as well as the technologies and strategies used in those proteomic studies. With the help of proteomics, the identification and characterization of HIV-1 host proteins can be translated into novel antiretroviral therapeutics. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  15. Stochastic modeling for dynamics of HIV-1 infection using cellular automata: A review.

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    Precharattana, Monamorn

    2016-02-01

    Recently, the description of immune response by discrete models has emerged to play an important role to study the problems in the area of human immunodeficiency virus type 1 (HIV-1) infection, leading to AIDS. As infection of target immune cells by HIV-1 mainly takes place in the lymphoid tissue, cellular automata (CA) models thus represent a significant step in understanding when the infected population is dispersed. Motivated by these, the studies of the dynamics of HIV-1 infection using CA in memory have been presented to recognize how CA have been developed for HIV-1 dynamics, which issues have been studied already and which issues still are objectives in future studies.

  16. Dynamics of HIV-1 RNA Near the Plasma Membrane during Virus Assembly.

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    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

  17. Analysis of the initiating events in HIV-1 particle assembly and genome packaging.

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    Sebla B Kutluay

    2010-11-01

    Full Text Available HIV-1 Gag drives a number of events during the genesis of virions and is the only viral protein required for the assembly of virus-like particles in vitro and in cells. Although a reasonable understanding of the processes that accompany the later stages of HIV-1 assembly has accrued, events that occur at the initiation of assembly are less well defined. In this regard, important uncertainties include where in the cell Gag first multimerizes and interacts with the viral RNA, and whether Gag-RNA interaction requires or induces Gag multimerization in a living cell. To address these questions, we developed assays in which protein crosslinking and RNA/protein co-immunoprecipitation were coupled with membrane flotation analyses in transfected or infected cells. We found that interaction between Gag and viral RNA occurred in the cytoplasm and was independent of the ability of Gag to localize to the plasma membrane. However, Gag:RNA binding was stabilized by the C-terminal domain (CTD of capsid (CA, which participates in Gag-Gag interactions. We also found that Gag was present as monomers and low-order multimers (e.g. dimers but did not form higher-order multimers in the cytoplasm. Rather, high-order multimers formed only at the plasma membrane and required the presence of a membrane-binding signal, but not a Gag domain (the CA-CTD that is essential for complete particle assembly. Finally, sequential RNA-immunoprecipitation assays indicated that at least a fraction of Gag molecules can form multimers on viral genomes in the cytoplasm. Taken together, our results suggest that HIV-1 particle assembly is initiated by the interaction between Gag and viral RNA in the cytoplasm and that this initial Gag-RNA encounter involves Gag monomers or low order multimers. These interactions per se do not induce or require high-order Gag multimerization in the cytoplasm. Instead, membrane interactions are necessary for higher order Gag multimerization and subsequent

  18. Improved therapy-success prediction with GSS estimated from clinical HIV-1 sequences.

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    Pironti, Alejandro; Pfeifer, Nico; Kaiser, Rolf; Walter, Hauke; Lengauer, Thomas

    2014-01-01

    Rules-based HIV-1 drug-resistance interpretation (DRI) systems disregard many amino-acid positions of the drug's target protein. The aims of this study are (1) the development of a drug-resistance interpretation system that is based on HIV-1 sequences from clinical practice rather than hard-to-get phenotypes, and (2) the assessment of the benefit of taking all available amino-acid positions into account for DRI. A dataset containing 34,934 therapy-naïve and 30,520 drug-exposed HIV-1 pol sequences with treatment history was extracted from the EuResist database and the Los Alamos National Laboratory database. 2,550 therapy-change-episode baseline sequences (TCEB) were assigned to test set A. Test set B contains 1,084 TCEB from the HIVdb TCE repository. Sequences from patients absent in the test sets were used to train three linear support vector machines to produce scores that predict drug exposure pertaining to each of 20 antiretrovirals: the first one uses the full amino-acid sequences (DEfull), the second one only considers IAS drug-resistance positions (DEonlyIAS), and the third one disregards IAS drug-resistance positions (DEnoIAS). For performance comparison, test sets A and B were evaluated with DEfull, DEnoIAS, DEonlyIAS, geno2pheno[resistance], HIVdb, ANRS, HIV-GRADE, and REGA. Clinically-validated cut-offs were used to convert the continuous output of the first four methods into susceptible-intermediate-resistant (SIR) predictions. With each method, a genetic susceptibility score (GSS) was calculated for each therapy episode in each test set by converting the SIR prediction for its compounds to integer: S=2, I=1, and R=0. The GSS were used to predict therapy success as defined by the EuResist standard datum definition. Statistical significance was assessed using a Wilcoxon signed-rank test. A comparison of the therapy-success prediction performances among the different interpretation systems for test set A can be found in Table 1, while those for test set

  19. The RNA binding protein HuR does not interact directly with HIV-1 reverse transcriptase and does not affect reverse transcription in vitro

    Directory of Open Access Journals (Sweden)

    Gronenborn Angela M

    2010-05-01

    Full Text Available Abstract Background Lemay et al recently reported that the RNA binding protein HuR directly interacts with the ribonuclease H (RNase H domain of HIV-1 reverse transcriptase (RT and influences the efficiency of viral reverse transcription (Lemay et al., 2008, Retrovirology 5:47. HuR is a member of the embryonic lethal abnormal vision protein family and contains 3 RNA recognition motifs (RRMs that bind AU-rich elements (AREs. To define the structural determinants of the HuR-RT interaction and to elucidate the mechanism(s by which HuR influences HIV-1 reverse transcription activity in vitro, we cloned and purified full-length HuR as well as three additional protein constructs that contained the N-terminal and internal RRMs, the internal and C-terminal RRMs, or the C-terminal RRM only. Results All four HuR proteins were purified and characterized by biophysical methods. They are well structured and exist as monomers in solution. No direct protein-protein interaction between HuR and HIV-1 RT was detected using NMR titrations with 15N labeled HuR variants or the 15N labeled RNase H domain of HIV-1 RT. Furthermore, HuR did not significantly affect the kinetics of HIV-1 reverse transcription in vitro, even on RNA templates that contain AREs. Conclusions Our results suggest that HuR does not impact HIV-1 replication through a direct protein-protein interaction with the viral RT.

