WorldWideScience

Sample records for hiv specific cellular

  1. HIV-specific humoral and cellular immunity in rabbits vaccinated with recombinant human immunodeficiency virus-like gag-env particles

    Energy Technology Data Exchange (ETDEWEB)

    Haffar, O.K.; Smithgall, M.D.; Moran, P.A.; Travis, B.M.; Zarling, J.M.; Hu, S.L. (Department of Virology, Bristol-Myers Squibb Pharmaceutical Research Institute-Seattle, WA (USA))

    1991-08-01

    Recombinant human immunodeficiency virus type-1 (HIV-1)-like gag-env particles produced in mammalian cells were inoculated into two New Zealand white rabbits. In parallel, two control rabbits were inoculated with the homologous HIV-1 virions inactivated by ultraviolet light (uv) and psoralen treatments. The humoral and cellular immune responses to HIV-1 were evaluated for both groups of animals. Recombinant particles elicited humoral immunity that was specific for all the viral structural proteins. The antibodies recognized both denatured and nondenatured proteins. Moreover, the sera neutralized the in vitro infectivity of the homologous virus in CEM cells. Importantly, the recombinant particles also generated a T helper response by priming with the HIV proteins. Similar results were observed with inactivated virus immunization. Therefore, the authors results suggest that the recombinant HIV-like particles elicit functional humoral immunity as well as cellular immunity and represent a novel vaccine candidate for AIDS.

  2. HIV-specific CD4-induced Antibodies Mediate Broad and Potent Antibody-dependent Cellular Cytotoxicity Activity and are Commonly Detected in Plasma from HIV-infected Humans

    Directory of Open Access Journals (Sweden)

    Katherine L. Williams

    2015-10-01

    Full Text Available HIV-specific antibodies (Abs can reduce viral burden by blocking new rounds of infection or by destroying infected cells via activation of effector cells through Fc–FcR interaction. This latter process, referred to as antibody-dependent cellular cytotoxicity (ADCC, has been associated with viral control and improved clinical outcome following both HIV and SIV infections. Here we describe an HIV viral-like particle (VLP-based sorting strategy that led to identification of HIV-specific memory B cells encoding Abs that mediate ADCC from a subtype A-infected Kenyan woman at 914 days post-infection. Using this strategy, 12 HIV-envelope-specific monoclonal antibodies (mAbs were isolated and three mediated potent ADCC activity when compared to well-characterized ADCC mAbs. The ADCC-mediating Abs also mediated antibody-dependent cell-mediated virus inhibition (ADCVI, which provides a net measure of Fc receptor-triggered effects against replicating virus. Two of the three ADCC-mediating Abs targeted a CD4-induced (CD4i epitope also bound by the mAb C11; the third antibody targeted the N-terminus of V3. Both CD4i Abs identified here demonstrated strong cross-clade breadth with activity against 10 of 11 envelopes tested, including those from clades A, B, C, A/D and C/D, whereas the V3-specific antibody showed more limited breadth. Variants of these CD4i, C11-like mAbs engineered to interrupt binding to FcγRs inhibited a measurable percentage of the donor's ADCC activity starting as early as 189 days post-infection. C11-like antibodies also accounted for between 18–78% of ADCC activity in 9 chronically infected individuals from the same cohort study. Further, the two CD4i Abs originated from unique B cells, suggesting that antibodies targeting this epitope can be commonly produced. Taken together, these data provide strong evidence that CD4i, C11-like antibodies develop within the first 6 months of infection and they can arise from unique B

  3. Cyclophilin A as a potential genetic adjuvant to improve HIV-1 Gag DNA vaccine immunogenicity by eliciting broad and long-term Gag-specific cellular immunity in mice

    Science.gov (United States)

    Hou, Jue; Zhang, Qicheng; Liu, Zheng; Wang, Shuhui; Li, Dan; Liu, Chang; Liu, Ying; Shao, Yiming

    2016-01-01

    Previous research has shown that host Cyclophilin A (CyPA) can promote dendritic cell maturation and the subsequent innate immune response when incorporated into an HIV-1 Gag protein to circumvent the resistance of dendritic cells to HIV-1 infection. This led us to hypothesize that CyPA may improve HIV-1 Gag-specific vaccine immunogenicity via binding with Gag antigen. The adjuvant effect of CyPA was evaluated using a DNA vaccine with single or dual expression cassettes. Mouse studies indicated that CyPA specifically and markedly promoted HIV-1 Gag-specific cellular immunity but not an HIV-1 Env-specific cellular response. The Gag/CyPA dual expression cassettes stimulated a greater Gag-specific cellular immune response, than Gag immunization alone. Furthermore, CyPA induced a broad Gag-specific T cell response and strong cellular immunity that lasted up to 5 months. In addition, CyPA skewed to cellular rather than humoral immunity. To investigate the mechanisms of the adjuvant effect, site-directed mutagenesis in CyPA, including active site residues H54Q and F60A resulted in mutants that were co-expressed with Gag in dual cassettes. The immune response to this vaccine was analyzed in vivo. Interestingly, the wild type CyPA markedly increased Gag cellular immunity, but the H54Q and F60A mutants drastically reduced CyPA adjuvant activation. Therefore, we suggest that the adjuvant effect of CyPA was based on Gag-CyPA-specific interactions. Herein, we report that Cyclophilin A can augment HIV-1 Gag-specific cellular immunity as a genetic adjuvant in multiplex DNA immunization strategies, and that activity of this adjuvant is specific, broad, long-term, and based on Gag-CyPA interaction. PMID:26305669

  4. HIV-Specific Antibody-Dependent Cellular Cytotoxicity (ADCC) -Mediating Antibodies Decline while NK Cell Function Increases during Antiretroviral Therapy (ART).

    Science.gov (United States)

    Jensen, Sanne Skov; Fomsgaard, Anders; Borggren, Marie; Tingstedt, Jeanette Linnea; Gerstoft, Jan; Kronborg, Gitte; Rasmussen, Line Dahlerup; Pedersen, Court; Karlsson, Ingrid

    2015-01-01

    Understanding alterations in HIV-specific immune responses during antiretroviral therapy (ART), such as antibody-dependent cellular cytotoxicity (ADCC), is important in the development of novel strategies to control HIV-1 infection. This study included 53 HIV-1 positive individuals. We evaluated the ability of effector cells and antibodies to mediate ADCC separately and in combination using the ADCC-PanToxiLux assay. The ability of the peripheral blood mononuclear cells (PBMCs) to mediate ADCC was significantly higher in individuals who had been treated with ART before seroconversion, compared to the individuals initiating ART at a low CD4+ T cell count (ART-naïve individuals. The frequency of CD16 expressing natural killer (NK) cells correlated with both the duration of ART and Granzyme B (GzB) activity. In contrast, the plasma titer of antibodies mediating ADCC declined during ART. These findings suggest improved cytotoxic function of the NK cells if initiating ART early during infection, while the levels of ADCC mediating antibodies declined during ART.

  5. Cellular immune responses to HIV

    Science.gov (United States)

    McMichael, Andrew J.; Rowland-Jones, Sarah L.

    2001-04-01

    The cellular immune response to the human immunodeficiency virus, mediated by T lymphocytes, seems strong but fails to control the infection completely. In most virus infections, T cells either eliminate the virus or suppress it indefinitely as a harmless, persisting infection. But the human immunodeficiency virus undermines this control by infecting key immune cells, thereby impairing the response of both the infected CD4+ T cells and the uninfected CD8+ T cells. The failure of the latter to function efficiently facilitates the escape of virus from immune control and the collapse of the whole immune system.

  6. Modeling dynamics of HIV infected cells using stochastic cellular automaton

    Science.gov (United States)

    Precharattana, Monamorn; Triampo, Wannapong

    2014-08-01

    Ever since HIV was first diagnosed in human, a great number of scientific works have been undertaken to explore the biological mechanisms involved in the infection and progression of the disease. Several cellular automata (CA) models have been introduced to gain insights into the dynamics of the disease progression but none of them has taken into account effects of certain immune cells such as the dendritic cells (DCs) and the CD8+ T lymphocytes (CD8+ T cells). In this work, we present a CA model, which incorporates effects of the HIV specific immune response focusing on the cell-mediated immunities, and investigate the interaction between the host immune response and the HIV infected cells in the lymph nodes. The aim of our work is to propose a model more realistic than the one in Precharattana et al. (2010) [10], by incorporating roles of the DCs, the CD4+ T cells, and the CD8+ T cells into the model so that it would reproduce the HIV infection dynamics during the primary phase of HIV infection.

  7. 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.

  8. Modulation of innate and adaptive cellular immunity relevant to HIV-1 vaccine design by seminal plasma.

    Science.gov (United States)

    Selva, Kevin J; Kent, Stephen J; Parsons, Matthew S

    2017-01-28

    Mucosal exposure to HIV-1 infection generally occurs in the presence of semen. Immunomodulation by seminal plasma is well described in the reproductive biology literature. Little is known, however, about the impact of seminal plasma on innate and adaptive anti-HIV-1 cellular immunity. The study investigated the effects of seminal plasma on immune responses considered important for prophylactic HIV-1 vaccine development, namely innate and adaptive cellular immunity mediated by natural killer (NK) cells and T cells, respectively. The ability of seminal plasma to modulate direct, antibody-dependent and cytokine-stimulated NK cell activation was assessed utilizing intracellular cytokine staining. Direct and antibody-dependent cellular cytotoxicity was assessed using lactate dehydrogenase release assays. The effects of seminal plasma on T-cell activation upon stimulation with staphylococcus enterotoxin B or HIV-1 Gag peptides were assessed by intracellular cytokine staining. The impact of seminal plasma on redirected cytolysis mediated by T cells was measured using lactate dehydrogenase release assays. Both direct and antibody-dependent NK cell activation were dramatically impaired by the presence of either HIV-1-uninfected or HIV-1-infected seminal plasma in a dose-dependent manner. Additionally, seminal plasma suppressed both direct and antibody-dependent NK cell-mediated cytolysis, including anti-HIV-1 antibody-dependent cytolysis of gp120-pulsed CEM.NKr-CCR5 cells. Finally, seminal plasma attenuated both HIV-1 Gag-specific and staphylococcus enterotoxin B-induced CTL activation. Semen contains potent immunosuppressors of both NK cell and CD8 T-cell-mediated anti-HIV-1 immune responses. This could impede attempts to provide vaccine-induced immunity to HIV-1.

  9. HIV migration between blood plasma and cellular subsets before and after HIV therapy.

    Science.gov (United States)

    Choi, Jun Yong; Chaillon, Antoine; Oh, Jin Ok; Ahn, Jin Young; Ann, Hae Won; Jung, In Young; Ahn, Mi-Young; Jeon, Yong Duk; Ku, Nam Su; Smith, Davey M; Kim, June Myung

    2016-04-01

    The cellular source of HIV RNA circulating in blood plasma remains unclear. Here, we investigated whether sequence analysis of HIV RNA populations circulating before combination antiretroviral therapy (cART) and HIV DNA populations in cellular subsets (CS) after cART could identify the cellular sources of circulating HIV RNA. Blood was collected from five subjects at cART initiation and again 6 months later. Naïve CD4+ T cells, resting central memory and effector memory CD4+ T cells, activated CD4+ T cells, monocytes, and natural killer cells were sorted using a fluorescence-activated cell sorter. HIV-1 env C2V3 sequences from HIV RNA in blood plasma and HIV DNA in CSs were generated using single genome sequencing. Sequences were evaluated for viral compartmentalization (Fst test) and migration events (MEs; Slatkin Maddison and cladistic measures) between blood plasma and each CS. Viral compartmentalization was observed in 88% of all cellular subset comparisons (range: 77-100% for each subject). Most observed MEs were directed from blood plasma to CSs (52 MEs, 85.2%). In particular, there was only viral movement from plasma to NK cells (15 MEs), monocytes (seven MEs), and naïve cells (five ME). We observed a total of nine MEs from activated CD4 cells (2/9 MEs), central memory T cells (3/9 MEs), and effector memory T cells (4/9 MEs) to blood plasma. Our results revealed that the HIV RNA population in blood plasma plays an important role in seeding various cellular reservoirs and that the cellular source of the HIV RNA population is activated central memory and effector memory T cells.

  10. The HIV-Specific Advance Directive

    Science.gov (United States)

    Singer, Peter A; Thiel, Elaine C; Salit, Irving; Flanagan, William; Naylor, C. David

    1997-01-01

    OBJECTIVE To determine whether persons living with HIV find a disease-specific advance directive more acceptable than a generic directive. DESIGN Randomized clinical trial. SETTING HIV consumer organization and hospital-based HIV clinic. PARTICIPANTS Volunteer sample of persons with HIV. INTERVENTIONS The disease-specific HIV Living Will, the generic Centre for Bioethics Living Will, or both. MEASUREMENTS AND MAIN RESULTS Of 101 participants who received both advance directives, 78 (77.2%) preferred the disease-specific HIV Living Will and 23 (22.8%) preferred the generic Centre for Bioethics Living Will (p < .001). Most participants who preferred the HIV Living Will did so because it was more specific or relevant to their situation. CONCLUSIONS Persons living with HIV prefer a disease-specific to a generic advance directive. They should be offered a disease-specific advance directive. Our findings should also encourage investigators to develop and evaluate disease-specific advance directives in other clinical settings. PMID:9436891

  11. Specific Elimination of Latently HIV-1 Infected Cells Using HIV-1 Protease-Sensitive Toxin Nanocapsules.

    Science.gov (United States)

    Wen, Jing; Yan, Ming; Liu, Yang; Li, Jie; Xie, Yiming; Lu, Yunfeng; Kamata, Masakazu; Chen, Irvin S Y

    2016-01-01

    Anti-retroviral drugs suppress HIV-1 plasma viremia to undetectable levels; however, latent HIV-1 persists in reservoirs within HIV-1-infected patients. The silent provirus can be activated through the use of drugs, including protein kinase C activators and histone deacetylase inhibitors. This "shock" approach is then followed by "kill" of the producing cells either through direct HIV-1-induced cell death or natural immune mechanisms. However, these mechanisms are relatively slow and effectiveness is unclear. Here, we develop an approach to specifically target and kill cells that are activated early in the process of virus production. We utilize a novel nanocapsule technology whereby the ricin A chain is encapsulated in an inactive form within a polymer shell. Specificity for release of the ricin A toxin is conferred by peptide crosslinkers that are sensitive to cleavage by HIV-1 protease. By using well-established latent infection models, J-Lat and U1 cells, we demonstrate that only within an HIV-1-producing cell expressing functional HIV-1 protease will the nanocapsule release its ricin A cargo, shutting down viral and cellular protein synthesis, and ultimately leading to rapid death of the producer cell. Thus, we provide proof of principle for a novel technology to kill HIV-1-producing cells without effects on non-target cells.

  12. Cellular restriction factors affecting the early stages of HIV replication.

    Science.gov (United States)

    Perez, Omar; Hope, Thomas J

    2006-02-01

    Several innate immune mechanisms exist in mammalian cells that prevent the replication of viruses. These cellular factors influence the tropism of retroviruses in mammalian cells by inducing a dominant restriction that acts after viral entry but before integration into the host genome. The identification of several cellular factors involved with the post entry block of HIV has recently been revealed. These recent advances identified the tripartite motif protein 5alpha (Trim5alpha) and the apolipoprotein B mRNA editing enzyme catalytic polypeptide-like 3G (APOBEC3G), which work to inactivate several retroviruses including HIV-1. The mechanism of restriction by these cellular proteins is unknown. Therefore, this review highlights recent advances in understanding the function of Trim5alpha and APOBEC3G.

  13. Polyfunctional HIV-Specific Antibody Responses Are Associated with Spontaneous HIV Control.

    Directory of Open Access Journals (Sweden)

    Margaret E Ackerman

    2016-01-01

    Full Text Available Elite controllers (ECs represent a unique model of a functional cure for HIV-1 infection as these individuals develop HIV-specific immunity able to persistently suppress viremia. Because accumulating evidence suggests that HIV controllers generate antibodies with enhanced capacity to drive antibody-dependent cellular cytotoxicity (ADCC that may contribute to viral containment, we profiled an array of extra-neutralizing antibody effector functions across HIV-infected populations with varying degrees of viral control to define the characteristics of antibodies associated with spontaneous control. While neither the overall magnitude of antibody titer nor individual effector functions were increased in ECs, a more functionally coordinated innate immune-recruiting response was observed. Specifically, ECs demonstrated polyfunctional humoral immune responses able to coordinately recruit ADCC, other NK functions, monocyte and neutrophil phagocytosis, and complement. This functionally coordinated response was associated with qualitatively superior IgG3/IgG1 responses, whereas HIV-specific IgG2/IgG4 responses, prevalent among viremic subjects, were associated with poorer overall antibody activity. Rather than linking viral control to any single activity, this study highlights the critical nature of functionally coordinated antibodies in HIV control and associates this polyfunctionality with preferential induction of potent antibody subclasses, supporting coordinated antibody activity as a goal in strategies directed at an HIV-1 functional cure.

  14. Molecular and cellular limits to somatosensory specificity

    Directory of Open Access Journals (Sweden)

    Viana Félix

    2008-04-01

    involved primarily in nerve impulse generation can also influence the gating of transducing channels, dramatically modifying their activation profile. Thus, we propose that the capacity exhibited by the different functional types of somatosensory receptor neurons to preferentially detect and encode specific stimuli into a discharge of nerve impulses, appears to result of a characteristic combinatorial expression of different ion channels in each neuronal type that finally determines their transduction and impulse firing properties. Transduction channels don't operate in isolation and their cellular context should also be taken into consideration to fully understand their function. Moreover, the inhomogeneous distribution of transduction and voltage-gated channels at soma, axonal branches and peripheral endings of primary sensory neurons influences the characteristics of the propagated impulse discharge that encodes the properties of the stimulus. Alteration of this concerted operation of ion channels in pathological conditions may underlie the changes in excitability accompanying peripheral sensory neuron injuries.

  15. HIV-specific T cell immunity across the entire HIV genome in Chinese men who have sex with men

    Institute of Scientific and Technical Information of China (English)

    ZHANG Xiao-yan; SHAO Yi-ming; HUANG Xiang-gang; XU Jian-qing; LI Shen-wei; JIANG Shu-lin; ZHANG Xiao-xi; LI Dong-liang; RUAN Yu-hua; XING Hui

    2006-01-01

    Background Man who has sex with man (MSM) is one of the high risk groups for spreading HIV/AIDS. It was reported that the most prevalent human immunodeficiency virus type 1 (HIV-1) strain among MSM is subtype B; however, T cell immunity remains unknown across the HIV-1 B genome in this population.Methods Using Elispot assay with synthetic peptides spanning the sequence of HIV-1 consensus B,HIV-1-specific cytotoxic T-cell lymphocyte responses were quantified among 3 treated and 19 untreated HIV-1 infected MSM from Beijing, China. Cross-sectional association between viral loads and cellular immune responses were analyzed.Results Peptide pools corresponding to each HIV-1 protein were used for Env, Gag, Pol, Nef, Tat/Rev, Vpr/Vpu and Vif. The results showed that the magnitude of T cell responses in the 3 treated HIV+ MSM group [median,770 spot forming cells (SFCs) per 106 peripheral blood mononuclear cells (PBMCs)] might be significantly lower than that in the 19 untreated HIV+ MSM group (median, 6175 SFCs per 106 PBMCs). Nef, Gag and Pol are the most frequently targeted HIV-1 antigens; and 16 subjects (73%) were identified with vigorous T cell immunity against each of these three proteins. The overall magnitude of T cell immunity closely related to its breadth (r=-0.72, P<0.05) and was inversely but weakly associated with viral loads (r=-0.15). Further analysis showed that both Gag (r=-0.24) and Pol specific T cells (r=-0.12) contributed to this inverse association whereas Nef specific T cells showed no association with viral loads.Conclusions The magnitude of HIV-1 specific T cells is inversely but weakly associated with viral loads among MSM; HIV-specific T cell responses against conservative sequences (Gag and Poi) are the main contributors to this association among Chinese HIV+ MSM. These findings have important implications for vaccine design.

  16. A novel HIV vaccine adjuvanted by IC31 induces robust and persistent humoral and cellular immunity.

    Directory of Open Access Journals (Sweden)

    Laura Pattacini

    Full Text Available The HIV vaccine strategy that, to date, generated immune protection consisted of a prime-boost regimen using a canarypox vector and an HIV envelope protein with alum, as shown in the RV144 trial. Since the efficacy was weak, and previous HIV vaccine trials designed to generate antibody responses failed, we hypothesized that generation of T cell responses would result in improved protection. Thus, we tested the immunogenicity of a similar envelope-based vaccine using a mouse model, with two modifications: a clade C CN54gp140 HIV envelope protein was adjuvanted by the TLR9 agonist IC31®, and the viral vector was the vaccinia strain NYVAC-CN54 expressing HIV envelope gp120. The use of IC31® facilitated immunoglobulin isotype switching, leading to the production of Env-specific IgG2a, as compared to protein with alum alone. Boosting with NYVAC-CN54 resulted in the generation of more robust Th1 T cell responses. Moreover, gp140 prime with IC31® and alum followed by NYVAC-CN54 boost resulted in the formation and persistence of central and effector memory populations in the spleen and an effector memory population in the gut. Our data suggest that this regimen is promising and could improve the protection rate by eliciting strong and long-lasting humoral and cellular immune responses.

  17. Impaired cellular immune response to tetanus toxoid but not to cytomegalovirus in effectively HAART-treated HIV-infected children.

    Science.gov (United States)

    Alsina, Laia; Noguera-Julian, Antoni; Fortuny, Clàudia

    2013-05-07

    Despite of highly active antiretroviral therapy, the response to vaccines in HIV-infected children is poor and short-lived, probably due to a defect in cellular immune responses. We compared the cellular immune response (assessed in terms of IFN-γ production) to tetanus toxoid and to cytomegalovirus in a series of 13 HIV-perinatally-infected children and adolescents with optimal immunovirological response to first line antiretroviral therapy, implemented during chronic infection. A stronger cellular response to cytomegalovirus (11 out of 13 patients) was observed, as compared to tetanus toxoid (1 out of 13; p=0.003). These results suggest that the repeated exposition to CMV, as opposed to the past exposition to TT, is able to maintain an effective antigen-specific immune response in stable HIV-infected pediatric patients and strengthen current recommendations on immunization practices in these children.

  18. Robustness of a Cellular Automata Model for the HIV Infection

    CERN Document Server

    Figueirêdo, P H; Santos, R M Zorzenon dos

    2008-01-01

    An investigation was conducted to study the robustness of the results obtained from the cellular automata model which describes the spread of the HIV infection within lymphoid tissues [R. M. Zorzenon dos Santos and S. Coutinho, Phys. Rev. Lett. 87, 168102 (2001)]. The analysis focussed on the dynamic behavior of the model when defined in lattices with different symmetries and dimensionalities. The results illustrated that the three-phase dynamics of the planar models suffered minor changes in relation to lattice symmetry variations and, while differences were observed regarding dimensionality changes, qualitative behavior was preserved. A further investigation was conducted into primary infection and sensitiveness of the latency period to variations of the model's stochastic parameters over wide ranging values. The variables characterizing primary infection and the latency period exhibited power-law behavior when the stochastic parameters varied over a few orders of magnitude. The power-law exponents were app...

  19. Identification of HIV-1 specific T lymphocyte responses in highly exposed persistently seronegative Chinese

    Institute of Scientific and Technical Information of China (English)

    LIU Hong-wei; SHAO Yi-ming; HONG Kun-xue; MA Jun; YUAN Lin; LIU Sha; CHEN Jian-ping; ZHANG Yuan-zhi; RUAN Yu-hua; XU Jian-qing

    2006-01-01

    Background Studies of highly exposed persistently seronegative (HEPS) individuals may provide valuable information on mechanisms of protection and on vaccine design. Cellular immune responses play a critical role in containing human immunodeficiency virus. However, the cellular immune responses in HEPS individuals have not been thoroughly assessed at the entire viral genome level.Methods Ten HEPS Chinese with a history of frequent penetrative vaginal intercourse (mean frequency, at least once a week), with some unprotected sexual contact occurring in the weeks or days immediately before enrollment, 25 HIV-1 seropositive individuals, 10 HIV-1-seronegative healthy individuals with low-risk sexual behavior and no history suggestive of exposure to HIV-1 infection were enrolled. HIV-1-specific T cell responses were comprehensively analyzed by an interferon- γ Elispot assay against 770 overlapping peptides spanning all HIV-1 proteins.Results HIV-1-specific T-cell responses of interferon- γ secretion were identified in 3 (30%) out of 10 HEPS individuals; the specific cytotoxic T lymphocytes were targeted at Pol (2/10), Env (2/10), and Tat (1/10).HIV-1-specific T-cell responses of interferon- γ secretion were identified in 20 (80%) out of 25 seropositive intravenous drug users (IDUs), revealing that all HIV-1 proteins and protein subunits could serve as targets for HIV-1-specific CD8+ T cell responses with 85% recognizing Gag, 80% recognizing Nef, 75% recognizing Pol,60% recognizing Env, 55% recognizing Vpu, 45% recognizing Vpr, 20% recognizing Vif, 20% recognizing Tat and 15% recognizing Rev in these seropositive individuals. None of the seronegative healthy individuals gave the positive T-cell responses.Conclusions About 30% of HEPS Chinese mounted HIV-1 specific T cell immune responses. Cell-mediated immunity against HIV-1 may be developed through non-productive infections.

  20. Knockdown of cellular RNA helicase DDX3 by short hairpin RNAs suppresses HIV-1 viral replication without inducing apoptosis.

    Science.gov (United States)

    Ishaq, Musarat; Hu, Jiajie; Wu, Xiaoyun; Fu, Qiong; Yang, Yalin; Liu, Qingzhen; Guo, Deyin

    2008-07-01

    The targeting of a cellular co-factor, rather than the HIV-1-specific RNAs, by small interfering RNAs holds promise as the rapid mutational ability of the HIV-1 genome may obviate the potential clinical use of RNAi against this virus. The DEAD-box RNA helicase DDX3 is an essential Rev co-factor in the CRM1-Rev-RRE complex that promotes the export of unspliced and single-spliced HIV-1 RNAs from the nucleus to cytoplasm. In this report, human DDX3 was targeted by specific short hairpin RNAs, and the down-regulation of cell's endogenous DDX3 suppressed the nuclear export of unspliced HIV-1 RNAs but did not affect the cell viability. We further showed that the knockdown of cellular DDX3 could effectively inhibit the replication of HIV-1. Therefore, the current results suggest that the RNA helicase DDX3 may become a potential target by RNAi for future genetic therapy of HIV/AIDS.

  1. Effects of HIV-1 protease on cellular functions and their potential applications in antiretroviral therapy

    Directory of Open Access Journals (Sweden)

    Yang Hailiu

    2012-09-01

    Full Text Available Abstract Human Immunodeficiency Virus Type 1 (HIV-1 protease inhibitors (PIs are the most potent class of drugs in antiretroviral therapies. However, viral drug resistance to PIs could emerge rapidly thus reducing the effectiveness of those drugs. Of note, all current FDA-approved PIs are competitive inhibitors, i.e., inhibitors that compete with substrates for the active enzymatic site. This common inhibitory approach increases the likelihood of developing drug resistant HIV-1 strains that are resistant to many or all current PIs. Hence, new PIs that move away from the current target of the active enzymatic site are needed. Specifically, allosteric inhibitors, inhibitors that prohibit PR enzymatic activities through non-competitive binding to PR, should be sought. Another common feature of current PIs is they were all developed based on the structure-based design. Drugs derived from a structure-based strategy may generate target specific and potent inhibitors. However, this type of drug design can only target one site at a time and drugs discovered by this method are often associated with strong side effects such as cellular toxicity, limiting its number of target choices, efficacy, and applicability. In contrast, a cell-based system may provide a useful alternative strategy that can overcome many of the inherited shortcomings associated with structure-based drug designs. For example, allosteric PIs can be sought using a cell-based system without considering the site or mechanism of inhibition. In addition, a cell-based system can eliminate those PIs that have strong cytotoxic effect. Most importantly, a simple, economical, and easy-to-maintained eukaryotic cellular system such as yeast will allow us to search for potential PIs in a large-scaled high throughput screening (HTS system, thus increasing the chances of success. Based on our many years of experience in using fission yeast as a model system to study HIV-1 Vpr, we propose the use of

  2. Cellular Composition of Cerebrospinal Fluid in HIV-1 Infected and Uninfected Subjects.

    Science.gov (United States)

    Ho, Emily L; Ronquillo, Rollie; Altmeppen, Hermann; Spudich, Serena S; Price, Richard W; Sinclair, Elizabeth

    2013-01-01

    In order to characterize the cellular composition of cerebrospinal fluid (CSF) in a healthy state and in the setting of chronic pleocytosis associated with HIV-1 (HIV) infection, multi-parameter flow cytometry was used to identify and quantitate cellular phenotypes in CSF derived from HIV-uninfected healthy controls and HIV-infected subjects across a spectrum of disease and treatment. CD4+ T cells were the most frequent CSF population and the CD4:CD8 ratio was significantly increased in the CSF compared to blood (p = 0.0232), suggesting preferential trafficking of CD4+ over CD8+ T cells to this compartment. In contrast, in HIV-infection, CD8+ T cells were the major cellular component of the CSF and were markedly increased compared to HIV-uninfected subjects (p<0.001). As with peripheral blood, the CSF CD4:CD8 ratio was reversed in HIV-infected subjects compared to HIV-uninfected subjects. Monocytes, B cells and NK cells were rare in the CSF in both groups, although absolute counts of CSF NK cells and B cells were significantly increased in HIV-infected subjects (p<0.05). Our studies show that T cells are the major cellular component of the CSF in HIV-infected and uninfected subjects. The CSF pleocytosis characteristic of HIV infection involves all lymphocyte subsets we measured, except for CD4+ T cells, but is comprised primarily of CD8+ T cells. The reduced proportion of CD4+ T cells in the CSF may reflect both HIV-related peripheral loss and changes in trafficking patterns in response to HIV infection in the central nervous system.

  3. Cellular Composition of Cerebrospinal Fluid in HIV-1 Infected and Uninfected Subjects.

    Directory of Open Access Journals (Sweden)

    Emily L Ho

    Full Text Available In order to characterize the cellular composition of cerebrospinal fluid (CSF in a healthy state and in the setting of chronic pleocytosis associated with HIV-1 (HIV infection, multi-parameter flow cytometry was used to identify and quantitate cellular phenotypes in CSF derived from HIV-uninfected healthy controls and HIV-infected subjects across a spectrum of disease and treatment. CD4+ T cells were the most frequent CSF population and the CD4:CD8 ratio was significantly increased in the CSF compared to blood (p = 0.0232, suggesting preferential trafficking of CD4+ over CD8+ T cells to this compartment. In contrast, in HIV-infection, CD8+ T cells were the major cellular component of the CSF and were markedly increased compared to HIV-uninfected subjects (p<0.001. As with peripheral blood, the CSF CD4:CD8 ratio was reversed in HIV-infected subjects compared to HIV-uninfected subjects. Monocytes, B cells and NK cells were rare in the CSF in both groups, although absolute counts of CSF NK cells and B cells were significantly increased in HIV-infected subjects (p<0.05. Our studies show that T cells are the major cellular component of the CSF in HIV-infected and uninfected subjects. The CSF pleocytosis characteristic of HIV infection involves all lymphocyte subsets we measured, except for CD4+ T cells, but is comprised primarily of CD8+ T cells. The reduced proportion of CD4+ T cells in the CSF may reflect both HIV-related peripheral loss and changes in trafficking patterns in response to HIV infection in the central nervous system.

  4. HIV-specific cytotoxic T-cell activity in an HIV-exposed but uninfected infant.

    Science.gov (United States)

    Rowland-Jones, S L; Nixon, D F; Aldhous, M C; Gotch, F; Ariyoshi, K; Hallam, N; Kroll, J S; Froebel, K; McMichael, A

    1993-04-03

    The factors necessary for protective immunity against HIV-1 are unknown. Important information about these factors should come from study of people at high risk of HIV infection who have not apparently become infected. Among these are the estimated 60-85% of children who may be exposed in utero or perinatally to HIV-1 but do not become infected. We observed the transient appearance of HIV-specific cytotoxic T-lymphocyte (CTL) activity in a baby born to HIV-1-infected parents, in whom all standard markers of infection remained negative. These findings suggest that HIV-specific CTLs may be a marker for recently exposed, but uninfected, individuals.

  5. Gender-specific HIV policies and programmes at South African ...

    African Journals Online (AJOL)

    Gender-specific HIV policies and programmes at South African workplaces. ... in the fight against HIV/AIDS, thereby helping to achieve equality and dignity. ... prime importance in the spread of HIV/Aids, changes in these accepted gender roles ...

  6. HERV-K–specific T cells eliminate diverse HIV-1/2 and SIV primary isolates

    Science.gov (United States)

    Jones, R. Brad; Garrison, Keith E.; Mujib, Shariq; Mihajlovic, Vesna; Aidarus, Nasra; Hunter, Diana V.; Martin, Eric; John, Vivek M.; Zhan, Wei; Faruk, Nabil F.; Gyenes, Gabor; Sheppard, Neil C.; Priumboom-Brees, Ingrid M.; Goodwin, David A.; Chen, Lianchun; Rieger, Melanie; Muscat-King, Sophie; Loudon, Peter T.; Stanley, Cole; Holditch, Sara J.; Wong, Jessica C.; Clayton, Kiera; Duan, Erick; Song, Haihan; Xu, Yang; SenGupta, Devi; Tandon, Ravi; Sacha, Jonah B.; Brockman, Mark A.; Benko, Erika; Kovacs, Colin; Nixon, Douglas F.; Ostrowski, Mario A.

    2012-01-01

    The genetic diversity of HIV-1 represents a major challenge in vaccine development. In this study, we establish a rationale for eliminating HIV-1–infected cells by targeting cellular immune responses against stable human endogenous retroviral (HERV) antigens. HERV DNA sequences in the human genome represent the remnants of ancient infectious retroviruses. We show that the infection of CD4+ T cells with HIV-1 resulted in transcription of the HML-2 lineage of HERV type K [HERV-K(HML-2)] and the expression of Gag and Env proteins. HERV-K(HML-2)–specific CD8+ T cells obtained from HIV-1–infected human subjects responded to HIV-1–infected cells in a Vif-dependent manner in vitro. Consistent with the proposed mode of action, a HERV-K(HML-2)–specific CD8+ T cell clone exhibited comprehensive elimination of cells infected with a panel of globally diverse HIV-1, HIV-2, and SIV isolates in vitro. We identified a second T cell response that exhibited cross-reactivity between homologous HIV-1-Pol and HERV-K(HML-2)-Pol determinants, raising the possibility that homology between HIV-1 and HERVs plays a role in shaping, and perhaps enhancing, the T cell response to HIV-1. This justifies the consideration of HERV-K(HML-2)–specific and cross-reactive T cell responses in the natural control of HIV-1 infection and for exploring HERV-K(HML-2)–targeted HIV-1 vaccines and immunotherapeutics. PMID:23143309

  7. HIV-1-Specific Antibody Response and Function after DNA Prime and Recombinant Adenovirus 5 Boost HIV Vaccine in HIV-Infected Subjects.

    Science.gov (United States)

    Gach, Johannes S; Gorlani, Andrea; Dotsey, Emmanuel Y; Becerra, Juan C; Anderson, Chase T M; Berzins, Baiba; Felgner, Philip L; Forthal, Donald N; Deeks, Steven G; Wilkin, Timothy J; Casazza, Joseph P; Koup, Richard A; Katlama, Christine; Autran, Brigitte; Murphy, Robert L; Achenbach, Chad J

    2016-01-01

    Little is known about the humoral immune response against DNA prime-recombinant adenovirus 5 (rAd5) boost HIV vaccine among HIV-infected patients on long-term suppressive antiretroviral therapy (ART). Previous studies emphasized cellular immune responses; however, current research suggests both cellular and humoral responses are likely required for a successful therapeutic vaccine. Thus, we aimed to understand antibody response and function induced by vaccination of ART-treated HIV-1-infected patients with immune recovery. All subjects participated in EraMune 02, an open-label randomized clinical trial of ART intensification followed by a six plasmid DNA prime (envA, envB, envC, gagB, polB, nefB) and rAd5 boost HIV vaccine with matching inserts. Antibody binding levels were determined with a recently developed microarray approach. We also analyzed neutralization efficiency and antibody-dependent cellular cytotoxicity (ADCC). We found that the DNA prime-rAd5 boost vaccine induced a significant cross-clade HIV-specific antibody response, which correlated with antibody neutralization efficiency. However, despite the increase in antibody binding levels, the vaccine did not significantly stimulate neutralization or ADCC responses. This finding was also reflected by a lack of change in total CD4+ cell associated HIV DNA in those who received the vaccine. Our results have important implications for further therapeutic vaccine design and administration, especially in HIV-1 infected patients, as boosting of preexisting antibody responses are unlikely to lead to clearance of latent proviruses in the HIV reservoir.

  8. HIV-1 TAR miRNA protects against apoptosis by altering cellular gene expression

    Directory of Open Access Journals (Sweden)

    Meiri Eti

    2009-02-01

    Full Text Available Abstract Background RNA interference is a gene regulatory mechanism that employs small RNA molecules such as microRNA. Previous work has shown that HIV-1 produces TAR viral microRNA. Here we describe the effects of the HIV-1 TAR derived microRNA on cellular gene expression. Results Using a variation of standard techniques we have cloned and sequenced both the 5' and 3' arms of the TAR miRNA. We show that expression of the TAR microRNA protects infected cells from apoptosis and acts by down-regulating cellular genes involved in apoptosis. Specifically, the microRNA down-regulates ERCC1 and IER3, protecting the cell from apoptosis. Comparison to our cloned sequence reveals possible target sites for the TAR miRNA as well. Conclusion The TAR microRNA is expressed in all stages of the viral life cycle, can be detected in latently infected cells, and represents a mechanism wherein the virus extends the life of the infected cell for the purpose of increasing viral replication.

  9. Stem-loop binding protein is a multifaceted cellular regulator of HIV-1 replication

    Science.gov (United States)

    Tucker, Lynne D.; Asara, John M.; Cheruiyot, Collins K.; Lu, Huafei; Wu, Zhijin J.; Newstein, Michael C.; Dooner, Mark S.; Friedman, Jennifer; Lally, Michelle A.; Ramratnam, Bharat

    2016-01-01

    A rare subset of HIV-1–infected individuals is able to maintain plasma viral load (VL) at low levels without antiretroviral treatment. Identifying the mechanisms underlying this atypical response to infection may lead to therapeutic advances for treating HIV-1. Here, we developed a proteomic analysis to compare peripheral blood cell proteomes in 20 HIV-1–infected individuals who maintained either high or low VL with the aim of identifying host factors that impact HIV-1 replication. We determined that the levels of multiple histone proteins were markedly decreased in cohorts of individuals with high VL. This reduction was correlated with lower levels of stem-loop binding protein (SLBP), which is known to control histone metabolism. Depletion of cellular SLBP increased promoter engagement with the chromatin structures of the host gene high mobility group protein A1 (HMGA1) and viral long terminal repeat (LTR), which led to higher levels of HIV-1 genomic integration and proviral transcription. Further, we determined that TNF-α regulates expression of SLBP and observed that plasma TNF-α levels in HIV-1–infected individuals correlated directly with VL levels and inversely with cellular SLBP levels. Our findings identify SLBP as a potentially important cellular regulator of HIV-1, thereby establishing a link between histone metabolism, inflammation, and HIV-1 infection. PMID:27454292

  10. Desarrollo de vacunas contra el virus de la inmunodeficiencia humana tipo 1: Relevancia de la inmunidad celular contra subtipos Development of vaccines for HIV-1: Relevance of subtype-specific cellular immunity

    Directory of Open Access Journals (Sweden)

    Ana María Rodríguez

    2010-12-01

    Full Text Available Han pasado casi 30 años de la detección de los primeros casos de infección con HIV-1 y aún no se ha conseguido desarrollar una vacuna efectiva y segura. A pesar del impacto positivo sobre la pandemia que se ha conseguido gracias a los avances en la terapia antirretroviral (TARV, el HIV/sida sigue constituyendo un grave problema para la salud pública, especialmente en los países en desarrollo, donde es difícil el acceso al tratamiento. En el mundo, 33 millones de personas viven con el virus del sida, mientras que en la Argentina se calcula que habría unos 120 000 infectados. Uno de los desafíos para lograr una vacuna contra el HIV es la variabilidad viral. El grupo M, responsable de la pandemia, se encuentra dividido en 10 subtipos y varios sub-subtipos, además de las 48 formas recombinantes circulantes y más de cien formas recombinantes únicas. La epidemia de HIV en nuestro país es tan compleja como en el resto del mundo, con la co-circulación principalmente de virus pertenecientes al subtipo B y recombinantes BF (CRF12_BF y derivadas. A pesar de la cantidad de trabajos dedicados a la caracterización de la respuesta inmune y al desarrollo de vacunas, no queda claro cuál es el impacto de la variabilidad en la elección del antígeno. Trabajos realizados en nuestro laboratorio demuestran el papel que juega la inmunidad celular con respecto a las variantes recombinantes BF, tanto en humanos como en modelos animales. Estos resultados son de importancia en el desarrollo de futuras vacunas para nuestra región.It has been almost 30 years since the detection of the first HIV-1 cases and yet an effective and safe vaccine has not been developed. Although, advances in antiretroviral therapy (HAART have produced a major impact on the pandemic, and even though HIV/aids remains a major concern for developing countries, where access to therapy is limited. The last report from UNAIDS notified 33 million people living with HIV/aids, worldwide

  11. Structural basis for substrate specificities of cellular deoxyribonucleoside kinases

    DEFF Research Database (Denmark)

    Johansson, K.; Ramaswamy, S.; Ljungcrantz, C.

    2001-01-01

    kinase with ATP at the nucleoside substrate binding site. Compared to the human kinase, the Drosophila kinase has a wider substrate cleft, which may be responsible for the broad substrate specificity of this enzyme. The human deoxyguanosine kinase is highly specific for purine substrates......; this is apparently due to the presence of Arg 118, which provides favorable hydrogen bonding interactions with the substrate. The two new structures provide an explanation for the substrate specificity of cellular deoxyribonucleoside kinases....

  12. Distinct genetic loci control plasma HIV-RNA and cellular HIV-DNA levels in HIV-1 infection: the ANRS Genome Wide Association 01 study.

    Directory of Open Access Journals (Sweden)

    Cyril Dalmasso

    Full Text Available Previous studies of the HIV-1 disease have shown that HLA and Chemokine receptor genetic variants influence disease progression and early viral load. We performed a Genome Wide Association study in a cohort of 605 HIV-1-infected seroconverters for detection of novel genetic factors that influence plasma HIV-RNA and cellular HIV-DNA levels. Most of the SNPs strongly associated with HIV-RNA levels were localised in the 6p21 major histocompatibility complex (MHC region and were in the vicinity of class I and III genes. Moreover, protective alleles for four disease-associated SNPs in the MHC locus (rs2395029, rs13199524, rs12198173 and rs3093662 were strikingly over-represented among forty-five Long Term HIV controllers. Furthermore, we show that the HIV-DNA levels (reflecting the HIV reservoir are associated with the same four SNPs, but also with two additional SNPs on chromosome 17 (rs6503919; intergenic region flanked by the DDX40 and YPEL2 genes and chromosome 8 (rs2575735; within the Syndecan 2 gene. Our data provide evidence that the MHC controls both HIV replication and HIV reservoir. They also indicate that two additional genomic loci may influence the HIV reservoir.

  13. IgG subclass response to HIV in relation to antibody-dependent cellular cytotoxicity at different clinical stages.

    Science.gov (United States)

    Ljunggren, K; Broliden, P A; Morfeldt-Månson, L; Jondal, M; Wahren, B

    1988-01-01

    The anti-HIV IgG subclass response was analysed in sera from different clinical stages and related to virus specific antibody-dependent cellular cytotoxicity (ADCC). IgG1 was found to be the dominant subclass, present in all sera and with similar mean titres at different stages. The number of anti-HIV IgG3 positive sera, measured on whole viral lysate antigen plates, decreased during disease progression from 38% in symptom-free to 7% in AIDS patients. IgG2 and IgG4 subclasses were less prevalent although a slight increase of IgG4 frequency was found in AIDS patients. High IgG1 titres correlated with a positive ADCC reaction but there was no correlation between anti-HIV IgG1 and ADCC titres. Some sera which contained HIV IgG1 as the only subclass were able to mediate an ADCC reaction. In addition, when anti-HIV IgG3 was isolated, by protein A chromatography, no ADCC killing was induced by these antibodies. It is concluded that IgG1 is the major ADCC-active IgG subclass in HIV infected individuals. The lack of correlation between IgG1 and ADCC titres may be explained by a relatively small fraction of IgG1 antibodies mediating ADCC. PMID:3208446

  14. Site-specific hyperphosphorylation of pRb in HIV-induced neurotoxicity.

    Science.gov (United States)

    Akay, C; Lindl, K A; Wang, Y; White, M G; Isaacman-Beck, J; Kolson, D L; Jordan-Sciutto, K L

    2011-06-01

    HIV-Associated Neurocognitive Disorder (HAND) remains a serious complication of HIV infection, despite combined Anti-Retroviral Therapy (cART). Neuronal dysfunction and death are attributed to soluble factors released from activated and/or HIV-infected macrophages. Most of these factors affect the cell cycle machinery, determining cellular outcomes even in the absence of cell division. One of the earliest events in cell cycle activation is hyperphosphorylation of the retinoblastoma protein, pRb (ppRb). We and others have previously shown increased ppRb expression in the CNS of patients with HIV encephalitis (HIVE) and in neurons in an in vitro model of HIV-induced neurodegeneration. However, trophic factors also lead to an increase in neuronal ppRb with an absence of cell death, suggesting that, depending on the stimulus, hyperphosphorylation of pRb can have different outcomes on neuronal fate. pRb has multiple serines and threonines targeted for phosphorylation by distinct kinases, and we hypothesized that different stimuli may target separate sites for phosphorylation. Thus, to determine whether pRb is differentially phosphorylated in response to different stimuli and whether any of these sites is preferentially phosphorylated in association with HIV-induced neurotoxicity, we treated primary rat mixed cortical cultures with trophic factors, BDNF or RANTES, or with the neurotoxic factor, N-methyl-d-aspartate (NMDA), or with supernatants containing factors secreted by HIV-infected monocyte-derived macrophages (HIV-MDM), our in vitro model of HIV-induced neurodegeneration. We found that, while BDNF and RANTES phosphorylated serine807/811 and serine608 in vitro, treatment with HIV-MDM did not, even though these trophic factors are components of HIV-MDM. Rather, HIV-MDM targets a specific phosphorylation site, serine795, of pRb for phosphorylation in vitro and this ppRb isoform is also increased in HIV-infected brains in vivo. Further, overexpression of a

  15. SPECIFIC IMMUNOTHERAPY AND CELLULAR IMMUNITY IN PATIENTS WITH CERVICAL CANCER

    Directory of Open Access Journals (Sweden)

    D. K. Kenbaeva

    2013-01-01

    Full Text Available Cellular mechanisms are quite important immunological components of tumor surveillance, being, however, most vulnerable to influence of different adverse factors, including surgery-associated stress and ionizing radiation. Our study was aimed for assessing specific effects of immunotherapy upon indices of cellular immunity in patients with cervical cancer. Eighty-eight patients with cervical cancer (clinical stage I-IIA, Т1аN0M0-T2aN0M0, who underwent appropriate surgery (for IA stage, or a combined treatment, including surgery gamma-ray teletherapy (IB, IIA stages are under study. The patients were distributed in two groups, depending on the therapy applied. Group 1 included patients subjected to surgical treatment plus and radiation therapy, Group 2 included those patients who were treated according to this protocol, with addition of a specific immunotherapy. Contents of T cells and various CD subpopulations of T-lymphocytes were identified by immunofluorescence techniques. Among patients with cervical cancer at clinical stages IA, IB, IIA, a reliable decrease in cellular immunity indices was registered, both after surgery, and during combined treatment. Introduction of specific immunotherapy to the conventional treatment schedule was associated with increase of cellular immune indices, and, in first line, the antineoplastic mechanisms (e.g., NK’s and NKT cell contents. One should point to a relatively low efficiency of this immunotherapy in combined treatment of patients with cervical cancer at IIA stage.

  16. Polyomavirus specific cellular immunity: from BK-virus-specific cellular immunity to BK-virus-associated nephropathy ?

    Directory of Open Access Journals (Sweden)

    manon edekeyser

    2015-06-01

    Full Text Available In renal transplantation, BK-virus-associated nephropathy has emerged as a major complication, with a prevalence of 5–10% and graft loss in >50% of cases. BK-virus is a member of the Polyomavirus family and rarely induces apparent clinical disease in the general population. However, replication of polyomaviruses, associated with significant organ disease, is observed in patients with acquired immunosuppression, which suggests a critical role for virus-specific cellular immunity to control virus replication and prevent chronic disease. Monitoring of specific immunity combined with viral load could be used to individually assess the risk of viral reactivation and virus control. We review the current knowledge on BK-virus specific cellular immunity and, more specifically, in immunocompromised patients. In the future, immune-based therapies could allow us to treat and prevent BK-virus-associated nephropathy.

  17. 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.

  18. Induction of potent and long-lived antibody and cellular immune responses in the genito-rectal mucosae could be the critical determinant of HIV vaccine efficacy

    Directory of Open Access Journals (Sweden)

    Nadia eChanzu

    2014-05-01

    Full Text Available The field of HIV prevention has indeed progressed in leaps and bounds, but with major limitations of the current prevention and treatment options, the world remains desperate for an HIV vaccine. Sadly, this continues to be elusive as more than 30 years since its discovery there is no licensed HIV vaccine. Research aiming to define immunological biomarkers to accurately predict vaccine efficacy have focussed mainly on systemic immune responses, and as such, studies defining correlates of protection in the genito-rectal mucosae, the primary target site for HIV entry and seeding are sparse. Clearly, difficulties in sampling and analysis of mucosal specimens, as well as their limited size have been a major deterrent in characterizing the type (mucosal antibodies, cytokines, chemokines or CTL, threshold (magnitude, depth and breadth and viral inhibitory capacity of HIV-1 specific immune responses in the genito-rectal mucosae, where they are needed to immediately block HIV acquisition and arrest subsequent virus dissemination. Nevertheless, a few studies document the existence of HIV-specific immune responses in the genito-rectal mucosae of HIV-infected aviremic and viremic controllers, as well as in highly exposed persistently seronegative (HEPS individuals with natural resistance to HIV-1. Some of these responses strongly correlate with protection from HIV acquisition and/or disease progression, thus providing significant clues of the ideal components of an efficacious HIV vaccine. In this article, we provide an overview of the key features of protective immune responses found in HEPS, elite and viremic controllers and discuss how these can be achieved through mucosal immunization. Inevitably, HIV vaccine development research will have to consider strategies which elicit potent antibody and cellular immune responses within the genito-rectal mucosae or induction of systemic immune cells with an inherent potential to home and persist at mucosal sites

  19. Tunable CD44-specific cellular retargeting with hyaluronic acid nanoshells

    DEFF Research Database (Denmark)

    Ebbesen, Morten F.; Olesen, Morten T. J.; Gjelstrup, Mikkel C.;

    2014-01-01

    Purpose In this work we specifically investigate the molecular weight (Mw) dependent combinatorial properties of hyaluronic acid (HA) for exhibiting stealth and targeting properties using different Mw HA nanoshells to tune nanoparticle retargeting to CD44-expressing cancer cells. Methods HA...... that indicates an extended and nonconstricted HA polymer surface. Reduced non-specific particle interaction in CD44- cells was shown for all HA nanoshells but CD44-dependent cellular retargeting and internalization in CD44+ cells was highly dependent on the coating HA Mw properties. Conclusion The combination...

  20. HIV Specific Humoral Immune Response in Rio de Janeiro, Brazil

    Directory of Open Access Journals (Sweden)

    Bongertz V

    1998-01-01

    Full Text Available Efforts to characterize HIV-1 polymorphism and anti-HIV immune response are being made in areas where anti-HIV/AIDS vaccines are to be employed. Anti-HIV-1 humoral immune response is being studied in infected individuals resident in Rio de Janeiro, in distinct cohorts involving recent seroconvertors, pregnant women or intravenous drug users (IDU. Comparative analyses of specificity of antibody response towards epitopes important for anti-HIV-1 immune response indicate quantitative differences between cohorts, with an exceptionally strong response in IDUs and weakest response in pregnant women. However, a comparative analysis between pregnant women cohorts from Rio de Janeiro and Rio Grande do Sul indicated an even lower response (with exception of the anti-V3-C clade peptide recognition for the southern cohort. Studies analysing the immune function of the humoral response indicate a quite elevated occurrence of antibodies capable of neutralizing heterologous primary HIV-1 isolates from Rio de Janeiro. Attempts to correlate seroreactivity with HIV-1 neutralization with respect to HIV-1 polymorphism were not very successfull: while the Brazilian B clade B" variant could be recognized by binding assays, no significant distinction of HIV-1 clades/variants was observed in viral neutralization assays.

  1. Cellular immune responses in HIV-negative immunodeficiency with anti-interferon-γ antibodies and opportunistic intracellular microorganisms.

    Directory of Open Access Journals (Sweden)

    Jiraprapa Wipasa

    Full Text Available BACKGROUND: Cell-mediated immunity plays a crucial role in resistance to intracellular infection. We previously reported antibodies against interferon-gamma (IFN-γ in HIV- negative (HIV- patients with acquired immunodeficiency presenting with repeated episodes of disseminated infection caused by uncommon opportunistic intracellular fungal, bacterial, and viral pathogens. This follow-up study aimed to investigate cellular immune responses in these unusual patients. METHODS: Twenty HIV- patients presenting with ≥2 episodes of culture- or histopathologic-proven opportunistic infections were enrolled along with age- and sex-matched controls comprised of 20 HIV+ patients plus 20 healthy adults. Monocyte phenotyping and intracellular cytokine production were determined by staining with specific antibodies followed by flow cytometry. Anti-interferon-γ antibodies were measured by enzyme-linked immunosorbent assay, and inducible nitric oxide synthase by reverse-transcription polymerase chain reaction. RESULTS: There were no differences among cases, HIV+, and healthy controls in the percentage of monocytes, or CD68 and HLA-DR expression on their surfaces. FcR1 (CD119 expression on monocytes was significantly higher in cases than in HIV+ (p<0.05 and healthy controls (p<0.01, suggesting the presence of activated monocytes in the circulation. Interleukin (IL-2 and tumor necrosis factor (TNF-α production in CD4 cells were significantly lower in cases than in healthy controls (p<0.01 and p<0.001, respectively. CD8 production of TNF-α among cases was significantly lower than that of healthy controls (p<0.05. CONCLUSION: Immunodeficiency in HIV- individuals with repeated infections with intracellular pathogens may be associated with one or more of the abnormal immune responses reflected by the reduced production of both IL-2 by CD4 T cells and TNF-α by CD4 T cells and CD8 T cells, as well as presence of anti-IFN-γ antibody, as previously reported.

  2. Alternative effector-function profiling identifies broad HIV-specific T-cell responses in highly HIV-exposed individuals who remain uninfected.

    Science.gov (United States)

    Ruiz-Riol, Marta; Llano, Anuska; Ibarrondo, Javier; Zamarreño, Jennifer; Yusim, Karina; Bach, Vanessa; Mothe, Beatriz; Perez-Alvarez, Susana; Fernandez, Marco A; Requena, Gerard; Meulbroek, Michael; Pujol, Ferran; Leon, Agathe; Cobarsi, Patricia; Korber, Bette T; Clotet, Bonaventura; Ganoza, Carmela; Sanchez, Jorge; Coll, Josep; Brander, Christian

    2015-03-15

    The characterization of host immune responses to human immunodeficiency virus (HIV) in HIV controllers and individuals with high exposure but seronegativity to HIV (HESN) is needed to guide the development of effective preventive and therapeutic vaccine candidates. However, several technical hurdles severely limit the definition of an effective virus-specific T-cell response. By using a toggle-peptide approach, which takes HIV sequence diversity into account, and a novel, boosted cytokine staining/flow cytometry strategy, we here describe new patterns of T-cell responses to HIV that would be missed by standard assays. Importantly, this approach also allows detection of broad and strong virus-specific T-cell responses in HESN individuals that are characterized by a T-helper type 1 cytokine-like effector profile and produce cytokines that have been associated with potential control of HIV infection, including interleukin 10, interleukin 13, and interleukin 22. These results establish a novel approach to improve the current understanding of HIV-specific T-cell immunity and identify cellular immune responses and individual cytokines as potential markers of relative HIV resistance. As such, the findings also help develop similar strategies for more-comprehensive assessments of host immune responses to other human infections and immune-mediated disorders.

  3. Engineering HIV-Specific Immunity with Chimeric Antigen Receptors.

    Science.gov (United States)

    Kitchen, Scott G; Zack, Jerome A

    2016-12-01

    HIV remains a highly important public health and clinical issue despite many recent advances in attempting to develop a cure, which has remained elusive for most people infected with HIV. HIV disease can be controlled with pharmacologic therapies; however, these treatments are expensive, may have severe side effects, and are not curative. Consequently, an improved means to control or eliminate HIV replication is needed. Cytotoxic T lymphocytes (CTLs) play a critical role in controlling viral replication and are an important part in the ability of the immune response to eradicate most viral infections. There are considerable efforts to enhance CTL responses in HIV-infected individuals in hopes of providing the immune response with armaments to more effectively control viral replication. In this review, we discuss some of these efforts and focus on the development of a gene therapy-based approach to engineer hematopoietic stem cells with an HIV-1-specific chimeric antigen receptor, which seeks to provide an inexhaustible source of HIV-1-specific immune cells that are MHC unrestricted and superior to natural antiviral T cell responses. These efforts provide the basis for further development of T cell functional enhancement to target and treat chronic HIV infection in hopes of eradicating the virus from the body.

  4. Translation of Pur-α is targeted by cellular miRNAs to modulate the differentiation-dependent susceptibility of monocytes to HIV-1 infection.

    Science.gov (United States)

    Shen, Chan-Juan; Jia, Yan-Hui; Tian, Ren-Rong; Ding, Ming; Zhang, Chiyu; Wang, Jian-Hua

    2012-11-01

    The postentry restriction of HIV-1 replication in monocytes can be relieved when they differentiate to dendritic cells (DCs) or macrophages. Multiple mechanisms have been proposed to interpret the differentiation-dependent susceptibility of monocytes to HIV-1 infection, and the absence of host-cell-encoded essential factors for HIV-1 completing the life cycle may provide an explanation. We have analyzed the gene expression profile in monocytes by mRNA microarray and compared it with that of differentiated DCs. We demonstrated that purine-rich element binding protein α (Pur-α), a host-cell-encoded ubiquitous, sequence-specific DNA- and RNA-binding protein, showed inadequate expression in monocytes, and the translation of Pur-α mRNA was repressed by cell-expressed microRNA (miRNA). These Pur-α-targeted miRNAs modulated the differentiation-dependent susceptibility of monocytes/DCs to HIV-1 infection, because rescue of Pur-α expression by transfection of miRNA inhibitors relieved the restriction of HIV-1 infection in monocytes, and ectopic input of miRNA mimics significantly reduced HIV-1 infection of monocyte-derived DCs (MDDCs). Collectively, our data emphasized that inadequate host factors contribute to HIV-1 restriction in monocytes, and cellular miRNAs modulate differentiation-dependent susceptibility of host cells to HIV-1 infection. Elaboration of HIV-1 restriction in host cells facilitates our understanding of viral pathogenesis and the search for a new antiviral strategy.

  5. Differential in vitro inhibitory activity against HIV-1 of alpha-(1-3- and alpha-(1-6-D-mannose specific plant lectins : Implication for microbicide development

    Directory of Open Access Journals (Sweden)

    Balzarini Jan

    2007-06-01

    Full Text Available Abstract Background Plant lectins such as Galanthus nivalis agglutinin (GNA and Hippeastrum hybrid agglutinin (HHA are natural proteins able to link mannose residues, and therefore inhibit HIV-target cell interactions. Plant lectins are candidate for microbicide development. Objective To evaluate the activity against HIV of the mannose-specific plant lectins HHA and GNA at the cellular membrane level of epithelial cells and monocyte-derived dendritic cells (MDDC, two potential target cells of HIV at the genital mucosal level. Methods The inhibitory effects of HHA and GNA were evaluated on HIV adsorption to genital epithelial HEC-1A cell line, on HIV transcytosis throughout a monolayer of polarized epithelial HEC-1A cells, on HIV adsorption to MDDC and on transfer of HIV from MDDC to autologous T lymphocytes. Results HHA faintly inhibited attachment to HEC-1A cells of the R5-tropic HIV-1Ba-L strain, in a dose-dependent manner, whereas GNA moderately inhibited HIV adsorption in the same context, but only at high drug doses. Only HHA, but not GNA, inhibited HIV-1JR-CSF transcytosis in a dose-dependent manner. By confocal microscopy, HHA, but not GNA, was adsorbed at the epithelial cell surface, suggesting that HHA interacts specifically with receptors mediating HIV-1 transcytosis. Both plant lectins partially inhibited HIV attachment to MDDC. HHA inhibited more efficiently the transfer of HIV from MDDC to T cell, than GNA. Both HHA and GNA lacked toxicity below 200 μg/ml irrespective the cellular system used and do not disturb the monolayer integrity of epithelial cells. Conclusion These observations demonstrate higher inhibitory activities of the lectin plant HHA by comparison to GNA, on HIV adsorption to HEC-1A cell line, HIV transcytosis through HEC-1A cell line monolayer, HIV adsorption to MDDC and HIV transfer from MDDC to T cells, highlighting the potential interest of HHA as effective microbicide against HIV.

  6. HIV infection and specific mucosal immunity: workshop 4B.

    Science.gov (United States)

    Challacombe, S J; Fidel, P L; Tugizov, S; Tao, L; Wahl, S M

    2011-04-01

    Most HIV infections are transmitted across mucosal epithelium. An area of fundamental importance is understanding the role of innate and specific mucosal immunity in susceptibility or protection against HIV infection, as well as the effect of HIV infection on mucosal immunity, which leads to increased susceptibility to bacterial, fungal, and viral infections of oral and other mucosae. This workshop attempted to address 5 basic issues-namely, HIV acquisition across mucosal surfaces, innate and adaptive immunity in HIV resistance, antiviral activity of breast milk as a model mucosal fluid, neutralizing immunoglobulin A antibodies against HIV, and progress toward a mucosal vaccine against HIV. The workshop attendants agreed that progress had been made in each area covered, with much recent information. However, these advances revealed how little work had been performed on stratified squamous epithelium compared with columnar epithelium, and the attendants identified several important biological questions that had not been addressed. It is increasingly clear that innate immunity has an important biological role, although basic understanding of the mechanisms of normal homeostasis is still being investigated. Application of the emerging knowledge was lacking with regard to homeostatic mucosal immunity to HIV and its role in changing this homeostasis. With regard to breast milk, a series of studies have demonstrated the differences between transmitters and nontransmitters, although whether these findings could be generalized to other secretions such as saliva was less clear. Important progress toward an oral mucosal HIV vaccine has been made, demonstrating proof of principle for administering vaccine candidates into oral lymphoid tissues to trigger anti-HIV local and systemic immune responses. Similarly, experimental data emphasized the central role of neutralizing antibodies to prevent HIV infection via mucosal routes.

  7. DDX5 facilitates HIV-1 replication as a cellular co-factor of Rev.

    Directory of Open Access Journals (Sweden)

    Xiuxia Zhou

    Full Text Available HIV-1 Rev plays an important role in the late phase of HIV-1 replication, which facilitates export of unspliced viral mRNAs from the nucleus to cytoplasm in infected cells. Recent studies have shown that DDX1 and DDX3 are co-factors of Rev for the export of HIV-1 transcripts. In this report, we have demonstrated that DDX5 (p68, which is a multifunctional DEAD-box RNA helicase, functions as a new cellular co-factor of HIV-1 Rev. We found that DDX5 affects Rev function through the Rev-RRE axis and subsequently enhances HIV-1 replication. Confocal microscopy and co-immunoprecipitation analysis indicated that DDX5 binds to Rev and this interaction is largely dependent on RNA. If the DEAD-box motif of DDX5 is mutated, DDX5 loses almost all of its ability to bind to Rev, indicating that the DEAD-box motif of DDX5 is required for the interaction between DDX5 and Rev. Our data indicate that interference of DDX5-Rev interaction could reduce HIV-1 replication and potentially provide a new molecular target for anti-HIV-1 therapeutics.

  8. Reverse Transcriptase and Cellular Factors: Regulators of HIV-1 Reverse Transcription

    Directory of Open Access Journals (Sweden)

    David Harrich

    2009-11-01

    Full Text Available There is ample evidence that synthesis of HIV-1 proviral DNA from the viral RNA genome during reverse transcription requires host factors. However, only a few cellular proteins have been described in detail that affect reverse transcription and interact with reverse transcriptase (RT. HIV-1 integrase is an RT binding protein and a number of IN-binding proteins including INI1, components of the Sin3a complex, and Gemin2 affect reverse transcription. In addition, recent studies implicate the cellular proteins HuR, AKAP149, and DNA topoisomerase I in reverse transcription through an interaction with RT. In this review we will consider interactions of reverse transcription complex with viral and cellular factors and how they affect the reverse transcription process.

  9. HIV-1 Reverse Transcriptase based assay to determine cellular dNTP concentrations

    Science.gov (United States)

    Hollenbaugh, Joseph A.; Kim, Baek

    2016-01-01

    Summary Deoxynucleoside triphosphates (dNTPs) are the building blocks of DNA and their biosynthesis are tightly regulated in the cell. HPLC-MS and enzyme-based methods are currently employed to determine dNTP concentrations from cellular extracts. Here, we describe a highly efficient, HIV-1 reverse transcriptase (RT)-based assay to quantitate dNTP concentrations. The assay is based on the ability of HIV-1 RT to function at very low dNTP concentrations, thus providing for the high sensitivity of detection. PMID:26714705

  10. Cell-specific RNA aptamer against human CCR5 specifically targets HIV-1 susceptible cells and inhibits HIV-1 infectivity.

    Science.gov (United States)

    Zhou, Jiehua; Satheesan, Sangeetha; Li, Haitang; Weinberg, Marc S; Morris, Kevin V; Burnett, John C; Rossi, John J

    2015-03-19

    The C-C chemokine receptor type 5 (CCR5) is a receptor expressed by T cells and macrophages that serves as a coreceptor for macrophage-tropic HIV-1. Loss of CCR5 is associated with resistance to HIV-1. Here, we combine the live-cell-based SELEX with high-throughput sequencing technology to generate CCR5 RNA aptamers capable of specifically targeting HIV-1 susceptible cells (as small interfering RNA [siRNA] delivery agent) and inhibiting HIV-1 infectivity (as antiviral agent) via block of the CCR5 required for HIV-1 to enter cells. One of the best candidates, G-3, efficiently bound and was internalized into human CCR5-expressing cells. The G-3 specifically neutralized R5 virus infection in primary peripheral blood mononuclear cells, and in vivo generated human CD4(+) T cells with a nanomolar inhibitory concentration 50%. G-3 was also capable of transferring functional siRNAs to CCR5-expressing cells. Collectively, the cell-specific, internalizing, CCR5-targeted aptamers and aptamer-siRNA conjugates offer promise for overcoming some of the current challenges of drug resistance in HIV-1 by providing cell-type- or tissue-specific delivery of various therapeutic moieties.

  11. HIV-2 neutralization by intact V3-specific Fab fragments

    Directory of Open Access Journals (Sweden)

    Sourial Samer

    2008-08-01

    Full Text Available Abstract The V3 region of both HIV-1 gp120 and HIV-2 gp125 surface glycoprotein has been described as a target for neutralizing antibodies. In this study a conformation-sensitive (3C4 and a linear site-specific (7C8 anti-HIV-2 V3 monoclonal antibody (mAb were characterized. The neutralization capacity of the purified mAbs and their respective papain-generated Fab fragments was analyzed. The Fabs were further characterized by sequence analysis. Our results demonstrate that neither purified mAbs were capable of neutralizing HIV-2, while intact Fab fragments from both mAbs blocked in vitro infection of HIV-2 isolates. Moreover, the conformation sensitive 3C4 Fab neutralized both subtype A and B HIV-2 isolates and SIVsm. Sequence analysis of the hypervariable regions of 3C4 Fab and 7C8 Fab revealed that the third CDR of the heavy chain (CDRH3 of the antibodies was not as long as many of the previously characterized neutralizing antibodies. Our findings suggest that whole 7C8 and 3C4 mAbs are sterically hindered from neutralizing HIV-2, whereas the smaller size of Fab fragments enables access to the V3 region on the virion surface.

  12. Silibinin inhibits HIV-1 infection by reducing cellular activation and proliferation.

    Science.gov (United States)

    McClure, Janela; Lovelace, Erica S; Elahi, Shokrollah; Maurice, Nicholas J; Wagoner, Jessica; Dragavon, Joan; Mittler, John E; Kraft, Zane; Stamatatos, Leonidas; Stamatatos, Leonidis; Horton, Helen; De Rosa, Stephen C; Coombs, Robert W; Polyak, Stephen J

    2012-01-01

    Purified silymarin-derived natural products from the milk thistle plant (Silybum marianum) block hepatitis C virus (HCV) infection and inhibit T cell proliferation in vitro. An intravenous formulation of silibinin (SIL), a major component of silymarin, displays anti-HCV effects in humans and also inhibits T-cell proliferation in vitro. We show that SIL inhibited replication of HIV-1 in TZM-bl cells, PBMCs, and CEM cells in vitro. SIL suppression of HIV-1 coincided with dose-dependent reductions in actively proliferating CD19+, CD4+, and CD8+ cells, resulting in fewer CD4+ T cells expressing the HIV-1 co-receptors CXCR4 and CCR5. SIL inhibition of T-cell growth was not due to cytotoxicity measured by cell cycle arrest, apoptosis, or necrosis. SIL also blocked induction of the activation markers CD38, HLA-DR, Ki67, and CCR5 on CD4+ T cells. The data suggest that SIL attenuated cellular functions involved in T-cell activation, proliferation, and HIV-1 infection. Silymarin-derived compounds provide cytoprotection by suppressing virus infection, immune activation, and inflammation, and as such may be relevant for both HIV mono-infected and HIV/HCV co-infected subjects.

  13. Silibinin inhibits HIV-1 infection by reducing cellular activation and proliferation.

    Directory of Open Access Journals (Sweden)

    Janela McClure

    Full Text Available Purified silymarin-derived natural products from the milk thistle plant (Silybum marianum block hepatitis C virus (HCV infection and inhibit T cell proliferation in vitro. An intravenous formulation of silibinin (SIL, a major component of silymarin, displays anti-HCV effects in humans and also inhibits T-cell proliferation in vitro. We show that SIL inhibited replication of HIV-1 in TZM-bl cells, PBMCs, and CEM cells in vitro. SIL suppression of HIV-1 coincided with dose-dependent reductions in actively proliferating CD19+, CD4+, and CD8+ cells, resulting in fewer CD4+ T cells expressing the HIV-1 co-receptors CXCR4 and CCR5. SIL inhibition of T-cell growth was not due to cytotoxicity measured by cell cycle arrest, apoptosis, or necrosis. SIL also blocked induction of the activation markers CD38, HLA-DR, Ki67, and CCR5 on CD4+ T cells. The data suggest that SIL attenuated cellular functions involved in T-cell activation, proliferation, and HIV-1 infection. Silymarin-derived compounds provide cytoprotection by suppressing virus infection, immune activation, and inflammation, and as such may be relevant for both HIV mono-infected and HIV/HCV co-infected subjects.

  14. Proteoform-Specific Insights into Cellular Proteome Regulation.

    Science.gov (United States)

    Norris, Emma L; Headlam, Madeleine J; Dave, Keyur A; Smith, David D; Bukreyev, Alexander; Singh, Toshna; Jayakody, Buddhika A; Chappell, Keith J; Collins, Peter L; Gorman, Jeffrey J

    2016-10-01

    Knowledge regarding compositions of proteomes at the proteoform level enhances insights into cellular phenotypes. A strategy is described herein for discovery of proteoform-specific information about cellular proteomes. This strategy involved analysis of data obtained by bottom-up mass spectrometry of multiple protein OGE separations on a fraction by fraction basis. The strategy was exemplified using five matched sets of lysates of uninfected and human respiratory syncytial virus-infected A549 cells. Template matching demonstrated that 67.3% of 10475 protein profiles identified focused to narrow pI windows indicative of efficacious focusing. Furthermore, correlation between experimental and theoretical pI gradients indicated reproducible focusing. Based on these observations a proteoform profiling strategy was developed to identify proteoforms, detect proteoform diversity and discover potential proteoform regulation. One component of this strategy involved examination of the focusing profiles for protein groups. A novel concordance analysis facilitated differentiation between proteoforms, including proteoforms generated by alternate splicing and proteolysis. Evaluation of focusing profiles and concordance analysis were applicable to cells from a single and/or multiple biological states. Statistical analyses identified proteoform variation between biological states. Regulation relevant to cellular responses to human respiratory syncytial virus was revealed. Western blotting and Protomap analyses validated the proteoform regulation. Discovery of STAT1, WARS, MX1, and HSPB1 proteoform regulation by human respiratory syncytial virus highlighted the impact of the profiling strategy. Novel truncated proteoforms of MX1 were identified in infected cells and phosphorylation driven regulation of HSPB1 proteoforms was correlated with infection. The proteoform profiling strategy is generally applicable to investigating interactions between viruses and host cells and the

  15. Preferential infection and depletion of Mycobacterium tuberculosis-specific CD4 T cells after HIV-1 infection.

    Science.gov (United States)

    Geldmacher, Christof; Ngwenyama, Njabulo; Schuetz, Alexandra; Petrovas, Constantinos; Reither, Klaus; Heeregrave, Edwin J; Casazza, Joseph P; Ambrozak, David R; Louder, Mark; Ampofo, William; Pollakis, Georgios; Hill, Brenna; Sanga, Erica; Saathoff, Elmar; Maboko, Leonard; Roederer, Mario; Paxton, William A; Hoelscher, Michael; Koup, Richard A

    2010-12-20

    HIV-1 infection results in the progressive loss of CD4 T cells. In this study, we address how different pathogen-specific CD4 T cells are affected by HIV infection and the cellular parameters involved. We found striking differences in the depletion rates between CD4 T cells to two common opportunistic pathogens, cytomegalovirus (CMV) and Mycobacterium tuberculosis (MTB). CMV-specific CD4 T cells persisted after HIV infection, whereas MTB-specific CD4 T cells were depleted rapidly. CMV-specific CD4 T cells expressed a mature phenotype and produced very little IL-2, but large amounts of MIP-1β. In contrast, MTB-specific CD4 T cells were less mature, and most produced IL-2 but not MIP-1β. Staphylococcal enterotoxin B-stimulated IL-2-producing cells were more susceptible to HIV infection in vitro than MIP-1β-producing cells. Moreover, IL-2 production was associated with expression of CD25, and neutralization of IL-2 completely abrogated productive HIV infection in vitro. HIV DNA was found to be most abundant in IL-2-producing cells, and least abundant in MIP-1β-producing MTB-specific CD4 T cells from HIV-infected subjects with active tuberculosis. These data support the hypothesis that differences in function affect the susceptibility of pathogen-specific CD4 T cells to HIV infection and depletion in vivo, providing a potential mechanism to explain the rapid loss of MTB-specific CD4 T cells after HIV infection.

  16. Identification of peptides from human pathogens able to cross-activate an HIV-1-gag-specific CD4+ T cell clone.

    Science.gov (United States)

    Venturini, Sara; Allicotti, Gina; Zhao, Yindong; Simon, Richard; Burton, Dennis R; Pinilla, Clemencia; Poignard, Pascal

    2006-01-01

    Antigen recognition by T cells is degenerate both at the MHC and the TCR level. In this study, we analyzed the cross-reactivity of a human HIV-1 gag p24-specific CD4(+) T cell clone obtained from an HIV-1-seronegative donor using a positional scanning synthetic combinatorial peptide library (PS-SCL)-based biometrical analysis. A number of decapeptides able to activate the HIV-1 gag-specific clone were identified and shown to correspond to sequences found in other human pathogens. Two of these peptides activated the T cell clone with the same stimulatory potency as the original HIV-1 gag p24 peptide. These findings show that an HIV-1-specific human T helper clone can react efficiently with peptides from other pathogens and suggest that cellular immune responses identified as being specific for one human pathogen (HIV-1) could arise from exposure to other pathogens.

  17. Inhibition of HIV by Legalon-SIL is independent of its effect on cellular metabolism

    Energy Technology Data Exchange (ETDEWEB)

    McClure, Janela [Department of Laboratory Medicine, University of Washington, Seattle, WA (United States); Margineantu, Daciana H. [Department of Clinical Research, Fred Hutchinson Cancer Research Center, Seattle, WA (United States); Sweet, Ian R. [Department of Medicine (Division of Metabolism, Endocrinology, and Nutrition), University of Washington, Seattle, WA (United States); Polyak, Stephen J., E-mail: polyak@uw.edu [Department of Laboratory Medicine, University of Washington, Seattle, WA (United States); Department of Global Health, University of Washington, Seattle, WA (United States)

    2014-01-20

    In this report, we further characterized the effects of silibinin (SbN), derived from milk thistle extract, and Legalon-SIL (SIL), a water-soluble derivative of SbN, on T cell metabolism and HIV infection. We assessed the effects of SbN and SIL on peripheral blood mononuclear cells (PBMC) and CEM-T4 cells in terms of cellular growth, ATP content, metabolism, and HIV infection. SIL and SbN caused a rapid and reversible (upon removal) decrease in cellular ATP levels, which was associated with suppression of mitochondrial respiration and glycolysis. SbN, but not SIL inhibited glucose uptake. Exposure of T cells to SIL (but not SbN or metabolic inhibitors) during virus adsorption blocked HIV infection. Thus, both SbN and SIL rapidly perturb T cell metabolism in vitro, which may account for its anti-inflammatory and anti-proliferative effects that arise with prolonged exposure of cells. However, the metabolic effects are not involved in SIL's unique ability to block HIV entry. - Highlights: • Silibinin (SbN) and Legalon-SIL (SIL) are cytoprotective mixtures of natural products. • SbN and SIL reduce T cell oxidative phosphorylation and glycolysis in vitro. • SIL but not SbN blocks entry of multiple HIV isolates into T cells in vitro. • SIL's suppression of HIV appears independent of its effects on T cell metabolism. • Metabolic effects of SIL and SbN may be relevant in inflammatory diseases.

  18. Inhibition of HIV by Legalon-SIL is independent of its effect on cellular metabolism.

    Science.gov (United States)

    McClure, Janela; Margineantu, Daciana H; Sweet, Ian R; Polyak, Stephen J

    2014-01-20

    In this report, we further characterized the effects of silibinin (SbN), derived from milk thistle extract, and Legalon-SIL (SIL), a water-soluble derivative of SbN, on T cell metabolism and HIV infection. We assessed the effects of SbN and SIL on peripheral blood mononuclear cells (PBMC) and CEM-T4 cells in terms of cellular growth, ATP content, metabolism, and HIV infection. SIL and SbN caused a rapid and reversible (upon removal) decrease in cellular ATP levels, which was associated with suppression of mitochondrial respiration and glycolysis. SbN, but not SIL inhibited glucose uptake. Exposure of T cells to SIL (but not SbN or metabolic inhibitors) during virus adsorption blocked HIV infection. Thus, both SbN and SIL rapidly perturb T cell metabolism in vitro, which may account for its anti-inflammatory and anti-proliferative effects that arise with prolonged exposure of cells. However, the metabolic effects are not involved in SIL's unique ability to block HIV entry.

  19. Cellular HIV-1 DNA levels in drug sensitive strains are equivalent to those in drug resistant strains in newly-diagnosed patients in Europe.

    Directory of Open Access Journals (Sweden)

    Victoria L Demetriou

    Full Text Available BACKGROUND: HIV-1 genotypic drug resistance is an important threat to the success of antiretroviral therapy and transmitted resistance has reached 9% prevalence in Europe. Studies have demonstrated that HIV-1 DNA load in peripheral blood mononuclear cells (PBMC have a predictive value for disease progression, independently of CD4 counts and plasma viral load. METHODOLOGY/PRINCIPAL FINDINGS: Molecular-beacon-based real-time PCR was used to measure HIV-1 second template switch (STS DNA in PBMC in newly-diagnosed HIV-1 patients across Europe. These patients were representative for the HIV-1 epidemic in the participating countries and were carrying either drug-resistant or sensitive viral strains. The assay design was improved from a previous version to specifically detect M-group HIV-1 and human CCR5 alleles. The findings resulted in a median of 3.32 log(10 HIV-1 copies/10(6 PBMC and demonstrated for the first time no correlation between cellular HIV-1 DNA load and transmitted drug-resistance. A weak association between cellular HIV-1 DNA levels with plasma viral RNA load and CD4(+ T-cell counts was also reconfirmed. Co-receptor tropism for 91% of samples, whether or not they conferred resistance, was CCR5. A comparison of pol sequences derived from RNA and DNA, resulted in a high similarity between the two. CONCLUSIONS/SIGNIFICANCE: An improved molecular-beacon-based real-time PCR assay is reported for the measurement of HIV-1 DNA in PBMC and has investigated the association between cellular HIV-1 DNA levels and transmitted resistance to antiretroviral therapy in newly-diagnosed patients from across Europe. The findings show no correlation between these two parameters, suggesting that transmitted resistance does not impact disease progression in HIV-1 infected individuals. The CCR5 co-receptor tropism predominance implies that both resistant and non-resistant strains behave similarly in early infection. Furthermore, a correlation found between RNA

  20. HIV-1 evades innate immune recognition through specific cofactor recruitment

    Science.gov (United States)

    Rasaiyaah, Jane; Tan, Choon Ping; Fletcher, Adam J.; Price, Amanda J.; Blondeau, Caroline; Hilditch, Laura; Jacques, David A.; Selwood, David L.; James, Leo C.; Noursadeghi, Mahdad; Towers, Greg J.

    2013-11-01

    Human immunodeficiency virus (HIV)-1 is able to replicate in primary human macrophages without stimulating innate immunity despite reverse transcription of genomic RNA into double-stranded DNA, an activity that might be expected to trigger innate pattern recognition receptors. We reasoned that if correctly orchestrated HIV-1 uncoating and nuclear entry is important for evasion of innate sensors then manipulation of specific interactions between HIV-1 capsid and host factors that putatively regulate these processes should trigger pattern recognition receptors and stimulate type 1 interferon (IFN) secretion. Here we show that HIV-1 capsid mutants N74D and P90A, which are impaired for interaction with cofactors cleavage and polyadenylation specificity factor subunit 6 (CPSF6) and cyclophilins (Nup358 and CypA), respectively, cannot replicate in primary human monocyte-derived macrophages because they trigger innate sensors leading to nuclear translocation of NF-κB and IRF3, the production of soluble type 1 IFN and induction of an antiviral state. Depletion of CPSF6 with short hairpin RNA expression allows wild-type virus to trigger innate sensors and IFN production. In each case, suppressed replication is rescued by IFN-receptor blockade, demonstrating a role for IFN in restriction. IFN production is dependent on viral reverse transcription but not integration, indicating that a viral reverse transcription product comprises the HIV-1 pathogen-associated molecular pattern. Finally, we show that we can pharmacologically induce wild-type HIV-1 infection to stimulate IFN secretion and an antiviral state using a non-immunosuppressive cyclosporine analogue. We conclude that HIV-1 has evolved to use CPSF6 and cyclophilins to cloak its replication, allowing evasion of innate immune sensors and induction of a cell-autonomous innate immune response in primary human macrophages.

  1. Synthetic consensus HIV-1 DNA induces potent cellular immune responses and synthesis of granzyme B, perforin in HIV infected individuals.

    Science.gov (United States)

    Morrow, Matthew P; Tebas, Pablo; Yan, Jian; Ramirez, Lorenzo; Slager, Anna; Kraynyak, Kim; Diehl, Malissa; Shah, Divya; Khan, Amir; Lee, Jessica; Boyer, Jean; Kim, J Joseph; Sardesai, Niranjan Y; Weiner, David B; Bagarazzi, Mark L

    2015-03-01

    This study evaluated the safety and immunogenicity of PENNVAX-B in 12 HIV infected individuals. PENNVAX-B is a combination of three optimized synthetic plasmids encoding for multiclade HIV Gag and Pol and a consensus CladeB Env delivered by electroporation. HIV infected individuals whose virus was effectively suppressed using highly active antiretroviral therapy (HAART) received PENNVAX-B DNA followed by electroporation with CELLECTRA-5P at study weeks 0, 4, 8, and 16. Local administration site and systemic reactions to PENNVAX-B were recorded after each treatment along with any adverse events. Pain of the treatment procedure was assessed using a Visual Analog Scale. Whole PBMCs were isolated for use in IFN ELISpot and Flow Cytometric assays. PENNVAX-B was generally safe and well tolerated. Overall, the four dose regimen was not associated with any serious adverse events or severe local or systemic reactions. A rise in antigen-specific SFU was detected in the INFγ ELISpot assay in all 12 participants. T cells from 8/12 participants loaded with both granzyme B and perforin in response to HIV antigen, an immune finding characteristic of long-term nonprogressors (LTNPs) and elite controllers (ECs). Thus administration of PENNVAX-B may prove useful adjunctive therapy to ART for treatment and control of HIV infection.

  2. Early stages of HIV replication: how to hijack cellular functions for a successful infection.

    Science.gov (United States)

    Lehmann-Che, Jacqueline; Saïb, Ali

    2004-01-01

    From the cell surface to the nucleus, the human immunodeficiency virus type 1 (HIV-1) will face multiple obstacles, crossing the plasma and nuclear membranes, but also finding its path within the cytoplasm in which elements from the cytoskeleton, organelles, and high a protein concentration, limit intracellular movements. At the same time, HIV-1 has to counteract cellular defenses--known as restriction factors--interfering with early steps of the virus cycle. Although the general outcomes of these early stages have been identified since several decades, the stepwise interactions taking place between cellular and viral components during this early journey, which will transform the incoming viral-RNA genome into a double-strand DNA competent for integration, remain largely unknown. In that sense, the uncoating process and the molecular basis of intracellular trafficking of preintegration complexes (PICs) are still poorly defined. Additionally, other key stages, which have been the focus of many reports, still require some clarifications, as is the case for the precise determinants of nuclear import of PICs. Finally, whereas the molecular mechanisms of integration, the last event of the early phase of retroviral life cycle, are now well understood, the choice of the integration site remains mysterious. Fully elucidating the early steps of HIV-1 replication is therefore crucial, not only for developing new antiretroviral drugs, but also for improving the design of lentiviral vectors for gene therapy. Since the mechanisms of HIV-1 entry and innate cell defenses were recently the topic of excellent reviews, we will focus here on uncoating and intracellular trafficking of HIV-1.

  3. The cellular protein hnRNP A2/B1 enhances HIV-1 transcription by unfolding LTR promoter G-quadruplexes

    Science.gov (United States)

    Scalabrin, Matteo; Frasson, Ilaria; Ruggiero, Emanuela; Perrone, Rosalba; Tosoni, Elena; Lago, Sara; Tassinari, Martina; Palù, Giorgio; Richter, Sara N.

    2017-01-01

    G-quadruplexes are four-stranded conformations of nucleic acids that act as cellular epigenetic regulators. A dynamic G-quadruplex forming region in the HIV-1 LTR promoter represses HIV-1 transcription when in the folded conformation. This activity is enhanced by nucleolin, which induces and stabilizes the HIV-1 LTR G-quadruplexes. In this work by a combined pull-down/mass spectrometry approach, we consistently found hnRNP A2/B1 as an additional LTR-G-quadruplex interacting protein. Surface plasmon resonance confirmed G-quadruplex specificity over linear sequences and fluorescence resonance energy transfer analysis indicated that hnRNP A2/B1 is able to efficiently unfold the LTR G-quadruplexes. Evaluation of the thermal stability of the LTR G-quadruplexes in different-length oligonucleotides showed that the protein is fit to be most active in the LTR full-length environment. When hnRNP A2/B1 was silenced in cells, LTR activity decreased, indicating that the protein acts as a HIV-1 transcription activator. Our data highlight a tightly regulated control of transcription based on G-quadruplex folding/unfolding, which depends on interacting cellular proteins. These findings provide a deeper understanding of the viral transcription mechanism and may pave the way to the development of drugs effective against the integrated HIV-1, present both in actively and latently infected cells.

  4. Cellular and humoral cross-immunity against two H3N2v influenza strains in presumably unexposed healthy and HIV-infected subjects.

    Directory of Open Access Journals (Sweden)

    Chiara Agrati

    Full Text Available Human cases of infection due to a novel swine-origin variant of influenza A virus subtype H3N2 (H3N2v have recently been identified in the United States. Pre-existing humoral and cellular immunity has been recognized as one of the key factors in limiting the infection burden of an emerging influenza virus strain, contributing to restrict its circulation and to mitigate clinical presentation. Aim of this study was to assess humoral and cell-mediated cross immune responses to H3N2v in immuno-competent (healthy donors, n = 45 and immuno-compromised hosts (HIV-infected subjects, n = 46 never exposed to H3N2v influenza strain. Humoral response against i H3N2v (A/H3N2/Ind/08/11, ii animal vaccine H3N2 strain (A/H3N2/Min/11/10, and iii pandemic H1N1 virus (A/H1N1/Cal/07/09 was analysed by hemagglutination inhibition assay; cell-mediated response against the same influenza strains was analysed by ELISpot assay. A large proportion of healthy and HIV subjects displayed cross-reacting humoral and cellular immune responses against two H3N2v strains, suggesting the presence of B- and T-cell clones able to recognize epitopes from emerging viral strains in both groups. Specifically, humoral response was lower in HIV subjects than in HD, and a specific age-related pattern of antibody response against different influenza strains was observed both in HD and in HIV. Cellular immune response was similar between HD and HIV groups and no relationship with age was reported. Finally, no correlation between humoral and cellular immune response was observed. Overall, a high prevalence of HD and HIV patients showing cross reactive immunity against two H3N2v strains was observed, with a slightly lower proportion in HIV persons. Other studies focused on HIV subjects at different stages of diseases are needed in order to define how cross immunity can be affected by advanced immunosuppression.

  5. Noncoding RNAs and HIV: viral manipulation of host dark matter to shape the cellular environment

    Directory of Open Access Journals (Sweden)

    Samantha eBarichievy

    2015-03-01

    Full Text Available On October 28th 1943 Winston Churchill said we shape our buildings, and afterwards our buildings shape us (Humes, 1994. Churchill was pondering how and when to rebuild the British House of Commons, which had been destroyed by enemy bombs on May 10th 1941. The old House had been small and insufficient to hold all its members, but was restored to its original form in 1950 in order to recapture the convenience and dignity that the building had shaped into its parliamentary members. The circular loop whereby buildings or dwellings are shaped and go on to shape those that reside in them is also true of pathogens and their hosts. As obligate parasites, pathogens need to alter their cellular host environments to ensure survival. Typically pathogens modify cellular transcription profiles and in doing so, the pathogen in turn is affected, thereby closing the loop. As key orchestrators of gene expression, noncoding RNAs provide a vast and extremely precise set of tools for pathogens to target in order to shape the cellular environment. This review will focus on host noncoding RNAs that are manipulated by the infamous intracellular pathogen, the Human Immunodeficiency Virus (HIV. We will briefly describe both short and long host noncoding RNAs and discuss how HIV gains control of these factors to ensure widespread dissemination throughout the host as well as the establishment of lifelong, chronic infection.

  6. Using Cellular Proteins to Reveal Mechanisms of HIV Infection | Center for Cancer Research

    Science.gov (United States)

    A vital step in HIV infection is the insertion of viral DNA into the genome of the host cell. In order for the insertion to occur, viral nucleic acid must be transported through the membrane that separates the main cellular compartment (the cytoplasm) from the nucleus, where the host DNA is located. Scientists are actively studying the mechanism used to transport viral DNA into the nucleus in the hopes of targeting this step with future anti-HIV treatments. Up to this point, researchers have identified some of the viral components that play a role in nuclear transport, but they have not determined how viral interactions with other molecules in the cell contribute to the process.

  7. Expression Analysis of Cellular Mir-29a and mir-29b in HIV Positive Patients

    Directory of Open Access Journals (Sweden)

    Hasan Kaleji (MSc

    2016-01-01

    Full Text Available Background and Objective: Various cellular factors affect the process of HIV activity. One of these cellular factors are structures known as microRN that are expected to be involved in controlling HIV replication and infectivity. The expression of one or a set of them may represent the patient's clinical conditions. In this study, the expression of miR-29a and miR-29b involved in regulating viral genes’ expression was evaluated in three HIV-positive groups and a healthy control group. Later, the expression level of these microRNAs was compared between the cases and controls. Methods: Total RNA extraction was performed on the collected samples using RNx-plus kit and then the microRNA expression levels were evaluated using Relative Real-time PCR. The obtained data was entered into SPSS 22 and Graphpad softwares and analyzed using Kruskal-Wallis and Man-Whitney tests. P-value of less than 0.05 was considered as statistical significance level. Results: The expression level of miR-29a was reduced in patients under treatment and drug-resistant patients ( P ≤ 0.05 . All three HIV-positive groups including people without drug treatment, patients under treatment and drug-resistant patients showed reduced miR-29b expression level compared to control group (P ≤ 0.05. Conclusion: the decreased expression of miR-29a and miR-29b in patients under treatment and drug-resistant patients indicates an increased viral replication and reduced CD4 cell count. It may be possible to predict the progression of the disease by miRNA measurement or control viral replication using these mir-RNAs that requires further studies.

  8. Modulation of cellular and humoral immune responses to anHIV-1 DNA vaccine by interleukin-12 and interleukin-18 DNA immunization

    Institute of Scientific and Technical Information of China (English)

    孙永涛; 王福祥; 孙永年; 徐哲; 王临旭; 刘娟; 白雪帆; 黄长形

    2004-01-01

    Objective: To investigate the effect of interleukin-12 (IL-12) and interleukin-18 (IL-18)DNA immunization on immune response induced by HIV-1 DNA vaccine and to explore new strategies for therapeutic HIV DNA vaccine.Methods: The recombinant expression vector pCI-neoGAG was constructed by inserting HIV Gag gene into the eukaryotic expression vector pCI-neo. Balb/c mice were immunized with pCI-neoGAG alone or co-immunized with the DNA encoding for IL-12 or IL-18. Anti-HIV antibody and IFN-γ were tested by ELISA, and splenocytes were isolated for detecting antigen-specific lymphoproliferative responses and specific CTL response by MTT assay and LDH assay respectively. Results: The antiHIV antibody titers of mice co-immunized with pCI-neoGAG and the DNA encoding for IL-12 or IL-18 were lower than that of mice immunized with pCI-neoGAG alone( P < 0.01). In contrast, the IFN-γ level of mice co-immunized with pCI-neoGAG and the DNA encoding for IL-12 or IL-18 was higher than that of mice immunized with pCI-neoGAG alone ( P <0.01). Furthermore, compared with mice injected with pCI-neoGAG alone, the specific CTL cytotoxity activity and antigenspecific lymphoproliferative responses of mice immunized with pCI-neoGAG and the DNA encoding for IL-12 or IL-18 were significantly enhanced respectively ( P < 0.01). Conclusion: The DNA encoding for IL-12 or IL-18 together with HIV DNA vaccine may enhance specific Th-1 responses and cellular immune response elicited in mice. Hence, the DNA encoding for IL-12 or IL-18 are promising immune adjuvants for HIV-1 DNA vaccine.

  9. Sequence and structure requirements for specific recognition of HIV-1 TAR and DIS RNA by the HIV-1 Vif protein.

    Science.gov (United States)

    Freisz, Séverine; Mezher, Joelle; Hafirassou, Lamine; Wolff, Philippe; Nominé, Yves; Romier, Christophe; Dumas, Philippe; Ennifar, Eric

    2012-07-01

    The HIV-1 Vif protein plays an essential role in the regulation of the infectivity of HIV-1 virion and in vivo pathogenesis. Vif neutralizes the human DNA-editing enzyme APOBEC3 protein, an antiretroviral cellular factor from the innate immune system, allowing the virus to escape the host defence system. It was shown that Vif is packaged into viral particles through specific interactions with the viral genomic RNA. Conserved and structured sequences from the 5'-noncoding region, such as the Tat-responsive element (TAR) or the genomic RNA dimerization initiation site (DIS), are primary binding sites for Vif. In the present study we used isothermal titration calorimetry to investigate sequence and structure determinants important for Vif binding to short viral RNA corresponding to TAR and DIS stem-loops. We showed that Vif specifically binds TAR and DIS in the low nanomolar range. In addition, Vif primarily binds the TAR UCU bulge, but not the apical loop. Determinants for Vif binding to the DIS loop-loop complex are likely more complex and involve the self-complementary loop together with the upper part of the stem. These results suggest that Tat-TAR inhibitors or DIS small molecule binders might be also effective to disturb Vif-TAR and Vif-DIS binding in order to reduce Vif packaging into virions.

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

    Directory of Open Access Journals (Sweden)

    Terrence M Dobrowsky

    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.

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

    Science.gov (United States)

    Dobrowsky, Terrence M; Daniels, Brian R; Siliciano, Robert F; Sun, Sean X; Wirtz, Denis

    2010-07-15

    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.

  12. Potent SIV-specific Cellular Immune Responses in the Breast Milk of SIV-infected, Lactating Rhesus Monkeys1

    OpenAIRE

    2008-01-01

    Breast milk transmission of HIV is a leading cause of infant HIV/AIDS in the developing world. Remarkably, only a small minority of breastfeeding infants born to HIV-infected mothers contract HIV via breast milk exposure, raising the possibility that immune factors in the breast milk confer protection to the infants who remain uninfected. To model HIV-specific immunity in breast milk, lactation was pharmacologically induced in Mamu-A*01+ female rhesus monkeys. The composition of lymphocyte su...

  13. Retrospective Proteomic Analysis of Cellular Immune Responses and Protective Correlates of p24 Vaccination in an HIV Elite Controller Using Antibody Arrays

    Directory of Open Access Journals (Sweden)

    Suneth S. Perera

    2016-06-01

    Full Text Available Background: HIV p24 is an extracellular HIV antigen involved in viral replication. Falling p24 antibody responses are associated with clinical disease progression and their preservation with non-progressive disease. Stimulation of p24 antibody production by immunization to delay progression was the basis of discontinued p24 vaccine. We studied a therapy-naive HIV+ man from Sydney, Australia, infected in 1988. He received the HIV-p24-virus like particle (VLP vaccine in 1993, and continues to show vigorous p24 antigen responses (>4% p24-specific CD4+ T cells, coupled with undetectable plasma viremia. We defined immune-protective correlates of p24 vaccination at the proteomic level through parallel retrospective analysis of cellular immune responses to p24 antigen in CD4+ and CD8+ T cells and CD14+ monocytes at viremic and aviremic phases using antibody-array. We found statistically significant coordinated up-regulation by all three cell-types with high fold-changes in fractalkine, ITAC, IGFBP-2, and MIP-1α in the aviremic phase. TECK and TRAIL-R4 were down-regulated in the viremic phase and up-regulated in the aviremic phase. The up-regulation of fractalkine in all three cell-types coincided with protective effect, whereas the dysfunction in anti-apoptotic chemokines with the loss of immune function. This study highlights the fact that induction of HIV-1-specific helper cells together with coordinated cellular immune response (p < 0.001 might be important in immunotherapeutic interventions and HIV vaccine development.

  14. Cellular immune correlates analysis of an HIV-1 preexposure prophylaxis trial

    Science.gov (United States)

    Kuebler, Peter J.; Mehrotra, Megha L.; McConnell, J. Jeff; Holditch, Sara J.; Shaw, Brian I.; Tarosso, Leandro F.; Leadabrand, Kaitlyn S.; Milush, Jeffrey M.; York, Vanessa A.; Raposo, Rui André Saraiva; Cheng, Rex G.; Eriksson, Emily M.; McMahan, Vanessa; Glidden, David V.; Shiboski, Stephen; Grant, Robert M.; Nixon, Douglas F.; Kallás, Esper G.