  20. Haplotypes in CCR5-CCR2, CCL3 and CCL5 are associated with natural resistance to HIV-1 infection in a Colombian cohort.

    Science.gov (United States)

    Vega, Jorge A; Villegas-Ospina, Simón; Aguilar-Jiménez, Wbeimar; Rugeles, María T; Bedoya, Gabriel; Zapata, Wildeman

    2017-06-01

    Variants in genes encoding for HIV-1 co-receptors and their natural ligands have been individually associated to natural resistance to HIV-1 infection. However, the simultaneous presence of these variants has been poorly studied. To evaluate the association of single and multilocus haplotypes in genes coding for the viral co-receptors CCR5 and CCR2, and their ligands CCL3 and CCL5, with resistance or susceptibility to HIV-1 infection. Nine variants in CCR5-CCR2, two SNPs in CCL3 and two in CCL5 were genotyped by PCR-RFLP in 35 seropositive (cases) and 49 HIV-1-exposed seronegative Colombian individuals (controls). Haplotypes were inferred using the Arlequin software, and their frequency in individual or combined loci was compared between cases and controls by the chi-square test. A p' value ;0.05 after Bonferroni correction was considered significant. Homozygosis of the human haplogroup (HH) E was absent in controls and frequent in cases, showing a tendency to susceptibility. The haplotypes C-C and T-T in CCL3 were associated with susceptibility (p'=0.016) and resistance (p';0.0001) to HIV-1 infection, respectively. Finally, in multilocus analysis, the haplotype combinations formed by HHC in CCR5-CCR2, T-T in CCL3 and G-C in CCL5 were associated with resistance (p'=0.006). Our results suggest that specific combinations of variants in genes from the same signaling pathway can define an HIV-1 resistant phenotype. Despite our small sample size, our statistically significant associations suggest strong effects; however, these results should be further validated in larger cohorts.

  1. Frequent Cross-Resistance to Dapivirine in HIV-1 Subtype C-Infected Individuals after First-Line Antiretroviral Therapy Failure in South Africa.

    Science.gov (United States)

    Penrose, Kerri J; Wallis, Carole L; Brumme, Chanson J; Hamanishi, Kristen A; Gordon, Kelley C; Viana, Raquel V; Harrigan, P Richard; Mellors, John W; Parikh, Urvi M

    2017-02-01

    A vaginal ring containing dapivirine (DPV) has shown moderate protective efficacy against HIV-1 acquisition, but the activity of DPV against efavirenz (EFV)- and nevirapine (NVP)-resistant viruses that could be transmitted is not well defined. We investigated DPV cross-resistance of subtype C HIV-1 from individuals on failing NVP- or EFV-containing antiretroviral therapy (ART) in South Africa. Plasma samples were obtained from individuals with >10,000 copies of HIV RNA/ml and with HIV-1 containing at least one non-nucleoside reverse transcriptase (NNRTI) mutation. Susceptibility to NVP, EFV, and DPV in TZM-bl cells was determined for recombinant HIV-1 LAI containing bulk-amplified, plasma-derived, full-length reverse transcriptase sequences. Fold change (FC) values were calculated compared with a composite 50% inhibitory concentration (IC 50 ) from 12 recombinant subtype C HIV-1 LAI plasma-derived viruses from treatment-naive individuals in South Africa. A total of 25/100 (25%) samples showed >500-FCs to DPV compared to treatment-naive samples with IC 50 s exceeding the maximum DPV concentration tested (132 ng/ml). A total of 66/100 (66%) samples displayed 3- to 306-FCs, with a median IC 50 of 17.6 ng/ml. Only 9/100 (9%) samples were susceptible to DPV (FC 500-fold resistance to DPV compared to samples with a ≤500-fold resistance. A total of 91% of samples with NNRTI-resistant HIV-1 from individuals on failing first-line ART in South Africa exhibited ≥3-fold cross-resistance to DPV. This level of resistance exceeds expected plasma concentrations, but very high genital tract DPV concentrations from DPV ring use could block viral replication. It is critically important to assess the frequency of transmitted and selected DPV resistance in individuals using the DPV ring. Copyright © 2017 American Society for Microbiology.

  2. An assay to monitor HIV-1 protease activity for the identification of novel inhibitors in T-cells.

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    Brett J Hilton

    Full Text Available The emergence of resistant HIV strains, together with the severe side-effects of existing drugs and lack of development of effective anti-HIV vaccines highlight the need for novel antivirals, as well as innovative methods to facilitate their discovery. Here, we have developed an assay in T-cells to monitor the proteolytic activity of the HIV-1 protease (PR. The assay is based on the inducible expression of HIV-1 PR fused within the Gal4 DNA-binding and transactivation domains. The fusion protein binds to the Gal4 responsive element and activates the downstream reporter, enhanced green fluorescent protei