    2015-01-01

    HIV-1–specific T-cell responses in exposed seronegative subjects suggest that a viral breach of the exposure site is more common than current transmission rates would suggest and that host immunity can extinguish subsequent infection foci. The Preexposure Prophylaxis Initiative (iPrEx) chemoprophylaxis trial provided an opportunity to rigorously investigate these responses in a case–control immunology study; 84 preinfection peripheral blood mononuclear cell samples from individuals enrolled in the iPrEx trial who later seroconverted were matched with 480 samples from enrolled subjects who remained seronegative from both the placebo and active treatment arms. T-cell responses to HIV-1 Gag, Protease, Integrase, Reverse Transcriptase, Vif, and Nef antigens were quantified for all subjects in an IFN-γ enzyme-linked immunospot (ELISpot) assay. IFN-γ responses varied in magnitude and frequency across subjects. A positive response was more prevalent in those who remained persistently HIV-1–negative for Gag (P = 0.007), Integrase (P < 0.001), Vif (P < 0.001), and Nef (P < 0.001). When correlated with outcomes in the iPrEx trial, Vif- and Integrase-specific T-cell responses were associated with reduced HIV-1 infection risk [hazard ratio (HR) = 0.36, 95% confidence interval (95% CI) = 0.19–0.66 and HR = 0.52, 95% CI = 0.28–0.96, respectively]. Antigen-specific responses were independent of emtricitabine/tenofovir disoproxil fumarate use. IFN-γ secretion in the ELISpot was confirmed using multiparametric flow cytometry and largely attributed to effector memory CD4+ or CD8+ T cells. Our results show that HIV-1–specific T-cell immunity can be detected in exposed but uninfected individuals and that these T-cell responses can differentiate individuals according to infection outcomes. PMID:26100867

  15. Quantification of the epitope diversity of HIV-1-specific binding antibodies by peptide microarrays for global HIV-1 vaccine development.

    Science.gov (United States)

    Stephenson, Kathryn E; Neubauer, George H; Reimer, Ulf; Pawlowski, Nikolaus; Knaute, Tobias; Zerweck, Johannes; Korber, Bette T; Barouch, Dan H

    2015-01-01

    An effective vaccine against human immunodeficiency virus type 1 (HIV-1) will have to provide protection against a vast array of different HIV-1 strains. Current methods to measure HIV-1-specific binding antibodies following immunization typically focus on determining the magnitude of antibody responses, but the epitope diversity of antibody responses has remained largely unexplored. Here we describe the development of a global HIV-1 peptide microarray that contains 6564 peptides from across the HIV-1 proteome and covers the majority of HIV-1 sequences in the Los Alamos National Laboratory global HIV-1 sequence database. Using this microarray, we quantified the magnitude, breadth, and depth of IgG binding to linear HIV-1 sequences in HIV-1-infected humans and HIV-1-vaccinated humans, rhesus monkeys and guinea pigs. The microarray measured potentially important differences in antibody epitope diversity, particularly regarding the depth of epitope variants recognized at each binding site. Our data suggest that the global HIV-1 peptide microarray may be a useful tool for both preclinical and clinical HIV-1 research. Copyright © 2014. Published by Elsevier B.V.

  16. Mathematical model for HIV dynamics in HIV-specific helper cells

    Science.gov (United States)

    Pinto, Carla M. A.; Carvalho, Ana

    2014-03-01

    In this paper we study a delay mathematical model for the dynamics of HIV in HIV-specific CD4 + T helper cells. We modify the model presented by Roy and Wodarz in 2012, where the HIV dynamics is studied, considering a single CD4 + T cell population. Non-specific helper cells are included as alternative target cell population, to account for macrophages and dendritic cells. In this paper, we include two types of delay: (1) a latent period between the time target cells are contacted by the virus particles and the time the virions enter the cells and; (2) virus production period for new virions to be produced within and released from the infected cells. We compute the reproduction number of the model, R0, and the local stability of the disease free equilibrium and of the endemic equilibrium. We find that for values of R01, the model approximates asymptotically the endemic equilibrium. We observe numerically the phenomenon of backward bifurcation for values of R0⪅1. This statement will be proved in future work. We also vary the values of the latent period and the production period of infected cells and free virus. We conclude that increasing these values translates in a decrease of the reproduction number. Thus, a good strategy to control the HIV virus should focus on drugs to prolong the latent period and/or slow down the virus production. These results suggest that the model is mathematically and epidemiologically well-posed.

  17. Cellular Immune Responses and Viral Diversity in Individuals Treated during Acute and Early HIV-1 Infection

    Science.gov (United States)

    Altfeld, Marcus; Rosenberg, Eric S.; Shankarappa, Raj; Mukherjee, Joia S.; Hecht, Frederick M.; Eldridge, Robert L.; Addo, Marylyn M.; Poon, Samuel H.; Phillips, Mary N.; Robbins, Gregory K.; Sax, Paul E.; Boswell, Steve; Kahn, James O.; Brander, Christian; Goulder, Philip J.R.; Levy, Jay A.; Mullins, James I.; Walker, Bruce D.

    2001-01-01

    Immune responses induced during the early stages of chronic viral infections are thought to influence disease outcome. Using HIV as a model, we examined virus-specific cytotoxic T lymphocytes (CTLs), T helper cells, and viral genetic diversity in relation to duration of infection and subsequent response to antiviral therapy. Individuals with acute HIV-1 infection treated before seroconversion had weaker CTL responses directed at fewer epitopes than persons who were treated after seroconversion. However, treatment-induced control of viremia was associated with the development of strong T helper cell responses in both groups. After 1 yr of antiviral treatment initiated in acute or early infection, all epitope-specific CTL responses persisted despite undetectable viral loads. The breadth and magnitude of CTL responses remained significantly less in treated acute infection than in treated chronic infection, but viral diversity was also significantly less with immediate therapy. We conclude that early treatment of acute HIV infection leads to a more narrowly directed CTL response, stronger T helper cell responses, and a less diverse virus population. Given the need for T helper cells to maintain effective CTL responses and the ability of virus diversification to accommodate immune escape, we hypothesize that early therapy of primary infection may be beneficial despite induction of less robust CTL responses. These data also provide rationale for therapeutic immunization aimed at broadening CTL responses in treated primary HIV infection. PMID:11148221

  18. Abundance of early functional HIV-specific CD8+ T cells does not predict AIDS-free survival time.

    Directory of Open Access Journals (Sweden)

    Ingrid M M Schellens

    Full Text Available BACKGROUND: T-cell immunity is thought to play an important role in controlling HIV infection, and is a main target for HIV vaccine development. HIV-specific central memory CD8(+ and CD4(+ T cells producing IFNgamma and IL-2 have been associated with control of viremia and are therefore hypothesized to be truly protective and determine subsequent clinical outcome. However, the cause-effect relationship between HIV-specific cellular immunity and disease progression is unknown. We investigated in a large prospective cohort study involving 96 individuals of the Amsterdam Cohort Studies with a known date of seroconversion whether the presence of cytokine-producing HIV-specific CD8(+ T cells early in infection was associated with AIDS-free survival time. METHODS AND FINDINGS: The number and percentage of IFNgamma and IL-2 producing CD8(+ T cells was measured after in vitro stimulation with an overlapping Gag-peptide pool in T cells sampled approximately one year after seroconversion. Kaplan-Meier survival analysis and Cox proportional hazard models showed that frequencies of cytokine-producing Gag-specific CD8(+ T cells (IFNgamma, IL-2 or both shortly after seroconversion were neither associated with time to AIDS nor with the rate of CD4(+ T-cell decline. CONCLUSIONS: These data show that high numbers of functional HIV-specific CD8(+ T cells can be found early in HIV infection, irrespective of subsequent clinical outcome. The fact that both progressors and long-term non-progressors have abundant T cell immunity of the specificity associated with low viral load shortly after seroconversion suggests that the more rapid loss of T cell immunity observed in progressors may be a consequence rather than a cause of disease progression.

  19. DNA Prime-Boost Vaccine Regimen To Increase Breadth, Magnitude, and Cytotoxicity of the Cellular Immune Responses to Subdominant Gag Epitopes of Simian Immunodeficiency Virus and HIV.

    Science.gov (United States)

    Hu, Xintao; Valentin, Antonio; Dayton, Frances; Kulkarni, Viraj; Alicea, Candido; Rosati, Margherita; Chowdhury, Bhabadeb; Gautam, Rajeev; Broderick, Kate E; Sardesai, Niranjan Y; Martin, Malcolm A; Mullins, James I; Pavlakis, George N; Felber, Barbara K

    2016-11-15

    HIV sequence diversity and the propensity of eliciting immunodominant responses targeting variable regions of the HIV proteome are hurdles in the development of an effective AIDS vaccine. An HIV-derived conserved element (CE) p24(gag) plasmid DNA (pDNA) vaccine is able to redirect immunodominant responses to otherwise subdominant and often more vulnerable viral targets. By homology to the HIV immunogen, seven CE were identified in SIV p27(Gag) Analysis of 31 rhesus macaques vaccinated with full-length SIV gag pDNA showed inefficient induction (58% response rate) of cellular responses targeting these CE. In contrast, all 14 macaques immunized with SIV p27CE pDNA developed robust T cell responses recognizing CE. Vaccination with p27CE pDNA was also critical for the efficient induction and increased the frequency of Ag-specific T cells with cytotoxic potential (granzyme B(+) CD107a(+)) targeting subdominant CE epitopes, compared with the responses elicited by the p57(gag) pDNA vaccine. Following p27CE pDNA priming, two booster regimens, gag pDNA or codelivery of p27CE+gag pDNA, significantly increased the levels of CE-specific T cells. However, the CE+gag pDNA booster vaccination elicited significantly broader CE epitope recognition, and thus, a more profound alteration of the immunodominance hierarchy. Vaccination with HIV molecules showed that CE+gag pDNA booster regimen further expanded the breadth of HIV CE responses. Hence, SIV/HIV vaccine regimens comprising CE pDNA prime and CE+gag pDNA booster vaccination significantly increased cytotoxic T cell responses to subdominant highly conserved Gag epitopes and maximized response breadth. Copyright © 2016 by The American Association of Immunologists, Inc.

  20. Translational regulation of HIV-1 replication by HIV-1 Rev cellular cofactors Sam68, eIF5A, hRIP, and DDX3.

    Science.gov (United States)

    Liu, Jinfeng; Henao-Mejia, Jorge; Liu, Hao; Zhao, Yingren; He, Johnny J

    2011-06-01

    Nuclear export and translation of HIV-1 RNA are two important posttranscriptional events for HIV-1 gene expression and replication. HIV-1 Rev functions to export unspliced and incompletely spliced HIV-1 RNA from the nucleus to the cytoplasm; it requires interaction with several cellular cofactors such as Sam68, eIF5A, hRIP, and DDX3. Meanwhile, some studies have also implicated Rev and some of its cofactors such as Sam68 in HIV-1 RNA translation. Thus, in this study, we aimed to characterize the potential function of all these four Rev cofactors in HIV-1 RNA translation. Ectopic expression, siRNA knockdown, and trans-complementation assays confirmed that all these cofactors were very important for HIV-1 gene expression and production through Rev and, accordingly, Rev-dependent reporter gene expression. Importantly, these studies revealed for the first time that each of these cofactors also regulated Rev-independent reporter gene expression. To directly determine the roles of these cofactors in HIV-1 RNA translation, we designed and synthesized a full-length capped HIV-1 RNA in vitro, transfected it into cells to bypass the RNA nuclear export step, and determined HIV-1 Gag expression from the cytoplasmic RNA in the cells that had ectopically expressed or siRNA knocked down cofactors. Gag expression was found to closely correlate with the expression levels of all these cofactors. Furthermore, we took advantage of a HIV-1 internal ribosomal entry site (IRES)-based bicistronic reporter gene assay and determined the effects of these cofactors on cap-independent IRES-mediated HIV-1 translation. The results showed that DDX3, eIF5A, and hRIP enhanced HIV-1 IRES-mediated translation, whereas Sam68 did not. Taken together, these results show that HIV-1 Rev cofactors Sam68, eIF5A, hRIP, and DDX3 also function in the translation of HIV-1 RNA and suggest that the regulatory mechanisms of HIV-1 RNA translation are likely different among these cofactors.

  1. Effect of Schistosoma mansoni Infection on Innate and HIV-1-Specific T-Cell Immune Responses in HIV-1-Infected Ugandan Fisher Folk.

    Science.gov (United States)

    Obuku, Andrew Ekii; Asiki, Gershim; Abaasa, Andrew; Ssonko, Isaac; Harari, Alexandre; van Dam, Govert J; Corstjens, Paul L; Joloba, Moses; Ding, Song; Mpendo, Juliet; Nielsen, Leslie; Kamali, Anatoli; Elliott, Alison M; Pantaleo, Giuseppe; Kaleebu, Pontiano; Pala, Pietro

    2016-07-01

    In Uganda, fisher folk have HIV prevalence rates, about four times higher than the national average, and are often coinfected with Schistosoma mansoni. We hypothesized that innate immune responses and HIV-specific Th1 immune responses might be downmodulated in HIV/S. mansoni-coinfected individuals compared with HIV+/S. mansoni-negative individuals. We stimulated whole blood with innate receptor agonists and analyzed supernatant cytokines by Luminex. We evaluated HIV-specific responses by intracellular cytokine staining for IFN-γ, IL-2, and TNF-α. We found that the plasma viral load and CD4 count were similar between the HIV+SM+ and HIV+SM- individuals. In addition, the TNF-α response to the imidazoquinoline compound CL097 and β-1, 3-glucan (curdlan), was significantly higher in HIV/S. mansoni-coinfected individuals compared with HIV only-infected individuals. The frequency of HIV-specific IFN-γ+IL-2-TNF-α- CD8 T cells and IFN-γ+IL-2-TNF-α+ CD4 T cells was significantly higher in HIV/S. mansoni-coinfected individuals compared with HIV only-infected individuals. These findings do not support the hypothesis that S. mansoni downmodulates innate or HIV-specific Th1 responses in HIV/S. mansoni-coinfected individuals.

  2. Structural definition of an antibody-dependent cellular cytotoxicity response implicated in reduced risk for HIV-1 infection.

    Science.gov (United States)

    Acharya, Priyamvada; Tolbert, William D; Gohain, Neelakshi; Wu, Xueji; Yu, Lei; Liu, Tongyun; Huang, Wensheng; Huang, Chih-Chin; Kwon, Young Do; Louder, Robert K; Luongo, Timothy S; McLellan, Jason S; Pancera, Marie; Yang, Yongping; Zhang, Baoshan; Flinko, Robin; Foulke, James S; Sajadi, Mohammad M; Kamin-Lewis, Roberta; Robinson, James E; Martin, Loïc; Kwong, Peter D; Guan, Yongjun; DeVico, Anthony L; Lewis, George K; Pazgier, Marzena

    2014-11-01

    The RV144 vaccine trial implicated epitopes in the C1 region of gp120 (A32-like epitopes) as targets of potentially protective antibody-dependent cellular cytotoxicity (ADCC) responses. A32-like epitopes are highly immunogenic, as infected or vaccinated individuals frequently produce antibodies specific for these determinants. Antibody titers, as measured by enzyme-linked immunosorbent assay (ELISA) against these epitopes, however, do not consistently correlate with protection. Here, we report crystal structures of CD4-stabilized gp120 cores complexed with the Fab fragments of two nonneutralizing, A32-like monoclonal antibodies (MAbs), N5-i5 and 2.2c, that compete for antigen binding and have similar antigen-binding affinities yet exhibit a 75-fold difference in ADCC potency. We find that these MAbs recognize overlapping epitopes formed by mobile layers 1 and 2 of the gp120 inner domain, including the C1 and C2 regions, but bind gp120 at different angles via juxtaposed VH and VL contact surfaces. A comparison of structural and immunological data further showed that antibody orientation on bound antigen and the capacity to form multivalent antigen-antibody complexes on target cells were key determinants of ADCC potency, with the latter process having the greater impact. These studies provide atomic-level definition of A32-like epitopes implicated as targets of protective antibodies in RV144. Moreover, these studies establish that epitope structure and mode of antibody binding can dramatically affect the potency of Fc-mediated effector function against HIV-1. These results provide key insights for understanding, refining, and improving the outcome of HIV vaccine trials, in which relevant immune responses are facilitated by A32-like elicited responses. HIV-1 Env is a primary target for antibodies elicited during infection. Although a small number of infected individuals elicit broadly neutralizing antibodies, the bulk of the humoral response consists of antibodies

  3. Toll-Like Receptor 7 Agonist GS-9620 Induces HIV Expression and HIV-Specific Immunity in Cells from HIV-Infected Individuals on Suppressive Antiretroviral Therapy.

    Science.gov (United States)

    Tsai, Angela; Irrinki, Alivelu; Kaur, Jasmine; Cihlar, Tomas; Kukolj, George; Sloan, Derek D; Murry, Jeffrey P

    2017-04-15

    Antiretroviral therapy can suppress HIV replication to undetectable levels but does not eliminate latent HIV, thus necessitating lifelong therapy. Recent efforts to target this persistent reservoir have focused on inducing the expression of latent HIV so that infected cells may be recognized and eliminated by the immune system. Toll-like receptor (TLR) activation stimulates antiviral immunity and has been shown to induce HIV from latently infected cells. Activation of TLR7 leads to the production of several stimulatory cytokines, including type I interferons (IFNs). In this study, we show that the selective TLR7 agonist GS-9620 induced HIV in peripheral blood mononuclear cells (PBMCs) from HIV-infected individuals on suppressive antiretroviral therapy. GS-9620 increased extracellular HIV RNA 1.5- to 2-fold through a mechanism that required type I IFN signaling. GS-9620 also activated HIV-specific T cells and enhanced antibody-mediated clearance of HIV-infected cells. Activation by GS-9620 in combination with HIV peptide stimulation increased CD8 T cell degranulation, production of intracellular cytokines, and cytolytic activity. T cell activation was again dependent on type I IFNs produced by plasmacytoid dendritic cells. GS-9620 induced phagocytic cell maturation and improved effector-mediated killing of HIV-infected CD4 T cells by the HIV envelope-specific broadly neutralizing antibody PGT121. Collectively, these data show that GS-9620 can activate HIV production and improve the effector functions that target latently infected cells. GS-9620 may effectively complement orthogonal therapies designed to stimulate antiviral immunity, such as therapeutic vaccines or broadly neutralizing antibodies. Clinical studies are under way to determine if GS-9620 can target HIV reservoirs.IMPORTANCE Though antiretroviral therapies effectively suppress viral replication, they do not eliminate integrated proviral DNA. This stable intermediate of viral infection is persistently

  4. Toll-Like Receptor 7 Agonist GS-9620 Induces HIV Expression and HIV-Specific Immunity in Cells from HIV-Infected Individuals on Suppressive Antiretroviral Therapy

    Science.gov (United States)

    Tsai, Angela; Irrinki, Alivelu; Kaur, Jasmine; Cihlar, Tomas; Kukolj, George

    2017-01-01

    ABSTRACT Antiretroviral therapy can suppress HIV replication to undetectable levels but does not eliminate latent HIV, thus necessitating lifelong therapy. Recent efforts to target this persistent reservoir have focused on inducing the expression of latent HIV so that infected cells may be recognized and eliminated by the immune system. Toll-like receptor (TLR) activation stimulates antiviral immunity and has been shown to induce HIV from latently infected cells. Activation of TLR7 leads to the production of several stimulatory cytokines, including type I interferons (IFNs). In this study, we show that the selective TLR7 agonist GS-9620 induced HIV in peripheral blood mononuclear cells (PBMCs) from HIV-infected individuals on suppressive antiretroviral therapy. GS-9620 increased extracellular HIV RNA 1.5- to 2-fold through a mechanism that required type I IFN signaling. GS-9620 also activated HIV-specific T cells and enhanced antibody-mediated clearance of HIV-infected cells. Activation by GS-9620 in combination with HIV peptide stimulation increased CD8 T cell degranulation, production of intracellular cytokines, and cytolytic activity. T cell activation was again dependent on type I IFNs produced by plasmacytoid dendritic cells. GS-9620 induced phagocytic cell maturation and improved effector-mediated killing of HIV-infected CD4 T cells by the HIV envelope-specific broadly neutralizing antibody PGT121. Collectively, these data show that GS-9620 can activate HIV production and improve the effector functions that target latently infected cells. GS-9620 may effectively complement orthogonal therapies designed to stimulate antiviral immunity, such as therapeutic vaccines or broadly neutralizing antibodies. Clinical studies are under way to determine if GS-9620 can target HIV reservoirs. IMPORTANCE Though antiretroviral therapies effectively suppress viral replication, they do not eliminate integrated proviral DNA. This stable intermediate of viral infection is

  5. Specific cytotoxic T lymphocyte responses in Chinese HIV/AIDS patients

    Institute of Scientific and Technical Information of China (English)

    尚红; 韩晓旭; 王亚男; 周立平; 张子宁; 姜拥军; 张旻; 于旭

    2004-01-01

    Human immunodeficiency virus type 1 (HIV-1)-specific cytotoxic T lymphocytes (CTL) are considered to play a central role in the immune response against HIV-1. During untreated acute HIV-1 infection, virus-specific CTL activity is associated with the initial decrease in viremia.1 After HIV infection, those individuals with a slow progressive course develop stronger CTL responses than those with typical disease progression.2,3 Restoring HIV-1-specific CTL responses have been considered a key factor in immune reconstitution and vaccine development. Here we present the analysis of HIV-1 Gag-specific CTL responses in 23 Chinese HIV/AIDS cases in order to take the initial steps at identifying the epitopes that dominate the CTL response in Chinese patients.

  6. Use of HIV-1 specific immunoglobulin G3 as a serological marker of vertical transmission.

    Science.gov (United States)

    Madurai, S; Moodley, D; Coovadia, H M; Bobat, R A; Gopaul, W; Smith, A N; York, D F

    1996-12-01

    The objective of the study was to indicate HIV infection in infants. The patients were part of a longitudinal cohort of 43 infants born to HIV seropositive mothers. A modified Genelavia EIA primarily directed against HIV envelope proteins was used. An alkaline phosphatase labelled IgG3 conjugate was substituted in place of the kit conjugate. HIV specific IgG3 clearance was optimal at 6 months, whilst HIV total antibody was reliable only from age 12 months onwards. At 6 months no detectable IgG3 were found in 91 per cent of uninfected infants where more of these infants had reduced their total HIV antibody titres at the same period. We confirm that HIV specific IgG3 measurement is a reliable and cost effective means of identifying HIV infected infants from 6 months of age onwards.

  7. Evaluation of Cellular Phenotypes Implicated in Immunopathogenesis and Monitoring Immune Reconstitution Inflammatory Syndrome in HIV/Leprosy Cases

    Science.gov (United States)

    Giacoia-Gripp, Carmem Beatriz Wagner; Sales, Anna Maria; Nery, José Augusto da Costa; Santos-Oliveira, Joanna Reis; de Oliveira, Ariane Leite; Sarno, Euzenir Nunes; Morgado, Mariza Gonçalves

    2011-01-01

    Background It is now evident that HAART-associated immunological improvement often leads to a variety of new clinical manifestations, collectively termed immune reconstitution inflammatory syndrome, or IRIS. This phenomenon has already been described in cases of HIV coinfection with Mycobacterium leprae, most of them belonging to the tuberculoid spectrum of leprosy disease, as observed in leprosy reversal reaction (RR). However, the events related to the pathogenesis of this association need to be clarified. This study investigated the immunological profile of HIV/leprosy patients, with special attention to the cellular activation status, to better understand the mechanisms related to IRIS/RR immunopathogenesis, identifying any potential biomarkers for IRIS/RR intercurrence. Methods/Principal Findings Eighty-five individuals were assessed in this study: HIV/leprosy and HIV-monoinfected patients, grouped according to HIV-viral load levels, leprosy patients without HIV coinfection, and healthy controls. Phenotypes were evaluated by flow cytometry for T cell subsets and immune differentiation/activation markers. As expected, absolute counts of the CD4+ and CD8+ T cells from the HIV-infected individuals changed in relation to those of the leprosy patients and controls. However, there were no significant differences among the groups, whether in the expression of cellular differentiation phenotypes or cellular activation, as reflected by the expression of CD38 and HLA-DR. Six HIV/leprosy patients identified as IRIS/RR were analyzed during IRIS/RR episodes and after prednisone treatment. These patients presented high cellular activation levels regarding the expression of CD38 in CD8+ cells T during IRIS/RR (median: 77,15%), dropping significantly (p<0,05) during post-IRIS/RR moments (median: 29,7%). Furthermore, an increase of cellular activation seems to occur prior to IRIS/RR. Conclusion/Significance These data suggest CD38 expression in CD8+ T cells interesting tool

  8. Evaluation of cellular phenotypes implicated in immunopathogenesis and monitoring immune reconstitution inflammatory syndrome in HIV/leprosy cases.

    Directory of Open Access Journals (Sweden)

    Carmem Beatriz Wagner Giacoia-Gripp

    Full Text Available BACKGROUND: It is now evident that HAART-associated immunological improvement often leads to a variety of new clinical manifestations, collectively termed immune reconstitution inflammatory syndrome, or IRIS. This phenomenon has already been described in cases of HIV coinfection with Mycobacterium leprae, most of them belonging to the tuberculoid spectrum of leprosy disease, as observed in leprosy reversal reaction (RR. However, the events related to the pathogenesis of this association need to be clarified. This study investigated the immunological profile of HIV/leprosy patients, with special attention to the cellular activation status, to better understand the mechanisms related to IRIS/RR immunopathogenesis, identifying any potential biomarkers for IRIS/RR intercurrence. METHODS/PRINCIPAL FINDINGS: Eighty-five individuals were assessed in this study: HIV/leprosy and HIV-monoinfected patients, grouped according to HIV-viral load levels, leprosy patients without HIV coinfection, and healthy controls. Phenotypes were evaluated by flow cytometry for T cell subsets and immune differentiation/activation markers. As expected, absolute counts of the CD4+ and CD8+ T cells from the HIV-infected individuals changed in relation to those of the leprosy patients and controls. However, there were no significant differences among the groups, whether in the expression of cellular differentiation phenotypes or cellular activation, as reflected by the expression of CD38 and HLA-DR. Six HIV/leprosy patients identified as IRIS/RR were analyzed during IRIS/RR episodes and after prednisone treatment. These patients presented high cellular activation levels regarding the expression of CD38 in CD8+ cells T during IRIS/RR (median: 77,15%, dropping significantly (p<0,05 during post-IRIS/RR moments (median: 29,7%. Furthermore, an increase of cellular activation seems to occur prior to IRIS/RR. CONCLUSION/SIGNIFICANCE: These data suggest CD38 expression in CD8+ T cells

  9. HIV-1 DNA vaccine with adjuvant cytokines induces specific immune responses against HIV-1 infection in mice

    Institute of Scientific and Technical Information of China (English)

    WANG Fu-xiang; SUN Yong-tao; WANG Lin-xu; LIU Juan

    2006-01-01

    @@ There is mounting evidence that the induction of strong mucosal and cell-mediated immune responses is key element to consider in constructing efficacious HIV-1 vaccine. Therapeutic vaccines that induce high levels of CTL specific to HIV are currently being developed worldwide.

  10. CD4+ T cell-mediated presentation of non-infectious HIV-1virion antigens to HIV-specific CD8+ T cells

    Institute of Scientific and Technical Information of China (English)

    XU Jian-qing; Franco Lori; Julianna Lisziewicz

    2006-01-01

    Background The mechanism of chronic immune activation and impairment of HIV-specific immune responses during chronic infection is not fully understood. However, it is known that high immune activation leads to more rapid progression to AIDS. We hypothesize that CD4+ T cell-mediated viral antigen presentation contributes to this pathologic immune activation in HIV-infected individuals.Methods HIV-specific T cells, responding to noninfectious HIV-1 virions as antigen, were measured by flow cytometric assays. These experimental conditions reflect the in vivo condition where noninfectious HIV-1 represents more than 99% of the antigens.Results CD4+ T cells purified from HIV-infected individuals were capable of cross presenting exogenous noninfectious HIV-1 virions to HIV-1-specific CD8+ T cells. Cross presentation required the entry of HIV-1 to CD4+ T cells and antigen translocation from endoplasmic reticulum to the Golgi complex. Blocking CD4+mediated activation of HIV-specific CD8+ T cells and redirecting the viral antigens to antigen presenting cells improved HIV-specific T cell responses.Conclusions One possible cause of chronic immune activation and impairment of HIV-1 specific T cell responses is represented by HIV-1 harboring CD4+ T cells cross presenting HIV-1 antigen to activate CD8+ T cells. This new mechanism provides the first evidence that cross presentation of noninfectious HIV-1. Virions play a role in the immunopathogenesis of HIV-1 infection.

  11. HIV-1 capture and transmission by dendritic cells: the role of viral glycolipids and the cellular receptor Siglec-1.

    Directory of Open Access Journals (Sweden)

    Nuria Izquierdo-Useros

    2014-07-01

    Full Text Available Dendritic cells (DCs are essential in order to combat invading viruses and trigger antiviral responses. Paradoxically, in the case of HIV-1, DCs might contribute to viral pathogenesis through trans-infection, a mechanism that promotes viral capture and transmission to target cells, especially after DC maturation. In this review, we highlight recent evidence identifying sialyllactose-containing gangliosides in the viral membrane and the cellular lectin Siglec-1 as critical determinants for HIV-1 capture and storage by mature DCs and for DC-mediated trans-infection of T cells. In contrast, DC-SIGN, long considered to be the main receptor for DC capture of HIV-1, plays a minor role in mature DC-mediated HIV-1 capture and trans-infection.

  12. Bioprinting Cellularized Constructs Using a Tissue-specific Hydrogel Bioink.

    Science.gov (United States)

    Skardal, Aleksander; Devarasetty, Mahesh; Kang, Hyun-Wook; Seol, Young-Joon; Forsythe, Steven D; Bishop, Colin; Shupe, Thomas; Soker, Shay; Atala, Anthony

    2016-04-21

    Bioprinting has emerged as a versatile biofabrication approach for creating tissue engineered organ constructs. These constructs have potential use as organ replacements for implantation in patients, and also, when created on a smaller size scale as model "organoids" that can be used in in vitro systems for drug and toxicology screening. Despite development of a wide variety of bioprinting devices, application of bioprinting technology can be limited by the availability of materials that both expedite bioprinting procedures and support cell viability and function by providing tissue-specific cues. Here we describe a versatile hyaluronic acid (HA) and gelatin-based hydrogel system comprised of a multi-crosslinker, 2-stage crosslinking protocol, which can provide tissue specific biochemical signals and mimic the mechanical properties of in vivo tissues. Biochemical factors are provided by incorporating tissue-derived extracellular matrix materials, which include potent growth factors. Tissue mechanical properties are controlled combinations of PEG-based crosslinkers with varying molecular weights, geometries (linear or multi-arm), and functional groups to yield extrudable bioinks and final construct shear stiffness values over a wide range (100 Pa to 20 kPa). Using these parameters, hydrogel bioinks were used to bioprint primary liver spheroids in a liver-specific bioink to create in vitro liver constructs with high cell viability and measurable functional albumin and urea output. This methodology provides a general framework that can be adapted for future customization of hydrogels for biofabrication of a wide range of tissue construct types.

  13. Human immunodeficiency virus type 1 Tat increases the expression of cleavage and polyadenylation specificity factor 73-kilodalton subunit modulating cellular and viral expression.

    Science.gov (United States)

    Calzado, Marco A; Sancho, Rocío; Muñoz, Eduardo

    2004-07-01

    The human immunodeficiency virus type 1 (HIV-1) Tat protein, which is essential for HIV gene expression and viral replication, is known to mediate pleiotropic effects on various cell functions. For instance, Tat protein is able to regulate the rate of transcription of host cellular genes and to interact with the signaling machinery, leading to cellular dysfunction. To study the effect that HIV-1 Tat exerts on the host cell, we identified several genes that were up- or down-regulated in tat-expressing cell lines by using the differential display method. HIV-1 Tat specifically increases the expression of the cleavage and polyadenylation specificity factor (CPSF) 73-kDa subunit (CPSF3) without affecting the expression of the 160- and 100-kDa subunits of the CPSF complex. This complex comprises four subunits and has a key function in the 3'-end processing of pre-mRNAs by a coordinated interaction with other factors. CPSF3 overexpression experiments and knockdown of the endogenous CPSF3 by mRNA interference have shown that this subunit of the complex is an important regulatory protein for both viral and cellular gene expression. In addition to the known CPSF3 function in RNA polyadenylation, we also present evidence that this protein exerts transcriptional activities by repressing the mdm2 gene promoter. Thus, HIV-1-Tat up-regulation of CPSF3 could represent a novel mechanism by which this virus increases mRNA processing, causing an increase in both cell and viral gene expression.

  14. Stimulation of HIV-specific T cell clonotypes using allogeneic HLA.

    Science.gov (United States)

    Almeida, Coral-Ann; van Miert, Paula; O'Driscoll, Kane; Zoet, Yvonne M; Chopra, Abha; Watson, Mark; de Santis, Dianne; Witt, Campbell; John, Mina; Claas, Frans H J; D'Orsogna, Lloyd J

    2017-03-28

    We hypothesized that HIV-specific CD8 T cell clonotypes can be stimulated by allogeneic HLA molecules. Multiple HIV-specific CD8 T cell clones were derived from 12 individuals with chronic HIV infection, specific for 13 different HIV Gag antigens and restricted to 7 different HLA molecules. The generated T cell clones were assayed for alloreactivity against a panel of single HLA class I expressing cell lines (SALs). HIV-specific T cells recognising at least one allogeneic HLA molecule could be identified from 7 of 12 patients tested. Allorecognition was associated with IFNγ cytokine production, CD137 upregulation and cytotoxicity, suggesting high avidity allo-stimulation. Allo-HLA recognition by HIV-specific T cells was specific to the HIV target peptide/HLA restriction and TCR TRBV usage of the T cells. HIV-specific T cells do crossreact against allogeneic HLA molecules in an epitope and TRBV specific manner. Therefore allo-HLA stimulation could be exploited to induce or augment HIV-specific T cell responses.

  15. Deletion of Specific Immune-Modulatory Genes from Modified Vaccinia Virus Ankara-Based HIV Vaccines Engenders Improved Immunogenicity in Rhesus Macaques

    Science.gov (United States)

    O'Mara, Leigh A.; Gangadhara, Sailaja; McQuoid, Monica; Zhang, Xiugen; Zheng, Rui; Gill, Kiran; Verma, Meena; Yu, Tianwei; Johnson, Brent; Li, Bing; Derdeyn, Cynthia A.; Ibegbu, Chris; Altman, John D.; Hunter, Eric; Feinberg, Mark B.

    2012-01-01

    Modified vaccinia virus Ankara (MVA) is a safe, attenuated orthopoxvirus that is being developed as a vaccine vector but has demonstrated limited immunogenicity in several early-phase clinical trials. Our objective was to rationally improve the immunogenicity of MVA-based HIV/AIDS vaccines via the targeted deletion of specific poxvirus immune-modulatory genes. Vaccines expressing codon-optimized HIV subtype C consensus Env and Gag antigens were generated from MVA vector backbones that (i) harbor simultaneous deletions of four viral immune-modulatory genes, encoding an interleukin-18 (IL-18) binding protein, an IL-1β receptor, a dominant negative Toll/IL-1 signaling adapter, and CC-chemokine binding protein (MVAΔ4-HIV); (ii) harbor a deletion of an additional (fifth) viral gene, encoding uracil-DNA glycosylase (MVAΔ5-HIV); or (iii) represent the parental MVA backbone as a control (MVA-HIV). We performed head-to-head comparisons of the cellular and humoral immune responses that were elicited by these vectors during homologous prime-boost immunization regimens utilizing either high-dose (2 × 108 PFU) or low-dose (1 × 107 PFU) intramuscular immunization of rhesus macaques. At all time points, a majority of the HIV-specific T cell responses, elicited by all vectors, were directed against Env, rather than Gag, determinants, as previously observed with other vector systems. Both modified vectors elicited up to 6-fold-higher frequencies of HIV-specific CD8 and CD4 T cell responses and up to 25-fold-higher titers of Env (gp120)-specific binding (nonneutralizing) antibody responses that were relatively transient in nature. While the correlates of protection against HIV infection remain incompletely defined, our results indicate that the rational deletion of specific genes from MVA vectors can positively alter their cellular and humoral immunogenicity profiles in nonhuman primates. PMID:22973033

  16. The brain-specific factor FEZ1 is a determinant of neuronal susceptibility to HIV-1 infection.

    LENUS (Irish Health Repository)

    Haedicke, Juliane

    2009-08-18

    Neurons are one of the few cell types in the human body that do not support HIV type-1 (HIV-1) replication. Although the lack of key receptors is a major obstacle to infection, studies suggest that additional functions inhibit virus replication to explain the exquisite resistance of neurons to HIV-1. However, specific neuronal factors that may explain this resistance remain to be discovered. In a screen for antiviral factors using a fibroblast line chemically mutagenized and selected for resistance to retroviral infection, we recently identified induction of rat FEZ1 (fasciculation and elongation protein zeta-1), a brain-specific protein, as the cause of this resistance. When exogenously expressed in nonneuronal cell lines rat FEZ1 blocked nuclear entry of retroviral DNA. Here, we demonstrate that among human brain cells, neurons naturally express high levels of FEZ1 compared to astrocytes or microglia cells and are correspondingly less susceptible to infection with pseudotyped HIV-1 that bypasses receptor-mediated viral entry. Demonstrating that endogenous FEZ1 was functionally important in the resistance of neurons to HIV-1 infection, siRNA-mediated knockdown of endogenous FEZ1 increased the infectivity of neurons while sensitive brain cell types like microglia became more resistant upon FEZ1 overexpression. In addition, FEZ1 expression was not induced in response to IFN treatment. As such, in contrast to other widely expressed, IFN-inducible antiviral factors, FEZ1 appears to represent a unique neuron-specific determinant of cellular susceptibility to infection in a cell type that is naturally resistant to HIV-1.

  17. HIV-specific CD8+ T cells: serial killers condemned to die?

    Science.gov (United States)

    Petrovas, Constantinos; Mueller, Yvonne M; Katsikis, Peter D

    2004-04-01

    An increasing body of evidence supports a key role for cytotoxic CD8+ T cells (CTL) in controlling HIV infection. Although a vigorous HIV-specific CD8+ T cell response is raised during the primary infection, these cells ultimately fail to control virus and prevent disease progression. The failure of CTL to control HIV infection has been attributed to a number of strategies HIV employs to evade the immune system. Recently, intrinsic defects in the CTL themselves have been proposed to contribute to the failure of CTL to control HIV. HIV-specific CD8+ T cells differ in their effector/memory phenotype from other virus-specific CD8+ T cells indicating that their differentiation status differs. This altered differentiation may affect effector functions as well as homing properties of these cells. Other studies have indicated that activation of HIV-specific CTL may be impaired and this contributes to their dysfunction. The effector function of these CTL may also be affected. There are conflicting reports about their ability to kill, whereas IFNgamma production does not appear to be impaired in these cells. In this review we focus on recent work indicating that apoptosis may be an important mechanism through which HIV evades the CTL response. In particular, HIV-specific CD8+ T cells are highly susceptible to CD95/Fas-induced apoptosis. This leads to the hypothesis that virus-specific cytotoxic T cells can be eliminated upon binding CD95L/FasL on HIV-infected cells. Understanding the intrinsic defects of CTL in HIV infection could lead to new therapeutic strategies and optimized vaccination protocols that enhance the HIV-specific cytotoxic response.

  18. Critical differences in HIV-1 and HIV-2 protease specificity for clinical inhibitors.

    Science.gov (United States)

    Tie, Yunfeng; Wang, Yuan-Fang; Boross, Peter I; Chiu, Ting-Yi; Ghosh, Arun K; Tozser, Jozsef; Louis, John M; Harrison, Robert W; Weber, Irene T

    2012-03-01

    Clinical inhibitor amprenavir (APV) is less effective on HIV-2 protease (PR₂) than on HIV-1 protease (PR₁). We solved the crystal structure of PR₂ with APV at 1.5 Å resolution to identify structural changes associated with the lowered inhibition. Furthermore, we analyzed the PR₁ mutant (PR(1M) ) with substitutions V32I, I47V, and V82I that mimic the inhibitor binding site of PR₂. PR(1M) more closely resembled PR₂ than PR₁ in catalytic efficiency on four substrate peptides and inhibition by APV, whereas few differences were seen for two other substrates and inhibition by saquinavir (SQV) and darunavir (DRV). High resolution crystal structures of PR(1M) with APV, DRV, and SQV were compared with available PR₁ and PR₂ complexes. Val/Ile32 and Ile/Val47 showed compensating interactions with SQV in PR(1M) and PR₁, however, Ile82 interacted with a second SQV bound in an extension of the active site cavity of PR(1M). Residues 32 and 82 maintained similar interactions with DRV and APV in all the enzymes, whereas Val47 and Ile47 had opposing effects in the two subunits. Significantly diminished interactions were seen for the aniline of APV bound in PR₁ (M) and PR₂ relative to the strong hydrogen bonds observed in PR₁, consistent with 15- and 19-fold weaker inhibition, respectively. Overall, PR(1M) partially replicates the specificity of PR₂ and gives insight into drug resistant mutations at residues 32, 47, and 82. Moreover, this analysis provides a structural explanation for the weaker antiviral effects of APV on HIV-2. Copyright © 2012 The Protein Society.

  19. Increased sequence diversity coverage improves detection of HIV-Specific T cell responses

    DEFF Research Database (Denmark)

    Frahm, N.; Kaufmann, D.E.; Yusim, K.

    2007-01-01

    The accurate identification of HIV-specific T cell responses is important for determining the relationship between immune response, viral control, and disease progression. HIV-specific immune responses are usually measured using peptide sets based on consensus sequences, which frequently miss res...

  20. Increased sequence diversity coverage improves detection of HIV-Specific T cell responses

    DEFF Research Database (Denmark)

    Frahm, N.; Kaufmann, D.E.; Yusim, K.

    2007-01-01

    The accurate identification of HIV-specific T cell responses is important for determining the relationship between immune response, viral control, and disease progression. HIV-specific immune responses are usually measured using peptide sets based on consensus sequences, which frequently miss res...

  1. Immunological changes in human immunodeficiency virus (HIV)-infected individuals during HIV-specific protease inhibitor treatment

    DEFF Research Database (Denmark)

    Ullum, H; Katzenstein, T; Aladdin, H;

    1999-01-01

    The present study examines the influence of effective anti-retroviral treatment on immune function, evaluated by a broad array of immunological tests. We followed 12 individuals infected with human immunodeficiency virus (HIV) for 6 months after initiation of combination anti-retroviral treatment...... Vaccinia virus was increased after 3-6 months, whereas the specific HIV-directed CTL activity and the concentration and lytic activity of natural killer (NK) cells were unchanged during follow-up. These results demonstrate that the initiation of a treatment including an HIV protease inhibitor is followed...

  2. HIV-1 integrase modulates the interaction of the HIV-1 cellular cofactor LEDGF/p75 with chromatin

    Directory of Open Access Journals (Sweden)

    Garcia-Rivera Jose A

    2011-04-01

    Full Text Available Abstract Background Chromatin binding plays a central role in the molecular mechanism of LEDGF/p75 in HIV-1 DNA integration. Conflicting results have been reported in regards to the relevance of the LEDGF/p75 chromatin binding element PWWP domain in its HIV-1 cofactor activity. Results Here we present evidence that re-expression of a LEDGF/p75 mutant lacking the PWWP domain (ΔPWWP rescued HIV-1 infection in cells verified to express background levels of endogenous LEDGF/p75 that do not support efficient HIV-1 infection. The HIV-1 cofactor activity of LEDGF/p75 ΔPWWP was similar to that of LEDGF/p75 wild type (WT. A possible molecular explanation for the nonessential role of PWWP domain in the HIV-1 cofactor activity of LEDGF/p75 comes from the fact that coexpression of HIV-1 integrase significantly restored the impaired chromatin binding activity of LEDGF/p75 ΔPWWP. However, integrase failed to promote chromatin binding of a non-chromatin bound LEDGF/p75 mutant that lacks both the PWWP domain and the AT hook motifs (ΔPWWP/AT and that exhibits negligible HIV-1 cofactor activity. The effect of integrase on the chromatin binding of LEDGF/p75 requires the direct interaction of these two proteins. An HIV-1 integrase mutant, unable to interact with LEDGF/p75, failed to enhance chromatin binding, whereas integrase wild type did not increase the chromatin binding strength of a LEDGF/p75 mutant lacking the integrase binding domain (ΔIBD. Conclusions Our data reveal that the PWWP domain of LEDGF/p75 is not essential for its HIV-1 cofactor activity, possibly due to an integrase-mediated increase of the chromatin binding strength of this LEDGF/p75 mutant.

  3. HIV-1 integrase modulates the interaction of the HIV-1 cellular cofactor LEDGF/p75 with chromatin.

    Science.gov (United States)

    Astiazaran, Paulina; Bueno, Murilo Td; Morales, Elisa; Kugelman, Jeffrey R; Garcia-Rivera, Jose A; Llano, Manuel

    2011-04-21

    Chromatin binding plays a central role in the molecular mechanism of LEDGF/p75 in HIV-1 DNA integration. Conflicting results have been reported in regards to the relevance of the LEDGF/p75 chromatin binding element PWWP domain in its HIV-1 cofactor activity. Here we present evidence that re-expression of a LEDGF/p75 mutant lacking the PWWP domain (ΔPWWP) rescued HIV-1 infection in cells verified to express background levels of endogenous LEDGF/p75 that do not support efficient HIV-1 infection. The HIV-1 cofactor activity of LEDGF/p75 ΔPWWP was similar to that of LEDGF/p75 wild type (WT). A possible molecular explanation for the nonessential role of PWWP domain in the HIV-1 cofactor activity of LEDGF/p75 comes from the fact that coexpression of HIV-1 integrase significantly restored the impaired chromatin binding activity of LEDGF/p75 ΔPWWP. However, integrase failed to promote chromatin binding of a non-chromatin bound LEDGF/p75 mutant that lacks both the PWWP domain and the AT hook motifs (ΔPWWP/AT) and that exhibits negligible HIV-1 cofactor activity. The effect of integrase on the chromatin binding of LEDGF/p75 requires the direct interaction of these two proteins. An HIV-1 integrase mutant, unable to interact with LEDGF/p75, failed to enhance chromatin binding, whereas integrase wild type did not increase the chromatin binding strength of a LEDGF/p75 mutant lacking the integrase binding domain (ΔIBD). Our data reveal that the PWWP domain of LEDGF/p75 is not essential for its HIV-1 cofactor activity, possibly due to an integrase-mediated increase of the chromatin binding strength of this LEDGF/p75 mutant.

  4. Sargassum fusiforme fraction is a potent and specific inhibitor of HIV-1 fusion and reverse transcriptase.

    Science.gov (United States)

    Paskaleva, Elena E; Lin, Xudong; Duus, Karen; McSharry, James J; Veille, Jean-Claude L; Thornber, Carol; Liu, Yanze; Lee, David Yu-Wei; Canki, Mario

    2008-01-15

    Sargassum fusiforme (Harvey) Setchell has been shown to be a highly effective inhibitor of HIV-1 infection. To identify its mechanism of action, we performed bioactivity-guided fractionation on Sargassum fusiforme mixture. Here, we report isolation of a bioactive fraction SP4-2 (S. fusiforme), which at 8 mug/ml inhibited HIV-1 infection by 86.9%, with IC50 value of 3.7 mug. That represents 230-fold enhancement of antiretroviral potency as compared to the whole extract. Inhibition was mediated against both CXCR4 (X4) and CCR5 (R5) tropic HIV-1. Specifically, 10 mug/ml SP4-2 blocked HIV-1 fusion and entry by 53%. This effect was reversed by interaction of SP4-2 with sCD4, suggesting that S. fusiforme inhibits HIV-1 infection by blocking CD4 receptor, which also explained observed inhibition of both X4 and R5-tropic HIV-1. SP4-2 also inhibited HIV-1 replication after virus entry, by directly inhibiting HIV-1 reverse transcriptase (RT) in a dose dependent manner by up to 79%. We conclude that the SP4-2 fraction contains at least two distinct and biologically active molecules, one that inhibits HIV-1 fusion by interacting with CD4 receptor, and another that directly inhibits HIV-1 RT. We propose that S. fusiforme is a lead candidate for anti-HIV-1 drug development.

  5. Sargassum fusiforme fraction is a potent and specific inhibitor of HIV-1 fusion and reverse transcriptase

    Directory of Open Access Journals (Sweden)

    Thornber Carol

    2008-01-01

    Full Text Available Abstract Sargassum fusiforme (Harvey Setchell has been shown to be a highly effective inhibitor of HIV-1 infection. To identify its mechanism of action, we performed bioactivity-guided fractionation on Sargassum fusiforme mixture. Here, we report isolation of a bioactive fraction SP4-2 (S. fusiforme, which at 8 μg/ml inhibited HIV-1 infection by 86.9%, with IC50 value of 3.7 μg. That represents 230-fold enhancement of antiretroviral potency as compared to the whole extract. Inhibition was mediated against both CXCR4 (X4 and CCR5 (R5 tropic HIV-1. Specifically, 10 μg/ml SP4-2 blocked HIV-1 fusion and entry by 53%. This effect was reversed by interaction of SP4-2 with sCD4, suggesting that S. fusiforme inhibits HIV-1 infection by blocking CD4 receptor, which also explained observed inhibition of both X4 and R5-tropic HIV-1. SP4-2 also inhibited HIV-1 replication after virus entry, by directly inhibiting HIV-1 reverse transcriptase (RT in a dose dependent manner by up to 79%. We conclude that the SP4-2 fraction contains at least two distinct and biologically active molecules, one that inhibits HIV-1 fusion by interacting with CD4 receptor, and another that directly inhibits HIV-1 RT. We propose that S. fusiforme is a lead candidate for anti-HIV-1 drug development.

  6. Effect of maraviroc intensification on HIV-1-specific T cell immunity in recently HIV-1-infected individuals.

    Directory of Open Access Journals (Sweden)

    Ai Kawana-Tachikawa

    Full Text Available BACKGROUND: The effect of maraviroc on the maintenance and the function of HIV-1-specific T cell responses remains unknown. METHODS: Subjects recently infected with HIV-1 were randomized to receive anti-retroviral treatment with or without maraviroc intensification for 48 weeks, and were monitored up to week 60. PBMC and in vitro-expanded T cells were tested for responses to the entire HIV proteome by ELISpot analyses. Intracellular cytokine staining assays were conducted to monitor the (poly-functionality of HIV-1-specific T cells. Analyses were performed at baseline and week 24 after treatment start, and at week 60 (3 months after maraviroc discontinuation. RESULTS: Maraviroc intensification was associated with a slower decay of virus-specific T cell responses over time compared to the non-intensified regimen in both direct ex-vivo as well as in in-vitro expanded cells. The effector function profiles of virus-specific CD8⁺ T cells were indistinguishable between the two arms and did not change over time between the groups. CONCLUSIONS: Maraviroc did not negatively impact any of the measured parameters, but was rather associated with a prolonged maintenance of HIV-1-specific T cell responses. Maraviroc, in addition to its original effect as viral entry inhibitor, may provide an additional benefit on the maintenance of virus-specific T cells which may be especially important for future viral eradication strategies.

  7. Structure of cellular ESCRT-III spirals and their relationship to HIV budding.

    Science.gov (United States)

    Cashikar, Anil G; Shim, Soomin; Roth, Robyn; Maldazys, Michael R; Heuser, John E; Hanson, Phyllis I

    2014-05-30

    The ESCRT machinery along with the AAA+ ATPase Vps4 drive membrane scission for trafficking into multivesicular bodies in the endocytic pathway and for the topologically related processes of viral budding and cytokinesis, but how they accomplish this remains unclear. Using deep-etch electron microscopy, we find that endogenous ESCRT-III filaments stabilized by depleting cells of Vps4 create uniform membrane-deforming conical spirals which are assemblies of specific ESCRT-III heteropolymers. To explore functional roles for ESCRT-III filaments, we examine HIV-1 Gag-mediated budding of virus-like particles and find that depleting Vps4 traps ESCRT-III filaments around nascent Gag assemblies. Interpolating between the observed structures suggests a new role for Vps4 in separating ESCRT-III from Gag or other cargo to allow centripetal growth of a neck constricting ESCRT-III spiral.

  8. Discovery of the first small molecule inhibitor of human DDX3 specifically designed to target the RNA binding site: towards the next generation HIV-1 inhibitors.

    Science.gov (United States)

    Radi, Marco; Falchi, Federico; Garbelli, Anna; Samuele, Alberta; Bernardo, Vincenzo; Paolucci, Stefania; Baldanti, Fausto; Schenone, Silvia; Manetti, Fabrizio; Maga, Giovanni; Botta, Maurizio

    2012-03-01

    Efficacy of currently approved anti-HIV drugs is hampered by mutations of the viral enzymes, leading invariably to drug resistance and chemotherapy failure. Recent data suggest that cellular co-factors also represent useful targets for anti-HIV therapy. Here we describe the identification of the first small molecules specifically designed to inhibit the HIV-1 replication by targeting the RNA binding site of the human DEAD-Box RNA helicase DDX3. Optimization of a easily synthetically accessible hit (1) identified by application of a high-throughput docking approach afforded the promising compounds 6 and 8 which proved to inhibit both the helicase and ATPase activity of DDX3 and to reduce the viral load of peripheral blood mononuclear cells (PBMC) infected with HIV-1.

  9. Independent evolution of Fc- and Fab-mediated HIV-1-specific antiviral antibody activity following acute infection

    Science.gov (United States)

    Dugast, Anne-Sophie; Stamatatos, Leonidas; Tonelli, Andrew; Suscovich, Todd J.; Licht, Anna F.; Mikell, Iliyana; Ackerman, Margaret E.; Streeck, Hendrik; Klasse, P.J.; Moore, John P.; Alter, Galit

    2014-01-01

    Fc-related antibody activities, such as antibody-dependent cellular cytotoxicity (ADCC), or more broadly, antibody-mediated cellular viral inhibition (ADCVI), play a role in curbing early SIV viral replication, are enriched in human long-term infected non-progressors, and could potentially contribute to protection from infection. However, little is known about the mechanism by which such humoral immune responses are naturally induced following infection. Here we focused on the early evolution of the functional antibody response, largely driven by the Fc portion of the antibody, in the context of the evolving binding and neutralizing antibody response, which is driven mainly by the antibody binding fragment (Fab). We show that ADCVI/ADCC-inducing responses in humans are rapidly generated following acute HIV-1 infection, peak at approximately 6 months post-infection, but decay rapidly in the setting of persistent immune activation, as Fab-related activities persistently increase. Moreover, the loss of Fc activity occurred in synchrony with a loss of HIV-specific IgG3 responses. Our data strongly suggest that Fc- and Fab-related antibody functions are modulated in a distinct manner following acute HIV infection. Vaccination strategies intended to optimally induce both sets of antiviral antibody activities may, therefore, require a fine-tuning of the inflammatory response. PMID:25043633

  10. Adaptive HIV-specific B cell-derived humoral immune defenses of the intestinal mucosa in children exposed to HIV via breast-feeding.

    Directory of Open Access Journals (Sweden)

    Sandrine Moussa

    Full Text Available BACKGROUND: We evaluated whether B cell-derived immune defenses of the gastro-intestinal tract are activated to produce HIV-specific antibodies in children continuously exposed to HIV via breast-feeding. METHODS: Couples of HIV-1-infected mothers (n = 14 and their breastfed non HIV-infected (n = 8 and HIV-infected (n = 6 babies, and healthy HIV-negative mothers and breastfed babies (n = 10 as controls, were prospectively included at the Complexe Pédiatrique of Bangui, Central African Republic. Immunoglobulins (IgA, IgG and IgM and anti-gp160 antibodies from mother's milk and stools of breastfed children were quantified by ELISA. Immunoaffinity purified anti-gp160 antibodies were characterized functionally regarding their capacity to reduce attachment and/or infection of R5- and X4- tropic HIV-1 strains on human colorectal epithelial HT29 cells line or monocyte-derived-macrophages (MDM. RESULTS: The levels of total IgA and IgG were increased in milk of HIV-infected mothers and stools of HIV-exposed children, indicating the activation of B cell-derived mucosal immunity. Breast milk samples as well as stool samples from HIV-negative and HIV-infected babies exposed to HIV by breast-feeding, contained high levels of HIV-specific antibodies, mainly IgG antibodies, less frequently IgA antibodies, and rarely IgM antibodies. Relative ratios of excretion by reference to lactoferrin calculated for HIV-specific IgA, IgG and IgM in stools of HIV-exposed children were largely superior to 1, indicating active production of HIV-specific antibodies by the intestinal mucosa. Antibodies to gp160 purified from pooled stools of HIV-exposed breastfed children inhibited the attachment of HIV-1NDK on HT29 cells by 63% and on MDM by 77%, and the attachment of HIV-1JRCSF on MDM by 40%; and the infection of MDM by HIV-1JRCSF by 93%. CONCLUSIONS: The intestinal mucosa of children exposed to HIV by breast-feeding produces HIV-specific antibodies harbouring

  11. Computer-based design of an HLA-haplotype and HIV-clade independent cytotoxic T-lymphocyte assay for monitoring HIV-specific immunity.

    Science.gov (United States)

    Amicosante, Massimo; Gioia, Cristiana; Montesano, Carla; Casetti, Rita; Topino, Simone; D'Offizi, Gianpiero; Cappelli, Giulia; Ippolito, Giuseppe; Colizzi, Vittorio; Poccia, Fabrizio; Pucillo, Leopoldo P.

    2002-01-01

    BACKGROUND: Human immunodeficiency virus (HIV)- specific CD8-positive cytotoxic T-lymphocytes (CTL) play a key role in controlling HIV infection. Monitoring CTL response could be clinically relevant during structured therapy interruption (STI), HIV exposure, and vaccine trials. However, HLA patients' restriction and HIV variability limited the development of a CTL assay with broad specificity. MATERIALS AND METHODS: We designed an HLA-class I/HIV-1 clade independent assay for assessing HIV- specific CTL by using a computer-assisted selection ofthe CTL epitopes. Twenty-eight 15-mers were selected by peptide-binding motifs analysis using different databases (HIV-Immunology Database, SYFPEITHI, BIMAS). Altogether they putatively bind to more than 90% of HLA haplotypes in different populations, with an overall HIV-1 variability below 9%. The peptide pool was used as an antigen in an intracellular cytokine staining (ICS) assay for quantifying HIV-specific CTL response. RESULTS: The test can be performed using both fresh and cryopreserved peripheral blood mononuclear cells (PBMC), whereas GAG protein as antigen works only on fresh PBMC. A significantly higher CTL response with respect to HIV-negative controls was detected in all HIV-1 infected subjects of two groups of patients with different ethnicities (Caucasians and Africans) and coming from areas with different HIV-1 clade prevalences (clade B and A/G, respectively). In Caucasian patients, after month of STI, the number of HIV-1 specific CTL (2,896 +/- 2,780 IFN-gamma specific CD8 cells/ml) was significantly higher than that found at enrolment (2,125 +/- 4,426 IFN-gamma specific CD8 cells/ml, p< 0.05). CONCLUSIONS: These data indicate that this CTL assay is broadly specific and could represent a useful clinical tool for HIV immunodiagnostic independent of HLA-haplotype and HIV-clade variabilities. PMID:12606814

  12. HIV-1 production is specifically associated with human NMT1 long form in human NMT isozymes.

    Science.gov (United States)

    Takamune, Nobutoki; Gota, Kayoko; Misumi, Shogo; Tanaka, Kenzo; Okinaka, Shigetaka; Shoji, Shozo

    2008-02-01

    The N-myristoylation of the N-terminal of human immunodeficiency virus type-1 (HIV-1) Pr55(gag) by human N-myristoyltransferase (hNMT) is a prerequisite modification for HIV-1 production. hNMT consists of multiple isozymes encoded by hNMT1 and hNMT2. The hNMT1 isozyme consists of long, medium, and short forms. Here, we investigated which isozyme is crucial for HIV-1 production. Human embryonic kidney (HEK) 293 cells transfected with infectious HIV-1 vectors were used as models of HIV-1-infected cells in this study. The significant reduction in HIV-1 production and the failure of the specific localization of Pr55(gag) in a detergent-resistant membrane fraction were dependent on the knockdown of the different forms of the hNMT1 isozyme but not of the hNMT2 isozyme. Additionally, the coexpression of an inactive mutant hNMT1 isozyme, namely the hNMT1 long form (hNMT1(L)), but not that of other hNMT mutants resulted in a significant reduction in HIV-1 production. These results strongly suggest that HIV-1 production is specifically associated with hNMT1, particularly hNMT1(L), but not with hNMT2 in vivo, contributing to the understanding of a step in HIV-1 replication.

  13. Identification and specificity of broadly neutralizing antibodies against HIV

    OpenAIRE

    McCoy, Laura E.; Burton, Dennis R.

    2017-01-01

    Summary Beginning in 2009, studies of the humoral responses of HIV‐positive individuals have led to the identification of scores, if not hundreds, of antibodies that are both broadly reactive and potently neutralizing. This development has provided renewed impetus toward an HIV vaccine and led directly to the development of novel immunogens. Advances in identification of donors with the most potent and broad anti‐HIV serum neutralizing responses were crucial in this effort. Equally, developme...

  14. Intermolecular masking of the HIV-1 Rev NLS by the cellular protein HIC: Novel insights into the regulation of Rev nuclear import.

    LENUS (Irish Health Repository)

    Gu, Lili

    2011-03-14

    Abstract Background The HIV-1 regulatory protein Rev, which is essential for viral replication, mediates the nuclear export of unspliced viral transcripts. Rev nuclear function requires active nucleocytoplasmic shuttling, and Rev nuclear import is mediated by the recognition of its Nuclear Localisation Signal (NLS) by multiple import factors, which include transportin and importin β. However, it remains unclear which nuclear import pathway(s) predominate in vivo, and the cellular environment that modulates Rev nucleocytoplasmic shuttling remains to be characterised. Results In our study, we have identified the cellular protein HIC (Human I-mfa domain-Containing protein) as a novel interactor of HIV-1 Rev. We demonstrate that HIC selectively interferes with Rev NLS interaction with importin β and impedes its nuclear import and function, but does not affect Rev nuclear import mediated by transportin. Hence, the molecular determinants mediating Rev-NLS recognition by importin β and transportin appear to be distinct. Furthermore, we have employed HIC and M9 M, a peptide specifically designed to inhibit the transportin-mediated nuclear import pathway, to characterise Rev nuclear import pathways within different cellular environments. Remarkably, we could show that in 293T, HeLa, COS7, Jurkat, U937, THP-1 and CEM cells, Rev nuclear import is cell type specific and alternatively mediated by transportin or importin β, in a mutually exclusive fashion. Conclusions Rev cytoplasmic sequestration by HIC may represent a novel mechanism for the control of Rev function. These studies highlight that the multivalent nature of the Rev NLS for different import receptors enables Rev to adapt its nuclear trafficking strategy.

  15. Intermolecular masking of the HIV-1 Rev NLS by the cellular protein HIC: Novel insights into the regulation of Rev nuclear import

    Directory of Open Access Journals (Sweden)

    Sheehy Noreen

    2011-03-01

    Full Text Available Abstract Background The HIV-1 regulatory protein Rev, which is essential for viral replication, mediates the nuclear export of unspliced viral transcripts. Rev nuclear function requires active nucleocytoplasmic shuttling, and Rev nuclear import is mediated by the recognition of its Nuclear Localisation Signal (NLS by multiple import factors, which include transportin and importin β. However, it remains unclear which nuclear import pathway(s predominate in vivo, and the cellular environment that modulates Rev nucleocytoplasmic shuttling remains to be characterised. Results In our study, we have identified the cellular protein HIC (Human I-mfa domain-Containing protein as a novel interactor of HIV-1 Rev. We demonstrate that HIC selectively interferes with Rev NLS interaction with importin β and impedes its nuclear import and function, but does not affect Rev nuclear import mediated by transportin. Hence, the molecular determinants mediating Rev-NLS recognition by importin β and transportin appear to be distinct. Furthermore, we have employed HIC and M9 M, a peptide specifically designed to inhibit the transportin-mediated nuclear import pathway, to characterise Rev nuclear import pathways within different cellular environments. Remarkably, we could show that in 293T, HeLa, COS7, Jurkat, U937, THP-1 and CEM cells, Rev nuclear import is cell type specific and alternatively mediated by transportin or importin β, in a mutually exclusive fashion. Conclusions Rev cytoplasmic sequestration by HIC may represent a novel mechanism for the control of Rev function. These studies highlight that the multivalent nature of the Rev NLS for different import receptors enables Rev to adapt its nuclear trafficking strategy.

  16. Prevalence of autoantibodies against cellular antigens in patients with HIV and leprosy coinfection in the Amazon region.

    Science.gov (United States)

    Bichara, Clea Nazaré Carneiro; Bichara, Carlos David Araújo; Tostes, Camila; Povoa, Marinete Marins; Quaresma, Juarez Antonio Simões; Xavier, Marília Brasil

    2017-06-01

    Infectious agents can activate self-reactive T cells. In general, infections trigger various mechanisms, including a lack of auto-tolerance, induction of costimulatory molecules on antigen presenting cells, and molecular simulation, in addition to cross-reactions between microbial antigens and self-antigens. HIV and leprosy coinfections lead to self-immunity with the production of autoantibodies. However, not enough data on the immune behaviour associated with this coinfection are available. Therefore, this study focused on the detection of autoantibodies against cellular antigens (AACA) in individuals with HIV and leprosy coinfection in the Amazon region. Patients were distributed into four groups according to their infections: (i) coinfection with HIV and leprosy (n = 23), (ii) infection with leprosy (n = 33), (iii) infection with HIV/AIDS (n = 25), and (iv) healthy blood donor controls (n = 100). AACA were identified by indirect immunofluorescence and the samples were tested using a commercial diagnosis kit containing the antinuclear antibody HEp-2. Morphologically, all stages of cell division were assessed in addition to the morphological features associated with the nuclear matrix, nucleolus, mitotic spindle, and cytoplasm. There was a high prevalence of AACA in the coinfection group (47.8%, n = 11) when compared with the control group of healthy blood donors (2.0%). The results showed predominantly cytoplasmic staining in all groups analysed, and no difference was observed between the presence or absence of AACA and the leprosy forms (paucibacillary and multibacillary) in the coinfection group. The results of this study show that despite the tendency of coinfected patients to have higher levels of autoantibodies, no correlation was observed between clinical and laboratorial variables and morbidity associated with HIV and leprosy coinfections or the levels of AACA in the serum of coinfected patients. These data are important to elucidate

  17. Elevated Cancer-Specific Mortality Among HIV-Infected Patients in the United States.

    Science.gov (United States)

    Coghill, Anna E; Shiels, Meredith S; Suneja, Gita; Engels, Eric A

    2015-07-20

    Despite advances in the treatment of HIV, HIV-infected people remain at increased risk for many cancers, and the number of non-AIDS-defining cancers is increasing with the aging of the HIV-infected population. No prior study has comprehensively evaluated the effect of HIV on cancer-specific mortality. We identified cases of 14 common cancers occurring from 1996 to 2010 in six US states participating in a linkage of cancer and HIV/AIDS registries. We used Cox regression to examine the association between patient HIV status and death resulting from the presenting cancer (ascertained from death certificates), adjusting for age, sex, race/ethnicity, year of cancer diagnosis, and cancer stage. We included 1,816,461 patients with cancer, 6,459 (0.36%) of whom were HIV infected. Cancer-specific mortality was significantly elevated in HIV-infected compared with HIV-uninfected patients for many cancers: colorectum (adjusted hazard ratio [HR], 1.49; 95% CI, 1.21 to 1.84), pancreas (HR, 1.71; 95% CI, 1.35 to 2.18), larynx (HR, 1.62; 95% CI, 1.06 to 2.47), lung (HR, 1.28; 95% CI, 1.17 to 1.39), melanoma (HR, 1.72; 95% CI, 1.09 to 2.70), breast (HR, 2.61; 95% CI, 2.06 to 3.31), and prostate (HR, 1.57; 95% CI, 1.02 to 2.41). HIV was not associated with increased cancer-specific mortality for anal cancer, Hodgkin lymphoma, or diffuse large B-cell lymphoma. After further adjustment for cancer treatment, HIV remained associated with elevated cancer-specific mortality for common non-AIDS-defining cancers: colorectum (HR, 1.40; 95% CI, 1.09 to 1.80), lung (HR, 1.28; 95% CI, 1.14 to 1.44), melanoma (HR, 1.93; 95% CI, 1.14 to 3.27), and breast (HR, 2.64; 95% CI, 1.86 to 3.73). HIV-infected patients with cancer experienced higher cancer-specific mortality than HIV-uninfected patients, independent of cancer stage or receipt of cancer treatment. The elevation in cancer-specific mortality among HIV-infected patients may be attributable to unmeasured stage or treatment differences as well

  18. HIV-specific CD8~+ T cell responses to HXB2 Gag and Nef peptide pools in Chinese HIV/AIDS patients

    Institute of Scientific and Technical Information of China (English)

    ZHANG HongWei; QIU ZhiFeng; JIAO Yang; WANG AiXia; LI TaiSheng

    2009-01-01

    HXB2 is primarily used as a template strain in developing HIV vaccines in Europe and the US. However, it is not yet known whether the strain can induce strong HIV-specific CD8~+ T cell responses in Chinese HIV/AIDS patients. In the present study, two groups of subjects were investigated: 9 AIDS patients and 7 long-term nonprogressors (LTNPs). HIV-specific CD8~+ T cell responses were examined in all patients through the ELISPOT assay. CD4~+ T cell counts, CD8~+ T cell counts, viral load and HIV subtype of each patient were also measured. Thailand B virus strain was identified among all the patients. The breadth and magnitude of HIV-specific CD8~+ T cell responses in the LTNPs group are greater than those in the AIDS group (P<0.01). There is a positive correlation between magnitude of HIV-specific CD8~+ T cell responses and CD4~+ T cells, and a negative correlation between HIV-specific CD8~+ T cell responses and mean viral load. In summary, the HIV-specific CD8~+ T cell responses to the HXB2 Gag and Nef peptide pools are considerable in Chinese HIV/AIDS patients infected with Thailand B virus strain. HIV-1 vaccines based on HXB2 strain that can induce extensive immunity may be helpful for Chinese.

  19. HIV-specific CD8~+ T cell responses to HXB2 Gag and Nef peptide pools in Chinese HIV/AIDS patients

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    HXB2 is primarily used as a template strain in developing HIV vaccines in Europe and the US. However,it is not yet known whether the strain can induce strong HIV-specific CD8+ T cell responses in Chinese HIV/AIDS patients. In the present study,two groups of subjects were investigated:9 AIDS patients and 7 long-term nonprogressors (LTNPs). HIV-specific CD8+ T cell responses were examined in all patients through the ELISPOT assay. CD4+ T cell counts,CD8+ T cell counts,viral load and HIV subtype of each patient were also measured. Thailand B virus strain was identified among all the patients. The breadth and magnitude of HIV-specific CD8+ T cell responses in the LTNPs group are greater than those in the AIDS group (P<0.01). There is a positive correlation between magnitude of HIV-specific CD8+ T cell responses and CD4+ T cells,and a negative correlation between HIV-specific CD8+ T cell responses and mean viral load. In summary,the HIV-specific CD8+ T cell responses to the HXB2 Gag and Nef peptide pools are considerable in Chinese HIV/AIDS patients infected with Thailand B virus strain. HIV-1 vaccines based on HXB2 strain that can induce extensive immunity may be helpful for Chinese.

  20. Bridging HIV-1 cellular latency and clinical long-term non-progressor: an interactomic view.

    Directory of Open Access Journals (Sweden)

    Jin Yang

    Full Text Available Development of an effective HIV management is enticed by the fact that long-term non-progressors (LTNP restrict viral replication spontaneously, but is hindered by HIV-1 latency. Given that the most overlapping characteristics found between HIV-1 LTNP and latency, detailed analysis of the difference would disclose the essentials of latency. In this study, microarray data from our previous study was combined with HIV-1 latency and LTNP data obtained from NCBI GEO database. Principal variance component analysis and hierarchical clustering verified the removal of batch effect across platform. The analysis revealed a total of 456 differential expressed genes with >2-fold change and B-statistic >0. Bayesian inference was used to reconstitute the transcriptional network of HIV-1 latency or LTNP, respectively. Gene regulation was reprogrammed under different disease condition. By network interference, KPNA2 and ATP5G3 were identified as the hubs in latency network which mediate nuclear export and RNA processing. These data offer comparative insights into HIV-1 latency, which will facilitate the understanding of the genetic basis of HIV-1 latency in vivo and serve as a clue for future treatment dealing with key targets in HIV-1 latency.

  1. HIV aspartyl peptidase inhibitors interfere with cellular proliferation, ultrastructure and macrophage infection of Leishmania amazonensis.

    Directory of Open Access Journals (Sweden)

    Lívia O Santos

    Full Text Available BACKGROUND: Leishmania is the etiologic agent of leishmanisais, a protozoan disease whose pathogenic events are not well understood. Current therapy is suboptimal due to toxicity of the available therapeutic agents and the emergence of drug resistance. Compounding these problems is the increase in the number of cases of Leishmania-HIV coinfection, due to the overlap between the AIDS epidemic and leishmaniasis. METHODOLOGY/PRINCIPAL FINDINGS: In the present report, we have investigated the effect of HIV aspartyl peptidase inhibitors (PIs on the Leishmania amazonensis proliferation, ultrastructure, interaction with macrophage cells and expression of classical peptidases which are directly involved in the Leishmania pathogenesis. All the HIV PIs impaired parasite growth in a dose-dependent fashion, especially nelfinavir and lopinavir. HIV PIs treatment caused profound changes in the leishmania ultrastructure as shown by transmission electron microscopy, including cytoplasm shrinking, increase in the number of lipid inclusions and some cells presenting the nucleus closely wrapped by endoplasmic reticulum resembling an autophagic process, as well as chromatin condensation which is suggestive of apoptotic death. The hydrolysis of HIV peptidase substrate by L. amazonensis extract was inhibited by pepstatin and HIV PIs, suggesting that an aspartyl peptidase may be the intracellular target of the inhibitors. The treatment with HIV PIs of either the promastigote forms preceding the interaction with macrophage cells or the amastigote forms inside macrophages drastically reduced the association indexes. Despite all these beneficial effects, the HIV PIs induced an increase in the expression of cysteine peptidase b (cpb and the metallopeptidase gp63, two well-known virulence factors expressed by Leishmania spp. CONCLUSIONS/SIGNIFICANCE: In the face of leishmaniasis/HIV overlap, it is critical to further comprehend the sophisticated interplays among Leishmania

  2. Universal Tre (uTre recombinase specifically targets the majority of HIV-1 isolates

    Directory of Open Access Journals (Sweden)

    Janet Karpinski

    2014-11-01

    Full Text Available Current drugs against HIV can suppress the progression to AIDS but cannot clear the patient from the virus. Because of potential side effects of these drugs and the possible development of drug resistance, finding a cure for HIV infection remains a high priority of HIV/AIDS research. We recently generated a recombinase (termed Tre tailored to efficiently eradicate the provirus from the host genome of HIV-1 infected cells by specifically targeting a sequence that is present in the long terminal repeats (LTRs of the viral DNA [1]. In vivo analyses in HIV-infected humanized mice demonstrated highly significant antiviral effects of Tre recombinase [2]. However, the fact that Tre recognizes a particular HIV-1 subtype A strain may limit its broad therapeutic application. To advance our Tre-based strategy towards a universally efficient cure, we have engineered a new, universal recombinase (uTre applicable to the majority of HIV-1 infections by the various virus strains and subtypes. We employed the search tool SeLOX [3] in order to find a well-conserved HIV-1 proviral sequence that could serve as target site for a universal Tre from sequences compiled in the Los Alamos HIV Sequence Database. We selected a candidate (termed loxLTRu with a mean conservation rate of 94% throughout the major HIV-1 subtype groups A, B and C. We applied loxLTRu as substrate in our established substrate-linked protein evolution (SLiPE process [4] and evolved the uTre recombinase in 142 evolution cycles. Highly specific enzymatic activity on loxLTRu is demonstrated for uTre in both Escherichia coli and human cells. Naturally occurring viral variants with single mutations within the loxLTRu sequence are also shown to be efficiently targeted by uTre, further increasing the range of applicability of the recombinase. Potential off-target sites in the human genome are not recombined by uTre. Furthermore, uTre expression in primary human T cells shows no obvious Tre

  3. Non-coding RNAs and HIV: viral manipulation of host dark matter to shape the cellular environment.

    Science.gov (United States)

    Barichievy, Samantha; Naidoo, Jerolen; Mhlanga, Musa M

    2015-01-01

    On October 28th 1943 Winston Churchill said "we shape our buildings, and afterward our buildings shape us" (Humes, 1994). Churchill was pondering how and when to rebuild the British House of Commons, which had been destroyed by enemy bombs on May 10th 1941. The old House had been small and insufficient to hold all its members, but was restored to its original form in 1950 in order to recapture the "convenience and dignity" that the building had shaped into its parliamentary members. The circular loop whereby buildings or dwellings are shaped and go on to shape those that reside in them is also true of pathogens and their hosts. As obligate parasites, pathogens need to alter their cellular host environments to ensure survival. Typically pathogens modify cellular transcription profiles and in doing so, the pathogen in turn is affected, thereby closing the loop. As key orchestrators of gene expression, non-coding RNAs provide a vast and extremely precise set of tools for pathogens to target in order to shape the cellular environment. This review will focus on host non-coding RNAs that are manipulated by the infamous intracellular pathogen, the human immunodeficiency virus (HIV). We will briefly describe both short and long host non-coding RNAs and discuss how HIV gains control of these factors to ensure widespread dissemination throughout the host as well as the establishment of lifelong, chronic infection.

  4. Application of Radial Basis Network Model for HIV/AIDs Regimen Specifications

    CERN Document Server

    Balasubramanie, P

    2009-01-01

    HIV/AIDs Regimen specification one of many problems for which bioinformaticians have implemented and trained machine learning methods such as neural networks. Predicting HIV resistance would be much easier, but unfortunately we rarely have enough structural information available to train a neural network. To network model designed to predict how long the HIV patient can prolong his/her life time with certain regimen specification. To learn this model 300 patient's details have taken as a training set to train the network and 100 patients medical history has taken to test this model. This network model is trained using MAT lab implementation.

  5. Structural basis of evasion of cellular adaptive immunity by HIV-1 Nef

    Energy Technology Data Exchange (ETDEWEB)

    Jia, Xiaofei; Singh, Rajendra; Homann, Stefanie; Yang, Haitao; Guatelli, John; Xiong, Yong (Yale); (VA); (UCSD)

    2012-10-24

    The HIV-1 protein Nef inhibits antigen presentation by class I major histocompatibility complex (MHC-I). We determined the mechanism of this activity by solving the crystal structure of a protein complex comprising Nef, the MHC-I cytoplasmic domain (MHC-I CD) and the {mu}1 subunit of the clathrin adaptor protein complex 1. A ternary, cooperative interaction clamps the MHC-I CD into a narrow binding groove at the Nef-{mu}1 interface, which encompasses the cargo-recognition site of {mu}1 and the proline-rich strand of Nef. The Nef C terminus induces a previously unobserved conformational change in {mu}1, whereas the N terminus binds the Nef core to position it optimally for complex formation. Positively charged patches on {mu}1 recognize acidic clusters in Nef and MHC-I. The structure shows how Nef functions as a clathrin-associated sorting protein to alter the specificity of host membrane trafficking and enable viral evasion of adaptive immunity.

  6. Restricted isotype, distinct variable gene usage, and high rate of gp120 specificity of HIV-1 envelope-specific B cells in colostrum compared with those in blood of HIV-1-infected, lactating African women.

    Science.gov (United States)

    Sacha, C R; Vandergrift, N; Jeffries, T L; McGuire, E; Fouda, G G; Liebl, B; Marshall, D J; Gurley, T C; Stiegel, L; Whitesides, J F; Friedman, J; Badiabo, A; Foulger, A; Yates, N L; Tomaras, G D; Kepler, T B; Liao, H X; Haynes, B F; Moody, M A; Permar, S R

    2015-03-01

    A successful HIV-1 vaccine must elicit immune responses that impede mucosal virus transmission, though functional roles of protective HIV-1 Envelope (Env)-specific mucosal antibodies remain unclear. Colostrum is a rich source of readily accessible mucosal B cells that may help define the mucosal antibody response contributing to prevention of postnatal HIV-1 transmission. To examine the HIV-1 Env-specific colostrum B-cell repertoire, single B cells were isolated from 17 chronically HIV-infected, lactating women, producing 51 blood and 39 colostrum HIV-1 Env-specific B-cell antibodies. All HIV-1 Env-specific colostrum-derived antibodies were immunoglobulin (Ig)G1 isotype and had mean heavy chain complementarity-determining region 3 (CDR3) lengths and mutation frequencies similar to those isolated from blood. However, variable heavy chain (VH) gene subfamily 1(∼)69 usage was higher among colostrum than blood HIV-1 Env-reactive antibodies (49% vs. 20%, P=0.006, Fisher's exact test). Additionally, more HIV-1 Env-specific colostrum antibodies were gp120 specific than those isolated from blood (44% vs. 16%, P=0.005, Fisher's exact test). One cross-compartment HIV-1 Env-specific clonal B-cell lineage was identified. These unique characteristics of colostrum B-cell antibodies suggest selective homing of HIV-1-specific IgG1-secreting memory B cells to the mammary gland and have implications for targeting mucosal B-cell populations by vaccination.

  7. The impact of pregnancy on the HIV-1-specific T cell function in infected pregnant women.

    Science.gov (United States)

    Hygino, Joana; Vieira, Morgana M; Kasahara, Taissa M; Xavier, Luciana F; Blanco, Bernardo; Guillermo, Landi V C; Filho, Renato G S; Saramago, Carmen S M; Lima-Silva, Agostinho A; Oliveira, Ariane L; Guimarães, Vander; Andrade, Arnaldo F B; Bento, Cleonice A M

    2012-12-01

    Evidences indicate that pregnancy can alter the Ag-specific T-cell responses. This work aims to evaluate the impact of pregnancy on the in vitro HIV-1-specific immune response. As compared with non-pregnant patients, lower T-cell proliferation and higher IL-10 production were observed in T-cell cultures from pregnant patients following addition of either mitogens or HIV-1 antigens. In our system, the main T lymphocyte subset involved in producing IL-10 was CD4(+)FoxP3(-). Depletion of CD4(+) cells elevated TNF-α and IFN-γ production. Interestingly, the in vitro HIV-1 replication was lower in cell cultures from pregnant patients, and it was inversely related to IL-10 production. In these cultures, the neutralization of IL-10 by anti-IL-10 mAb elevated TNF-α release and HIV-1 replication. In conclusion, our results reveal that pregnancy-related events should favor the expansion of HIV-1-specific IL-10-secreting CD4(+) T-cells in HIV-1-infected women, which should, in the scenario of pregnancy, help to reduce the risk of vertical HIV-1 transmission.

  8. Control of Directional Macromolecular Trafficking Across Specific Cellular Boundaries: A Key to Integrative Plant Biology

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    There is now solid evidence that cell-to-cell trafficking of certain proteins and RNAs plays a critical role in trans-cellular regulation of gene expression to coordinate cellular differentiation and development. Such trafficking also is critical for viral infection and plant defense. The mechanisms of trafficking remain poorly understood. Although some proteins may move between cells by diffusion, many proteins and RNAs move in a highly regulated fashion. Regulation is likely achieved through interactions between distinct protein or RNA motifs and cellular factors. Some motifs and factors have been identified. One of the major focuses for future studies is to identify all motifs and their cognate factors and further elucidate their roles in trafficking between specific cells. With increasing information from such studies, we should be able to develop an understanding of the mechanisms that regulate trafficking of various proteins and RNAs across all and specific cellular boundaries. On the basis of such mechanistic knowledge, we can further investigate how the trafficking machinery has evolved to regulate developmental and physiological processes in a plant, how pathogens have co-evolved to use this machinery for systemic spread in a plant, and how plants use this machinery for counterdefense.

  9. Cellular automata approach for the dynamics of HIV infection under antiretroviral therapies: The role of the virus diffusion

    Science.gov (United States)

    González, Ramón E. R.; de Figueirêdo, Pedro Hugo; Coutinho, Sérgio

    2013-10-01

    We study a cellular automata model to test the timing of antiretroviral therapy strategies for the dynamics of infection with human immunodeficiency virus (HIV). We focus on the role of virus diffusion when its population is included in previous cellular automata model that describes the dynamics of the lymphocytes cells population during infection. This inclusion allows us to consider the spread of infection by the virus-cell interaction, beyond that which occurs by cell-cell contagion. The results show an acceleration of the infectious process in the absence of treatment, but show better efficiency in reducing the risk of the onset of AIDS when combined antiretroviral therapies are used even with drugs of low effectiveness. Comparison of results with clinical data supports the conclusions of this study.

  10. Subset- and Antigen-Specific Effects of Treg on CD8+ T Cell Responses in Chronic HIV Infection.

    Science.gov (United States)

    Nikolova, Maria; Wiedemann, Aurélie; Muhtarova, Maria; Achkova, Daniela; Lacabaratz, Christine; Lévy, Yves

    2016-11-01

    We, and others, have reported that in the HIV-negative settings, regulatory CD4+CD25highFoxP3+ T cells (Treg) exert differential effects on CD8 subsets, and maintain the memory / effector CD8+ T cells balance, at least in part through the PD-1/PD-L1 pathway. Here we investigated Treg-mediated effects on CD8 responses in chronic HIV infection. As compared to Treg from HIV negative controls (Treg/HIV-), we show that Treg from HIV infected patients (Treg/HIV+) did not significantly inhibit polyclonal autologous CD8+ T cell function indicating either a defect in the suppressive capacity of Treg/HIV+ or a lack of sensitivity of effector T cells in HIV infection. Results showed that Treg/HIV+ inhibited significantly the IFN-γ expression of autologous CD8+ T cells stimulated with recall CMV/EBV/Flu (CEF) antigens, but did not inhibit HIV-Gag-specific CD8+ T cells. In cross-over cultures, we show that Treg/HIV- inhibited significantly the differentiation of either CEF- or Gag-specific CD8+ T cells from HIV infected patients. The expression of PD-1 and PD-L1 was higher on Gag-specific CD8+ T cells as compared to CEF-specific CD8+ T cells, and the expression of these markers did not change significantly after Treg depletion or co-culture with Treg/HIV-, unlike on CEF-specific CD8+ T cells. In summary, we show a defect of Treg/HIV+ in modulating both the differentiation and the expression of PD-1/PD-L1 molecules on HIV-specific CD8 T cells. Our results strongly suggest that this particular defect of Treg might contribute to the exhaustion of HIV-specific T cell responses.

  11. Clonal priming of human lymphocytes: Specificity and cross-reactivity of cellular immune reactions.

    Science.gov (United States)

    Levis, W R; Datiner, A M

    1977-04-23

    Clonal priming in response to chemical and microbial antigens which defines the specificity of cellular immune reactions, was demonstrated by culture techniques. Human leucocyte cultures stimulated with specific antigens typically show peak levels of D.N.A. synthesis after 5 to 7 days in culture. Such primary leucocyte cultures were incubated for 10-20 days, then the cells were gently centrifuged and resuspended in fresh RPMI 1640 with 20% plasma. These secondary or primed cultures typically showed less than 1000 c.p.m. after 48 hours. However, if the original antigenic stimulant was added, specific accelerated responses were seen by 48 hours in the secondary cultures. Lymphocyte clones in these sceondary cultures primed with dinitrophenylated (D.N.P.) antigens (from subjects sensitised to dinitrochlorobenzene) showed enhanced D.N.A. sythesis in response to the same dinitrophenylated antigens and showed varible accelerated responses to related chemically modified antigens. However, D.N.P.-activated clones in these secondary cultures did not show enhanced responses to microbial antigens even though the lymphocytes had been highly responsive to tetanus toxoid and other microbial antigens in primary cultures. The specificity of this clonal activation was further demonstrated by the enhanced response of secondary cultures of tetanus-toxoid-activated clones to tetanus toxoid but not to dinitrophenylated antigens. The abiltty to detect specificity and cross-reactivity of cellular immune reaction has broad implications for investigations of cellular immunity as well as many potential applications in the diagnosis and understanding the patogenesis of inflammatory and neoplastic diseases in which cellular immune discrimination may be involved.

  12. Characterization of HIV-1 Gag-specific T cell responses in chronically infected Indian population

    Science.gov (United States)

    Kaushik, S; Vajpayee, M; Wig, N; Seth, P

    2005-01-01

    India is at the epicentre of the global HIV/AIDS epidemic in South-east Asia, predominated by subtype C infections. It is important to characterize HIV-1-specific T cell responses in this particular population with the aim of identifying protective correlates of immunity to control HIV-1 infection. In this study, we performed a comprehensive analysis of the breadth and magnitude of T cell responses directed at HIV-1 subtype C Gag, one of the most conserved HIV-1 proteins. The study population consisted of antiretroviral naive, chronic HIV-1 subtype C-infected individuals at various stages of infection. We used recent advanced techniques such as enzyme-linked immunospot (ELISPOT) assay and intracellular cytokine staining to quantify the total CD4+ and CD8+ T cell response to HIV-1 gag at single peptide level, regardless of HLA haplotype of the infected individual. The p24-Gag was identified as the most frequently recognized subunit protein with the greatest magnitude of CD4+ and CD8+ T cell responses. Stronger and broader CD8 T cell responses were recognized, contrasting with the weaker and narrower CD4 T cell responses with regard to Gag protein subunits. The magnitude of the HIV-specific interferon (IFN)-γ responses was observed to be higher than the corresponding interleukin (IL)-2 response, indicating the persistence of antigenic load in chronically infected Indian population due to the probable dysfunction of HIV-specific, IFN-γ-secreting CD8 T cells in absence of IL-2 help. PMID:16232229

  13. Retrovolution: HIV-driven evolution of cellular genes and improvement of anticancer drug activation.

    Science.gov (United States)

    Rossolillo, Paola; Winter, Flore; Simon-Loriere, Etienne; Gallois-Montbrun, Sarah; Negroni, Matteo

    2012-08-01

    In evolution strategies aimed at isolating molecules with new functions, screening for the desired phenotype is generally performed in vitro or in bacteria. When the final goal of the strategy is the modification of the human cell, the mutants selected with these preliminary screenings may fail to confer the desired phenotype, due to the complex networks that regulate gene expression in higher eukaryotes. We developed a system where, by mimicking successive infection cycles with HIV-1 derived vectors containing the gene target of the evolution in their genome, libraries of gene mutants are generated in the human cell, where they can be directly screened. As a proof of concept we created a library of mutants of the human deoxycytidine kinase (dCK) gene, involved in the activation of nucleoside analogues used in cancer treatment, with the aim of isolating a variant sensitizing cancer cells to the chemotherapy compound Gemcitabine, to be used in gene therapy for anti-cancer approaches or as a poorly immunogenic negative selection marker for cell transplantation approaches. We describe the isolation of a dCK mutant, G12, inducing a 300-fold sensitization to Gemcitabine in cells originally resistant to the prodrug (Messa 10K), an effect 60 times stronger than the one induced by the wt enzyme. The phenotype is observed in different tumour cell lines irrespective of the insertion site of the transgene and is due to a change in specificity of the mutated kinase in favour of the nucleoside analogue. The mutations characterizing G12 are distant from the active site of the enzyme and are unpredictable on a rational basis, fully validating the pragmatic approach followed. Besides the potential interest of the G12 dCK variant for therapeutic purposes, the methodology developed is of interest for a large panel of applications in biotechnology and basic research.

  14. Retrovolution: HIV-driven evolution of cellular genes and improvement of anticancer drug activation.

    Directory of Open Access Journals (Sweden)

    Paola Rossolillo

    2012-08-01

    Full Text Available In evolution strategies aimed at isolating molecules with new functions, screening for the desired phenotype is generally performed in vitro or in bacteria. When the final goal of the strategy is the modification of the human cell, the mutants selected with these preliminary screenings may fail to confer the desired phenotype, due to the complex networks that regulate gene expression in higher eukaryotes. We developed a system where, by mimicking successive infection cycles with HIV-1 derived vectors containing the gene target of the evolution in their genome, libraries of gene mutants are generated in the human cell, where they can be directly screened. As a proof of concept we created a library of mutants of the human deoxycytidine kinase (dCK gene, involved in the activation of nucleoside analogues used in cancer treatment, with the aim of isolating a variant sensitizing cancer cells to the chemotherapy compound Gemcitabine, to be used in gene therapy for anti-cancer approaches or as a poorly immunogenic negative selection marker for cell transplantation approaches. We describe the isolation of a dCK mutant, G12, inducing a 300-fold sensitization to Gemcitabine in cells originally resistant to the prodrug (Messa 10K, an effect 60 times stronger than the one induced by the wt enzyme. The phenotype is observed in different tumour cell lines irrespective of the insertion site of the transgene and is due to a change in specificity of the mutated kinase in favour of the nucleoside analogue. The mutations characterizing G12 are distant from the active site of the enzyme and are unpredictable on a rational basis, fully validating the pragmatic approach followed. Besides the potential interest of the G12 dCK variant for therapeutic purposes, the methodology developed is of interest for a large panel of applications in biotechnology and basic research.

  15. Rapid, Quantitative Mapping of Anti-HIV Type 1 Envelope Serum Antibody Specificities

    OpenAIRE

    Powell, Rebecca L.R.; Lindsay, Ross W.B.; Wilson, Aaron; Carpov, Alexei; Rabinovich, Svetlana; Hoffenberg, Simon; Caulfield, Michael J.

    2013-01-01

    A new generation of extremely broad and potent neutralizing antibodies (bNAbs) has been isolated from HIV-infected subjects. This has refocused interest in the sites of vulnerability targeted by these bNAbs and in the potential for designing Envelope (Env) immunogens that display these sites. Standard methods for evaluating HIV-1 vaccine candidates do not enable epitope mapping on the HIV Env spike, the target for NAbs. To meet the need for rapid analysis of Ab specificity, we designed a mult...

  16. Negative modulation of suppressive HIV-specific regulatory T cells by IL-2 adjuvanted therapeutic vaccine.

    Science.gov (United States)

    Brezar, Vedran; Hani, Lylia; Surenaud, Mathieu; Hubert, Audrey; Lacabaratz, Christine; Lelièvre, Jean-Daniel; Levy, Yves; Seddiki, Nabila

    2017-07-01

    The potential benefit in using IL-2 in immunotherapy for cancer and autoimmunity has been linked to the modulation of immune responses, which partly relies on a direct effect on Tregs populations. Here, we revisited the role of IL-2 in HIV infection and investigated whether its use as an adjuvant with therapeutic vaccination, impacts on HIV-specific responses. Antiretroviral therapy treated-patients were randomized to receive 4 boosts of vaccination (ALVACHIV/Lipo-6T, weeks 0/4/8/12) followed by 3 cycles of IL-2 (weeks 16/24/32) before treatment interruption (TI) at week40. IL-2 administration increased significantly HIV-specific CD4+CD25+CD134+ T-cell responses, which inversely correlated with viral load after TI (r = -0.7, p increased global CD25+CD127lowFoxP3+Tregs (p Tregs (p Tregs were inversely correlated with IFN-γ producing specific-effectors (p = 0.03) and positively correlated with viral load (r = 0.7, p = 0.01), revealing their undesired presence during chronic infection. Global Tregs, but not HIV-specific Tregs, inversely correlated with a decrease in exhausted PD1+CD95+ T-cells (p = 0.001). Altogether, our results underline the negative impact of HIV-specific Tregs on HIV-specific effectors and reveal the beneficial use of IL-2 as an adjuvant as its administration increases global Tregs that impact on T-cell exhaustion and decreases HIV-specific CD39+Tregs by shifting the balance towards effectors.

  17. Recent Progress toward Engineering HIV-1-Specific Neutralizing Monoclonal Antibodies

    OpenAIRE

    Ming Sun; Yue Li; Huiwen Zheng; Yiming Shao

    2016-01-01

    The recent discoveries of broadly potent neutralizing human monoclonal antibodies represent a new generation of antiretrovirals for the treatment and prophylaxis. Antibodies are generally considered more effective and safer and have been proved to provide passive protection against mucosal challenge in humanized mice and macaques. Several neutralizing Abs could protect animals against HIV-1 but are not effective when used in an established infected model for therapy. In order to overcome the ...

  18. A Review of HIV-Specific Patient-Reported Outcome Measures.

    Science.gov (United States)

    Engler, Kim; Lessard, David; Lebouché, Bertrand

    2016-09-16

    The use of patient-reported outcome (PRO) measures to provide added feedback to health providers is receiving interest as a means of improving clinical care and patient outcomes, and contributing to more patient-centered care. In human immunodeficiency virus (HIV), while PROs are used in research, their application in clinical practice has been limited despite their potential utility. PRO selection is an important consideration when contemplating their use. As past reviews of PROs in HIV have focused on particular areas (e.g. disability, satisfaction with care), a more comprehensive review could better inform on the available instruments and their scope. This article reviews HIV-specific PROs to produce an inventory and to identify the central concepts targeted over time. Seven databases were searched (HAPI, MEDLINE, PsychINFO, PubMed, EMBASE, CINAHL, Google Scholar), generating 14,794 records for evaluation. From these records, 117 HIV-specific PROs were identified and categorized based on a content analysis of their targeted concept: Health-Related Quality of Life (23; 20 %), ART and Adherence-Related Views and Experiences (19; 16 %), Healthcare-Related Views and Experiences (15; 13 %), Psychological Challenges (12; 10 %), Symptoms (12; 10 %), Psychological Resources (10; 9 %), HIV Self-Management and Self-Care (8; 7 %), HIV-Related Stigma (8; 7 %), Body and Facial Appearance (4; 3 %), Social Support (3; 3 %), Sexual and Reproductive Health (2; 2 %), and Disability (1; 1 %). This review highlights the variety and evolution of HIV-specific PROs, with the arrival of seven categories of PROs only after the advent of highly-active antiretroviral therapy. Our inventory also offers a useful resource. However, the interest of further HIV-specific PRO development should be explored in sexual health, which received little independent attention.

  19. Changes in cellular immune activation and memory T-cell subsets in HIV-infected Zambian children receiving HAART.

    Science.gov (United States)

    Rainwater-Lovett, Kaitlin; Nkamba, Hope; Mubiana-Mbewe, Mwangelwa; Moore, Carolyn B; Margolick, Joseph; Moss, William J

    2014-12-15

    Increased exposure to a broad array of pathogens in children residing in sub-Saharan Africa may lead to heightened immune activation and increased proportions of memory T cells. Changes in the size of these cellular subsets have implications for restoration of normal immune function after treatment with highly active antiretroviral therapy (HAART) and are not well characterized in young sub-Saharan African children. CD4⁺ and CD8⁺ T-cell subsets were measured by flow cytometry in 157 HIV-infected Zambian children before and at 3-month intervals during HAART for up to 30 months and in 34 control children at a single study visit. Before HAART, HIV-infected children had higher levels of activated and effector memory (EM) CD4⁺ and CD8⁺ T cells, and lower levels of naive T cells and CD8⁺ T cells expressing IL-7Rα, compared with control children. The median duration of follow-up was 14.9 months (interquartile range, 6.4-23.2) among 120 HIV-infected children with at least 1 study follow-up visit. Levels of immune activation and EM CD4⁺ T cells declined within 6 months of HAART, but the percentages of EM CD4 T cells and effector CD8⁺ T cells remained elevated through 30 months of HAART. IL-7Rα-expressing CD8⁺ T cells increased with HAART, suggesting expansion of memory capacity. HAART significantly reduced levels of immune activation and EM CD4⁺ T cells, and promoted reconstitution of naive T cells and IL-7Rα-expressing CD8⁺ T cells. However, persistently high levels of EM CD4⁺ T cells in HIV-infected children may reflect chronic perturbations in T-cell subset composition.

  20. Envelope-specific antibodies and antibody-derived molecules for treating and curing HIV infection

    Science.gov (United States)

    Ferrari, Guido; Haynes, Barton F.; Koenig, Scott; Nordstrom, Jeffrey L.; Margolis, David M.; Tomaras, Georgia D.

    2017-01-01

    HIV-1 is a retrovirus that integrates into host chromatin and can remain transcriptionally quiescent in a pool of immune cells. This characteristic enables HIV-1 to evade both host immune responses and antiretroviral drugs, leading to persistent infection. Upon reactivation of proviral gene expression, HIV-1 envelope (HIV-1 Env) glycoproteins are expressed on the cell surface, transforming latently infected cells into targets for HIV-1 Env-specific monoclonal antibodies (mAbs), which can engage immune effector cells to kill productively infected CD4+ T cells and thus limit the spread of progeny virus. Recent innovations in antibody engineering have resulted in novel immunotherapeutics such as bispecific dual-affinity re-targeting (DART) molecules and other bi- and trispecific antibody designs that can recognize HIV-1 Env and recruit cytotoxic effector cells to kill CD4+ T cells latently infected with HIV‑1. Here, we review these immunotherapies, which are designed with the goal of curing HIV-1 infection. PMID:27725635

  1. GIM3E: Condition-specific Models of Cellular Metabolism Developed from Metabolomics and Expression Data

    Energy Technology Data Exchange (ETDEWEB)

    Schmidt, Brian; Ebrahim, Ali; Metz, Thomas O.; Adkins, Joshua N.; Palsson, Bernard O.; Hyduke, Daniel R.

    2013-11-15

    Motivation: Genome-scale metabolic models have been used extensively to investigate alterations in cellular metabolism. The accuracy of these models to represent cellular metabolism in specific conditions has been improved by constraining the model with omics data sources. However, few practical methods for integrating metabolomics data with other omics data sources into genome-scale models of metabolism have been reported. Results: GIMMME (Gene Inactivation Moderated by Metabolism, Metabolomics, and Expression) is an algorithm that enables the development of condition-specific models based on an objective function, transcriptomics, and intracellular metabolomics data. GIMMME establishes metabolite utilization requirements with metabolomics data, uses model-paired transcriptomics data to find experimentally supported solutions, and also provides calculations of the turnover (production / consumption) flux of metabolites. GIMMME was employed to investigate the effects of integrating additional omics datasets to create increasingly constrained solution spaces of Salmonella Typhimurium metabolism during growth in both rich and virulence media. This integration proved to be informative and resulted in a requirement of additional active reactions (12 in each case) or metabolites (26 or 29, respectively). The addition of constraints from transcriptomics also impacted the allowed solution space, and the cellular metabolites with turnover fluxes that were necessarily altered by the change in conditions increased from 118 to 271 of 1397. Availability: GIMMME has been implemented in Python and requires a COBRApy 0.2.x. The algorithm and sample data described here are freely available at: http://opencobra.sourceforge.net/

  2. The colocalization potential of HIV-specific CD8+ and CD4+ T-cells is mediated by integrin β7 but not CCR6 and regulated by retinoic acid.

    Science.gov (United States)

    Wacleche, Vanessa Sue; Chomont, Nicolas; Gosselin, Annie; Monteiro, Patricia; Goupil, Mathieu; Kared, Hassen; Tremblay, Cécile; Bernard, Nicole; Boulassel, Mohamed-Rachid; Routy, Jean-Pierre; Ancuta, Petronela

    2012-01-01

    CD4(+) T-cells from gut-associated lymphoid tissues (GALT) are major targets for HIV-1 infection. Recruitment of excess effector CD8(+) T-cells in the proximity of target cells is critical for the control of viral replication. Here, we investigated the colocalization potential of HIV-specific CD8(+) and CD4(+) T-cells into the GALT and explored the role of retinoic acid (RA) in regulating this process in a cohort of HIV-infected subjects with slow disease progression. The expression of the gut-homing molecules integrin β7, CCR6, and CXCR3 was identified as a "signature" for HIV-specific but not CMV-specific CD4(+) T-cells thus providing a new explanation for their enhanced permissiveness to infection in vivo. HIV-specific CD8(+) T-cells also expressed high levels of integrin β7 and CXCR3; however CCR6 was detected at superior levels on HIV-specific CD4(+) versus CD8(+) T-cells. All trans RA (ATRA) upregulated the expression of integrin β7 but not CCR6 on HIV-specific T-cells. Together, these results suggest that HIV-specific CD8(+) T-cells may colocalize in excess with CD4(+) T-cells into the GALT via integrin β7 and CXCR3, but not via CCR6. Considering our previous findings that CCR6(+)CD4(+) T-cells are major cellular targets for HIV-DNA integration in vivo, a limited ability of CD8(+) T-cells to migrate in the vicinity of CCR6(+)CD4(+) T-cells may facilitate HIV replication and dissemination at mucosal sites.

  3. The colocalization potential of HIV-specific CD8+ and CD4+ T-cells is mediated by integrin β7 but not CCR6 and regulated by retinoic acid.

    Directory of Open Access Journals (Sweden)

    Vanessa Sue Wacleche

    Full Text Available CD4(+ T-cells from gut-associated lymphoid tissues (GALT are major targets for HIV-1 infection. Recruitment of excess effector CD8(+ T-cells in the proximity of target cells is critical for the control of viral replication. Here, we investigated the colocalization potential of HIV-specific CD8(+ and CD4(+ T-cells into the GALT and explored the role of retinoic acid (RA in regulating this process in a cohort of HIV-infected subjects with slow disease progression. The expression of the gut-homing molecules integrin β7, CCR6, and CXCR3 was identified as a "signature" for HIV-specific but not CMV-specific CD4(+ T-cells thus providing a new explanation for their enhanced permissiveness to infection in vivo. HIV-specific CD8(+ T-cells also expressed high levels of integrin β7 and CXCR3; however CCR6 was detected at superior levels on HIV-specific CD4(+ versus CD8(+ T-cells. All trans RA (ATRA upregulated the expression of integrin β7 but not CCR6 on HIV-specific T-cells. Together, these results suggest that HIV-specific CD8(+ T-cells may colocalize in excess with CD4(+ T-cells into the GALT via integrin β7 and CXCR3, but not via CCR6. Considering our previous findings that CCR6(+CD4(+ T-cells are major cellular targets for HIV-DNA integration in vivo, a limited ability of CD8(+ T-cells to migrate in the vicinity of CCR6(+CD4(+ T-cells may facilitate HIV replication and dissemination at mucosal sites.

  4. Immune responses in human infections with Brugia malayi: specific cellular unresponsiveness to filarial antigens.

    Science.gov (United States)

    Piessens, W F; McGreevy, P B; Piessens, P W; McGreevy, M; Koiman, I; Saroso, J S; Dennis, D T

    1980-01-01

    We evaluated the cellular immune competence of 101 subjects living in an area of South Kalimantan (Borneo) where Malayan filariasis is endemic. All patients with elephantiasis but none with other clinical stages of filariasis reacted with adult worm antigens. The majority of subjects without clinical or parasitological evidence of filariasis and approximately one-half of those with amicrofilaremic filariasis reacted with microfilarial antigens. In contrast, most patients with patent microfilaremia did not respond to microfilarial antigens. The in vitro reactivity of all patient categories to nonparasite antigens was similar to that of the distant control group. These results indicate that patent microfilaremia is associated with a state of specific cellular immune unresponsiveness and are consistent with the current hypothesis that the various clinical manifestations of filariasis result from different types of immune responses to distinct antigens associated with different developmental stages of filarial worms. PMID:7350196

  5. The binding of NCAM to FGFR1 induces a specific cellular response mediated by receptor trafficking

    DEFF Research Database (Denmark)

    Francavilla, Chiara; Cattaneo, Paola; Berezin, Vladimir

    2009-01-01

    different from that elicited by FGF-2. In contrast to FGF-induced degradation of endocytic FGFR1, NCAM promotes the stabilization of the receptor, which is recycled to the cell surface in a Rab11- and Src-dependent manner. In turn, FGFR1 recycling is required for NCAM-induced sustained activation of various...... effectors. Furthermore, NCAM, but not FGF-2, promotes cell migration, and this response depends on FGFR1 recycling and sustained Src activation. Our results implicate NCAM as a nonconventional ligand for FGFR1 that exerts a peculiar control on the intracellular trafficking of the receptor, resulting...... in a specific cellular response. Besides introducing a further level of complexity in the regulation of FGFR1 function, our findings highlight the link of FGFR recycling with sustained signaling and cell migration and the critical role of these events in dictating the cellular response evoked by receptor...

  6. A candidate DNA vaccine elicits HCV specific humoral and cellular immune responses

    Institute of Scientific and Technical Information of China (English)

    Li-Xin Zhu; Jing Liu; Ye Ye; You-Hua Xie; Yu-Ying Kong; Guang-Di Li; Yuan Wang

    2004-01-01

    AIM: To investigate the immunogenicity of candidate DNA vaccine against hepatitis C virus (HCV) delivered by two plasmids expressing HCV envelope protein 1 (E1) and envelope protein 2 (E2) antigens respectively and to study the effect of CpG adjuvant on this candidate vaccine.METHODS: Recombinant plasmids expressing HCV E1 and E2 antigens respectively were used to simultaneously inoculate mice with or without CpG adjuvant. Antisera were then collected and titers of anti-HCV antibodies were analyzed by ELISA. One month after the last injection, animals were sacrificed to prepare single-cell suspension of splenocytes.These cells were subjected to HCVantigen specific proliferation assays and cytokine secretion assays to evaluate the cellular immune responses of the vaccinated animals.RESULTS: Antibody responses to HCV E1 and E2 antigens were detected in vaccinated animals. Animals receiving CpG adjuvant had slightly lower titers of anti-HCV antibodies in the sera, while the splenocytes from these animals showed higher HCV-antigen specific proliferation. Analysis of cytokine secretion from the splenocytes was consistent with the above results. While no antigen-specific IL-4 secretion was detected for all vaccinated animals, HCV antigen-specific INF-γ secretion was detected for the splenocytes of vaccinated animals. CpG adjuvant enhanced the secretion of INF-γ but did not change the profile of IL-4 secretion.CONCLUSION: Vaccination of mice with plasmids encoding HCV E1 and E2 antigens induces humoral and cellular immune responses. CpG adjuvant significantly enhances the cellular immune response.

  7. Sequential Dysfunction and Progressive Depletion of Candida albicans-Specific CD4 T Cell Response in HIV-1 Infection.

    Directory of Open Access Journals (Sweden)

    Fengliang Liu

    2016-06-01

    Full Text Available Loss of immune control over opportunistic infections can occur at different stages of HIV-1 (HIV disease, among which mucosal candidiasis caused by the fungal pathogen Candida albicans (C. albicans is one of the early and common manifestations in HIV-infected human subjects. The underlying immunological basis is not well defined. We have previously shown that compared to cytomegalovirus (CMV-specific CD4 cells, C. albicans-specific CD4 T cells are highly permissive to HIV in vitro. Here, based on an antiretroviral treatment (ART naïve HIV infection cohort (RV21, we investigated longitudinally the impact of HIV on C. albicans- and CMV-specific CD4 T-cell immunity in vivo. We found a sequential dysfunction and preferential depletion for C. albicans-specific CD4 T cell response during progressive HIV infection. Compared to Th1 (IFN-γ, MIP-1β functional subsets, the Th17 functional subsets (IL-17, IL-22 of C. albicans-specific CD4 T cells were more permissive to HIV in vitro and impaired earlier in HIV-infected subjects. Infection history analysis showed that C. albicans-specific CD4 T cells were more susceptible to HIV in vivo, harboring modestly but significantly higher levels of HIV DNA, than CMV-specific CD4 T cells. Longitudinal analysis of HIV-infected individuals with ongoing CD4 depletion demonstrated that C. albicans-specific CD4 T-cell response was preferentially and progressively depleted. Taken together, these data suggest a potential mechanism for earlier loss of immune control over mucosal candidiasis in HIV-infected patients and provide new insights into pathogen-specific immune failure in AIDS pathogenesis.

  8. Humans with chimpanzee-like major histocompatibility complex-specificities control HIV-1 infection

    DEFF Research Database (Denmark)

    Hoof, Ilka; Kesmir, Can; Lund, Ole;

    2008-01-01

    Background: Major histocompatibility complex (MHC) class I molecules allow immune surveillance by presenting a snapshot of the intracellular state of a cell to circulating cytotoxic T lymphocytes. The MHC class I alleles of an HIV-1 infected individual strongly influence the level of viremia...... and the progression rate to AIDS. Chimpanzees control HIV-1 viral replication and develop a chronic infection without progressing to AIDS. A similar course of disease is observed in human long-term non-progressors. Objective: To investigate if long-term non-progressors and chimpanzees have functional similarities...... in their MHC class I repertoire. Methods: We compared the specificity of groups of human MHC molecules associated with different levels of viremia in HIV-1 infected individuals with those of chimpanzee. Results and conclusion: We demonstrate that human MHC with control of HIV-1 viral load share binding motifs...

  9. Are Clade Specific HIV Vaccines a Necessity? An Analysis Based on Mathematical Models

    Directory of Open Access Journals (Sweden)

    Dobromir Dimitrov

    2015-12-01

    Full Text Available As HIV-1 envelope immune responses are critical to vaccine related protection, most candidate HIV vaccines entering efficacy trials are based upon a clade specific design. This need for clade specific vaccine prototypes markedly reduces the implementation of potentially effective HIV vaccines. We utilized a mathematical model to determine the effectiveness of immediate roll-out of a non-clade matched vaccine with reduced efficacy compared to constructing clade specific vaccines, which would take considerable time to manufacture and test in safety and efficacy trials. We simulated the HIV epidemic in San Francisco (SF and South Africa (SA and projected effectiveness of three vaccination strategies: i immediate intervention with a 20–40% vaccine efficacy (VE non-matched vaccine, ii delayed intervention by developing a 50% VE clade-specific vaccine, and iii immediate intervention with a non-matched vaccine replaced by a clade-specific vaccine when developed. Immediate vaccination with a non-clade matched vaccine, even with reduced efficacy, would prevent thousands of new infections in SF and millions in SA over 30 years. Vaccination with 50% VE delayed for five years needs six and 12 years in SA to break-even with immediate 20 and 30% VE vaccination, respectively, while not able to surpass the impact of immediate 40% VE vaccination over 30 years. Replacing a 30% VE with a 50% VE vaccine after 5 years reduces the HIV acquisition by 5% compared to delayed vaccination. The immediate use of an HIV vaccine with reduced VE in high risk communities appears desirable over a short time line but higher VE should be the pursued to achieve strong long-term impact. Our analysis illustrates the importance of developing surrogate markers (correlates of protection to allow bridging types of immunogenicity studies to support more rapid assessment of clade specific vaccines.

  10. Distinct roles of specific fatty acids in cellular processes: implications for interpreting and reporting experiments

    OpenAIRE

    Watt, Matthew J.; Hoy, Andrew J.; Muoio, Deborah M.; Coleman, Rosalind A.

    2011-01-01

    Plasma contains a variety of long-chain fatty acids (FAs), such that about 35% are saturated and 65% are unsaturated. There are countless examples that show how different FAs impart specific and unique effects, or even opposing actions, on cellular function. Despite these differing effects, palmitate (C16:0) is regularly used to represent “FAs” in cell based experiments. Although palmitate can be useful to induce and study stress effects in cultured cells, these effects in isolation are not p...

  11. In situ amplification of DNA fragments specific for human Y chromosome in cellular nuclei by PCR

    Institute of Scientific and Technical Information of China (English)

    张锡元; 姜海波; 李立家; 马琦; 杨建琪; 刘汀

    1996-01-01

    Using single primer pairs Y3 and Y4, in siru polymerase chain reaction (in situ PCR) was successfully performed on the specimen slides of peripheral leukocytes. By both of the direct digpxiginin-11-dUTP incorporation into PCR products with in situ PCR (direct in situ PCR) and in situ PCR followed by detection of in situ hybridization (indirect in siru PCR), DNA fragments specific for human Y chromosome were obviously amplified in cellular nuclei of specimens on the slides. The results were verified by Southern analysis. The methodology of in situ PCR and its application were discussed.

  12. Long-term nonprogression and broad HIV-1-specific proliferative T-cell responses

    Directory of Open Access Journals (Sweden)

    Nesrina eImami

    2013-03-01

    Full Text Available Complex mechanisms underlying the maintenance of fully functional, proliferative, HIV-1-specific T-cell responses involve processes from early T-cell development through to the final stages of T-cell differentiation and antigen recognition. Virus-specific proliferative CD4 and CD8 T-cell responses, important for the control of infection, are observed in some HIV-1+ patients during early stages of disease, and are maintained in long-term nonprogressing subjects. In the vast majority of HIV-1+ patients, full immune functionality is lost when proliferative HIV-1-specific T-cell responses undergo a variable progressive decline throughout the course of chronic infection. This appears irreparable despite administration of potent combination antiretroviral therapy, which to date is non-curative, necessitating life-long administration and the development of effective, novel, therapeutic interventions. While a sterilising cure, involving clearance of virus from the host, remains a primary aim, a functional cure may be a more feasible goal with considerable impact on worldwide HIV-1 infection. Such an approach would enable long-term co-existence of host and virus in the absence of toxic and costly drugs. Effective immune homeostasis coupled with a balanced response appropriately targeting conserved viral antigens, in a manner that avoids hyperactivation and exhaustion, may prove to be the strongest correlate of durable viral control. This review describes novel concepts underlying full immune functionality in the context of HIV-1 infection, which may be utilised in future strategies designed to improve upon existing therapy. The aim will be to induce long-term nonprogressor or elite controller status in every infected host, through immune-mediated control of viraemia and reduction of viral reservoirs, leading to lower HIV-1 transmission rates.

  13. DNA encoding an HIV-1 Gag/human lysosome-associated membrane protein-1 chimera elicits a broad cellular and humoral immune response in Rhesus macaques.

    Directory of Open Access Journals (Sweden)

    Priya Chikhlikar

    Full Text Available Previous studies of HIV-1 p55Gag immunization of mice have demonstrated the usefulness of targeting antigens to the cellular compartment containing the major histocompatibility complex type II (MHC II complex molecules by use of a DNA antigen formulation encoding Gag as a chimera with the mouse lysosome-associated membrane protein (mLAMP/gag. In the present study, we have analyzed the magnitude and breadth of Gag-specific T-lymphocyte and antibody responses elicited in Rhesus macaques after immunization with DNA encoding a human LAMP/gag (hLAMP/gag chimera. ELISPOT analyses indicated that the average Gag-specific IFN-gamma response elicited by the hLAMP/gag chimera was detectable after only two or three naked DNA immunizations in all five immunized macaques and reached an average of 1000 spot-forming cells (SFC/10(6 PBMCs. High IFN-gamma ELISPOT responses were detected in CD8(+-depleted cells, indicating that CD4(+ T-cells play a major role in these responses. The T-cell responses of four of the macaques were also tested by use of ELISPOT to 12 overlapping 15-amino acids (aa peptide pools containing ten peptides each, encompassing the complete Gag protein sequence. The two Mamu 08 immunized macaques responded to eight and twelve of the pools, the Mamu B01 to six, and the other macaque to five pools indicating that the hLAMP/gag DNA antigen formulation elicits a broad T-cell response against Gag. Additionally, there was a strong HIV-1-specific IgG response. The IgG antibody titers increased after each DNA injection, indicating a strong amnestic B-cell response, and were highly elevated in all the macaques after three immunizations. Moreover, the serum of each macaque recognized 13 of the 49 peptides of a 20-aa peptide library covering the complete Gag amino acid sequence. In addition, HIV-1-specific IgA antibodies were present in the plasma and external secretions, including nasal washes. These data support the findings of increased

  14. Non-specific cellular uptake of surface-functionalized quantum dots

    CERN Document Server

    Kelf, T A; Sun, J; Kim, E J; Goldys, E M; Zvyagin, A V; 10.1088/0957-4484/21/28/285105

    2010-01-01

    We report a systematic empirical study of nanoparticle internalization into cells via non-specific pathways. The nanoparticles were comprised of commercial quantum dots (QDs) that were highly visible under a fluorescence confocal microscope. Surface-modified QDs with basic biologically-significant moieties, e.g. carboxyl, amino, streptavidin were used, in combination with the surface derivatization with polyethylene glycol (PEG) in a range of immortalized cell lines. Internalization rates were derived from image analysis and a detailed discussion about the effect of nanoparticle size, charge and surface groups is presented. We find that PEG-derivatization dramatically suppresses the non-specific uptake while PEG-free carboxyl and amine functional groups promote QD internalization. These uptake variations displayed a remarkable consistency across different cell types. The reported results are important for experiments concerned with cellular uptake of surface-functionalized nanomaterials, both when non-specifi...

  15. Ultrastructural studies of time-course and cellular specificity of interleukin-1 mediated islet cytotoxicity

    DEFF Research Database (Denmark)

    Mandrup-Poulsen, T; Egeberg, J; Nerup, J

    1987-01-01

    of incubation and examined by electron microscopy in a blinded fashion. Already after 30 min, accumulation of opaque intracytoplasmic bodies without apparent surrounding membranes, and autophagic vacuoles were seen in about 20% of the beta cells examined in rat islets exposed to interleukin-1. After 16 h......Previous electron-microscopic studies of isolated islets of Langerhans exposed to the monokine interleukin-1 for 7 days have indicated that interleukin-1 is cytotoxic to all islet cells. To study the time-course and possible cellular specificity of interleukin-1 cytotoxicity to islets exposed...... of incubation with interleukin-1, more than 80% of rat beta cells showed signs of degeneration. Beta cell specific changes similar to those observed in rat islets exposed to IL-1 for 30 min were seen in human islets exposed to IL-1 for 24 h. The described changes were not observed in alpha cells in interleukin...

  16. Cell-type specific requirements for thiol/disulfide exchange during HIV-1 entry and infection.

    Science.gov (United States)

    Stantchev, Tzanko S; Paciga, Mark; Lankford, Carla R; Schwartzkopff, Franziska; Broder, Christopher C; Clouse, Kathleen A

    2012-12-03

    The role of disulfide bond remodeling in HIV-1 infection is well described, but the process still remains incompletely characterized. At present, the data have been predominantly obtained using established cell lines and/or CXCR4-tropic laboratory-adapted virus strains. There is also ambiguity about which disulfide isomerases/reductases play a major role in HIV-1 entry, as protein disulfide isomerase (PDI) and/or thioredoxin (Trx) have emerged as the two enzymes most often implicated in this process. We have extended our previous findings and those of others by focusing on CCR5-using HIV-1 strains and their natural targets--primary human macrophages and CD4+ T lymphocytes. We found that the nonspecific thiol/disulfide exchange inhibitor, 5,5'-dithiobis(2-nitrobenzoic acid) (DTNB), significantly reduced HIV-1 entry and infection in cell lines, human monocyte-derived macrophages (MDM), and also phytohemagglutinin (PHA)-stimulated peripheral blood mononuclear cells (PBMC). Subsequent studies were performed using specific anti-PDI or Trx monoclonal antibodies (mAb) in HIV-1 envelope pseudotyped and wild type (wt) virus infection systems. Although human donor-to-donor variability was observed as expected, Trx appeared to play a greater role than PDI in HIV-1 infection of MDM. In contrast, PDI, but not Trx, was predominantly involved in HIV-1 entry and infection of the CD4+/CCR5+ T cell line, PM-1, and PHA-stimulated primary human T lymphocytes. Intriguingly, both PDI and Trx were present on the surface of MDM, PM-1 and PHA-stimulated CD4+ T cells. However, considerably lower levels of Trx were detected on freshly isolated CD4+ lymphocytes, compared to PHA-stimulated cells. Our findings clearly demonstrate the role of thiol/disulfide exchange in HIV-1 entry in primary T lymphocytes and MDM. They also establish a cell-type specificity regarding the involvement of particular disulfide isomerases/reductases in this process and may provide an explanation for differences

  17. Cell-type specific requirements for thiol/disulfide exchange during HIV-1 entry and infection

    Directory of Open Access Journals (Sweden)

    Stantchev Tzanko S

    2012-12-01

    Full Text Available Abstract Background The role of disulfide bond remodeling in HIV-1 infection is well described, but the process still remains incompletely characterized. At present, the data have been predominantly obtained using established cell lines and/or CXCR4-tropic laboratory-adapted virus strains. There is also ambiguity about which disulfide isomerases/ reductases play a major role in HIV-1 entry, as protein disulfide isomerase (PDI and/or thioredoxin (Trx have emerged as the two enzymes most often implicated in this process. Results We have extended our previous findings and those of others by focusing on CCR5-using HIV-1 strains and their natural targets - primary human macrophages and CD4+ T lymphocytes. We found that the nonspecific thiol/disulfide exchange inhibitor, 5,5'-dithiobis(2-nitrobenzoic acid (DTNB, significantly reduced HIV-1 entry and infection in cell lines, human monocyte-derived macrophages (MDM, and also phytohemagglutinin (PHA-stimulated peripheral blood mononuclear cells (PBMC. Subsequent studies were performed using specific anti-PDI or Trx monoclonal antibodies (mAb in HIV-1 envelope pseudotyped and wild type (wt virus infection systems. Although human donor-to-donor variability was observed as expected, Trx appeared to play a greater role than PDI in HIV-1 infection of MDM. In contrast, PDI, but not Trx, was predominantly involved in HIV-1 entry and infection of the CD4+/CCR5+ T cell line, PM-1, and PHA-stimulated primary human T lymphocytes. Intriguingly, both PDI and Trx were present on the surface of MDM, PM-1 and PHA-stimulated CD4+ T cells. However, considerably lower levels of Trx were detected on freshly isolated CD4+ lymphocytes, compared to PHA-stimulated cells. Conclusions Our findings clearly demonstrate the role of thiol/disulfide exchange in HIV-1 entry in primary T lymphocytes and MDM. They also establish a cell-type specificity regarding the involvement of particular disulfide isomerases/reductases in this

  18. HIV-1 specific IgA detected in vaginal secretions of HIV uninfected women participating in a microbicide trial in Southern Africa are primarily directed toward gp120 and gp140 specificities.

    Directory of Open Access Journals (Sweden)

    Kelly E Seaton

    Full Text Available BACKGROUND: Many participants in microbicide trials remain uninfected despite ongoing exposure to HIV-1. Determining the emergence and nature of mucosal HIV-specific immune responses in such women is important, since these responses may contribute to protection and could provide insight for the rational design of HIV-1 vaccines. METHODS AND FINDINGS: We first conducted a pilot study to compare three sampling devices (Dacron swabs, flocked nylon swabs and Merocel sponges for detection of HIV-1-specific IgG and IgA antibodies in vaginal secretions. IgG antibodies from HIV-1-positive women reacted broadly across the full panel of eight HIV-1 envelope (Env antigens tested, whereas IgA antibodies only reacted to the gp41 subunit. No Env-reactive antibodies were detected in the HIV-negative women. The three sampling devices yielded equal HIV-1-specific antibody titers, as well as total IgG and IgA concentrations. We then tested vaginal Dacron swabs archived from 57 HIV seronegative women who participated in a microbicide efficacy trial in Southern Africa (HPTN 035. We detected vaginal IgA antibodies directed at HIV-1 Env gp120/gp140 in six of these women, and at gp41 in another three women, but did not detect Env-specific IgG antibodies in any women. CONCLUSION: Vaginal secretions of HIV-1 infected women contained IgG reactivity to a broad range of Env antigens and IgA reactivity to gp41. In contrast, Env-binding antibodies in the vaginal secretions of HIV-1 uninfected women participating in the microbicide trial were restricted to the IgA subtype and were mostly directed at HIV-1 gp120/gp140.

  19. Acquisition of HIV-1 resistance in T lymphocytes using an ACA-specific E. coli mRNA interferase.

    Science.gov (United States)

    Chono, Hideto; Matsumoto, Kazuya; Tsuda, Hiroshi; Saito, Naoki; Lee, Karim; Kim, Sujeong; Shibata, Hiroaki; Ageyama, Naohide; Terao, Keiji; Yasutomi, Yasuhiro; Mineno, Junichi; Kim, Sunyoung; Inouye, Masayori; Kato, Ikunoshin

    2011-01-01

    Transcriptional activation of gene expression directed by the long terminal repeat (LTR) of HIV-1 requires both the transactivation response element (TAR) and Tat protein. HIV-1 mutants lacking a functional tat gene are not able to proliferate. Here we take a genetic approach to suppress HIV-1 replication based on Tat-dependent production of MazF, an ACA-specific endoribonuclease (mRNA interferase) from Escherichia coli. When induced, MazF is known to cause Bak- and NBK-dependent apoptotic cell death in mammalian cells. We first constructed a retroviral vector, in which the mazF (ACA-less) gene was inserted under the control of the HIV-1 LTR, which was then transduced into CD4+ T-lymphoid CEM-SS cells in such a way that, upon HIV-1 infection, the mazF gene is induced to destroy the infecting HIV-1 mRNA, preventing HIV-1 replication. Indeed, when the transduced cells were infected with HIV-1 IIIB, the viral replication was effectively inhibited, as HIV-1 IIIB p24 could not be detected in the culture medium. Consistently, not only cell growth but also the CD4 level was not affected by the infection. These results suggest that the HIV-1-LTR-regulated mazF gene was effectively induced upon HIV-1 IIIB infection, which is sufficient enough to destroy the viral mRNA from the infected HIV-1 IIIB to completely block viral proliferation in the cells, but not to affect normal cell growth. These results indicate that the T cells transduced with the HIV-1-LTR-regulated mazF gene acquire HIV-1 resistance, providing an intriguing potential for the use of the HIV-1-LTR-regulated mazF gene in anti-HIV gene therapy.

  20. Latent tuberculosis in HIV positive, diagnosed by the M. tuberculosis specific interferon-gamma test

    DEFF Research Database (Denmark)

    Brock, Inger; Ruhwald, Morten; Lundgren, Bettina

    2006-01-01

    BACKGROUND: Although tuberculosis (TB) is a minor problem in Denmark, severe and complicated cases occur in HIV positive. Since the new M. tuberculosis specific test for latent TB, the QuantiFERON-TB In-Tube test (QFT-IT) became available the patients in our clinic have been screened...

  1. Latent tuberculosis in HIV positive, diagnosed by the M. tuberculosis specific interferon-gamma test

    DEFF Research Database (Denmark)

    Brock, Inger; Ruhwald, Morten; Lundgren, Bettina

    2006-01-01

    BACKGROUND: Although tuberculosis (TB) is a minor problem in Denmark, severe and complicated cases occur in HIV positive. Since the new M. tuberculosis specific test for latent TB, the QuantiFERON-TB In-Tube test (QFT-IT) became available the patients in our clinic have been screened...

  2. Latent tuberculosis in HIV positive, diagnosed by the M. tuberculosis specific interferon-gamma test

    DEFF Research Database (Denmark)

    Brock, Inger; Ruhwald, Morten; Lundgren, Bettina

    2006-01-01

    Although tuberculosis (TB) is a minor problem in Denmark, severe and complicated cases occur in HIV positive. Since the new M. tuberculosis specific test for latent TB, the QuantiFERON-TB In-Tube test (QFT-IT) became available the patients in our clinic have been screened for the presence of latent...

  3. Nuclear Factor 90, a cellular dsRNA binding protein inhibits the HIV Rev-export function

    Directory of Open Access Journals (Sweden)

    St-Laurent Georges

    2006-11-01

    Full Text Available Abstract Background The HIV Rev protein is known to facilitate export of incompletely spliced and unspliced viral transcripts to the cytoplasm, a necessary step in virus life cycle. The Rev-mediated nucleo-cytoplasmic transport of nascent viral transcripts, dependents on interaction of Rev with the RRE RNA structural element present in the target RNAs. The C-terminal variant of dsRNA-binding nuclear protein 90 (NF90ctv has been shown to markedly attenuate viral replication in stably transduced HIV-1 target cell line. Here we examined a mechanism of interference of viral life cycle involving Rev-NF90ctv interaction. Results Since Rev:RRE complex formations depend on protein:RNA and protein:protein interactions, we investigated whether the expression of NF90ctv might interfere with Rev-mediated export of RRE-containing transcripts. When HeLa cells expressed both NF90ctv and Rev protein, we observed that NF90ctv inhibited the Rev-mediated RNA transport. In particular, three regions of NF90ctv protein are involved in blocking Rev function. Moreover, interaction of NF90ctv with the RRE RNA resulted in the expression of a reporter protein coding sequences linked to the RRE structure. Moreover, Rev influenced the subcellular localization of NF90ctv, and this process is leptomycin B sensitive. Conclusion The dsRNA binding protein, NF90ctv competes with HIV Rev function at two levels, by competitive protein:protein interaction involving Rev binding to specific domains of NF90ctv, as well as by its binding to the RRE-RNA structure. Our results are consistent with a model of Rev-mediated HIV-1 RNA export that envisions Rev-multimerization, a process interrupted by NF90ctv.

  4. Bone marrow plasma cells are a primary source of serum HIV-1-specific antibodies in chronically infected individuals.

    Science.gov (United States)

    Montezuma-Rusca, Jairo M; Moir, Susan; Kardava, Lela; Buckner, Clarisa M; Louie, Aaron; Kim, Leo J Y; Santich, Brian H; Wang, Wei; Fankuchen, Olivia R; Diaz, Gabriella; Daub, Janine R; Rosenzweig, Sergio D; Chun, Tae-Wook; Li, Yuxing; Braylan, Raul C; Calvo, Katherine R; Fauci, Anthony S

    2015-03-15

    Several potent and broadly neutralizing Abs to HIV-1 have been isolated recently from peripheral blood B cells of infected individuals, based on prescreening of Ab activity in the serum. However, little is known regarding the cells that make the Abs that circulate in the blood. Accordingly, we investigated the most likely source, the bone marrow, of chronically HIV-1-infected individuals who were not receiving antiretroviral therapy. Increased frequencies of plasma cells, as well as B cell precursors, namely preB-I and preB-II, and decreased frequencies of mature B cells were observed in bone marrow aspirates of these individuals compared with HIV-negative counterparts. Increased frequencies of bone marrow plasma cells are consistent with known hallmarks of HIV-1 infection, namely hypergammaglobulinemia and increased frequencies of peripheral blood plasmablasts. Levels of HIV-1 envelope (Env)-binding and HIV-1-neutralizing Abs were measured in serum, and corresponding frequencies of Ab-secreting or Env-binding cells were measured in the blood (plasmablasts and memory B cells) and in the bone marrow (plasma cells). A strong correlation was observed between serum HIV-1-specific Abs and Env-specific bone marrow-derived plasma cells, but not circulating plasmablasts or memory B cells. These findings demonstrate that, despite HIV-1-induced phenotypic and functional B cell dysregulation in the peripheral blood and secondary lymphoid tissues, bone marrow plasma cells remain a primary source for circulating HIV-1-specific Abs in HIV-1-infected individuals.

  5. Cellular heterogeneity mediates inherent sensitivity-specificity tradeoff in cancer targeting by synthetic circuits.

    Science.gov (United States)

    Morel, Mathieu; Shtrahman, Roman; Rotter, Varda; Nissim, Lior; Bar-Ziv, Roy H

    2016-07-19

    Synthetic gene circuits are emerging as a versatile means to target cancer with enhanced specificity by combinatorial integration of multiple expression markers. Such circuits must also be tuned to be highly sensitive because escape of even a few cells might be detrimental. However, the error rates of decision-making circuits in light of cellular variability in gene expression have so far remained unexplored. Here, we measure the single-cell response function of a tunable logic AND gate acting on two promoters in heterogeneous cell populations. Our analysis reveals an inherent tradeoff between specificity and sensitivity that is controlled by the AND gate amplification gain and activation threshold. We implement a tumor-mimicking cell-culture model of cancer cells emerging in a background of normal ones, and show that molecular parameters of the synthetic circuits control specificity and sensitivity in a killing assay. This suggests that, beyond the inherent tradeoff, synthetic circuits operating in a heterogeneous environment could be optimized to efficiently target malignant state with minimal loss of specificity.

  6. Cellular HIV-1 DNA levels in patients receiving antiretroviral therapy strongly correlate with therapy initiation timing but not with therapy duration

    Directory of Open Access Journals (Sweden)

    Nishida Yasuharu

    2011-05-01

    Full Text Available Abstract Background Viral reservoir size refers to cellular human immunodeficiency virus-1 (HIV-1 DNA levels in CD4+ T lymphocytes of peripheral blood obtained from patients with plasma HIV-1-RNA levels (viral load, VL maintained below the detection limit by antiretroviral therapy (ART. We measured HIV-1 DNA levels in CD4+ lymphocytes in such patients to investigate their clinical significance. Methods CD4+ T lymphocytes were isolated from the peripheral blood of 61 patients with a VL maintained at less than 50 copies/ml for at least 4 months by ART and total DNA was purified. HIV-1 DNA was quantified by nested PCR to calculate the copy number per 1 million CD4+ lymphocytes (relative amount and the copy number in 1 ml of blood (absolute amount. For statistical analysis, the Spearman rank or Wilcoxon signed-rank test was used, with a significance level of 5%. Results CD4 cell counts at the time of sampling negatively correlated with the relative amount of HIV-1 DNA (median = 33 copies/million CD4+ lymphocytes; interquartile range [IQR] = 7-123 copies/million CD4+ lymphocytes, but were not correlated with the absolute amounts (median = 17 copies/ml; IQR = 5-67 copies/ml. Both absolute and relative amounts of HIV-1 DNA were significantly lower in six patients in whom ART was initiated before positive seroconversion than in 55 patients in whom ART was initiated in the chronic phase, as shown by Western blotting. CD4 cell counts before ART introduction were also negatively correlated with both the relative and absolute amounts of HIV-1 DNA. Only the relative amounts of HIV-1 DNA negatively correlated with the duration of VL maintenance below the detection limit, while the absolute amounts were not significantly correlated with this period. Conclusions The amounts of cellular HIV-1 DNA in patients with VLs maintained below the detection limit by the introduction of ART correlated with the timing of ART initiation but not with the duration of ART. In

  7. Organ, cellular, and subcellular localization of brain-specific anion transporter BSAT1.

    Science.gov (United States)

    Baklaushev, V P; Kardashova, K Sh; Gurina, O I; Yusubaliyeva, G M; Zorkina, Ya A; Chekhonin, V P

    2013-08-01

    Organ, cellular, and subcellular localization of brain-specific anion transporter BSAT1 was studied in rats using antibodies to the extracellular fragment (451-557 a.a). The antibodies were shown to recognize the antigen predominantly localized in the nervous tissue, tumors of glial origin, and primordial ovarian follicles. The absence of BSAT1 immunofluorescence signal in kidney and liver sections and accumulation of (125)I labeled antibodies to BSAT1 in these organs indicate that these antibodies do not cross-react with the most common isoforms of OATP expressed in these organs. Analysis of the cellular localization suggests that in the brain, BSAT1 is localized predominantly in astrocytes, but not in endothelial cells, as was previously reported. Laser scanning confocal microscopy with a set of relevant trackers revealed membrane localization of BSAT1. Taking into account the data on the of localization, we can conclude that antibodies to BSAT1 451-557 can be used for basic research of the transport of thyroxin and prostaglandins across the blood brain barrier and for testing the systems for targeted transport of diagnostic preparations and drugs across the blood brain barrier, e.g. to astroglial tumors.

  8. Interacting factors and cellular localization of SR protein-specific kinase Dsk1

    Energy Technology Data Exchange (ETDEWEB)

    Tang, Zhaohua, E-mail: ztang@jsd.claremont.edu [W.M. Keck Science Center, The Claremont Colleges, Claremont, CA 91711 (United States); Luca, Maria; Taggart-Murphy, Laura; Portillio, Jessica; Chang, Cathey; Guven, Ayse [W.M. Keck Science Center, The Claremont Colleges, Claremont, CA 91711 (United States); Lin, Ren-Jang [Department of Molecular and Cellular Biology, Beckman Research Institute of the City of Hope, Duarte, CA 91010 (United States); Murray, Johanne; Carr, Antony [Genome Damage and Stability Center, University of Sussex, Falmer, BN1 9RQ (United Kingdom)

    2012-10-01

    Schizosaccharomyces pombe Dsk1 is an SR protein-specific kinase (SRPK), whose homologs have been identified in every eukaryotic organism examined. Although discovered as a mitotic regulator with protein kinase activity toward SR splicing factors, it remains largely unknown about what and how Dsk1 contributes to cell cycle and pre-mRNA splicing. In this study, we investigated the Dsk1 function by determining interacting factors and cellular localization of the kinase. Consistent with its reported functions, we found that pre-mRNA processing and cell cycle factors are prominent among the proteins co-purified with Dsk1. The identification of these factors led us to find Rsd1 as a novel Dsk1 substrate, as well as the involvement of Dsk1 in cellular distribution of poly(A){sup +} RNA. In agreement with its role in nuclear events, we also found that Dsk1 is mainly localized in the nucleus during G{sub 2} phase and at mitosis. Furthermore, we revealed the oscillation of Dsk1 protein in a cell cycle-dependent manner. This paper marks the first comprehensive analysis of in vivo Dsk1-associated proteins in fission yeast. Our results reflect the conserved role of SRPK family in eukaryotic organisms, and provide information about how Dsk1 functions in pre-mRNA processing and cell-division cycle.

  9. Predictive value of prostate specific antigen in a European HIV-positive cohort

    DEFF Research Database (Denmark)

    Shepherd, Leah; Borges, Álvaro H; Ravn, Lene

    2016-01-01

    BACKGROUND: It is common practice to use prostate specific antigen (PSA) ≥4.0 ng/ml as a clinical indicator for men at risk of prostate cancer (PCa), however, this is unverified in HIV+ men. We aimed to describe kinetics and predictive value of PSA for PCa in HIV+ men. METHODS: A nested case...... control study of 21 men with PCa and 40 matched-controls within EuroSIDA was conducted. Prospectively stored plasma samples before PCa (or matched date in controls) were measured for the following markers: total PSA (tPSA), free PSA (fPSA), testosterone and sex hormone binding globulin (SHBG). Conditional...

  10. Species-specific activity of HIV-1 Vpu and positive selection of tetherin transmembrane domain variants.

    Directory of Open Access Journals (Sweden)

    Matthew W McNatt

    2009-02-01

    Full Text Available Tetherin/BST-2/CD317 is a recently identified antiviral protein that blocks the release of nascent retrovirus, and other virus, particles from infected cells. An HIV-1 accessory protein, Vpu, acts as an antagonist of tetherin. Here, we show that positive selection is evident in primate tetherin sequences and that HIV-1 Vpu appears to have specifically adapted to antagonize variants of tetherin found in humans and chimpanzees. Tetherin variants found in rhesus macaques (rh, African green monkeys (agm and mice were able to inhibit HIV-1 particle release, but were resistant to antagonism by HIV-1 Vpu. Notably, reciprocal exchange of transmembrane domains between human and monkey tetherins conferred sensitivity and resistance to Vpu, identifying this protein domain as a critical determinant of Vpu function. Indeed, differences between hu-tetherin and rh-tetherin at several positions in the transmembrane domain affected sensitivity to antagonism by Vpu. Two alterations in the hu-tetherin transmembrane domain, that correspond to differences found in rh- and agm-tetherin proteins, were sufficient to render hu-tetherin completely resistant to HIV-1 Vpu. Interestingly, transmembrane and cytoplasmic domain sequences in primate tetherins exhibit variation at numerous codons that is likely the result of positive selection, and some of these changes coincide with determinants of HIV-1 Vpu sensitivity. Overall, these data indicate that tetherin could impose a barrier to viral zoonosis as a consequence of positive selection that has been driven by ancient viral antagonists, and that the HIV-1 Vpu protein has specialized to target the transmembrane domains found in human/chimpanzee tetherin proteins.

  11. Species-specific activity of HIV-1 Vpu and positive selection of tetherin transmembrane domain variants.

    Science.gov (United States)

    McNatt, Matthew W; Zang, Trinity; Hatziioannou, Theodora; Bartlett, Mackenzie; Fofana, Ismael Ben; Johnson, Welkin E; Neil, Stuart J D; Bieniasz, Paul D

    2009-02-01

    Tetherin/BST-2/CD317 is a recently identified antiviral protein that blocks the release of nascent retrovirus, and other virus, particles from infected cells. An HIV-1 accessory protein, Vpu, acts as an antagonist of tetherin. Here, we show that positive selection is evident in primate tetherin sequences and that HIV-1 Vpu appears to have specifically adapted to antagonize variants of tetherin found in humans and chimpanzees. Tetherin variants found in rhesus macaques (rh), African green monkeys (agm) and mice were able to inhibit HIV-1 particle release, but were resistant to antagonism by HIV-1 Vpu. Notably, reciprocal exchange of transmembrane domains between human and monkey tetherins conferred sensitivity and resistance to Vpu, identifying this protein domain as a critical determinant of Vpu function. Indeed, differences between hu-tetherin and rh-tetherin at several positions in the transmembrane domain affected sensitivity to antagonism by Vpu. Two alterations in the hu-tetherin transmembrane domain, that correspond to differences found in rh- and agm-tetherin proteins, were sufficient to render hu-tetherin completely resistant to HIV-1 Vpu. Interestingly, transmembrane and cytoplasmic domain sequences in primate tetherins exhibit variation at numerous codons that is likely the result of positive selection, and some of these changes coincide with determinants of HIV-1 Vpu sensitivity. Overall, these data indicate that tetherin could impose a barrier to viral zoonosis as a consequence of positive selection that has been driven by ancient viral antagonists, and that the HIV-1 Vpu protein has specialized to target the transmembrane domains found in human/chimpanzee tetherin proteins.

  12. Induction of multi-epitope specific antibodies against HIV-1 by multi-epitope vaccines

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Some neutralizing antibodies against HIV-1 envelope proteins were highly effective to inhibit the infection of different strains in vitro, and existed in the infected individuals with very low levels. We suggested multi-epitope-vaccine as a new strategy to increase levels of neutralizing antibodies and the abilities against HIV mutation in vivo. Two candidate multi-epitope-vaccines induced antibodies with predefined multi-epitope-specificity in rhesus macaque. These antibodies recognized corresponding neutralizing epitopes on epitope-peptides, gp41 peptides, V3 loop peptide, rsgp41 and rgp120. Besides, three candidate epitope-vaccines in combination (another kind of multi-epitopevaccines) showed similar potency to induce predefined multiple immune responses in rabbits. These results suggest that multi-epitope-vaccines may be a new strategy to induce multi-antiviral activities against HIV-1 infection and mutafions.

  13. Ultrastructural studies of time-course and cellular specificity of interleukin-1 mediated islet cytotoxicity

    DEFF Research Database (Denmark)

    Mandrup-Poulsen, T; Egeberg, J; Nerup, J

    1987-01-01

    Previous electron-microscopic studies of isolated islets of Langerhans exposed to the monokine interleukin-1 for 7 days have indicated that interleukin-1 is cytotoxic to all islet cells. To study the time-course and possible cellular specificity of interleukin-1 cytotoxicity to islets exposed...... to interleukin-1 for short time periods, isolated rat or human islets were incubated with or without 25 U/ml highly purified human interleukin-1 for 24 h. Samples of rat islets were taken after 5 min, 30 min, 1, 2, 4, 6, 8, 10, 12, 16, 20 and 24 h and samples of human islets after 5 min, 30 min and 24 h...... of incubation and examined by electron microscopy in a blinded fashion. Already after 30 min, accumulation of opaque intracytoplasmic bodies without apparent surrounding membranes, and autophagic vacuoles were seen in about 20% of the beta cells examined in rat islets exposed to interleukin-1. After 16 h...

  14. Definition of the viral targets of protective HIV-1-specific T cell responses

    Directory of Open Access Journals (Sweden)

    Mothe Beatriz

    2011-12-01

    Full Text Available Abstract Background The efficacy of the CTL component of a future HIV-1 vaccine will depend on the induction of responses with the most potent antiviral activity and broad HLA class I restriction. However, current HIV vaccine designs are largely based on viral sequence alignments only, not incorporating experimental data on T cell function and specificity. Methods Here, 950 untreated HIV-1 clade B or -C infected individuals were tested for responses to sets of 410 overlapping peptides (OLP spanning the entire HIV-1 proteome. For each OLP, a "protective ratio" (PR was calculated as the ratio of median viral loads (VL between OLP non-responders and responders. Results For both clades, there was a negative relationship between the PR and the entropy of the OLP sequence. There was also a significant additive effect of multiple responses to beneficial OLP. Responses to beneficial OLP were of significantly higher functional avidity than responses to non-beneficial OLP. They also had superior in-vitro antiviral activities and, importantly, were at least as predictive of individuals' viral loads than their HLA class I genotypes. Conclusions The data thus identify immunogen sequence candidates for HIV and provide an approach for T cell immunogen design applicable to other viral infections.

  15. Maintenance of HIV-Specific Memory B-Cell Responses in Elite Controllers Despite Low Viral Burdens.

    Science.gov (United States)

    Buckner, Clarisa M; Kardava, Lela; Zhang, Xiaozhen; Gittens, Kathleen; Justement, J Shawn; Kovacs, Colin; McDermott, Adrian B; Li, Yuxing; Sajadi, Mohammad M; Chun, Tae-Wook; Fauci, Anthony S; Moir, Susan

    2016-08-01

    Human immunodeficiency virus (HIV)-specific B-cell responses in infected individuals are maintained by active HIV replication. Suppression of viremia by antiretroviral therapy (ART) leads to quantitative and qualitative changes that remain unclear. Accordingly, B-cell responses were investigated in elite controllers (ECs), who maintain undetectable HIV levels without ART, and in individuals whose viremia was suppressed by ART. Despite a higher HIV burden in the ART group, compared with the EC group, frequencies of HIV-specific B cells were higher in the EC group, compared with those in the ART group. However, the initiation of ART in several ECs was associated with reduced frequencies of HIV-specific B cells, suggesting that responses are at least in part sustained by HIV replication. Furthermore, B-cell responses to tetanus toxin but not influenza hemagglutinin in the ART group were lower than those in the EC group. Thus, the superior HIV-specific humoral response in ECs versus ART-treated individuals is likely due to a more intact humoral immune response in ECs and/or distinct responses to residual HIV replication.

  16. Trans-cellular introduction of HIV-1 protein Nef induces pathogenic response in Caenorhabditis elegans.

    Directory of Open Access Journals (Sweden)

    Aamir Nazir

    Full Text Available BACKGROUND: Caenorhabditis elegans has emerged as a very powerful model for studying the host pathogen interactions. Despite the absence of a naturally occurring viral infection for C. elegans, the model is now being exploited experimentally to study the basic aspects of virus-host interplay. The data generated from recent studies suggests that the virus that infects mammalian cells does infect, replicate and accumulate in C. elegans. METHODOLOGY/PRINCIPAL FINDINGS: We took advantage of the easy-to-achieve protein introduction in C. elegans and employing the methodology, we administered HIV-1 protein Nef into live worms. Nef is known to be an important protein for exacerbating HIV-1 pathogenesis in host by enhancing viral replication. The deletion of nef from the viral genome has been reported to inhibit its replication in the host, thereby leading to delayed pathogenesis. Our studies, employing Nef introduction into C. elegans, led to creation of an in-vivo model that allowed us to study, whether or not, the protein induces effect in the whole organism. We observed a marked lipodystrophy, effect on neuromuscular function, impaired fertility and reduced longevity in the worms exposed to Nef. The observed effects resemble to those observed in Nef transgenic mice and most interestingly the effects also relate to some of the pathogenic aspects exhibited by human AIDS patients. CONCLUSIONS/SIGNIFICANCE: Our studies underline the importance of this in vivo model for studying the interactions of Nef with host proteins, which could further be used for identifying possible inhibitors of such interactions.

  17. Dual role of TRBP in HIV replication and RNA interference: viral diversion of a cellular pathway or evasion from antiviral immunity?

    Directory of Open Access Journals (Sweden)

    Clerzius Guerline

    2005-10-01

    Full Text Available Abstract Increasing evidence indicates that RNA interference (RNAi may be used to provide antiviral immunity in mammalian cells. Human micro (miRNAs can inhibit the replication of a primate virus, whereas a virally-encoded miRNA from HIV inhibits its own replication. Indirect proof comes from RNAi suppressors encoded by mammalian viruses. Influenza NS1 and Vaccinia E3L proteins can inhibit RNAi in plants, insects and worms. HIV-1 Tat protein and Adenovirus VA RNAs act as RNAi suppressors in mammalian cells. Surprisingly, many RNAi suppressors are also inhibitors of the interferon (IFN-induced protein kinase R (PKR but the potential overlap between the RNAi and the IFN pathways remains to be determined. The link between RNAi as an immune response and the IFN pathway may be formed by a cellular protein, TRBP, which has a dual role in HIV replication and RNAi. TRBP has been isolated as an HIV-1 TAR RNA binding protein that increases HIV expression and replication by inhibiting PKR and by increasing translation of structured RNAs. A recent report published in the Journal of Virology shows that the poor replication of HIV in astrocytes is mainly due to a heightened PKR response that can be overcome by supplying TRBP exogenously. In two recent papers published in Nature and EMBO Reports, TRBP is now shown to interact with Dicer and to be required for RNAi mediated by small interfering (si and micro (miRNAs. The apparent discrepancy between TRBP requirement in RNAi and in HIV replication opens the hypotheses that RNAi may be beneficial for HIV-1 replication or that HIV-1 may evade the RNAi restriction by diverting TRBP from Dicer and use it for its own benefit.

  18. Ceruloplasmin ferroxidase activity stimulates cellular iron uptake by a trivalent cation-specific transport mechanism

    Science.gov (United States)

    Attieh, Z. K.; Mukhopadhyay, C. K.; Seshadri, V.; Tripoulas, N. A.; Fox, P. L.

    1999-01-01

    The balance required to maintain appropriate cellular and tissue iron levels has led to the evolution of multiple mechanisms to precisely regulate iron uptake from transferrin and low molecular weight iron chelates. A role for ceruloplasmin (Cp) in vertebrate iron metabolism is suggested by its potent ferroxidase activity catalyzing conversion of Fe2+ to Fe3+, by identification of yeast copper oxidases homologous to Cp that facilitate high affinity iron uptake, and by studies of "aceruloplasminemic" patients who have extensive iron deposits in multiple tissues. We have recently shown that Cp increases iron uptake by cultured HepG2 cells. In this report, we investigated the mechanism by which Cp stimulates cellular iron uptake. Cp stimulated the rate of non-transferrin 55Fe uptake by iron-deficient K562 cells by 2-3-fold, using a transferrin receptor-independent pathway. Induction of Cp-stimulated iron uptake by iron deficiency was blocked by actinomycin D and cycloheximide, consistent with a transcriptionally induced or regulated transporter. Cp-stimulated iron uptake was completely blocked by unlabeled Fe3+ and by other trivalent cations including Al3+, Ga3+, and Cr3+, but not by divalent cations. These results indicate that Cp utilizes a trivalent cation-specific transporter. Cp ferroxidase activity was required for iron uptake as shown by the ineffectiveness of two ferroxidase-deficient Cp preparations, copper-deficient Cp and thiomolybdate-treated Cp. We propose a model in which iron reduction and subsequent re-oxidation by Cp are essential for an iron uptake pathway with high ion specificity.

  19. Cell-type specific DNA methylation patterns define human breast cellular identity.

    Directory of Open Access Journals (Sweden)

    Petr Novak

    Full Text Available DNA methylation plays a role in a variety of biological processes including embryonic development, imprinting, X-chromosome inactivation, and stem cell differentiation. Tissue specific differential methylation has also been well characterized. We sought to extend these studies to create a map of differential DNA methylation between different cell types derived from a single tissue. Using three pairs of isogenic human mammary epithelial and fibroblast cells, promoter region DNA methylation was characterized using MeDIP coupled to microarray analysis. Comparison of DNA methylation between these cell types revealed nearly three thousand cell-type specific differentially methylated regions (ctDMRs. MassARRAY was performed upon 87 ctDMRs to confirm and quantify differential DNA methylation. Each of the examined regions exhibited statistically significant differences ranging from 10-70%. Gene ontology analysis revealed the overrepresentation of many transcription factors involved in developmental processes. Additionally, we have shown that ctDMRs are associated with histone related epigenetic marks and are often aberrantly methylated in breast cancer. Overall, our data suggest that there are thousands of ctDMRs which consistently exhibit differential DNA methylation and may underlie cell type specificity in human breast tissue. In addition, we describe the pathways affected by these differences and provide insight into the molecular mechanisms and physiological overlap between normal cellular differentiation and breast carcinogenesis.

  20. Non-specific cellular uptake of surface-functionalized quantum dots

    Energy Technology Data Exchange (ETDEWEB)

    Kelf, T A; Sreenivasan, V K A; Sun, J; Goldys, E M; Zvyagin, A V [MQ Photonics Centre, Faculty of Science, Macquarie University, Sydney (Australia); Kim, E J, E-mail: azvyagin@science.mq.edu.au [Department of Science Education-Chemical Education Major, Daegu University, Gyeonbuk (Korea, Republic of)

    2010-07-16

    We report a systematic empirical study of nanoparticle internalization into cells via non-specific pathways. The nanoparticles were comprised of commercial quantum dots (QDs) that were highly visible under a fluorescence confocal microscope. Surface-modified QDs with basic biologically significant moieties, e.g. carboxyl, amino, and streptavidin, were used, in combination with surface derivatization with polyethylene glycol (PEG) for a range of immortalized cell lines. Internalization rates were derived from image analysis and a detailed discussion about the effect of nanoparticle size, charge and surface groups is presented. We find that PEG derivatization dramatically suppresses the non-specific uptake while PEG-free carboxyl and amine functional groups promote QD internalization. These uptake variations displayed a remarkable consistency across different cell types. The reported results are important for experiments concerned with cellular uptake of surface-functionalized nanomaterials, both when non-specific internalization is undesirable and when it is intended for material to be internalized as efficiently as possible.

  1. Cellular and functional specificity among ferritin-like proteins in the multicellular cyanobacterium Nostoc punctiforme.

    Science.gov (United States)

    Ekman, Martin; Sandh, Gustaf; Nenninger, Anja; Oliveira, Paulo; Stensjö, Karin

    2014-03-01

    Ferritin-like proteins constitute a remarkably heterogeneous protein family, including ferritins, bacterioferritins and Dps proteins. The genome of the filamentous heterocyst-forming cyanobacterium Nostoc punctiforme encodes five ferritin-like proteins. In the present paper, we report a multidimensional characterization of these proteins. Our phylogenetic and bioinformatics analyses suggest both structural and physiological differences among the ferritin-like proteins. The expression of these five genes responded differently to hydrogen peroxide treatment, with a significantly higher rise in transcript level for Npun_F3730 as compared with the other four genes. A specific role for Npun_F3730 in the cells tolerance against hydrogen peroxide was also supported by the inactivation of Npun_F3730, Npun_R5701 and Npun_R6212; among these, only the ΔNpun_F3730 strain showed an increased sensitivity to hydrogen peroxide compared with wild type. Analysis of promoter-GFP reporter fusions of the ferritin-like genes indicated that Npun_F3730 and Npun_R5701 were expressed in all cell types of a diazotrophic culture, while Npun_F6212 was expressed specifically in heterocysts. Our study provides the first comprehensive analysis combining functional differentiation and cellular specificity within this important group of proteins in a multicellular cyanobacterium. © 2013 John Wiley & Sons Ltd and Society for Applied Microbiology.

  2. Sensitivity and specificity of point-of-care rapid combination syphilis-HIV-HCV tests.

    Directory of Open Access Journals (Sweden)

    Kristen L Hess

    Full Text Available New rapid point-of-care (POC tests are being developed that would offer the opportunity to increase screening and treatment of several infections, including syphilis. This study evaluated three of these new rapid POC tests at a site in Southern California.Participants were recruited from a testing center in Long Beach, California. A whole blood specimen was used to evaluate the performance of the Dual Path Platform (DPP Syphilis Screen & Confirm, DPP HIV-Syphilis, and DPP HIV-HCV-Syphilis rapid tests. The gold-standard comparisons were Treponema pallidum passive particle agglutination (TPPA, rapid plasma reagin (RPR, HCV enzyme immunoassay (EIA, and HIV-1/2 EIA.A total of 948 whole blood specimens were analyzed in this study. The sensitivity of the HIV tests ranged from 95.7-100% and the specificity was 99.7-100%. The sensitivity and specificity of the HCV test were 91.8% and 99.3%, respectively. The treponemal-test sensitivity when compared to TPPA ranged from 44.0-52.7% and specificity was 98.7-99.6%. The non-treponemal test sensitivity and specificity when compared to RPR was 47.8% and 98.9%, respectively. The sensitivity of the Screen & Confirm test improved to 90.0% when cases who were both treponemal and nontreponemal positive were compared to TPPA+/RPR ≥ 1 ∶ 8.The HIV and HCV on the multi-infection tests showed good performance, but the treponemal and nontreponemal tests had low sensitivity. These results could be due to a low prevalence of active syphilis in the sample population because the sensitivity improved when the gold standard was limited to those more likely to be active cases. Further evaluation of the new syphilis POC tests is required before implementation into testing programs.

  3. HIVIS-DNA or HIVISopt-DNA priming followed by CMDR vaccinia-based boosts induce both humoral and cellular murine immune responses to HIV

    Directory of Open Access Journals (Sweden)

    J Hinkula

    2017-06-01

    Conclusions: HIVIS-DNA was modified to obtain HIVISopt-DNA that had fewer plasmids, and additional epitopes. Even with one DNA prime followed by two MVA-CMDR boosts, humoral and cell-mediated immune responses were readily induced by priming with either DNA construct composition. Priming by HIV-DNA augmented neutralizing antibody responses revealed by boosting with the vaccinia-based heterologous sequences. Cellular and antibody responses covered selected strains representing HIV-1 subtypes A, B, C and CRF01_AE. We assume this is related to the inclusion of heterologous full genes in the vaccine schedule.

  4. Women-specific HIV/AIDS services: identifying and defining the components of holistic service delivery for women living with HIV/AIDS

    Directory of Open Access Journals (Sweden)

    Allison J Carter

    2013-01-01

    Full Text Available Introduction: The increasing proportion of women living with HIV has evoked calls for tailored services that respond to women's specific needs. The objective of this investigation was to explore the concept of women-specific HIV/AIDS services to identify and define what key elements underlie this approach to care. Methods: A comprehensive review was conducted using online databases (CSA Social Service Abstracts, OvidSP, Proquest, Psycinfo, PubMed, CINAHL, augmented with a search for grey literature. In total, 84 articles were retrieved and 30 were included for a full review. Of these 30, 15 were specific to HIV/AIDS, 11 for mental health and addictions and four stemmed from other disciplines. Results and discussion: The review demonstrated the absence of a consensual definition of women-specific HIV/AIDS services in the literature. We distilled this concept into its defining features and 12 additional dimensions (1 creating an atmosphere of safety, respect and acceptance; (2 facilitating communication and interaction among peers; (3 involving women in the planning, delivery and evaluation of services; (4 providing self-determination opportunities; (5 providing tailored programming for women; (6 facilitating meaningful access to care through the provision of social and supportive services; (7 facilitating access to women-specific and culturally sensitive information; (8 considering family as the unit of intervention; (9 providing multidisciplinary integration and coordination of a comprehensive array of services; (10 meeting women “where they are”; (11 providing gender-, culture- and HIV-sensitive training to health and social care providers; and (12 conducting gendered HIV/AIDS research. Conclusions: This review highlights that the concept of women-specific HIV/AIDS services is a complex and multidimensional one that has been shaped by diverse theoretical perspectives. Further research is needed to better understand this emerging concept and

  5. Women-specific HIV/AIDS services: identifying and defining the components of holistic service delivery for women living with HIV/AIDS

    Science.gov (United States)

    Carter, Allison J; Bourgeois, Sonya; O'Brien, Nadia; Abelsohn, Kira; Tharao, Wangari; Greene, Saara; Margolese, Shari; Kaida, Angela; Sanchez, Margarite; Palmer, Alexis K; Cescon, Angela; de Pokomandy, Alexandra; Loutfy, Mona R

    2013-01-01

    Introduction The increasing proportion of women living with HIV has evoked calls for tailored services that respond to women's specific needs. The objective of this investigation was to explore the concept of women-specific HIV/AIDS services to identify and define what key elements underlie this approach to care. Methods A comprehensive review was conducted using online databases (CSA Social Service Abstracts, OvidSP, Proquest, Psycinfo, PubMed, CINAHL), augmented with a search for grey literature. In total, 84 articles were retrieved and 30 were included for a full review. Of these 30, 15 were specific to HIV/AIDS, 11 for mental health and addictions and four stemmed from other disciplines. Results and discussion The review demonstrated the absence of a consensual definition of women-specific HIV/AIDS services in the literature. We distilled this concept into its defining features and 12 additional dimensions (1) creating an atmosphere of safety, respect and acceptance; (2) facilitating communication and interaction among peers; (3) involving women in the planning, delivery and evaluation of services; (4) providing self-determination opportunities; (5) providing tailored programming for women; (6) facilitating meaningful access to care through the provision of social and supportive services; (7) facilitating access to women-specific and culturally sensitive information; (8) considering family as the unit of intervention; (9) providing multidisciplinary integration and coordination of a comprehensive array of services; (10) meeting women “where they are”; (11) providing gender-, culture- and HIV-sensitive training to health and social care providers; and (12) conducting gendered HIV/AIDS research. Conclusions This review highlights that the concept of women-specific HIV/AIDS services is a complex and multidimensional one that has been shaped by diverse theoretical perspectives. Further research is needed to better understand this emerging concept and ultimately

  6. Women-specific HIV/AIDS services: identifying and defining the components of holistic service delivery for women living with HIV/AIDS.

    Science.gov (United States)

    Carter, Allison J; Bourgeois, Sonya; O'Brien, Nadia; Abelsohn, Kira; Tharao, Wangari; Greene, Saara; Margolese, Shari; Kaida, Angela; Sanchez, Margarite; Palmer, Alexis K; Cescon, Angela; de Pokomandy, Alexandra; Loutfy, Mona R

    2013-01-11

    The increasing proportion of women living with HIV has evoked calls for tailored services that respond to women's specific needs. The objective of this investigation was to explore the concept of women-specific HIV/AIDS services to identify and define what key elements underlie this approach to care. A comprehensive review was conducted using online databases (CSA Social Service Abstracts, OvidSP, Proquest, Psycinfo, PubMed, CINAHL), augmented with a search for grey literature. In total, 84 articles were retrieved and 30 were included for a full review. Of these 30, 15 were specific to HIV/AIDS, 11 for mental health and addictions and four stemmed from other disciplines. The review demonstrated the absence of a consensual definition of women-specific HIV/AIDS services in the literature. We distilled this concept into its defining features and 12 additional dimensions (1) creating an atmosphere of safety, respect and acceptance; (2) facilitating communication and interaction among peers; (3) involving women in the planning, delivery and evaluation of services; (4) providing self-determination opportunities; (5) providing tailored programming for women; (6) facilitating meaningful access to care through the provision of social and supportive services; (7) facilitating access to women-specific and culturally sensitive information; (8) considering family as the unit of intervention; (9) providing multidisciplinary integration and coordination of a comprehensive array of services; (10) meeting women "where they are"; (11) providing gender-, culture- and HIV-sensitive training to health and social care providers; and (12) conducting gendered HIV/AIDS research. This review highlights that the concept of women-specific HIV/AIDS services is a complex and multidimensional one that has been shaped by diverse theoretical perspectives. Further research is needed to better understand this emerging concept and ultimately assess the effectiveness of women-specific services on HIV

  7. The Cleavage and Polyadenylation Specificity Factor 6 (CPSF6) Subunit of the Capsid-recruited Pre-messenger RNA Cleavage Factor I (CFIm) Complex Mediates HIV-1 Integration into Genes.

    Science.gov (United States)

    Rasheedi, Sheeba; Shun, Ming-Chieh; Serrao, Erik; Sowd, Gregory A; Qian, Juan; Hao, Caili; Dasgupta, Twishasri; Engelman, Alan N; Skowronski, Jacek

    2016-05-27

    HIV-1 favors integration into active genes and gene-enriched regions of host cell chromosomes, thus maximizing the probability of provirus expression immediately after integration. This requires cleavage and polyadenylation specificity factor 6 (CPSF6), a cellular protein involved in pre-mRNA 3' end processing that binds HIV-1 capsid and connects HIV-1 preintegration complexes to intranuclear trafficking pathways that link integration to transcriptionally active chromatin. CPSF6 together with CPSF5 and CPSF7 are known subunits of the cleavage factor I (CFIm) 3' end processing complex; however, CPSF6 could participate in additional protein complexes. The molecular mechanisms underpinning the role of CPSF6 in HIV-1 infection remain to be defined. Here, we show that a majority of cellular CPSF6 is incorporated into the CFIm complex. HIV-1 capsid recruits CFIm in a CPSF6-dependent manner, which suggests that the CFIm complex mediates the known effects of CPSF6 in HIV-1 infection. To dissect the roles of CPSF6 and other CFIm complex subunits in HIV-1 infection, we analyzed virologic and integration site targeting properties of a CPSF6 variant with mutations that prevent its incorporation into CFIm We show, somewhat surprisingly, that CPSF6 incorporation into CFIm is not required for its ability to direct preferential HIV-1 integration into genes. The CPSF5 and CPSF7 subunits appear to have only a minor, if any, role in this process even though they appear to facilitate CPSF6 binding to capsid. Thus, CPSF6 alone controls the key molecular interactions that specify HIV-1 preintegration complex trafficking to active chromatin.

  8. Identification of different binding sites in the dendritic cell-specific receptor DC-SIGN for intercellular adhesion molecule 3 and HIV-1.

    NARCIS (Netherlands)

    Geijtenbeek, T.B.; Duijnhoven, G.C.F. van; Vliet, S. van; Krieger, E.; Vriend, G.; Figdor, C.G.; Kooyk, Y. van

    2002-01-01

    The novel dendritic cell (DC)-specific human immunodeficiency virus type 1 (HIV-1) receptor DC-SIGN plays a key role in the dissemination of HIV-1 by DC. DC-SIGN is thought to capture HIV-1 at mucosal sites of entry, facilitating transport to lymphoid tissues, where DC-SIGN efficiently transmits HIV

  9. Identification of different binding sites in the dendritic cell-specific receptor DC-SIGN for intercellular adhesion molecule 3 and HIV-1.

    NARCIS (Netherlands)

    Geijtenbeek, T.B.; Duijnhoven, G.C.F. van; Vliet, S. van; Krieger, E.; Vriend, G.; Figdor, C.G.; Kooyk, Y. van

    2002-01-01

    The novel dendritic cell (DC)-specific human immunodeficiency virus type 1 (HIV-1) receptor DC-SIGN plays a key role in the dissemination of HIV-1 by DC. DC-SIGN is thought to capture HIV-1 at mucosal sites of entry, facilitating transport to lymphoid tissues, where DC-SIGN efficiently transmits HIV

  10. Reduced Treponema pallidum–Specific Opsonic Antibody Activity in HIV-Infected Patients With Syphilis

    Science.gov (United States)

    Marra, Christina M.; Tantalo, Lauren C.; Sahi, Sharon K.; Dunaway, Shelia B.; Lukehart, Sheila A.

    2016-01-01

    Background. Human immunodeficiency virus (HIV)–infected individuals may have poorer serological responses to syphilis treatment and may be more likely to experience neurosyphilis. Treponema pallidum is cleared from sites of infection by opsonization, ingestion, and killing by macrophages. Methods. Serum samples from 235 individuals with syphilis were tested for T. pallidum–specific opsonic activity. Blood T. pallidum concentrations were determined by real-time polymerase chain reaction amplification of the tp0574 gene, and T. pallidum was detected in cerebrospinal fluid (CSF) by reverse-transcriptase polymerase chain reaction of 16S ribosomal RNA. Results. Opsonic activity was higher with higher serum rapid plasma reagin titers (P VDRL reactivity. Conclusions. Serum T. pallidum–specific opsonic activity is significantly lower in HIV-infected individuals. Impaired T. pallidum–specific immune responses could contribute to differences in the course of disease or treatment response. PMID:26655298

  11. Co-infection with Mycobacterium tuberculosis impairs HIV-Specific CD8+ and CD4+ T cell functionality.

    Science.gov (United States)

    Chetty, Shivan; Govender, Pamla; Zupkosky, Jennifer; Pillay, Mona; Ghebremichael, Musie; Moosa, Mahomed-Yunus S; Ndung'u, Thumbi; Porichis, Filippos; Kasprowicz, Victoria O

    2015-01-01

    The ability of antigen-specific T cells to simultaneously produce multiple cytokines is thought to correlate with the functional capacity and efficacy of T cells. These 'polyfunctional' T cells have been associated with control of HIV. We aimed to assess the impact of co-infection with Mycobacterium tuberculosis (MTB) on HIV-specific CD8+ and CD4+ T cell function. We assessed T cell functionality in 34 South African adults by investigating the IFN-y, IL-2, TNF-α, IL-21 and IL-17 cytokine secretion capacity, using polychromatic flow cytometry, following HIV Gag-specific stimulation of peripheral blood mononuclear cells. We show that MTB is associated with lower HIV-specific T cell function in co-infected as compared to HIV mono-infected individuals. This decline in function was greatest in co-infection with active Tuberculosis (TB) compared to co-infection with latent MTB (LTBI), suggesting that mycobacterial load may contribute to this loss of function. The described impact of MTB on HIV-specific T cell function may be a mechanism for increased HIV disease progression in co-infected subjects as functionally impaired T cells may be less able to control HIV.

  12. Co-infection with Mycobacterium tuberculosis impairs HIV-Specific CD8+ and CD4+ T cell functionality.

    Directory of Open Access Journals (Sweden)

    Shivan Chetty

    Full Text Available The ability of antigen-specific T cells to simultaneously produce multiple cytokines is thought to correlate with the functional capacity and efficacy of T cells. These 'polyfunctional' T cells have been associated with control of HIV. We aimed to assess the impact of co-infection with Mycobacterium tuberculosis (MTB on HIV-specific CD8+ and CD4+ T cell function. We assessed T cell functionality in 34 South African adults by investigating the IFN-y, IL-2, TNF-α, IL-21 and IL-17 cytokine secretion capacity, using polychromatic flow cytometry, following HIV Gag-specific stimulation of peripheral blood mononuclear cells. We show that MTB is associated with lower HIV-specific T cell function in co-infected as compared to HIV mono-infected individuals. This decline in function was greatest in co-infection with active Tuberculosis (TB compared to co-infection with latent MTB (LTBI, suggesting that mycobacterial load may contribute to this loss of function. The described impact of MTB on HIV-specific T cell function may be a mechanism for increased HIV disease progression in co-infected subjects as functionally impaired T cells may be less able to control HIV.

  13. Biomaterial design for specific cellular interactions: Role of surface functionalization and geometric features

    Science.gov (United States)

    Kolhar, Poornima

    The areas of drug delivery and tissue engineering have experienced extraordinary growth in recent years with the application of engineering principles and their potential to support and improve the field of medicine. The tremendous progress in nanotechnology and biotechnology has lead to this explosion of research and development in biomedical applications. Biomaterials can now be engineered at a nanoscale and their specific interactions with the biological tissues can be modulated. Various design parameters are being established and researched for design of drug-delivery carriers and scaffolds to be implanted into humans. Nanoparticles made from versatile biomaterial can deliver both small-molecule drugs and various classes of bio-macromolecules, such as proteins and oligonucleotides. Similarly in the field of tissue engineering, current approaches emphasize nanoscale control of cell behavior by mimicking the natural extracellular matrix (ECM) unlike, traditional scaffolds. Drug delivery and tissue engineering are closely connected fields and both of these applications require materials with exceptional physical, chemical, biological, and biomechanical properties to provide superior therapy. In the current study the surface functionalization and the geometric features of the biomaterials has been explored. In particular, a synthetic surface for culture of human embryonic stem cells has been developed, demonstrating the importance of surface functionalization in maintaining the pluripotency of hESCs. In the second study, the geometric features of the drug delivery carriers are investigated and the polymeric nanoneedles mediated cellular permeabilization and direct cytoplasmic delivery is reported. In the third study, the combined effect of surface functionalization and geometric modification of carriers for vascular targeting is enunciated. These studies illustrate how the biomaterials can be designed to achieve various cellular behaviors and control the

  14. Role of SUMO-specific protease 2 in reprogramming cellular glucose metabolism.

    Directory of Open Access Journals (Sweden)

    Shuang Tang

    Full Text Available Most cancer cells exhibit a shift in glucose metabolic strategy, displaying increased glycolysis even with adequate oxygen supply. SUMO-specific proteases (SENPs de-SUMOylate substrates including HIF1α and p53,two key regulators in cancer glucose metabolism, to regulate their activity, stability and subcellular localization. However, the role of SENPs in tumor glucose metabolism remains unclear. Here we report that SUMO-specific protease 2 (SENP2 negatively regulates aerobic glycolysis in MCF7 and MEF cells. Over-expression of SENP2 reduces the glucose uptake and lactate production, increasing the cellular ATP levels in MCF7 cells, while SENP2 knockout MEF cells show increased glucose uptake and lactate production along with the decreased ATP levels. Consistently, the MCF7 cells over-expressing SENP2 exhibit decreased expression levels of key glycolytic enzymes and an increased rate of glucose oxidation compared with control MCF7 cells, indicating inhibited glycolysis but enhanced oxidative mitochondrial respiration. Moreover, SENP2 over-expressing MCF7 cells demonstrated a reduced amount of phosphorylated AKT, whereas SENP2 knockout MEFs exhibit increased levels of phosphorylated AKT. Furthermore, inhibiting AKT phosphorylation by LY294002 rescued the phenotype induced by SENP2 deficiency in MEFs. In conclusion, SENP2 represses glycolysis and shifts glucose metabolic strategy, in part through inhibition of AKT phosphorylation. Our study reveals a novel function of SENP2 in regulating glucose metabolism.

  15. CELLULAR LOCALIZATION OF IMMUNOGLOBULINS WITH DIFFERENT ALLOTYPIC SPECIFICITIES IN RABBIT LYMPHOID TISSUES

    Science.gov (United States)

    Pernis, Benvenuto; Chiappino, Gerolamo; Kelus, Andrew S.; Gell, Philip G. H.

    1965-01-01

    The cellular localization of allotypes in rabbit lymphoid tissues has been studied by immunofluorescence. In heterozygous animals the double staining for two allotypes controlled by allelic genes (A1 and A2; A4 and A5; A4 and A6) has shown the existence of two populations of plasma cells, one containing one allotype and the other the alternative one. The localization in different cells of immunoglobulins marked by allelic allotypic specificities has been confirmed by microspectrography of single cells. An exception to this rule was given by the presence in the germinal centers of lymphoid follicles of apparently uniform mixtures of products of the two allelic genes. Double staining for two allotypes controlled by genes at different loci showed, instead, the presence of many cells containing both allotypes; the number of these cells was highest in doubly homozygotes, in the other it was consistent with random association of non-allelic specificities. In addition double staining for one allotype and gamma G globulins in the lymphoid tissues of rabbits homozygous at the a or at the b locus, has shown the presence of cells containing immunoglobulins that lack one allotype. PMID:4159057

  16. Rapid in vitro detection of HIV-1-specific antibody secretion by cells-culture with virus antigens

    Directory of Open Access Journals (Sweden)

    Adele Caterino-de-Araujo

    1992-06-01

    Full Text Available The present report describes an alternative method for in vitro detection of HIV-1 -specific antibody secretion in 24h of culture employing as stimulant of peripheral blood mononuclear cells the disrupted inactivated whole virus adsorbed onto microwells in a commercial ELISA kit plates. The results obtained from this technique have showed high sensitivity and specificity since it was capable of detecting HIV-1 infection early after birth. There were neither false-positivity nor false-negativity when blood samples obtained from HIV-1 seronegative asymptomatic individuals, and HIV-1 seropositive adult patients were analized. This rapid, low cost, simple, highly sensitive and specific assay can be extremely useful for early diagnosis of pediatric HIV infection.

  17. Characterization of HIV-Specific CD4+T Cell Responses against Peptides Selected with Broad Population and Pathogen Coverage

    DEFF Research Database (Denmark)

    Buggert, Marcus; Norstrom, Melissa M.; Czarnecki, Chris

    2012-01-01

    CD4+ T cells orchestrate immunity against viral infections, but their importance in HIV infection remains controversial. Nevertheless, comprehensive studies have associated increase in breadth and functional characteristics of HIV-specific CD4+ T cells with decreased viral load. A major challenge...

  18. Cause-specific excess mortality in siblings of patients co-infected with HIV and hepatitis C virus

    DEFF Research Database (Denmark)

    Hansen, Ann-Brit Eg; Lohse, Nicolai; Gerstoft, Jan;

    2007-01-01

    BACKGROUND: Co-infection with hepatitis C in HIV-infected individuals is associated with 3- to 4-fold higher mortality among these patients' siblings, compared with siblings of mono-infected HIV-patients or population controls. This indicates that risk factors shared by family members partially...... account for the excess mortality of HIV/HCV-co-infected patients. We aimed to explore the causes of death contributing to the excess sibling mortality. METHODOLOGY AND PRINCIPAL FINDINGS: We retrieved causes of death from the Danish National Registry of Deaths and estimated cause-specific excess mortality...... rates (EMR) for siblings of HIV/HCV-co-infected individuals (n = 436) and siblings of HIV mono-infected individuals (n = 1837) compared with siblings of population controls (n = 281,221). Siblings of HIV/HCV-co-infected individuals had an all-cause EMR of 3.03 (95% CI, 1.56-4.50) per 1,000 person...

  19. Autocrine production of beta-chemokines protects CMV-Specific CD4 T cells from HIV infection.

    Directory of Open Access Journals (Sweden)

    Joseph P Casazza

    2009-10-01

    Full Text Available Induction of a functional subset of HIV-specific CD4+ T cells that is resistant to HIV infection could enhance immune protection and decrease the rate of HIV disease progression. CMV-specific CD4+ T cells, which are less frequently infected than HIV-specific CD4+ T cells, are a model for such an effect. To determine the mechanism of this protection, we compared the functional response of HIV gag-specific and CMV pp65-specific CD4+ T cells in individuals co-infected with CMV and HIV. We found that CMV-specific CD4+ T cells rapidly up-regulated production of MIP-1alpha and MIP-1beta mRNA, resulting in a rapid increase in production of MIP-1alpha and MIP-1beta after cognate antigen stimulation. Production of beta-chemokines was associated with maturational phenotype and was rarely seen in HIV-specific CD4+ T cells. To test whether production of beta-chemokines by CD4+ T cells lowers their susceptibility to HIV infection, we measured cell-associated Gag DNA to assess the in vivo infection history of CMV-specific CD4+ T cells. We found that CMV-specific CD4+ T cells which produced MIP-1beta contained 10 times less Gag DNA than did those which failed to produce MIP-1beta. These data suggest that CD4+ T cells which produce MIP-1alpha and MIP-1beta bind these chemokines in an autocrine fashion which decreases the risk of in vivo HIV infection.

  20. Impact of chemotherapy for HIV-1 related lymphoma on residual viremia and cellular HIV-1 DNA in patients on suppressive antiretroviral therapy.

    Directory of Open Access Journals (Sweden)

    Anthony R Cillo

    Full Text Available The first cure of HIV-1 infection was achieved through complex, multimodal therapy including myeloablative chemotherapy, total body irradiation, anti-thymocyte globulin, and allogeneic stem cell transplantation with a CCR5 delta32 homozygous donor. The contributions of each component of this therapy to HIV-1 eradication are unclear. To assess the impact of cytotoxic chemotherapy alone on HIV-1 persistence, we longitudinally evaluated low-level plasma viremia and HIV-1 DNA in PBMC from patients in the ACTG A5001/ALLRT cohort on suppressive antiretroviral therapy (ART who underwent chemotherapy for HIV-1 related lymphoma without interrupting ART. Plasma HIV-1 RNA, total HIV-1 DNA and 2-LTR circles (2-LTRs in PBMC were measured using sensitive qPCR assays. In the 9 patients who received moderately intensive chemotherapy for HIV-1 related lymphoma with uninterrupted ART, low-level plasma HIV-1 RNA did not change significantly with chemotherapy: median HIV-1 RNA was 1 copy/mL (interquartile range: 1.0 to 20 pre-chemotherapy versus 4 copies/mL (interquartile range: 1.0 to 7.0 post-chemotherapy. HIV-1 DNA levels also did not change significantly, with median pre-chemotherapy HIV-1 DNA of 355 copies/106 CD4+ cells versus 228 copies/106 CD4+ cells post-chemotherapy. 2-LTRs were detectable in 2 of 9 patients pre-chemotherapy and in 3 of 9 patients post-chemotherapy. In summary, moderately intensive chemotherapy for HIV-1 related lymphoma in the context of continuous ART did not have a prolonged impact on HIV-1 persistence. Clinical trials registration unique identifier: NCT00001137.

  1. Impact of chemotherapy for HIV-1 related lymphoma on residual viremia and cellular HIV-1 DNA in patients on suppressive antiretroviral therapy.

    Science.gov (United States)

    Cillo, Anthony R; Krishnan, Supriya; McMahon, Deborah K; Mitsuyasu, Ronald T; Para, Michael F; Mellors, John W

    2014-01-01

    The first cure of HIV-1 infection was achieved through complex, multimodal therapy including myeloablative chemotherapy, total body irradiation, anti-thymocyte globulin, and allogeneic stem cell transplantation with a CCR5 delta32 homozygous donor. The contributions of each component of this therapy to HIV-1 eradication are unclear. To assess the impact of cytotoxic chemotherapy alone on HIV-1 persistence, we longitudinally evaluated low-level plasma viremia and HIV-1 DNA in PBMC from patients in the ACTG A5001/ALLRT cohort on suppressive antiretroviral therapy (ART) who underwent chemotherapy for HIV-1 related lymphoma without interrupting ART. Plasma HIV-1 RNA, total HIV-1 DNA and 2-LTR circles (2-LTRs) in PBMC were measured using sensitive qPCR assays. In the 9 patients who received moderately intensive chemotherapy for HIV-1 related lymphoma with uninterrupted ART, low-level plasma HIV-1 RNA did not change significantly with chemotherapy: median HIV-1 RNA was 1 copy/mL (interquartile range: 1.0 to 20) pre-chemotherapy versus 4 copies/mL (interquartile range: 1.0 to 7.0) post-chemotherapy. HIV-1 DNA levels also did not change significantly, with median pre-chemotherapy HIV-1 DNA of 355 copies/106 CD4+ cells versus 228 copies/106 CD4+ cells post-chemotherapy. 2-LTRs were detectable in 2 of 9 patients pre-chemotherapy and in 3 of 9 patients post-chemotherapy. In summary, moderately intensive chemotherapy for HIV-1 related lymphoma in the context of continuous ART did not have a prolonged impact on HIV-1 persistence. Clinical trials registration unique identifier: NCT00001137.

  2. HIV Skews the Lineage-Defining Transcriptional Profile of Mycobacterium tuberculosis-Specific CD4+ T Cells.

    Science.gov (United States)

    Riou, Catherine; Strickland, Natalie; Soares, Andreia P; Corleis, Björn; Kwon, Douglas S; Wherry, E John; Wilkinson, Robert J; Burgers, Wendy A

    2016-04-01

    HIV-infected persons are at greater risk of developing tuberculosis (TB) even before profound CD4 loss occurs, suggesting that HIV alters CD4(+) T cell functions capable of containing bacterial replication. An effective immune response to Mycobacterium tuberculosis most likely relies on the development of a balanced CD4 response, in which distinct CD4(+) Th subsets act in synergy to control the infection. To define the diversity of M. tuberculosis-specific CD4(+) Th subsets and determine whether HIV infection impacts such responses, the expression of lineage-defining transcription factors T-bet, Gata3, RORγt, and Foxp3 was measured in M. tuberculosis-specific CD4(+) T cells in HIV-uninfected (n = 20) and HIV-infected individuals (n = 20) with latent TB infection. Our results show that, upon 5-d restimulation in vitro, M. tuberculosis-specific CD4(+) T cells from healthy individuals have the ability to exhibit a broad spectrum of Th subsets, defined by specific patterns of transcription factor coexpression. These transcription factor profiles were skewed in HIV-infected individuals where the proportion of T-bet(high)Foxp3(+) M. tuberculosis-specific CD4(+) T cells was significantly decreased (p = 0.002) compared with HIV-uninfected individuals, a change that correlated inversely with HIV viral load (p = 0.0007) and plasma TNF-α (p = 0.027). Our data demonstrate an important balance in Th subset diversity defined by lineage-defining transcription factor coexpression profiles that is disrupted by HIV infection and suggest a role for HIV in impairing TB immunity by altering the equilibrium of M. tuberculosis-specific CD4(+) Th subsets.

  3. Pokeweed antiviral protein restores levels of cellular APOBEC3G during HIV-1 infection by depurinating Vif mRNA.

    Science.gov (United States)

    Krivdova, Gabriela; Hudak, Katalin A

    2015-10-01

    Pokeweed antiviral protein (PAP) is an RNA glycosidase that inhibits production of human immunodeficiency virus type 1 (HIV-1) when expressed in human culture cells. Previously, we showed that the expression of PAP reduced the levels of several viral proteins, including virion infectivity factor (Vif). However, the mechanism causing Vif reduction and the consequences of the inhibition were not determined. Here we show that the Vif mRNA is directly depurinated by PAP. Because of depurination at two specific sites within the Vif ORF, Vif levels decrease during infections and the progeny viruses that are generated are ∼ 10-fold less infectious and compromised for proviral integration. These results are consistent with PAP activity inhibiting translation of Vif, which in turn reduces the effect of Vif to inactivate the host restriction factor APOBEC3G (apolipoprotein B mRNA-editing enzyme, catalytic polypeptide-like editing complex 3G). Our findings identify Vif mRNA as a new substrate for PAP and demonstrate that derepression of innate immunity against HIV-1 contributes to its antiviral activity.

  4. Intermolecular masking of the HIV-1 Rev NLS by the cellular protein HIC: novel insights into the regulation of Rev nuclear import.

    LENUS (Irish Health Repository)

    Gu, Lili

    2011-01-01

    The HIV-1 regulatory protein Rev, which is essential for viral replication, mediates the nuclear export of unspliced viral transcripts. Rev nuclear function requires active nucleocytoplasmic shuttling, and Rev nuclear import is mediated by the recognition of its Nuclear Localisation Signal (NLS) by multiple import factors, which include transportin and importin β. However, it remains unclear which nuclear import pathway(s) predominate in vivo, and the cellular environment that modulates Rev nucleocytoplasmic shuttling remains to be characterised.

  5. Ibalizumab, a CD4-specific mAb to inhibit HIV-1 infection.

    Science.gov (United States)

    Dimitrov, Anthony

    2007-08-01

    Tanox Inc (under license from Biogen Idec, formerly Biogen Inc) is developing ibalizumab, an intravenous, humanized, monoclonal antibody specific for CD4, for the potential treatment of HIV infection. In August 2006, the FDA advised Tanox to conduct additional dose-finding studies, from which data could potentially be used in a BLA filing. Ibalizumab had reached phase II clinical trials; however, there are currently no ongoing clinical trials.

  6. Dynamics of the HIV infection under antiretroviral therapy: A cellular automata approach

    Science.gov (United States)

    González, Ramón E. R.; Coutinho, Sérgio; Zorzenon dos Santos, Rita Maria; de Figueirêdo, Pedro Hugo

    2013-10-01

    The dynamics of human immunodeficiency virus infection under antiretroviral therapy is investigated using a cellular automata model where the effectiveness of each drug is self-adjusted by the concentration of CD4+ T infected cells present at each time step. The effectiveness of the drugs and the infected cell concentration at the beginning of treatment are the control parameters of the cell population’s dynamics during therapy. The model allows describing processes of mono and combined therapies. The dynamics that emerges from this model when considering combined antiretroviral therapies reproduces with fair qualitative agreement the phases and different time scales of the process. As observed in clinical data, the results reproduce the significant decrease in the population of infected cells and a concomitant increase of the population of healthy cells in a short timescale (weeks) after the initiation of treatment. Over long time scales, early treatment with potent drugs may lead to undetectable levels of infection. For late treatment or treatments starting with a low density of CD4+ T healthy cells it was observed that the treatment may lead to a steady state in which the T cell counts are above the threshold associated with the onset of AIDS. The results obtained are validated through comparison to available clinical trial data.

  7. N-terminal modifications of cellular proteins: The enzymes involved, their substrate specificities and biological effects

    Science.gov (United States)

    Varland, Sylvia; Osberg, Camilla; Arnesen, Thomas

    2015-01-01

    The vast majority of eukaryotic proteins are N-terminally modified by one or more processing enzymes. Enzymes acting on the very first amino acid of a polypeptide include different peptidases, transferases, and ligases. Methionine aminopeptidases excise the initiator methionine leaving the nascent polypeptide with a newly exposed amino acid that may be further modified. N-terminal acetyl-, methyl-, myristoyl-, and palmitoyltransferases may attach an acetyl, methyl, myristoyl, or palmitoyl group, respectively, to the α-amino group of the target protein N-terminus. With the action of ubiquitin ligases, one or several ubiquitin molecules are transferred, and hence, constitute the N-terminal modification. Modifications at protein N-termini represent an important contribution to proteomic diversity and complexity, and are essential for protein regulation and cellular signaling. Consequently, dysregulation of the N-terminal modifying enzymes is implicated in human diseases. We here review the different protein N-terminal modifications occurring co- or post-translationally with emphasis on the responsible enzymes and their substrate specificities. PMID:25914051

  8. Improved specificity of in vitro anti-HIV antibody production: implications for diagnosis and timing of transmission in infants born to HIV-seropositive mothers.

    Science.gov (United States)

    Wang, X P; Paul, M; Tetali, S; Abrams, E; Bamji, M; Gulick, L; Chirmule, N; Oyaizu, N; Bakshi, S; Pahwa, S

    1994-06-01

    In vitro anti-HIV antibody production (IVAP), initially introduced as a method for diagnosis of human immunodeficiency virus type 1 (HIV-1) infection in infants, has been limited in its application because of poor specificity and sensitivity early in life. The aims of this study were to improve the specificity of the IVAP assay and to evaluate its sensitivity in conjunction with assays of HIV culture, polymerase chain reaction (PCR), and p24 antigen. To prevent false-positive reactions resulting from maternal serum-derived cytophilic anti-HIV IgG, additional preculture and washing steps for peripheral blood mononuclear cells (PBMCs) were introduced that resulted in dramatic improvement in specificity of IVAP. The sensitivity of the revised IVAP at age < 3 months in 20 infected infants was, however, only 25%; of 15 infected infants initially negative in IVAP, 13 became positive at a mean estimated age of 4.4 +/- 1.8 months. When correlated with virological assays, a failure to respond in IVAP at age < 1 month was often associated with negative virological identification, whereas a positive IVAP response at age < 3 months was always associated with positive results in all virological assays. Moreover, conversion from negative IVAP to positive responses occurred subsequent to, and not concurrently with, a positive virological identification of infected infants. The revised IVAP methodology renders this assay potentially useful as an additional tool not only for the diagnosis of HIV infection, but for estimating timing of maternal-infant HIV transmission as well.

  9. HIV specific responses induced in nonhuman primates with ANRS HIV-Lipo-5 vaccine combined with rMVA-HIV prime or boost immunizations.

    Science.gov (United States)

    Dereuddre-Bosquet, Nathalie; Baron, Marie-Laurence; Contreras, Vanessa; Gosse, Leslie; Mangeot, Isabelle; Martinon, Frédéric; Yousfi, Rahima; Clayette, Pascal; Levy, Yves; Le Grand, Roger

    2015-05-11

    We evaluated the immunogenicity of a prime/boost vaccine strategy combining 5 lipopeptides (HIV-Lipo-5) and a recombinant modified vaccinia virus Ankara (rMVA-HIV) in cynomolgus macaques. Both of these vaccine components deliver HIV LAI Gag, Pol, and Nef antigens. Systemic and local safety was excellent in all groups. Immunization with HIV-Lipo-5 alone induced significant serum anti-HIV antibody titers which were not modified by rMVA-HIV immunization. However, induction of T-cell responses, as measured by IFNγ and IL-2 producing cells upon short-term stimulation with HIV peptide pools, required combined immunization with rMVA-HIV. Responses were preferentially observed against Gag antigen. Interestingly, HIV-Lipo-5 efficiently primed HIV induced T-cell responses upon the injection of rMVA-HIV, which may help to reduce the required number of vector injections. Our results provide a rationale for the use of a strategy involving HIV-Lipo-5 priming followed by rMVA-HIV booster immunization as a prophylactic or therapeutic vaccine approach against HIV infection and AIDS. Copyright © 2015 Elsevier Ltd. All rights reserved.

  10. Analysis of HIV-1- and CMV-specific memory CD4 T-cell responses during primary and chronic infection.

    Science.gov (United States)

    Harari, Alexandre; Rizzardi, G Paolo; Ellefsen, Kim; Ciuffreda, Donatella; Champagne, Patrick; Bart, Pierre-Alexandre; Kaufmann, Daniel; Telenti, Amalio; Sahli, Roland; Tambussi, Giuseppe; Kaiser, Laurent; Lazzarin, Adriano; Perrin, Luc; Pantaleo, Giuseppe

    2002-08-15

    CD4 T-cell-specific memory antiviral responses to human immunodeficiency virus type 1 (HIV-1) and cytomegalovirus (CMV) were investigated in 16 patients with documented primary HIV-1 infection (4 of the 16 subjects also had primary CMV infection) and compared with those observed in patients with chronic HIV-1 and CMV coinfection. Virus-specific memory CD4 T cells were characterized on the basis of the expression of the chemokine receptor CCR7. HIV-1- and CMV-specific interferon-gamma-secreting CD4 T cells were detected in patients with primary and chronic HIV-1 and CMV coinfection and were mostly contained in the cell population lacking expression of CCR7. The magnitude of the primary CMV-specific CD4 T-cell response was significantly greater than that of chronic CMV infection, whereas there were no differences between primary and chronic HIV-1-specific CD4 T-cell responses. A substantial proportion of CD4(+)CCR7(-) T cells were infected with HIV-1. These results advance the characterization of antiviral memory CD4 T-cell response and the delineation of the potential mechanisms that likely prevent the generation of a robust CD4 T-cell immune response during primary infection.

  11. Fc Receptor-Mediated Activities of Env-Specific Human Monoclonal Antibodies Generated from Volunteers Receiving the DNA Prime-Protein Boost HIV Vaccine DP6-001.

    Science.gov (United States)

    Costa, Matthew R; Pollara, Justin; Edwards, Regina Whitney; Seaman, Michael S; Gorny, Miroslaw K; Montefiori, David C; Liao, Hua-Xin; Ferrari, Guido; Lu, Shan; Wang, Shixia

    2016-11-15

    HIV-1 is able to elicit broadly potent neutralizing antibodies in a very small subset of individuals only after several years of infection, and therefore, vaccines that elicit these types of antibodies have been difficult to design. The RV144 trial showed that moderate protection is possible and that this protection may correlate with antibody-dependent cellular cytotoxicity (ADCC) activity. Our previous studies demonstrated that in an HIV vaccine phase I trial, the DP6-001 trial, a polyvalent Env DNA prime-protein boost formulation could elicit potent and broadly reactive, gp120-specific antibodies with positive neutralization activities. Here we report on the production and analysis of HIV-1 Env-specific human monoclonal antibodies (hMAbs) isolated from vaccinees in the DP6-001 trial. For this initial report, 13 hMAbs from four vaccinees in the DP6-001 trial showed broad binding to gp120 proteins of diverse subtypes both autologous and heterologous to vaccine immunogens. Equally cross-reactive Fc receptor-mediated functional activities, including ADCC and antibody-dependent cellular phagocytosis (ADCP) activities, were present with both immune sera and isolated MAbs, confirming the induction of nonneutralizing functional hMAbs by the DNA prime-protein boost vaccination. Elicitation of broadly reactive hMAbs by vaccination in healthy human volunteers confirms the value of the polyvalent formulation in this HIV vaccine design. The roles of Fc receptor-mediated protective antibody responses are gaining more attention due to their potential contribution to the low-level protection against HIV-1 infection that they provided in the RV144 trial. At the same time, information about hMabs from other human HIV vaccine studies is very limited. In the current study, both immune sera and monoclonal antibodies from vaccinated humans showed not only high-level ADCC and ADCP activities but also cross-subtype ADCC and ADCP activities when a polyvalent DNA prime-protein boost

  12. Alterations in cellular pharmacokinetics and pharmacodynamics of elvitegravir in response to ethanol exposure in HIV-1 infected monocytic (U1) cells

    Science.gov (United States)

    Midde, Narasimha M.; Sinha, Namita; Lukka, Pradeep B.; Meibohm, Bernd

    2017-01-01

    Ethanol consumption is negatively associated with antiretroviral therapy (ART) adherence and general health in HIV positive individuals. Previously, we demonstrated ethanol-mediated alterations to metabolism of elvitegravir (EVG) in human liver microsomes. In the current study, we investigated ethanol influence on the pharmacokinetic and pharmacodynamic interactions of EVG in HIV infected monocytic (U1) cells. U1 cells were treated with 5 μM EVG, 2 μM Cobicistat (COBI), a booster drug, and 20 mM ethanol for up to 24 hours. EVG, HIV p24 levels, alterations in cytochrome P450 (CYP) 3A4, MRP1, and MDR1 protein expressions were measured. Presence of ethanol demonstrated a significant effect on the total exposures of both EVG and EVG in combination with COBI. Ethanol also increased the HIV replication despite the presence of drugs and this elevated HIV replication was reduced in the presence of MRP1 and MDR1 inhibitors. Consequently, a slight increase in EVG concentration was observed in the presence of MRP1 inhibitor but not with MDR1 inhibitor. Furthermore, CYP3A4, MRP1 and MDR1 protein levels were significantly induced in treatment groups which included ethanol compared to those with no treatment. In summary, these findings suggest that Ethanol reduces intra cellular EVG exposure by modifying drug metabolism and transporter protein expression. This study provides valuable evidence for further investigation of ethanol effects on the intracellular concentration of EVG in ex vivo or in vivo studies. PMID:28231276

  13. Insights into the broad cellular effects of nelfinavir and the HIV protease inhibitors supporting their role in cancer treatment and prevention.

    Science.gov (United States)

    Gantt, Soren; Casper, Corey; Ambinder, Richard F

    2013-09-01

    The development of HIV protease inhibitors more than two decades ago heralded a new era in HIV care, changing the infection from universally fatal to chronic but controllable. With the widespread use of protease inhibitors, there was a reduction in the incidence and mortality of HIV-associated malignancies. Studies later found these drugs to have promising direct antitumor effects. Protease inhibitors have a wide range of effects on several cellular pathways that are important for tumorigenesis and independent of inhibition of the HIV protease, including reducing angiogenesis and cell invasion, inhibition of the Akt pathway, induction of autophagy, and promotion of apoptosis. Among protease inhibitors, nelfinavir appears to have the most potent and broad antineoplastic activities, and also affects replication of the oncogenic herpesviruses Kaposi sarcoma-associated herpesvirus and Epstein-Barr virus. Nelfinavir is being studied for the prevention and treatment of a wide range of malignancies in persons with and without HIV infection. Nelfinavir and other protease inhibitors are well tolerated, oral drugs that have promising antitumor properties, and may prove to play an important role in the prevention and treatment of several cancers. Additional insights into protease inhibitors' mechanisms of action may lead to the development of novel cancer chemotherapy agents.

  14. Toward the discovery of novel anti-HIV drugs. Second-generation inhibitors of the cellular ATPase DDX3 with improved anti-HIV activity: synthesis, structure-activity relationship analysis, cytotoxicity studies, and target validation.

    Science.gov (United States)

    Maga, Giovanni; Falchi, Federico; Radi, Marco; Botta, Lorenzo; Casaluce, Gianni; Bernardini, Martina; Irannejad, Hamid; Manetti, Fabrizio; Garbelli, Anna; Samuele, Alberta; Zanoli, Samantha; Esté, José A; Gonzalez, Emmanuel; Zucca, Elisa; Paolucci, Stefania; Baldanti, Fausto; De Rijck, Jan; Debyser, Zeger; Botta, Maurizio

    2011-08-01

    A hit optimization protocol applied to the first nonnucleoside inhibitor of the ATPase activity of human DEAD-box RNA helicase DDX3 led to the design and synthesis of second-generation rhodanine derivatives with better inhibitory activity toward cellular DDX3 and HIV-1 replication. Additional DDX3 inhibitors were identified among triazine compounds. Biological data were rationalized in terms of structure-activity relationships and docking simulations. Antiviral activity and cytotoxicity of selected DDX3 inhibitors are reported and discussed. A thorough analysis confirmed human DDX3 as a valid anti-HIV target. The compounds described herein represent a significant advance in the pursuit of novel drugs that target HIV-1 host cofactors.

  15. Prevalence and Gene Characteristics of Antibodies with Cofactor-induced HIV-1 Specificity*

    Science.gov (United States)

    Lecerf, Maxime; Scheel, Tobias; Pashov, Anastas D.; Jarossay, Annaelle; Ohayon, Delphine; Planchais, Cyril; Mesnage, Stephane; Berek, Claudia; Kaveri, Srinivas V.; Lacroix-Desmazes, Sébastien; Dimitrov, Jordan D.

    2015-01-01

    The healthy immune repertoire contains a fraction of antibodies that bind to various biologically relevant cofactors, including heme. Interaction of heme with some antibodies results in induction of new antigen binding specificities and acquisition of binding polyreactivity. In vivo, extracellular heme is released as a result of hemolysis or tissue damage; hence the post-translational acquisition of novel antigen specificities might play an important role in the diversification of the immunoglobulin repertoire and host defense. Here, we demonstrate that seronegative immune repertoires contain antibodies that gain reactivity to HIV-1 gp120 upon exposure to heme. Furthermore, a panel of human recombinant antibodies was cloned from different B cell subpopulations, and the prevalence of antibodies with cofactor-induced specificity for gp120 was determined. Our data reveal that upon exposure to heme, ∼24% of antibodies acquired binding specificity for divergent strains of HIV-1 gp120. Sequence analyses reveal that heme-sensitive antibodies do not differ in their repertoire of variable region genes and in most of the molecular features of their antigen-binding sites from antibodies that do not change their antigen binding specificity. However, antibodies with cofactor-induced gp120 specificity possess significantly lower numbers of somatic mutations in their variable region genes. This study contributes to the understanding of the significance of cofactor-binding antibodies in immunoglobulin repertoires and of the influence that the tissue microenvironment might have in shaping adaptive immune responses. PMID:25564611

  16. Factors associated with specific causes of death amongst HIV-positive individuals in the D:A:D Study

    DEFF Research Database (Denmark)

    Smith, Colette; Sabin, Caroline A; Lundgren, Jens D;

    2010-01-01

    To investigate any emerging trends in causes of death amongst HIV-positive individuals in the current cART era, and to investigate the factors associated with each specific cause of death.......To investigate any emerging trends in causes of death amongst HIV-positive individuals in the current cART era, and to investigate the factors associated with each specific cause of death....

  17. Specific psychiatric correlates of acute care utilization among unstably housed HIV-positive adults.

    Science.gov (United States)

    Chartier, Maggie; Carrico, Adam W; Weiser, Sheri D; Kushel, Margot B; Riley, Elise D

    2012-01-01

    The role of specific psychiatric diagnoses in emergency department use and/or inpatient hospitalizations (acute care) has not been extensively examined among HIV-infected, unstably housed persons. A community-recruited sample of 284 HIV-infected, unstably housed adults completed the Diagnostic Interview Schedule for DSM-IV. One-third of participants screened positive for major depression and stimulant use disorders. Sleeping on the street [adjusted odds ratio (AOR) = 4.21], major depression (AOR = 2.88) and stimulant use disorders (AOR = 4.45) were associated with greater odds of acute care use. Housing and effective treatment of depression and stimulant use disorders may decrease use of acute care services in this population.

  18. Efficacy of peptide nucleic acid and selected conjugates against specific cellular pathologies of amyotrophic lateral sclerosis.

    Science.gov (United States)

    Browne, Elisse C; Parakh, Sonam; Duncan, Luke F; Langford, Steven J; Atkin, Julie D; Abbott, Belinda M

    2016-04-01

    Cellular studies have been undertaken on a nonamer peptide nucleic acid (PNA) sequence, which binds to mRNA encoding superoxide dismutase 1, and a series of peptide nucleic acids conjugated to synthetic lipophilic vitamin analogs including a recently prepared menadione (vitamin K) analog. Reduction of both mutant superoxide dismutase 1 inclusion formation and endoplasmic reticulum stress, two of the key cellular pathological hallmarks in amyotrophic lateral sclerosis, by two of the prepared PNA oligomers is reported for the first time.

  19. Cellular antisense activity of peptide nucleic acid (PNAs) targeted to HIV-1 polypurine tract (PPT) containing RNA.

    Science.gov (United States)

    Boutimah-Hamoudi, Fatima; Leforestier, Erwan; Sénamaud-Beaufort, Catherine; Nielsen, Peter E; Giovannangeli, Carine; Saison-Behmoaras, Tula Ester

    2007-01-01

    DNA and RNA oligomers that contain stretches of guanines can associate to form stable secondary structures including G-quadruplexes. Our study shows that the (UUAAAAGAAAAGGGGGGAU) RNA sequence, from the human immunodeficiency virus type 1 (HIV-1 polypurine tract or PPT sequence) forms in vitro a stable folded structure involving the G-run. We have investigated the ability of pyrimidine peptide nucleic acid (PNA) oligomers targeted to the PPT sequence to invade the folded RNA and exhibit biological activity at the translation level in vitro and in cells. We find that PNAs can form stable complexes even with the structured PPT RNA target at neutral pH. We show that T-rich PNAs, namely the tridecamer-I PNA (C4T4CT4) forms triplex structures whereas the C-rich tridecamer-II PNA (TC6T4CT) likely forms a duplex with the target RNA. Interestingly, we find that both C-rich and T-rich PNAs arrested in vitro translation elongation specifically at the PPT target site. Finally, we show that T-rich and C-rich tridecamer PNAs that have been identified as efficient and specific blockers of translation elongation in vitro, specifically inhibit translation in streptolysin-O permeabilized cells where the PPT target sequence has been introduced upstream the reporter luciferase gene.

  20. The nucleocapsid region of HIV-1 Gag cooperates with the PTAP and LYPXnL late domains to recruit the cellular machinery necessary for viral budding.

    Directory of Open Access Journals (Sweden)

    Vincent Dussupt

    2009-03-01

    Full Text Available HIV-1 release is mediated through two motifs in the p6 region of Gag, PTAP and LYPX(nL, which recruit cellular proteins Tsg101 and Alix, respectively. The Nucleocapsid region of Gag (NC, which binds the Bro1 domain of Alix, also plays an important role in HIV-1 release, but the underlying mechanism remains unclear. Here we show that the first 202 residues of the Bro1 domain (Bro(i are sufficient to bind Gag. Bro(i interferes with HIV-1 release in an NC-dependent manner and arrests viral budding at the plasma membrane. Similar interrupted budding structures are seen following over-expression of a fragment containing Bro1 with the adjacent V domain (Bro1-V. Although only Bro1-V contains binding determinants for CHMP4, both Bro(i and Bro1-V inhibited release via both the PTAP/Tsg101 and the LYPX(nL/Alix pathways, suggesting that they interfere with a key step in HIV-1 release. Remarkably, we found that over-expression of Bro1 rescued the release of HIV-1 lacking both L domains. This rescue required the N-terminal region of the NC domain in Gag and the CHMP4 binding site in Bro1. Interestingly, release defects due to mutations in NC that prevented Bro1 mediated rescue of virus egress were rescued by providing a link to the ESCRT machinery via Nedd4.2s over-expression. Our data support a model in which NC cooperates with PTAP in the recruitment of cellular proteins necessary for its L domain activity and binds the Bro1-CHMP4 complex required for LYPX(nL-mediated budding.

  1. HIV-Specific CD8+ T Cell-Mediated Viral Suppression Correlates With the Expression of CD57

    DEFF Research Database (Denmark)

    Jensen, Sanne S; Tingstedt, Jeanette Linnea; Larsen, Tine Kochendorf

    2016-01-01

    BACKGROUND: Virus-specific CD8(+) T-cell responses are believed to play an important role in the control of HIV-1 infection; however, what constitutes an effective HIV-1 CD8(+) T-cell response remains a topic of debate. The ex vivo viral suppressive capacity was measured of CD8(+) T cells from 44....... METHOD: Ex vivo suppression assay was used to evaluate the ability of CD8(+) T cells to suppress HIV-1 replication in autologous CD4(+) T cells. The CD107a, interferon-γ, interleukin-2, tumor necrosis factor-α (TNF-α), and macrophage inflammatory protein-1β (MIP-1β) responses to HIV-1 were evaluated...... significantly higher in individuals with ex vivo suppressive activity compared with individuals without suppressive activity. CONCLUSIONS: Standard in vitro assays measuring one or several cytokines do not correlate with the functional viral suppressive capacity of CD8(+) T cells from HIV-1-positive individuals...

  2. A novel class of anti-HIV agents with multiple copies of enfuvirtide enhances inhibition of viral replication and cellular transmission in vitro.

    Directory of Open Access Journals (Sweden)

    Chien-Hsing Chang

    Full Text Available We constructed novel HIV-1 fusion inhibitors that may overcome the current limitations of enfuvirtide, the first such therapeutic in this class. The three prototypes generated by the Dock-and-Lock (DNL technology to comprise four copies of enfuvirtide tethered site-specifically to the Fc end of different humanized monoclonal antibodies potently neutralize primary isolates (both R5-tropic and X4-tropic, as well as T-cell-adapted strains of HIV-1 in vitro. All three prototypes show EC(50 values in the subnanomolar range, which are 10- to 100-fold lower than enfuvirtide and attainable whether or not the constitutive antibody targets HIV-1. The potential of such conjugates to purge latently infected cells was also demonstrated in a cell-to-cell viral inhibition assay by measuring their efficacy to inhibit the spread of HIV-1(LAI from infected human peripheral blood mononuclear cells to Jurkat T cells over a period of 30 days following viral activation with 100 nM SAHA (suberoylanilide hydroxamic acid. The IgG-like half-life was not significantly different from that of the parental antibody, as shown by the mean serum concentration of one prototype in mice at 72 h. These encouraging results provide a rationale to develop further novel anti-HIV agents by coupling additional antibodies of interest with alternative HIV-inhibitors via recombinantly-produced, self-assembling, modules.

  3. A cellular protein specifically binds to the 3'-terminal sequences of hepatitis C virus intermediate negative-strand RNA

    Institute of Scientific and Technical Information of China (English)

    王巍; 邓庆丽; 黄开红; 段朝晖; 邵静; 黄志清; 黄志明

    2003-01-01

    ObjectiveTo study the mechanism of the cellular proteins involved in the process of replication of hepatitis C virus (HCV) negative-strand RNA.MethodsUltraviolet (UV) cross-linking was used to identify the cellular proteins that would bind to the 3'-end of HCV negative-strand RNA. Competition experimentwas used to confirm the specificity of this binding, in which excess nonhomologous protein and RNA transcripts were used as competitors. The required binding sequence was determined by mapping, then the binding site was predicted through secondary structure analysis.ResultsA cellular protein of 45 kD (p45) was found to bind specifically to the 3'-endof HCV negative-strand RNA by UV cross-linking. nhomologous proteins and RNA transcripts could not compete out this binding, whereas the unlabeled 3'-endof HCV negative-strand RNA could. Mapping of the protein-binding site suggested that the 3'-end 131-278nt of HCV negative-strand RNA was the possible protein-binding region. Analysis of RNA secondary structure presumed that the potential binding site was located at 194-GAAAGAAC-201. ConclusionThe cellular protein p45 could specifically bind to the secondary structure of the 3'-end of HCV intermediate negative-strand RNA, and may play an important role in HCV RNA replication.

  4. Association between Nef-specific CD8 T-cell responses and disease progression in HIV-1 subtype B infection

    Institute of Scientific and Technical Information of China (English)

    JIAO Yang; LI Tai-sheng; XIE Jing; HAN Yang; QIU Zhi-feng; ZUO Ling-yan; Thomas Mourez; WANG Ai-xia

    2006-01-01

    Background The correlation between HIV-1 Nef-specific CD8 T-cell responses and markers of HIV-1 disease progression still remains unclear. This study analysed and compared the role of HIV-1 Nef-specific CD8 T-cell responses in patients with different disease status.Methods Two groups of patients with HIV-1 subtype B infection were selected according to CD4 count and clinical manifestations: long-term nonprogresssors (LTNPs, n = 20) and advanced progressors (Aps, CD4 count <500 cells/μ1, n = 34). Nef-specific CD8 T-cell responses were studied by interferon- γ ELISpot assay against 3 pools of HIV-Nef peptides.Results Nef-specific CD8 T-cell responses did not correlate with viral load or CD4 count in all patients and no significant differences were found in the magnitude of Nef-specific CD8 T-cell responses between groups LTNPs and Aps (670 SFC/106 peripheral blood mononuclear cells vs 1107 SFC/106 peripheral blood mononuclear cells,P = 0.255). Further comparisons showed that there were also no significant correlations observed in group LTNPs,but Nef-specific CD8 T cells correlated negatively with viral load (r = -0.397, P = 0.020) and positively with CD4 count (r = 0.364, P = 0.034) in group Aps.Conclusion These data suggest that different correlation patterns between Nef-specific CD8 T-cell responses and disease progression exist in LTNPs and Aps. Although a negative association was observed with concurrent plasma HIV RNA in Aps, Nef-specific CD8 T-cell responses might fail to play a protective role in different stages of HIV- 1 infection.

  5. Specific Destruction of HIV Proviral p17 Gene in T Lymphoid Cells Achieved by the Genome Editing Technology.

    Science.gov (United States)

    Kishida, Tsunao; Ejima, Akika; Mazda, Osam

    2016-01-01

    Recent development in genome editing technologies has enabled site-directed deprivation of a nucleotide sequence in the chromosome in mammalian cells. Human immunodeficiency (HIV) infection causes integration of proviral DNA into the chromosome, which potentially leads to re-emergence of the virus, but conventional treatment cannot delete the proviral DNA sequence from the cells infected with HIV. In the present study, the transcription activator-like effector nucleases (TALENs) specific for the HIV p17 gene were constructed, and their activities to destroy the target sequence were evaluated. SSA assay showed a high activity of a pair of p17-specific TALENs. A human T lymphoid cell line, Jurkat, was infected with a lentivirus vector followed by transfection with the TALEN-HIV by electroporation. The target sequence was destructed in approximately 10-95% of the p17 polymerase chain reaction clones, and the efficiencies depended on the Jurkat-HIV clones. Because p17 plays essential roles for assembly and budding of HIV, and this gene has relatively low nucleotide sequence diversity, genome editing procedures targeting p17 may provide a therapeutic benefit for HIV infection.

  6. Decreased HIV-specific T-regulatory responses are associated with effective DC-vaccine induced immunity.

    Directory of Open Access Journals (Sweden)

    Vedran Brezar

    2015-03-01

    Full Text Available The role of regulatory T cells (Tregs in vaccination has been poorly investigated. We have reported that vaccination with ex vivo-generated dendritic-cells (DC loaded with HIV-lipopeptides (LIPO-5-DC vaccine in HIV-infected patients was well tolerated and highly immunogenic. These responses and their relation to viral replication following analytical treatment interruption (ATI were variable. Here, we investigated whether the presence of HIV-specific Tregs might explain these differences. Co-expression of CD25, CD134, CD39 and FoxP3 was used to delineate both antigen-specific Tregs and effectors T cells (Teffs. Median LIPO-5 specific-CD25+CD134+ polyfunctional T cells increased from 0.1% (IQR 0-0.3 before vaccination (week -4 to 2.1% (IQR 1.1-3.9 at week 16 following 4 immunizations (p=0.001 and were inversely correlated with maximum viral load following ATI (r=-0.77, p=0.001. Vaccinees who displayed lower levels of HIV-specific CD4+CD134+CD25+CD39+FoxP3+ Tregs responded better to the LIPO-5-DC vaccine. After vaccination, the frequency of HIV-specific Tregs decreased (from 69.3 at week -4 to 31.7% at week 16 and inversely correlated with HIV-specific IFN-γ-producing cells (r=-0.64, p=0.002. We show that therapeutic immunization skewed the HIV-specific response from regulatory to effector phenotype which impacts on the magnitude of viral replication following ATI.

  7. Impaired hepatitis C virus-specific T cell responses and recurrent hepatitis C virus in HIV coinfection.

    Directory of Open Access Journals (Sweden)

    Arthur Y Kim

    2006-12-01

    Full Text Available Hepatitis C virus (HCV-specific T cell responses are critical for spontaneous resolution of HCV viremia. Here we examined the effect of a lymphotropic virus, HIV-1, on the ability of coinfected patients to maintain spontaneous control of HCV infection.We measured T cell responsiveness by lymphoproliferation and interferon-gamma ELISPOT in a large cohort of HCV-infected individuals with and without HIV infection. Among 47 HCV/HIV-1-coinfected individuals, spontaneous control of HCV was associated with more frequent HCV-specific lymphoproliferative (LP responses (35% compared to coinfected persons who exhibited chronic HCV viremia (7%, p = 0.016, but less frequent compared to HCV controllers who were not HIV infected (86%, p = 0.003. Preservation of HCV-specific LP responses in coinfected individuals was associated with a higher nadir CD4 count (r(2 = 0.45, p < 0.001 and the presence and magnitude of the HCV-specific CD8(+ T cell interferon-gamma response (p = 0.0014. During long-term follow-up, recurrence of HCV viremia occurred in six of 25 coinfected individuals with prior control of HCV, but in 0 of 16 HIV-1-negative HCV controllers (p = 0.03, log rank test. In these six individuals with recurrent HCV viremia, the magnitude of HCV viremia following recurrence inversely correlated with the CD4 count at time of breakthrough (r = -0.94, p = 0.017.These results indicate that HIV infection impairs the immune response to HCV-including in persons who have cleared HCV infection-and that HIV-1-infected individuals with spontaneous control of HCV remain at significant risk for a second episode of HCV viremia. These findings highlight the need for repeat viral RNA testing of apparent controllers of HCV infection in the setting of HIV-1 coinfection and provide a possible explanation for the higher rate of HCV persistence observed in this population.

  8. A Bayesian hierarchical model with novel prior specifications for estimating HIV testing rates

    Science.gov (United States)

    An, Qian; Kang, Jian; Song, Ruiguang; Hall, H. Irene

    2016-01-01

    Human immunodeficiency virus (HIV) infection is a severe infectious disease actively spreading globally, and acquired immunodeficiency syndrome (AIDS) is an advanced stage of HIV infection. The HIV testing rate, that is, the probability that an AIDS-free HIV infected person seeks a test for HIV during a particular time interval, given no previous positive test has been obtained prior to the start of the time, is an important parameter for public health. In this paper, we propose a Bayesian hierarchical model with two levels of hierarchy to estimate the HIV testing rate using annual AIDS and AIDS-free HIV diagnoses data. At level one, we model the latent number of HIV infections for each year using a Poisson distribution with the intensity parameter representing the HIV incidence rate. At level two, the annual numbers of AIDS and AIDS-free HIV diagnosed cases and all undiagnosed cases stratified by the HIV infections at different years are modeled using a multinomial distribution with parameters including the HIV testing rate. We propose a new class of priors for the HIV incidence rate and HIV testing rate taking into account the temporal dependence of these parameters to improve the estimation accuracy. We develop an efficient posterior computation algorithm based on the adaptive rejection metropolis sampling technique. We demonstrate our model using simulation studies and the analysis of the national HIV surveillance data in the USA. PMID:26567891

  9. Do HIV-specific CTL continue to have an antiviral function during antiretroviral therapy? If not, why not, and what can be done about it?

    OpenAIRE

    Dorian eMcIlroy

    2013-01-01

    Pharmacological re-activation of HIV expression from latent proviruses coupled with fully suppressive anti-retroviral therapy (ART) has been suggested as a strategy to eradicate HIV infection. In order for this strategy to be effective, latently infected cells must be killed either by the cytopathic effect of reactivated HIV gene expression, or by HIV-specific CTL. However, a review of current data reveals little evidence that CTL retain an anti-viral effector capacity in patients on fully su...

  10. Correlation of HIV-specific immunity, viral control, and diversification following planned multiple exposures to autologous HIV in a pediatric population.

    Science.gov (United States)

    Borkowsky, William; McFarland, Elizabeth J; Yogev, Ram; Li, Yonghua; Harding, Paul

    2011-10-01

    Repeated controlled exposure to autologous virus was previously shown to result in increased CD8 T lymphocyte response to HIV antigens and accompanying reduction in viremia. We attempted to see if this immunity contributed to virologic control by correlating the immune response with quasispecies envelope diversification, an indicator of immune selection. The greatest diversification was seen in those with the greatest reduction in viremia but was unrelated to the frequency of Env-specific gamma interferon-producing cells. There was a trend toward correlation between the response to multiple HIV antigens and diversification.

  11. Microplate-based assay for identifying small molecules that bind a specific intersubunit interface within the assembled HIV-1 capsid.

    Science.gov (United States)

    Halambage, Upul D; Wong, Jason P; Melancon, Bruce J; Lindsley, Craig W; Aiken, Christopher

    2015-09-01

    Despite the availability of >30 effective drugs for managing HIV-1 infection, no current therapy is curative, and long-term management is challenging owing to the emergence and spread of drug-resistant mutants. Identification of drugs against novel HIV-1 targets would expand the current treatment options and help to control resistance. The highly conserved HIV-1 capsid protein represents an attractive target because of its multiple roles in replication of the virus. However, the low antiviral potencies of the reported HIV-1 capsid-targeting inhibitors render them unattractive for therapeutic development. To facilitate the identification of more-potent HIV-1 capsid inhibitors, we developed a scintillation proximity assay to screen for small molecules that target a biologically active and specific intersubunit interface in the HIV-1 capsid. The assay, which is based on competitive displacement of a known capsid-binding small-molecule inhibitor, exhibited a signal-to-noise ratio of >9 and a Z factor of >0.8. In a pilot screen of a chemical library containing 2,400 druglike compounds, we obtained a hit rate of 1.8%. This assay has properties that are suitable for screening large compound libraries to identify novel HIV-1 capsid ligands with antiviral activity.

  12. Do HIV-specific CTL continue to have an antiviral function during antiretroviral therapy? If not, why not, and what can be done about it?

    Directory of Open Access Journals (Sweden)

    Dorian eMcIlroy

    2013-03-01

    Full Text Available Pharmacological re-activation of HIV expression from latent proviruses coupled with fully suppressive anti-retroviral therapy (ART has been suggested as a strategy to eradicate HIV infection. In order for this strategy to be effective, latently infected cells must be killed either by the cytopathic effect of reactivated HIV gene expression, or by HIV-specific CTL. However, a review of current data reveals little evidence that CTL retain an anti-viral effector capacity in patients on fully suppressive ART, implying that the HIV-specific CTL present in these patients will not be able to eliminate HIV-infected CD4+ T-cells effectively. If this is due to functional impairment or a quantitative deficit of HIV-specific CTL during ART, then therapeutic vaccination may improve the prospects for eradicating latent reservoirs. However, data from the macaque SIV model indicate that in vivo, SIV-specific CTL are only effective during the early stages of the viral replication cycle, and this constitutes an alternative explanation why HIV-specific CTL do not appear to have an impact on HIV reservoirs during ART. In that case, immunotoxins that target HIV-expressing cells may be a more promising approach for HIV eradication.

  13. Neutralizing Antibody Response and Antibody-Dependent Cellular Cytotoxicity in HIV-1-Infected Individuals from Guinea-Bissau and Denmark

    DEFF Research Database (Denmark)

    Borggren, Marie; Jensen, Sanne Skov; Heyndrickx, Leo

    2016-01-01

    cytotoxicity (ADCC) against local and nonlocal circulating HIV-1 strains. The neutralizing activity did not demonstrate higher potential against local circulating strains according to geography and subtype determination, but the plasma from Danish individuals demonstrated significantly higher inhibitory...

  14. Cellular Activation and Intracellular HCV Load in Peripheral Blood Monocytes Isolated from HCV Monoinfected and HIV-HCV Coinfected Patients

    OpenAIRE

    Isabelle Dichamp; Wasim Abbas; Amit Kumar; Vincent Di Martino; Georges Herbein

    2014-01-01

    BACKGROUND: During HCV infection, the activation status of peripheral blood monocytes and its impact on HCV replication are poorly understood. We hypothesized that a modified activation of peripheral blood monocytes in HIV-HCV coinfected compared to HCV monoinfected patients may contribute to different monocytes reservoirs of HCV replication. METHODS: We performed a case-control analysis involving HCV-infected patients with and without HIV coinfection. In peripheral blood mononuclear cells (P...

  15. Lymphocytic alveolitis is associated with the accumulation of functionally impaired HIV-specific T cells in the lung of antiretroviral therapy-naive subjects.

    Science.gov (United States)

    Neff, C Preston; Chain, Jennifer L; MaWhinney, Samantha; Martin, Allison K; Linderman, Derek J; Flores, Sonia C; Campbell, Thomas B; Palmer, Brent E; Fontenot, Andrew P

    2015-02-15

    Lymphocytic alveolitis in HIV-1-infected individuals is associated with multiple pulmonary complications and a poor prognosis. Although lymphocytic alveolitis has been associated with viremia and an increased number of CD8(+) T cells in the lung, its exact cause is unknown. To determine if HIV-1-specific T cells are associated with lymphocytic alveolitis in HIV-1-infected individuals. Using blood and bronchoalveolar lavage (BAL) cells from normal control subjects and untreated HIV-1-infected individuals, we examined the frequency and functional capacity of HIV-1-specific T cells. We found that HIV-1-specific T cells were significantly elevated in the BAL compared with blood of HIV-1-infected individuals and strongly correlated with T-cell alveolitis. Expression of Ki67, a marker of in vivo proliferation, was significantly reduced on HIV-1-specific T cells in BAL compared with blood, suggesting a diminished proliferative capacity. In addition, HIV-1-specific CD4(+) and CD8(+) T cells in BAL had higher expression of programmed death 1 (PD-1) and lower cytotoxic T-lymphocyte antigen 4 (CTLA-4) expression than those in the blood. A strong correlation between PD-1, but not CTLA-4, and HIV-1-specific T-cell proliferation was seen, and blockade of the PD-1/PD-L1 pathway augmented HIV-1-specific T-cell proliferation, suggesting that the PD-1 pathway was the main cause of reduced proliferation in the lung. These findings suggest that alveolitis associated with HIV-1 infection is caused by the recruitment of HIV-1-specific CD4(+) and CD8(+) T cells to the lung. These antigen-specific T cells display an impaired proliferative capacity that is caused by increased expression of PD-1.

  16. Lymphocytic Alveolitis Is Associated with the Accumulation of Functionally Impaired HIV-Specific T Cells in the Lung of Antiretroviral Therapy–Naive Subjects

    Science.gov (United States)

    Neff, C. Preston; Chain, Jennifer L.; MaWhinney, Samantha; Martin, Allison K.; Linderman, Derek J.; Flores, Sonia C.; Campbell, Thomas B.; Fontenot, Andrew P.

    2015-01-01

    Rationale: Lymphocytic alveolitis in HIV-1–infected individuals is associated with multiple pulmonary complications and a poor prognosis. Although lymphocytic alveolitis has been associated with viremia and an increased number of CD8+ T cells in the lung, its exact cause is unknown. Objectives: To determine if HIV-1–specific T cells are associated with lymphocytic alveolitis in HIV-1–infected individuals. Methods: Using blood and bronchoalveolar lavage (BAL) cells from normal control subjects and untreated HIV-1–infected individuals, we examined the frequency and functional capacity of HIV-1–specific T cells. Measurements and Main Results: We found that HIV-1–specific T cells were significantly elevated in the BAL compared with blood of HIV-1–infected individuals and strongly correlated with T-cell alveolitis. Expression of Ki67, a marker of in vivo proliferation, was significantly reduced on HIV-1–specific T cells in BAL compared with blood, suggesting a diminished proliferative capacity. In addition, HIV-1–specific CD4+ and CD8+ T cells in BAL had higher expression of programmed death 1 (PD-1) and lower cytotoxic T-lymphocyte antigen 4 (CTLA-4) expression than those in the blood. A strong correlation between PD-1, but not CTLA-4, and HIV-1–specific T-cell proliferation was seen, and blockade of the PD-1/PD-L1 pathway augmented HIV-1–specific T-cell proliferation, suggesting that the PD-1 pathway was the main cause of reduced proliferation in the lung. Conclusions: These findings suggest that alveolitis associated with HIV-1 infection is caused by the recruitment of HIV-1–specific CD4+ and CD8+ T cells to the lung. These antigen-specific T cells display an impaired proliferative capacity that is caused by increased expression of PD-1. PMID:25536276

  17. Engineering HIV-resistant human CD4+ T cells with CXCR4-specific zinc-finger nucleases.

    Directory of Open Access Journals (Sweden)

    Craig B Wilen

    2011-04-01

    Full Text Available HIV-1 entry requires the cell surface expression of CD4 and either the CCR5 or CXCR4 coreceptors on host cells. Individuals homozygous for the ccr5Δ32 polymorphism do not express CCR5 and are protected from infection by CCR5-tropic (R5 virus strains. As an approach to inactivating CCR5, we introduced CCR5-specific zinc-finger nucleases into human CD4+ T cells prior to adoptive transfer, but the need to protect cells from virus strains that use CXCR4 (X4 in place of or in addition to CCR5 (R5X4 remains. Here we describe engineering a pair of zinc finger nucleases that, when introduced into human T cells, efficiently disrupt cxcr4 by cleavage and error-prone non-homologous DNA end-joining. The resulting cells proliferated normally and were resistant to infection by X4-tropic HIV-1 strains. CXCR4 could also be inactivated in ccr5Δ32 CD4+ T cells, and we show that such cells were resistant to all strains of HIV-1 tested. Loss of CXCR4 also provided protection from X4 HIV-1 in a humanized mouse model, though this protection was lost over time due to the emergence of R5-tropic viral mutants. These data suggest that CXCR4-specific ZFNs may prove useful in establishing resistance to CXCR4-tropic HIV for autologous transplant in HIV-infected individuals.

  18. Effects of vitamin D supplementation on the bone specific biomarkers in HIV infected individuals under treatment with efavirenz

    Directory of Open Access Journals (Sweden)

    Etminani-Esfahani Maryam

    2012-04-01

    Full Text Available Abstract Background It was reported that antiretroviral drugs such as efavirenz can increase the catabolism of vitamin D in HIV infected individuals. We have not found any study that evaluated effects of vitamin D supplementation on the bone specific biomarkers in HIV positive patients under treatment with antiretroviral regimen containing efavirenz. Findings Vitamin D deficiency was detected in 88.4 % of included patients. Baseline osteocalcin, but not collagen telopeptidase, serum levels were lower than normal range in all of these individuals. Both bone biomarkers’ concentrations increased significantly (p  Conclusion In the HIV-infected patients under treatment with efavirenz, vitamin D deficiency is prevalent. After supplementation with single dose of 300,000 IU vitamin D in this population, the activation of osteoblasts and osteoclasts stimulates bone formation and resorption respectively with favorable bone formation without any adverse event. Significant percent of HIV infected individuals are vitamin d deficient that could benefit from vitamin D supplementation.

  19. Overall and cause-specific mortality in HIV-positive subjects compared to the general population

    Directory of Open Access Journals (Sweden)

    Belen Alejos

    2014-11-01

    Full Text Available Introduction: Emerging non-AIDS related causes of death have been observed in HIV-positive subjects in industrialized countries. We aimed to analyze overall and cause-specific excess of mortality of HIV-positive patients compared to the general population and to assess the effect of prognostic factors. Material and Methods: We used generalized linear models with Poisson error structure to estimate overall and cause-specific excess of mortality in HIV-positive patients from 2004 to 2012 in the cohort of the Spanish Network of HIV Research (CoRIS, compared to Spanish general population and to assess the impact of multiple risk factors. We investigated differences between short-term and long-term risk factors effects on excess of mortality. Multiple Imputation by Chained Equations was used to deal with missing data. Results: In 9162 patients there were 363 deaths, 16.0% were non-AIDS malignancies, 10.5% liver and 0.3% cardiovascular related. Excess mortality was 1.20 deaths per 100 person years (py for all-cause mortality, 0.16 for liver, 0.10 for non-AIDS malignancies and 0.03 for cardiovascular. Short-term (first-year follow-up excess Hazard Ratio (eHR for global mortality for baseline AIDS was 4.27 (95% CI 3.06–6.01 and 1.47 (95% CI 0.95–2.27 for HCV coinfection; long-term (subsequent follow-up eHR for baseline AIDS was 0.88 (95% CI 0.58–1.35 and 4.48 (95% CI 2.71–7.42 for HCV coinfection. Lower CD4 count and higher viral load at entry, lower education, being male and over 50 years were predictors for overall excess mortality. Excess of liver mortality was higher in patients with CD4 counts at entry below 200 cells compared to those above 350 (eHR: 6.49, 95% CI 1.21–34.84 and in HCV-coinfected patients (eHR: 3.85, 95% CI 0.85– 17.37, although it was borderline significant. Patients over 50 years old (eHR: 5.55, 95%CI 2.4–12.85 and HCV coinfected (eHR: 5.81, 95% CI 2.6–13 showed a higher risk of non-AIDS malignancies mortality

  20. Automated pipeline for rapid production and screening of HIV-specific monoclonal antibodies using pichia pastoris.

    Science.gov (United States)

    Shah, Kartik A; Clark, John J; Goods, Brittany A; Politano, Timothy J; Mozdzierz, Nicholas J; Zimnisky, Ross M; Leeson, Rachel L; Love, J Christopher; Love, Kerry R

    2015-12-01

    Monoclonal antibodies (mAbs) that bind and neutralize human pathogens have great therapeutic potential. Advances in automated screening and liquid handling have resulted in the ability to discover antigen-specific antibodies either directly from human blood or from various combinatorial libraries (phage, bacteria, or yeast). There remain, however, bottlenecks in the cloning, expression and evaluation of such lead antibodies identified in primary screens that hinder high-throughput screening. As such, "hit-to-lead identification" remains both expensive and time-consuming. By combining the advantages of overlap extension PCR (OE-PCR) and a genetically stable yet easily manipulatable microbial expression host Pichia pastoris, we have developed an automated pipeline for the rapid production and screening of full-length antigen-specific mAbs. Here, we demonstrate the speed, feasibility and cost-effectiveness of our approach by generating several broadly neutralizing antibodies against human immunodeficiency virus (HIV).

  1. Drug-class specific impact of antivirals on the reproductive capacity of HIV.

    Directory of Open Access Journals (Sweden)

    Max von Kleist

    2010-03-01

    Full Text Available Predictive markers linking drug efficacy to clinical outcome are a key component in the drug discovery and development process. In HIV infection, two different measures, viral load decay and phenotypic assays, are used to assess drug efficacy in vivo and in vitro. For the newly introduced class of integrase inhibitors, a huge discrepancy between these two measures of efficacy was observed. Hence, a thorough understanding of the relation between these two measures of drug efficacy is imperative for guiding future drug discovery and development activities in HIV. In this article, we developed a novel viral dynamics model, which allows for a mechanistic integration of the mode of action of all approved drugs and drugs in late clinical trials. Subsequently, we established a link between in vivo and in vitro measures of drug efficacy, and extract important determinants of drug efficacy in vivo. The analysis is based on a new quantity-the reproductive capacity-that represents in mathematical terms the in vivo analog of the read-out of a phenotypic assay. Our results suggest a drug-class specific impact of antivirals on the total amount of viral replication. Moreover, we showed that the (drug-target half life, dominated by immune-system related clearance processes, is a key characteristic that affects both the emergence of resistance as well as the in vitro-in vivo correlation of efficacy measures in HIV treatment. We found that protease- and maturation inhibitors, due to their target half-life, decrease the total amount of viral replication and the emergence of resistance most efficiently.

  2. Differences in the expressed HLA class I alleles effect the differential clustering of HIV type 1-specific T cell responses in infected Chinese and Caucasians

    Institute of Scientific and Technical Information of China (English)

    Yu,XG; Addo,MM; Perkins,BA; Wej,FL; Rathod,A; Geer,SC; Parta,M; Cohen,D; Stone,DR; Russell,CJ; Tanzi,G; Mei,S; Wureel,AG; Frahm,N; Lichterfeld,M; Heath,L; Mullins,JI; Marincola,F; Goulder,PJR; Brander,C; Allen,T; Cao,YZ; Walker,BD; Altfeld,M

    2005-01-01

    China is a region of the world with a rapidly spreading HIV-1 epidemic. Studies providing insights into HIV-1 pathogenesis in infected Chinese are urgently needed to support the design and testing of an effective HIV-1 vaccine for this population. HIV-1-specific T cell responses were characterized in 32 HIV-1-infected individuals of Chinese origin and compared to 34 infected caucasians using 410 overlapping peptides spanning the entire HIV-1 clade B consensus sequence in an IFN-gamma ELISpot assay. All HIV-1 proteins were targeted with similar frequency in both populations and all study subjects recognized at least one overlapping peptide. HIV-1-specific T cell responses clustered in seven different regions of the HIV-1 genome in the Chinese cohort and in nine different regions in the caucasian cohort. The dominant HLA class I alleles expressed in the two populations differed significantly, and differences in epitope clustering pattern were shown to be influenced by differences in class I alleles that restrict immunodominant epitopes. These studies demonstrate that the clustering of HIV-1-specific T cell responses is influenced by the genetic HLA class I background in the study populations. The design and testing of candidate vaccines to fight the rapidly growing HIV-1 epidemic must therefore take the HLA genetics of the population into account as specific regions of the virus can be expected to be differentially targeted in ethnically diverse populations.

  3. Association of Neisseria gonorrhoeae Opa(CEA with dendritic cells suppresses their ability to elicit an HIV-1-specific T cell memory response.

    Directory of Open Access Journals (Sweden)

    Qigui Yu

    Full Text Available Infection with Neisseria gonorrhoeae (N. gonorrhoeae can trigger an intense local inflammatory response at the site of infection, yet there is little specific immune response or development of immune memory. Gonococcal surface epitopes are known to undergo antigenic variation; however, this is unlikely to explain the weak immune response to infection since individuals can be re-infected by the same serotype. Previous studies have demonstrated that the colony opacity-associated (Opa proteins on the N. gonorrhoeae surface can bind human carcinoembryonic antigen-related cellular adhesion molecule 1 (CEACAM1 on CD4⁺ T cells to suppress T cell activation and proliferation. Interesting in this regard, N. gonorrhoeae infection is associated with impaired HIV-1 (human immunodeficiency virus type 1-specific cytotoxic T-lymphocyte (CTL responses and with transient increases in plasma viremia in HIV-1-infected patients, suggesting that N. gonorrhoeae may also subvert immune responses to co-pathogens. Since dendritic cells (DCs are professional antigen presenting cells (APCs that play a key role in the induction of an adaptive immune response, we investigated the effects of N. gonorrhoeae Opa proteins on human DC activation and function. While morphological changes reminiscent of DC maturation were evident upon N. gonorrhoeae infection, we observed a marked downregulation of DC maturation marker CD83 when the gonococci expressing CEACAM1-specific Opa(CEA, but not other Opa variants. Consistent with a gonococcal-induced defect in maturation, Opa(CEA binding to CEACAM1 reduced the DCs' capacity to stimulate an allogeneic T cell proliferative response. Moreover, Opa(CEA-expressing N. gonorrhoeae showed the potential to impair DC-dependent development of specific adaptive immunity, since infection with Opa(CEA-positive gonococci suppressed the ability of DCs to stimulate HIV-1-specific memory CTL responses. These results reveal a novel mechanism to explain

  4. Characteristics of HIV-1-specific CD8 T-cell responses and their role in loss of viremia in children chronically infected with HIV-1 undergoing highly active antiretroviral therapy

    Institute of Scientific and Technical Information of China (English)

    ZHANG Zheng; ZHAO Qing-xia; FU Jun-liang; YAO Jin-xia; HE Yun; JIN Lei; WANG Fu-sheng

    2006-01-01

    Background Few studies have examined the properties of human immunodeficiency virus type 1 (HIV-1) epitope-specific cytotoxic T lymphocyte (CTL) responses in children. To address this issue, we characterized epitope-specific CTL responses and analyzed the determinants that may affect CTL responses before and after highly active antiretroviral therapy (HAART) in children with HIV-1 infection.Methods A total of 22 HIV-1-infected children and 23 uninfected healthy children as control were enrolled in the study. Circulating CD4 T cells and HIV-1 RNA load in plasma were routinely measured. Peripheral HIV-1-specific CTL frequency and HIV-1 epitope-specific, interferon-γ (IFN-γ)-producing T lymphocytes were measured using tetramer staining and enzyme-linked immunospot (ELISPOT) assay, respectively.Circulating dendritic cell (DC) subsets were monitored with FACS analysis.Results More than 80% of the children with HIV-1 infection exhibited a positive HIV-1-epitope-specific CTL response at baseline, but HIV-specific CTLs and IFN-γ-producing lymphocytes decreased in patients who responded to HAART in comparison with non-responders and HAART-naive children. The duration of virus suppression resulted from HAART was inversely correlated with CTL frequency. While in HAART-naive children, HIV-1-specific CTL frequency was positively correlated with myeloid DC (mDC) frequency,although the cause and effect relationship between the DCs and CTLs remains unknown.Conclusions HIV-1-epitope-specific CTL responses are dependent on antigenic stimulation. The impaired DC subsets in blood might result in a defect in DC-mediated T cell responses. These findings may provide insight into understanding the factors and related mechanisms that influence the outcome of HIV-1 carriers to HAART or future antiviral therapies.

  5. Specific cellular delivery and intracellular fate of quantum dot- peptide and quantum dot-polymer nanoassemblies

    Science.gov (United States)

    Delehanty, James B.; Bradburne, Christopher E.; Medintz, Igor L.; Farrell, Dorothy; Pons, Thomas; Brunel, Florence M.; Dawson, Philip E.; Mattoussi, Hedi

    2008-02-01

    Luminescent semiconductor quantum dots (QDs) possess several unique optical and spectroscopic properties that are of great interest and promise in biology. These properties suggest that QDs will be integral to the development of the next generation of biosensors capable of detecting molecular processes in both living and fixed cells. We are developing robust and facile delivery schemes for the selective intracellular delivery of QD-based nanoassemblies. These schemes are based upon the self-assembly and subsequent cellular uptake of QD-peptide and QD-polymer bioconjugates. The QD-peptide structures are generated by the self-assembly of the peptide onto CdSe-ZnS core-shell QDs via metal ion coordination between the peptide's polyhistidine motif and the Zn-rich QD shell. The polymer-based QD assemblies are formed via the electrostatic interaction of aqueous cationic liposomes with available carboxylate moieties on the QD surface ligands. Cellular delivery experiments utilizing both delivery schemes will be presented. The advantages and disadvantages of each approach will be discussed, including the intracellular fate and stability of the QD-nanoassemblies.

  6. Superimposed epitopes restricted by the same HLA molecule drive distinct HIV-specific CD8+ T cell repertoires.

    Science.gov (United States)

    Sun, Xiaoming; Fujiwara, Mamoru; Shi, Yi; Kuse, Nozomi; Gatanaga, Hiroyuki; Appay, Victor; Gao, George F; Oka, Shinichi; Takiguchi, Masafumi

    2014-07-01

    Superimposed epitopes, in which a shorter epitope is embedded within a longer one, can be presented by the same HLA class I molecule. CD8(+) CTL responses against such epitopes and the contribution of this phenomenon to immune control are poorly characterized. In this study, we examined HLA-A*24:02-restricted CTLs specific for the superimposed HIV Nef epitopes RYPLTFGWCF (RF10) and RYPLTFGW (RW8). Unexpectedly, RF10-specific and RW8-specific CTLs from HIV-1-infected HLA-A*24:02+ individuals had no overlapping Ag reactivity or clonotypic compositions. Single-cell TCR sequence analyses demonstrated that RF10-specific T cells had a more diverse TCR repertoire than did RW8-specific T cells. Furthermore, RF10-specific CTLs presented a higher Ag sensitivity and HIV suppressive capacity compared with RW8-specific CTLs. Crystallographic analyses revealed important structural differences between RF10- and RW8-HLA-A*24:02 complexes as well, with featured and featureless conformations, respectively, providing an explanation for the induction of distinct T cell responses against these epitopes. The present study shows that a single viral sequence containing superimposed epitopes restricted by the same HLA molecule could elicit distinct CD8+ T cell responses, therefore enhancing the control of HIV replication. This study also showed that a featured epitope (e.g., RF10) could drive the induction of T cells with high TCR diversity and affinity. Copyright © 2014 by The American Association of Immunologists, Inc.

  7. Application of magnetic field hyperthermia and superparamagnetic iron oxide nanoparticles to HIV-1-specific T-cell cytotoxicity

    Directory of Open Access Journals (Sweden)

    Williams JP

    2013-07-01

    Full Text Available James P Williams,1 Paul Southern,2 Anya Lissina,3 Helen C Christian,4 Andrew K Sewell,3 Rodney Phillips,1,5,6 Quentin Pankhurst,2 John Frater1,5,6 1Nuffield Department of Clinical Medicine, John Radcliffe Hospital, Oxford, UK; 2Davy-Faraday Research Laboratory, Royal Institution of Great Britain, London, UK; 3Institute of Infection and Immunity, Cardiff University School of Medicine, Cardiff, UK; 4Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, UK; 5James Martin 21st Century School, John Radcliffe Hospital, Oxford, UK; 6Oxford NIHR Biomedical Research Centre, Oxford, UK Abstract: The latent HIV-1 reservoir remains the major barrier to HIV-1 eradication. Although successful at limiting HIV replication, highly active antiretroviral therapy is unable to cure HIV infection, thus novel therapeutic strategies are needed to eliminate the virus. Magnetic field hyperthermia (MFH generates thermoablative cytotoxic temperatures in target-cell populations, and has delivered promising outcomes in animal models, as well as in several cancer clinical trials. MFH has been proposed as a strategy to improve the killing of HIV-infected cells and for targeting the HIV latent reservoirs. We wished to determine whether MFH could be used to enhance cytotoxic T-lymphocyte (CTL targeting of HIV-infected cells in a proof-of-concept study. Here, for the first time, we apply MFH to an infectious disease (HIV-1 using the superparamagnetic iron oxide nanoparticle FeraSpin R. We attempt to improve the cytotoxic potential of T-cell receptor-transfected HIV-specific CTLs using thermotherapy, and assess superparamagnetic iron oxide nanoparticle toxicity, uptake, and effect on cell function using more sensitive methods than previously described. FeraSpin R exhibited only limited toxicity, demonstrated efficient uptake and cell-surface attachment, and only modestly impacted T-cell function. In contrast to the cancer models, insufficient MFH was

  8. Confocal microscopy-based three-dimensional cell-specific modeling for large deformation analyses in cellular mechanics.

    Science.gov (United States)

    Slomka, Noa; Gefen, Amit

    2010-06-18

    This study introduces a new confocal microscopy-based three-dimensional cell-specific finite element (FE) modeling methodology for simulating cellular mechanics experiments involving large cell deformations. Three-dimensional FE models of undifferentiated skeletal muscle cells were developed by scanning C2C12 myoblasts using a confocal microscope, and then building FE model geometries from the z-stack images. Strain magnitudes and distributions in two cells were studied when the cells were subjected to compression and stretching, which are used in pressure ulcer and deep tissue injury research to induce large cell deformations. Localized plasma membrane and nuclear surface area (NSA) stretches were observed for both the cell compression and stretching simulation configurations. It was found that in order to induce large tensile strains (>5%) in the plasma membrane and NSA, one needs to apply more than approximately 15% of global cell deformation in cell compression tests, or more than approximately 3% of tensile strains in the elastic plate substrate in cell stretching experiments. Utilization of our modeling can substantially enrich experimental cellular mechanics studies in classic cell loading designs that typically involve large cell deformations, such as static and cyclic stretching, cell compression, micropipette aspiration, shear flow and hydrostatic pressure, by providing magnitudes and distributions of the localized cellular strains specific to each setup and cell type, which could then be associated with the applied stimuli.

  9. Neurotransmitter Specific, Cellular-Resolution Functional Brain Mapping Using Receptor Coated Nanoparticles: Assessment of the Possibility.

    Directory of Open Access Journals (Sweden)

    Ebrahim Forati

    Full Text Available Receptor coated resonant nanoparticles and quantum dots are proposed to provide a cellular-level resolution image of neural activities inside the brain. The functionalized nanoparticles and quantum dots in this approach will selectively bind to different neurotransmitters in the extra-synaptic regions of neurons. This allows us to detect neural activities in real time by monitoring the nanoparticles and quantum dots optically. Gold nanoparticles (GNPs with two different geometries (sphere and rod and quantum dots (QDs with different sizes were studied along with three different neurotransmitters: dopamine, gamma-Aminobutyric acid (GABA, and glycine. The absorption/emission spectra of GNPs and QDs before and after binding of neurotransmitters and their corresponding receptors are reported. The results using QDs and nanorods with diameter 25nm and aspect rations larger than three were promising for the development of the proposed functional brain mapping approach.

  10. Neurotransmitter Specific, Cellular-Resolution Functional Brain Mapping Using Receptor Coated Nanoparticles: Assessment of the Possibility

    Science.gov (United States)

    Forati, Ebrahim; Sabouni, Abas; Ray, Supriyo; Head, Brian; Schoen, Christian; Sievenpiper, Dan

    2015-01-01

    Receptor coated resonant nanoparticles and quantum dots are proposed to provide a cellular-level resolution image of neural activities inside the brain. The functionalized nanoparticles and quantum dots in this approach will selectively bind to different neurotransmitters in the extra-synaptic regions of neurons. This allows us to detect neural activities in real time by monitoring the nanoparticles and quantum dots optically. Gold nanoparticles (GNPs) with two different geometries (sphere and rod) and quantum dots (QDs) with different sizes were studied along with three different neurotransmitters: dopamine, gamma-Aminobutyric acid (GABA), and glycine. The absorption/emission spectra of GNPs and QDs before and after binding of neurotransmitters and their corresponding receptors are reported. The results using QDs and nanorods with diameter 25nm and aspect rations larger than three were promising for the development of the proposed functional brain mapping approach. PMID:26717196

  11. Modulation of polyfunctional HIV-specific CD8 T cells in patients responding differently to antiretroviral therapy.

    Science.gov (United States)

    Casetti, R; De Simone, G; Sacchi, A; Bordoni, V; Viola, D; Rinaldi, A; Agrati, C; Gioia, C; Martini, F

    2014-01-01

    Antiretroviral therapy allows a restoration of immune cell homeostasis associated with a normal immune competence. Our goal was to analyze the modulation of polyfunctional HIV-specific CD8+ T-cell responses during antiretroviral therapy. HIV-infected individuals were divided into four groups according to CD4+ cell count and viral load at the moment of recruitment. Whole blood was stimulated with a pool of CD8-specific HIV-antigens to assess cytokine/chemokine production and cytotoxicity activity by using flow cytometry. The groups show different modulation in HIV-specific CD8+ T-cell responses. In particular, immunological failure showed different distributions of polyfunctional HIVspecific CD8+ responses, mainly due to an increase of cells producing CD107alpha/IFNgamma/IL-2/MIP-1beta. Our results indicate that this particular 4+ functional subset is a possible correlate of immunological failure. Considering the complexity of interactions among HAART, immune system and HIV, work is in progress to find correlates of therapy efficacy.

  12. Quantitative MS-based enzymology of caspases reveals distinct protein substrate specificities, hierarchies, and cellular roles.

    Science.gov (United States)

    Julien, Olivier; Zhuang, Min; Wiita, Arun P; O'Donoghue, Anthony J; Knudsen, Giselle M; Craik, Charles S; Wells, James A

    2016-04-05

    Proteases constitute the largest enzyme family, yet their biological roles are obscured by our rudimentary understanding of their cellular substrates. There are 12 human caspases that play crucial roles in inflammation and cell differentiation and drive the terminal stages of cell death. Recent N-terminomics technologies have begun to enumerate the diverse substrates individual caspases can cleave in complex cell lysates. It is clear that many caspases have shared substrates; however, few data exist about the catalytic efficiencies (kcat/KM) of these substrates, which is critical to understanding their true substrate preferences. In this study, we use quantitative MS to determine the catalytic efficiencies for hundreds of natural protease substrates in cellular lysate for two understudied members: caspase-2 and caspase-6. Most substrates are new, and the cleavage rates vary up to 500-fold. We compare the cleavage rates for common substrates with those found for caspase-3, caspase-7, and caspase-8, involved in apoptosis. There is little correlation in catalytic efficiencies among the five caspases, suggesting each has a unique set of preferred substrates, and thus more specialized roles than previously understood. We synthesized peptide substrates on the basis of protein cleavage sites and found similar catalytic efficiencies between the protein and peptide substrates. These data suggest the rates of proteolysis are dominated more by local primary sequence, and less by the tertiary protein fold. Our studies highlight that global quantitative rate analysis for posttranslational modification enzymes in complex milieus for native substrates is critical to better define their functions and relative sequence of events.

  13. Human papillomavirus clade A9 specific cellular immunity during the natural course of disease

    NARCIS (Netherlands)

    Hende, Muriel van den

    2012-01-01

    The immune system plays an important role in the balance between viral clearance and viral persistence in HPV related (pre)malignant lesions. In this thesis, we analyzed HPV clade A9-specific T-cell responses in relation to virological and clinical outcome to gain further insight into HPV-specific

  14. Do the epidemiology, physiological mechanisms and characteristics of hepatocellular carcinoma in HIV-infected patients justify specific screening policies?

    Science.gov (United States)

    Gelu-Simeon, Moana; Sobesky, Rodolphe; Haïm-Boukobza, Stéphanie; Ostos, Marita; Teicher, Elina; Fontaine, Hélène; Salmon-Ceron, Dominique; Meyer, Laurence; Trinchet, Jean-Claude; Paule, Bernard; Samuel, Didier; Lewin, Maïté; Duclos-Vallée, Jean-Charles

    2014-06-19

    Reducing the incidence of hepatocellular carcinoma (HCC) in HIV-infected patients has become a serious problem when managing these patients. There are many explanations for this disease evolution, which notably include their longer survival under effective antiviral therapy and also the more rapid evolution of chronic liver disease. Despite recent advances in the management of hepatitis B (HBV) and hepatitis C (HCV) viral diseases, which will probably increase the number of patients achieving a virological response, HIV-infected patients with cirrhosis are still at risk of the onset of HCC. This evolution to HCC is also correlated to other comorbidities such as excessive alcohol consumption and nonalcoholic steatohepatitis (NASH). HCC thus remains a public health issue in this population. The poor prognosis and aggressiveness of HCC have been fully demonstrated, but the mechanisms underlying this aggressiveness are not yet well defined. As well as underlying mechanisms that contribute to accelerating hepatocarcinogenesis in HIV-infected patients, there are other reasons why HIV-infected patients should be considered a higher risk population. This review discusses the principal epidemiological determinants; the mechanisms of pathogenesis; and the treatment of HCC in HIV/HBV and HIV/HCV coinfected patients. It also discusses the probable need to develop a specific screening policy for HCC in this population in order to prevent the rapid development and to make them more amenable to a curative treatment.

  15. Architectural insight into inovirus-associated vectors (IAVs) and development of IAV-based vaccines inducing humoral and cellular responses: implications in HIV-1 vaccines.

    Science.gov (United States)

    Hassapis, Kyriakos A; Stylianou, Dora C; Kostrikis, Leondios G

    2014-12-01

    Inovirus-associated vectors (IAVs) are engineered, non-lytic, filamentous bacteriophages that are assembled primarily from thousands of copies of the major coat protein gp8 and just five copies of each of the four minor coat proteins gp3, gp6, gp7 and gp9. Inovirus display studies have shown that the architecture of inoviruses makes all coat proteins of the inoviral particle accessible to the outside. This particular feature of IAVs allows foreign antigenic peptides to be displayed on the outer surface of the virion fused to its coat proteins and for more than two decades has been exploited in many applications including antibody or peptide display libraries, drug design, and vaccine development against infectious and non-infectious diseases. As vaccine carriers, IAVs have been shown to elicit both a cellular and humoral response against various pathogens through the display of antibody epitopes on their coat proteins. Despite their high immunogenicity, the goal of developing an effective vaccine against HIV-1 has not yet materialized. One possible limitation of previous efforts was the use of broadly neutralizing antibodies, which exhibited autoreactivity properties. In the past five years, however, new, more potent broadly neutralizing antibodies that do not exhibit autoreactivity properties have been isolated from HIV-1 infected individuals, suggesting that vaccination strategies aimed at producing such broadly neutralizing antibodies may confer protection against infection. The utilization of these new, broadly neutralizing antibodies in combination with the architectural traits of IAVs have driven the current developments in the design of an inovirus-based vaccine against HIV-1. This article reviews the applications of IAVs in vaccine development, with particular emphasis on the design of inoviral-based vaccines against HIV-1.

  16. Architectural Insight into Inovirus-Associated Vectors (IAVs and Development of IAV-Based Vaccines Inducing Humoral and Cellular Responses: Implications in HIV-1 Vaccines

    Directory of Open Access Journals (Sweden)

    Kyriakos A. Hassapis

    2014-12-01

    Full Text Available Inovirus-associated vectors (IAVs are engineered, non-lytic, filamentous bacteriophages that are assembled primarily from thousands of copies of the major coat protein gp8 and just five copies of each of the four minor coat proteins gp3, gp6, gp7 and gp9. Inovirus display studies have shown that the architecture of inoviruses makes all coat proteins of the inoviral particle accessible to the outside. This particular feature of IAVs allows foreign antigenic peptides to be displayed on the outer surface of the virion fused to its coat proteins and for more than two decades has been exploited in many applications including antibody or peptide display libraries, drug design, and vaccine development against infectious and non-infectious diseases. As vaccine carriers, IAVs have been shown to elicit both a cellular and humoral response against various pathogens through the display of antibody epitopes on their coat proteins. Despite their high immunogenicity, the goal of developing an effective vaccine against HIV-1 has not yet materialized. One possible limitation of previous efforts was the use of broadly neutralizing antibodies, which exhibited autoreactivity properties. In the past five years, however, new, more potent broadly neutralizing antibodies that do not exhibit autoreactivity properties have been isolated from HIV-1 infected individuals, suggesting that vaccination strategies aimed at producing such broadly neutralizing antibodies may confer protection against infection. The utilization of these new, broadly neutralizing antibodies in combination with the architectural traits of IAVs have driven the current developments in the design of an inovirus-based vaccine against HIV-1. This article reviews the applications of IAVs in vaccine development, with particular emphasis on the design of inoviral-based vaccines against HIV-1.

  17. Evidence that levels of the dimeric cellular transcription factor CP2 play little role in the activation of the HIV-1 long terminal repeat in vivo or following superinfection with herpes simplex virus type 1.

    Science.gov (United States)

    Zhong, F; Swendeman, S L; Popik, W; Pitha, P M; Sheffery, M

    1994-08-19

    The dimeric transcription factor CP2 binds a sequence element found near the transcription start site of the human immunodeficiency virus (HIV-1) long terminal repeat. Several groups have suggested that cellular factors binding this element might play a role in modulating HIV-1 promoter activity in vivo. For example, induction of latent HIV-1 gene expression in response to superinfection by herpes simplex virus type 1 (HSV-1) or cytomegalovirus is thought to be mediated, in part, by factors binding the CP2 site. In this report we began to examine directly the relationship between CP2 and expression of the HIV-1 promoter. First, we tested what effect HSV-1 infection of T cells had on the cellular levels of CP2. The results showed that HSV-1 infection led to a significant reduction in the level of CP2 DNA binding activity and protein within 20 h. Next, we tested the effect of overexpressing either the wild-type factor or a dominant negative variant of CP2 on HIV-1 promoter activity in vivo. The results showed that CP2 had little effect or slightly repressed HIV-1 promoter activity in vivo. In addition, these expression constructs had little effect on the induction of HIV-1 promoter activity elicited by HSV-1 infection.

  18. Genetically encoded norbornene directs site-specific cellular protein labelling via a rapid bioorthogonal reaction

    OpenAIRE

    Lang, Kathrin; Davis, Lloyd; Torres-Kolbus, Jessica; Chou, Chungjung; Deiters, Alexander; Chin, Jason W.

    2012-01-01

    The site-specific incorporation of bioorthogonal groups via genetic code expansion provides a powerful general strategy for site-specifically labelling proteins with any probe. However, the slow reactivity of the bioorthogonal functional groups that can be encoded genetically limits the utility of this strategy. We demonstrate the genetic encoding of a norbornene amino acid using the pyrrolysyl tRNA synthetase/tRNACUA pair in Escherichia coli and mammalian cells. We developed a series of tetr...

  19. Oral vaccination with a recombinant Salmonella vaccine vector provokes systemic HIV-1 subtype C Gag-specific CD4+ Th1 and Th2 cell immune responses in mice

    Directory of Open Access Journals (Sweden)

    Williamson Anna-Lise

    2009-06-01

    Full Text Available Abstract Background Recombinant Salmonella vaccine vectors may potentially be used to induce specific CD4+ T cell responses against foreign viral antigens. Such immune responses are required features of vaccines against pathogens such as human immunodeficiency virus type 1 (HIV-1. The aim of this study was to investigate the induction of systemic HIV-1-specific CD4+ T helper (Th responses in mice after oral immunization with a live attenuated Salmonella vaccine vector that expressed HIV-1 subtype C Gag. Groups of BALB/c mice were vaccinated orally three times (4 weeks apart with this recombinant Salmonella. At sacrifice, 28 days after the last immunization, systemic CD4+ Th1 and Th2 cytokine responses were evaluated by enzyme-linked immunospot assay and cytometric bead array. HIV-1 Gag-specific IgG1 and IgG2a humoral responses in the serum were determined by enzyme-linked immunosorbent assay. Results Mice vaccinated with the recombinant Salmonella elicited both HIV-1-specific Th1 (interferon-gamma (IFN-γ and tumour necrosis factor-alpha (TNF-α and Th2 (interleukin-4 (IL-4 and interleukin-5 (IL-5 cytokine responses. The vaccine induced 70 (IFN-γ spot-forming units (SFUs/10e6 splenocytes and 238 IL-4 SFUs/10e6 splenocytes. Splenocytes from vaccinated mice also produced high levels of Th1 and Th2 cytokines upon stimulation with a Gag CD4 peptide. The levels of IFN-γ, TNF-α, IL-4 and IL-5 were 7.5-, 29.1-, 26.2- and 89.3-fold above the background, respectively. Both HIV-1 Gag-specific IgG1 and IgG2a antibodies were detected in the sera of vaccinated mice. Conclusion The study highlights the potential of orally-delivered attenuated Salmonella as mucosal vaccine vectors for HIV-1 Subtype C Gag to induce Gag-specific CD4+ Th1 and Th2 cellular immune responses and antibodies which may be important characteristics required for protection against HIV-1 infection.

  20. Immunological changes in human immunodeficiency virus (HIV)-infected individuals during HIV-specific protease inhibitor treatment

    DEFF Research Database (Denmark)

    Ullum, H; Katzenstein, T; Aladdin, H

    1999-01-01

    The present study examines the influence of effective anti-retroviral treatment on immune function, evaluated by a broad array of immunological tests. We followed 12 individuals infected with human immunodeficiency virus (HIV) for 6 months after initiation of combination anti-retroviral treatment...

  1. Protein synthesis patterns of Paracoccidiodes brasiliensis isolates in stage-specific forms and during cellular differentiation.

    Science.gov (United States)

    Salem-Izacc, S M; Jesuino, R S; Brito, W A; Pereira, M; Felipe, M S; Soares, C M

    1997-01-01

    In this paper we compared the protein synthesis patterns of Paracoccidioides brasiliensis isolates. The protein profiles were compared for both yeast and mycelial forms and similarity analysis among them was performed by calculating similarity matrices and grouping the isolates in dendrograms. The examined isolates exhibited highly variable cellular morphology at 36 degrees C, when typical yeast cells were expected. On the other hand, at 26 degrees C all the isolates showed mycelial morphology. The analysis of protein synthesis profiles made it possible to cluster the P. brasiliensis isolates into groups that correlated with the morphological data. Interestingly, growth at 36 degrees C strongly decreased the heterogeneity of protein synthesis patterns seen in mycelial isolates. It was possible to cluster the isolates grown at 36 degrees C in three groups based on their two-dimensional protein synthesis analysis. The similarity index observed among the mycelial isolates was lower than that obtained with yeast cells, suggesting a more homogenous gene expression pattern in the host-adapted form than in the saprobic phase.

  2. Reactive oxygen species involved cancer cellular specific 5-aminolevulinic acid uptake in gastric epithelial cells.

    Science.gov (United States)

    Ito, Hiromu; Tamura, Masato; Matsui, Hirofumi; Majima, Hideyuki J; Indo, Hiroko P; Hyodo, Ichinosuke

    2014-03-01

    Photodynamic therapy and photodynamic diagnosis using 5-aminolevulinic acid (ALA) are clinically useful for cancer treatments. Cancer cells have been reported that 5-aminolevulinic acid is incorporated via peptide transporter 1, which is one of the membrane transport proteins, and has been reported to be significantly expressed in various gastrointestinal cancer cells such as Caco-2. However, the mechanism of this protein expression has not been elucidated. Concentration of reactive oxygen species (ROS) is higher in cancer cells in comparison with that of normal cells. We have previously reported that ROS derived from mitochondria is likely related to invasions and proliferations of cancer cells. Since 5-aminolevulinic acid is the most important precursor of heme which is necessary protein for cellular proliferations, mitochondrial ROS (mitROS) may be also related to peptide transporter 1 expressions. In this study, we used a rat gastric mucosal cell line RGM1 and its cancer-like mutated cell line RGK1, and we clarified the ALA uptake mechanism and its relations between mitROS and peptide transporter 1 expression in RGK1. We also used our self-established stable clone of cell which over-expresses manganese superoxide dismutase, a mitROS scavenger. We studied differences of the photodynamic therapy effects in these cells after ALA administrations to clear the influence of mitROS.

  3. Analysis of cellular phenotype during in vitro immunization of murine splenocytes for generating antigen-specific immunoglobulin.

    Science.gov (United States)

    Inagaki, Takashi; Yoshimi, Tatsunari; Kobayashi, Satoshi; Kawahara, Masahiro; Nagamune, Teruyuki

    2013-03-01

    Although various in vitro immunization methods to generate antigen-specific antibodies have been described, a highly effective method that can generate high-affinity immunoglobulins has not yet been reported. Herein, we analyzed a cellular phenotype during in vitro immunization of murine splenocytes for generating antigen-specific immunoglobulins. We identified a combination of T cell-dependent stimuli (IL-4, IL-5, anti-CD38 and anti-CD40 antibodies) plus lipopolysaccharides (LPS) that stimulates antigen-exposed splenocytes in vitro, followed by induction of the cells phenotypically equivalent to germinal center B cells. We also observed that LPS induced high expression levels of mRNA for activation-induced cytidine deaminase. We stimulated antigen-exposed splenocytes, followed by the accumulation of mutations in immunoglobulin genes. From the immunized splenocytes, hybridoma clones secreting antigen-specific immunoglobulins were obtained.

  4. Cellular Levels of HIV Unspliced RNA from Patients on Combination Antiretroviral Therapy with Undetectable Plasma Viremia Predict the Therapy Outcome

    NARCIS (Netherlands)

    Pasternak, A.O.; Jurriaans, S.; Bakker, M.; Prins, J.M.; Berkhout, B.; Lukashov, V.V.

    2009-01-01

    Background: Combination antiretroviral therapy (cART), the standard of care for HIV-1 infection, is considered to be successful when plasma viremia remains below the detection limit of commercial assays. Yet, cART fails in a substantial proportion of patients after the apparent success. No laborator

  5. Immunosuppressive activity of Semen Persicae ethanol extract on specific antibody and cellular response to ovalbumin in mice.

    Science.gov (United States)

    Zhang, Yi-Bin; Qin, Feng; Sun, Hong-Xiang

    2006-09-01

    The immunosuppressive activity of the ethanol extract of Semen Persicae (EESP) was studied with respect to specific antibody and cellular response to ovalbumin (OVA) in mice. The effects of EESP on mice splenocyte proliferation in vitro were measured. EESP significantly suppressed concanavalin A (ConA)- and lipopolysaccharide (LPS)-stimulated splenocyte proliferation in vitro in a concentration-dependent manner. Furthermore, the effects of EESP at three dose levels on the humoral and cellular immune responses in the OVA-immunized mice were examined. ICR Mice were immunized subcutaneously with OVA on day 0 and 14. Starting on the day of immunization, the mice were administered intraperitoneally with EESP at a single dose of 0.25, 0.5, and 1.0 mg, and cyclosporin A (CsA, positive drug) at a single dose of 0.1 mg at intervals of 7 days. On day 28, mitogen- and OVA-induced splenocyte proliferation and OVA-specific antibody level in serum were measured. EESP significantly decreased ConA-, LPS-, and OVA-induced splenocyte proliferation in the OVA-immunized mice at the dose of 1.0 mg. Meanwhile, the OVA-specific serum IgG, IgG1, and IgG2b antibody levels in the OVA-immunized mice were markedly reduced by EESP in a dose-dependent manner. The results suggest that EESP could suppress the cellular and humoral immune response in mice, and deserve further research to be developed as immunosuppressant.

  6. Prime-Boost Vaccination Using Chemokine-Fused gp120 DNA and HIV Envelope Peptides Activates Both Immediate and Long-Term Memory Cellular Responses in Rhesus Macaques

    Directory of Open Access Journals (Sweden)

    Hong Qin

    2010-01-01

    Full Text Available HIV vaccine candidates with improved immunogenicity and induction of mucosal T-cell immunity are needed. A prime-boost strategy using a novel HIV glycoprotein 120 DNA vaccine was employed to immunize rhesus macaques. The DNA vaccine encoded a chimeric gp120 protein in fusion with monocyte chemoattractant protein-3, which was hypothesized to improve the ability of antigen-presenting cells to capture viral antigen through chemokine receptor-mediated endocytosis. DNA vaccination induced virus-reactive T cells in peripheral blood, detectable by T cell proliferation, INFγ ELISPOT and sustained IL-6 production, without humoral responses. With a peptide-cocktail vaccine containing a set of conserved polypeptides of HIV-1 envelope protein, given by nasogastric administration, primed T-cell immunity was significantly boosted. Surprisingly, long-term and peptide-specific mucosal memory T-cell immunity was detected in both vaccinated macaques after one year. Therefore, data from this investigation offer proof-of-principle for potential effectiveness of the prime-boost strategy with a chemokine-fused gp120 DNA and warrant further testing in the nonhuman primate models for developing as a potential HIV vaccine candidate in humans.

  7. Curcumin-loaded apotransferrin nanoparticles provide efficient cellular uptake and effectively inhibit HIV-1 replication in vitro.

    Directory of Open Access Journals (Sweden)

    Upendhar Gandapu

    Full Text Available BACKGROUND: Curcumin (diferuloylmethane shows significant activity across a wide spectrum of conditions, but its usefulness is rather limited because of its low bioavailability. Use of nanoparticle formulations to enhance curcumin bioavailability is an emerging area of research. METHODOLOGY/PRINCIPAL FINDINGS: In the present study, curcumin-loaded apotransferrin nanoparticles (nano-curcumin prepared by sol-oil chemistry and were characterized by electron and atomic force microscopy. Confocal studies and fluorimetric analysis revealed that these particles enter T cells through transferrin-mediated endocytosis. Nano-curcumin releases significant quantities of drug gradually over a fairly long period, ∼50% of curcumin still remaining at 6 h of time. In contrast, intracellular soluble curcumin (sol-curcumin reaches a maximum at 2 h followed by its complete elimination by 4 h. While sol-curcumin (GI(50 = 15.6 µM is twice more toxic than nano-curcumin (GI(50 = 32.5 µM, nano-curcumin (IC(50<1.75 µM shows a higher anti-HIV activity compared to sol-curcumin (IC(50 = 5.1 µM. Studies in vitro showed that nano-curcumin prominently inhibited the HIV-1 induced expression of Topo II α, IL-1β and COX-2, an effect not seen with sol-curcumin. Nano-curcumin did not affect the expression of Topoisomerase II β and TNF α. This point out that nano-curcumin affects the HIV-1 induced inflammatory responses through pathways downstream or independent of TNF α. Furthermore, nano-curcumin completely blocks the synthesis of viral cDNA in the gag region suggesting that the nano-curcumin mediated inhibition of HIV-1 replication is targeted to viral cDNA synthesis. CONCLUSION: Curcumin-loaded apotransferrin nanoparticles are highly efficacious inhibitors of HIV-1 replication in vitro and promise a high potential for clinical usefulness.

  8. Specific behavioral and cellular adaptations induced by chronic morphine are reduced by dietary omega-3 polyunsaturated fatty acids.

    Science.gov (United States)

    Hakimian, Joshua; Minasyan, Ani; Zhe-Ying, Lily; Loureiro, Mariana; Beltrand, Austin; Johnston, Camille; Vorperian, Alexander; Romaneschi, Nicole; Atallah, Waleed; Gomez-Pinilla, Fernando; Walwyn, Wendy

    2017-01-01

    Opiates, one of the oldest known drugs, are the benchmark for treating pain. Regular opioid exposure also induces euphoria making these compounds addictive and often misused, as shown by the current epidemic of opioid abuse and overdose mortalities. In addition to the effect of opioids on their cognate receptors and signaling cascades, these compounds also induce multiple adaptations at cellular and behavioral levels. As omega-3 polyunsaturated fatty acids (n-3 PUFAs) play a ubiquitous role in behavioral and cellular processes, we proposed that supplemental n-3 PUFAs, enriched in docosahexanoic acid (DHA), could offset these adaptations following chronic opioid exposure. We used an 8 week regimen of n-3 PUFA supplementation followed by 8 days of morphine in the presence of this diet. We first assessed the effect of morphine in different behavioral measures and found that morphine increased anxiety and reduced wheel-running behavior. These effects were reduced by dietary n-3 PUFAs without affecting morphine-induced analgesia or hyperlocomotion, known effects of this opiate acting at mu opioid receptors. At the cellular level we found that morphine reduced striatal DHA content and that this was reversed by supplemental n-3 PUFAs. Chronic morphine also increased glutamatergic plasticity and the proportion of Grin2B-NMDARs in striatal projection neurons. This effect was similarly reversed by supplemental n-3 PUFAs. Gene analysis showed that supplemental PUFAs offset the effect of morphine on genes found in neurons of the dopamine receptor 2 (D2)-enriched indirect pathway but not of genes found in dopamine receptor 1(D1)-enriched direct-pathway neurons. Analysis of the D2 striatal connectome by a retrogradely transported pseudorabies virus showed that n-3 PUFA supplementation reversed the effect of chronic morphine on the innervation of D2 neurons by the dorsomedial prefontal and piriform cortices. Together these changes outline specific behavioral and cellular effects

  9. Assessment of Membrane Fluidity Fluctuations during Cellular Development Reveals Time and Cell Type Specificity

    KAUST Repository

    Noutsi, Pakiza

    2016-06-30

    Cell membrane is made up of a complex structure of lipids and proteins that diffuse laterally giving rise to what we call membrane fluidity. During cellular development, such as differentiation cell membranes undergo dramatic fluidity changes induced by proteins such as ARC and Cofilin among others. In this study we used the generalized polarization (GP) property of fluorescent probe Laurdan using two-photon microscopy to determine membrane fluidity as a function of time and for various cell lines. A low GP value corresponds to a higher fluidity and a higher GP value is associated with a more rigid membrane. Four different cell lines were monitored such as hN2, NIH3T3, HEK293 and L6 cells. Membrane fluidity was measured at 12h, 72h and 92 h. Our results show significant changes in membrane fluidity among all cell types at different time points. GP values tend to increase significantly within 92 h in hN2 cells and 72 h in NIH3T3 cells and only at 92 h in HEK293 cells. L6 showed a marked decrease in membrane fluidity at 72 h and starts to increase at 92 h. As expected, NIH3T3 cells have more rigid membrane at earlier time points. On the other hand, neurons tend to have the highest membrane fluidity at early time points emphasizing its correlation with plasticity and the need for this malleability during differentiation. This study sheds light on the involvement of membrane fluidity during neuronal differentiation and development of other cell lines.

  10. Assessment of Membrane Fluidity Fluctuations during Cellular Development Reveals Time and Cell Type Specificity.

    Directory of Open Access Journals (Sweden)

    Pakiza Noutsi

    Full Text Available Cell membrane is made up of a complex structure of lipids and proteins that diffuse laterally giving rise to what we call membrane fluidity. During cellular development, such as differentiation cell membranes undergo dramatic fluidity changes induced by proteins such as ARC and Cofilin among others. In this study we used the generalized polarization (GP property of fluorescent probe Laurdan using two-photon microscopy to determine membrane fluidity as a function of time and for various cell lines. A low GP value corresponds to a higher fluidity and a higher GP value is associated with a more rigid membrane. Four different cell lines were monitored such as hN2, NIH3T3, HEK293 and L6 cells. Membrane fluidity was measured at 12h, 72h and 92 h. Our results show significant changes in membrane fluidity among all cell types at different time points. GP values tend to increase significantly within 92 h in hN2 cells and 72 h in NIH3T3 cells and only at 92 h in HEK293 cells. L6 showed a marked decrease in membrane fluidity at 72 h and starts to increase at 92 h. As expected, NIH3T3 cells have more rigid membrane at earlier time points. On the other hand, neurons tend to have the highest membrane fluidity at early time points emphasizing its correlation with plasticity and the need for this malleability during differentiation. This study sheds light on the involvement of membrane fluidity during neuronal differentiation and development of other cell lines.

  11. Comprehensive longitudinal analysis of hepatitis C virus (HCV)-specific T cell responses during acute HCV infection in the presence of existing HIV-1 infection

    NARCIS (Netherlands)

    C.H.S.B. van den Berg; T.A. Ruys; N.M. Nanlohy; S.E. Geerlings; J.T. van der Meer; J.W. Mulder; J.A. Lange; D. van Baarle

    2009-01-01

    The aim of this study was to study the development of HCV-specific T cell immunity during acute HCV infection in the presence of an existing HIV-1 infection in four HIV-1 infected men having sex with men. A comprehensive analysis of HCV-specific T cell responses was performed at two time points duri

  12. Targeting Tuberculosis and HIV Infection-Specific Regulatory T Cells with MEK/ERK Signaling Pathway Inhibitors

    Science.gov (United States)

    Lieske, Nora V.; Tonby, Kristian; Kvale, Dag; Dyrhol-Riise, Anne M.; Tasken, Kjetil

    2015-01-01

    Human regulatory T cells (Tregs) are essential in maintaining immunological tolerance and suppress effector T cells. Tregs are commonly up-regulated in chronic infectious diseases such as tuberculosis (TB) and human immunodeficiency virus (HIV) infection and thereby hamper disease-specific immune responses and eradication of pathogens. The MEK/ERK signaling pathway is involved in regulation of the FoxP3 transcription factor, which directs a lineage-specific transcriptional program to define Tregs and control their suppressive function. Here, we aimed to target activation of disease-specific Tregs by inhibition of the MEK/ERK signaling pathway based on the hypothesis that this would improve anti-HIV and anti-TB immunity. Stimulation of T cells from untreated TB (n = 12) and HIV (n = 8) patients with disease-specific antigens in vitro in the presence of the MEK inhibitor (MEKI) trametinib (GSK1120212) resulted in significant down-regulation of both FoxP3 levels (MFI) and fractions of resting (CD45RA+FoxP3+) and activated (CD45RA−FoxP3++) Tregs. MEKI also reduced the levels of specific T effector cells expressing the pro-inflammatory cytokines (IFN-γ, TNF-α and IL-2) in both HIV and TB patients. In conclusion, MEKIs modulate disease antigen-specific Treg activation and may have potential application in new treatment strategies in chronic infectious diseases where reduction of Treg activity would be favorable. Whether MEKIs can be used in current HIV or TB therapy regimens needs to be further investigated. PMID:26544592

  13. Targeting Tuberculosis and HIV Infection-Specific Regulatory T Cells with MEK/ERK Signaling Pathway Inhibitors.

    Directory of Open Access Journals (Sweden)

    Nora V Lieske

    Full Text Available Human regulatory T cells (Tregs are essential in maintaining immunological tolerance and suppress effector T cells. Tregs are commonly up-regulated in chronic infectious diseases such as tuberculosis (TB and human immunodeficiency virus (HIV infection and thereby hamper disease-specific immune responses and eradication of pathogens. The MEK/ERK signaling pathway is involved in regulation of the FoxP3 transcription factor, which directs a lineage-specific transcriptional program to define Tregs and control their suppressive function. Here, we aimed to target activation of disease-specific Tregs by inhibition of the MEK/ERK signaling pathway based on the hypothesis that this would improve anti-HIV and anti-TB immunity. Stimulation of T cells from untreated TB (n = 12 and HIV (n = 8 patients with disease-specific antigens in vitro in the presence of the MEK inhibitor (MEKI trametinib (GSK1120212 resulted in significant down-regulation of both FoxP3 levels (MFI and fractions of resting (CD45RA+FoxP3+ and activated (CD45RA-FoxP3++ Tregs. MEKI also reduced the levels of specific T effector cells expressing the pro-inflammatory cytokines (IFN-γ, TNF-α and IL-2 in both HIV and TB patients. In conclusion, MEKIs modulate disease antigen-specific Treg activation and may have potential application in new treatment strategies in chronic infectious diseases where reduction of Treg activity would be favorable. Whether MEKIs can be used in current HIV or TB therapy regimens needs to be further investigated.

  14. Identification of amino acids in HIV-2 integrase involved in site-specific hydrolysis and alcoholysis of viral DNA termini

    NARCIS (Netherlands)

    D.C. van Gent (Dik); A.A. Groeneger; R.H. Plassterk

    1993-01-01

    textabstractThe human immunodeficiency virus integrase (HIV IN) protein cleaves two nucleotides off the 3' end of viral DNA and subsequently integrates the viral DNA into target DNA. IN exposes a specific phosphodiester bond near the viral DNA end to nucleophilic attack by water or

  15. Identification of amino acids in HIV-2 integrase involved in site-specific hydrolysis and alcoholysis of viral DNA termini

    NARCIS (Netherlands)

    D.C. van Gent (Dik); A.A. Groeneger; R.H. Plassterk

    1993-01-01

    textabstractThe human immunodeficiency virus integrase (HIV IN) protein cleaves two nucleotides off the 3' end of viral DNA and subsequently integrates the viral DNA into target DNA. IN exposes a specific phosphodiester bond near the viral DNA end to nucleophilic attack by water or

  16. Predefined GPGRAFY-Epitope-Specific Monoclonal Antibodies with Different Activities for Recognizing Native HIV-1 gp120

    Institute of Scientific and Technical Information of China (English)

    蓝灿辉; 田海军; 陈应华

    2004-01-01

    A seven-amino acid epitope GPGRAFY at the tip of the V3 loop in HIV-1 gp120 is the principal neutralizing epitope,and a subset of anti-V3 antibodies specific for this epitope shows a broad range of neutralizing activity.GPGRAFY-epitope-specific neutralizing antibodies were produced using predefined GPGRAFY-epitope-specific peptides instead of a natural or recombinant gp120 bearing this epitope.All six monoclonal antibodies (mAbs) could recognize the GPGRAFY-epitope on peptides and two of the antibodies,9D8 and 2D7,could recognize recombinant gp120 in enzymelinked immunosorkentassy (ELISA) assays.In the flow cytometry analysis,the mAbs 9D8 and 2D7 could bind to HIV-Env+ CHO-WT cells and the specific bindings could be inhibited by the GPGRAFY-epitope peptide,which suggests that these two mAbs could recognize the native envelope protein gp120 expressed on the cell membrane.However,in syncytium assays,none of the mAbs was capable of inhibiting HIV-Env-mediated cell membrane fusion.The different activities for recognizing native HIV-1 gp120 might be associated with different antibody affinities against the epitopes.The development of conformational mimics of the neutralization epitope in the gp120 V3 loop could elicit neutralizing mAbs with high affinity.

  17. Specific cellular stimulation in the primary immune response: experimental test of a quantized model.

    OpenAIRE

    Dintzis, R Z; Vogelstein, B; Dintzis, H M

    1982-01-01

    Dose-response and dose-suppression curves have been measured for the primary immune response in mice, in vivo and in vitro, by using size-fractionated linear polymers of acrylamide substituted with hapten. The results are in general agreement with a simple theory based on the premise that the specific primary immunological response is quantized at some fundamental and limiting step, requiring a minimum number of linked antigen receptors for response.

  18. A novel, live-attenuated vesicular stomatitis virus vector displaying conformationally intact, functional HIV-1 envelope trimers that elicits potent cellular and humoral responses in mice.

    Directory of Open Access Journals (Sweden)

    Svetlana Rabinovich

    Full Text Available Though vaccination with live-attenuated SIV provides the greatest protection from progressive disease caused by SIV challenge in rhesus macaques, attenuated HIV presents safety concerns as a vaccine; therefore, live viral vectors carrying HIV immunogens must be considered. We have designed a replication-competent vesicular stomatitis virus (VSV displaying immunogenic HIV-1 Env trimers and attenuating quantities of the native surface glycoprotein (G. The clade B Env immunogen is an Env-VSV G hybrid (EnvG in which the transmembrane and cytoplasmic tail regions are derived from G. Relocation of the G gene to the 5'terminus of the genome and insertion of EnvG into the natural G position induced a ∼1 log reduction in surface G, significant growth attenuation compared to wild-type, and incorporation of abundant EnvG. Western blot analysis indicated that ∼75% of incorporated EnvG was a mature proteolytically processed form. Flow cytometry showed that surface EnvG bound various conformationally- and trimer-specific antibodies (Abs, and in-vitro growth assays on CD4+CCR5+ cells demonstrated EnvG functionality. Neither intranasal (IN or intramuscular (IM administration in mice induced any observable pathology and all regimens tested generated potent Env-specific ELISA titers of 10(4-10(5, with an IM VSV prime/IN VSV boost regimen eliciting the highest binding and neutralizing Ab titers. Significant quantities of Env-specific CD4+ T cells were also detected, which were augmented as much as 70-fold by priming with IM electroporated plasmids encoding EnvG and IL-12. These data suggest that our novel vector can achieve balanced safety and immunogenicity and should be considered as an HIV vaccine platform.

  19. Two double-blinded, randomized, comparative trials of 4 human immunodeficiency virus type 1 (HIV-1) envelope vaccines in HIV-1-infected individuals across a spectrum of disease severity: AIDS Clinical Trials Groups 209 and 214.

    Science.gov (United States)

    Schooley, R T; Spino, C; Kuritzkes, D; Walker, B D; Valentine, F A; Hirsch, M S; Cooney, E; Friedland, G; Kundu, S; Merigan, T C; McElrath, M J; Collier, A; Plaeger, S; Mitsuyasu, R; Kahn, J; Haslett, P; Uherova, P; deGruttola, V; Chiu, S; Zhang, B; Jones, G; Bell, D; Ketter, N; Twadell, T; Chernoff, D; Rosandich, M

    2000-11-01

    The potential role of human immunodeficiency virus type 1 (HIV-1)-specific immune responses in controlling viral replication in vivo has stimulated interest in enhancing virus-specific immunity by vaccinating infected individuals with HIV-1 or its components. These studies were undertaken to define patient populations most likely to respond to vaccination, with the induction of novel HIV-1-specific cellular immune responses, and to compare the safety and immunogenicity of several candidate recombinant HIV-1 envelope vaccines and adjuvants. New lymphoproliferative responses (LPRs) developed in 350 cells/mm(3) and were usually strain restricted. Responders tended to be more likely than nonresponders to have an undetectable level of HIV-1 RNA at baseline (P=.067). Induction of new cellular immune responses by HIV-1 envelope vaccines is a function of the immunologic stage of disease and baseline plasma HIV-1 RNA level and exhibits considerable vaccine strain specificity.

  20. Antiviral Innate Immune Activation in HIV-Infected Adults Negatively Affects H1/IC31-Induced Vaccine-Specific Memory CD4+ T Cells.

    Science.gov (United States)

    Lenz, Nicole; Schindler, Tobias; Kagina, Benjamin M; Zhang, Jitao David; Lukindo, Tedson; Mpina, Maxmillian; Bang, Peter; Kromann, Ingrid; Hoff, Søren T; Andersen, Peter; Reither, Klaus; Churchyard, Gavin J; Certa, Ulrich; Daubenberger, Claudia A

    2015-07-01

    Tuberculosis (TB) remains a global health problem, with vaccination being a necessary strategy for disease containment and elimination. A TB vaccine should be safe and immunogenic as well as efficacious in all affected populations, including HIV-infected individuals. We investigated the induction and maintenance of vaccine-induced memory CD4(+) T cells following vaccination with the subunit vaccine H1/IC31. H1/IC31 was inoculated twice on study days 0 and 56 among HIV-infected adults with CD4(+) lymphocyte counts of >350 cells/mm(3). Whole venous blood stimulation was conducted with the H1 protein, and memory CD4(+) T cells were analyzed using intracellular cytokine staining and polychromatic flow cytometry. We identified high responders, intermediate responders, and nonresponders based on detection of interleukin-2 (IL-2), tumor necrosis factor alpha (TNF-α), and gamma interferon (IFN-γ) expressing central (TCM) and effector memory CD4(+) T cells (TEM) 182 days after the first immunization. Amplicon-based transcript quantification using next-generation sequencing was performed to identify differentially expressed genes that correlated with vaccine-induced immune responses. Genes implicated in resolution of inflammation discriminated the responders from the nonresponders 3 days after the first inoculation. The volunteers with higher expression levels of genes involved in antiviral innate immunity at baseline showed impaired H1-specific TCM and TEM maintenance 6 months after vaccination. Our study showed that in HIV-infected volunteers, expression levels of genes involved in the antiviral innate immune response affected long-term maintenance of H1/IC31 vaccine-induced cellular immunity. (The clinical trial was registered in the Pan African Clinical Trials Registry [PACTR] with the identifier PACTR201105000289276.). Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  1. The specifically enhanced cellular immune responses in Pacific oyster (Crassostrea gigas) against secondary challenge with Vibrio splendidus.

    Science.gov (United States)

    Zhang, Tao; Qiu, Limei; Sun, Zhibin; Wang, Lingling; Zhou, Zhi; Liu, Rui; Yue, Feng; Sun, Rui; Song, Linsheng

    2014-07-01

    The increasing experimental evidences suggest that there are some forms of specific acquired immunity in invertebrates, but the underlying mechanism is not fully understood. In the present study, Pacific oyster (Crassostrea gigas) stimulated primarily by heat-killed Vibrio splendidus displayed stronger immune responses at cellular and molecular levels when they encountered the secondary challenge of live V. splendidus. The total hemocyte counts (THC) increased significantly after the primary stimulation of heat-killed V. splendidus, and it increased even higher (p oysters received the secondary stimulation with live V. splendidus, and the phagocytic rate was also enhanced significantly (p oysters after the secondary stimulation of V. splendidus were higher (p oyster with specifically enhanced phagocytosis and rapidly promoted regeneration of circulating hemocytes when the primed oysters encountered the secondary challenge with V. splendidus.

  2. Cause-Specific Mortality in HIV-Positive Patients Who Survived Ten Years after Starting Antiretroviral Therapy

    DEFF Research Database (Denmark)

    Trickey, Adam; May, Margaret T; Vehreschild, Jorg-Janne

    2016-01-01

    years 656/13,011 (5%) patients died. Older age, male sex, injecting drug use transmission, AIDS, and low CD4 count and detectable viral replication ten years after starting combination antiretroviral therapy were associated with higher subsequent mortality. CD4 count at ART start did not predict......OBJECTIVES: To estimate mortality rates and prognostic factors in HIV-positive patients who started combination antiretroviral therapy between 1996-1999 and survived for more than ten years. METHODS: We used data from 18 European and North American HIV cohort studies contributing...... to the Antiretroviral Therapy Cohort Collaboration. We followed up patients from ten years after start of combination antiretroviral therapy. We estimated overall and cause-specific mortality rate ratios for age, sex, transmission through injection drug use, AIDS, CD4 count and HIV-1 RNA. RESULTS: During 50,593 person...

  3. Interdisciplinary Analysis of HIV-Specific CD8(+) T Cell Responses against Variant Epitopes Reveals Restricted TCR Promiscuity

    DEFF Research Database (Denmark)

    Hoof, Ilka; Perez, C.L.; Buggert, M.

    2010-01-01

    HIV-1 specific CTL responses play a key role in limiting viral replication. CTL responses are sensitive to viral escape mutations, which influence recognition of the virus. Although CTLs have been shown to recognize epitope variants, the extent of this cross-reactivity has not been quantitatively...... are useful to study the complex pattern of CTL responses exhibited by an HIV-1 infected patient cohort and for identification of optimal targets for novel therapeutic or vaccine approaches. The Journal of Immunology, 2010, 184: 5383-5391.......HIV-1 specific CTL responses play a key role in limiting viral replication. CTL responses are sensitive to viral escape mutations, which influence recognition of the virus. Although CTLs have been shown to recognize epitope variants, the extent of this cross-reactivity has not been quantitatively...... investigated in a genetically diverse cohort of HIV-1 infected patients. Using a novel bioinformatic binding prediction method, we aimed to explain the pattern of epitope-specific CTL responses based on the patients' HLA genotype and autologous virus sequence quantitatively. Sequences covering predicted...

  4. Depression and HIV in Botswana: a population-based study on gender-specific socioeconomic and behavioral correlates.

    Directory of Open Access Journals (Sweden)

    Reshma Gupta

    Full Text Available BACKGROUND: Depression is a leading contributor to the burden of disease worldwide, a critical barrier to HIV prevention and a common serious HIV co-morbidity. However, depression screening and treatment are limited in sub-Saharan Africa, and there are few population-level studies examining the prevalence and gender-specific factors associated with depression. METHODS: We conducted a cross-sectional population-based study of 18-49 year-old adults from five districts in Botswana with the highest prevalence of HIV-infection. We examined the prevalence of depressive symptoms, using a Hopkins Symptom Checklist for Depression (HSCL-D score of ≥ 1.75 to define depression, and correlates of depression using multivariate logistic regression stratified by sex. RESULTS: Of 1,268 participants surveyed, 25.3% of women and 31.4% of men had depression. Among women, lower education (adjusted odds ratio [AOR] 2.07, 95% confidence interval [1.30-3.32], higher income (1.77 [1.09-2.86], and lack of control in sexual decision-making (2.35 [1.46-3.81] were positively associated with depression. Among men, being single (1.95 [1.02-3.74], living in a rural area (1.63 [1.02-2.65], having frequent visits to a health provider (3.29 [1.88-5.74], anticipated HIV stigma (fearing discrimination if HIV status was revealed (2.04 [1.27-3.29], and intergenerational sex (2.28 [1.17-4.41] were independently associated with depression. DISCUSSION: Depression is highly prevalent in Botswana, and its correlates are gender-specific. Our findings suggest multiple targets for screening and prevention of depression and highlight the need to integrate mental health counseling and treatment into primary health care to decrease morbidity and improve HIV management efforts.

  5. Escherichia coli–expressed near full length HIV-1 envelope glycoprotein is a highly sensitive and specific diagnostic antigen

    Directory of Open Access Journals (Sweden)

    Talha Sheikh M

    2012-11-01

    Full Text Available Abstract Background The Human Immunodeficiency Virus type 1 (HIV-1 envelope glycoprotein gp160, useful in detecting anti-HIV-1 antibodies, is difficult to express in heterologous hosts. The major hurdles are its signal sequence, strong hydrophobic regions and heavy glycosylation. While it has not been possible to express full length recombinant (r-gp160 in E. coli, it can be expressed in insect and mammalian cells, but at relatively higher cost. In this work, we report E. coli-based over-expression of r-gp160 variant and evaluate its performance in diagnostic immunoassays for the detection of anti-HIV-1 antibodies. Methods A deletion variant of r-gp160 lacking hydrophobic regions of the parent full length molecule was expressed in E. coli and purified to near homogeneity using single-step Ni(II-affinity chromatography. Biotinylated and europium(III chelate-labeled versions of this antigen were used to set up one- and two-step time-resolved fluorometric double antigen sandwich assays. The performance of these assays was evaluated against a collection of well-characterized human sera (n=131, that included an in-house panel and four commercially procured panels. Results In-frame deletion of three hydrophobic regions, spanning amino acid residues 1–43, 519–538 and 676–706, of full length HIV-1 gp160 resulted in its expression in E. coli. Both the one- and two-step assays manifested high sensitivity unambiguously identifying 75/77 and 77/77 HIV-1 positive sera, respectively. Both assays also identified all 52 HIV-seronegative sera correctly. Between the two assays, the mean signal-to-cutoff value of the two-step assay was an order of magnitude greater than that of the one-step assay. Both assays were highly specific manifesting no cross-reactivity towards antibodies specific to other viruses like hepatitis B, C, and human T cell leukemia viruses. Conclusions This study has demonstrated the expression of r-gp160 variant in E. coli, by deletion

  6. Non-peptidic propargylamines as inhibitors of lysine specific demethylase 1 (LSD1) with cellular activity

    Science.gov (United States)

    Schmitt, Martin L.; Hauser, Alexander-Thomas; Carlino, Luca; Pippel, Martin; Schulz-Fincke, Johannes; Metzger, Eric; Willmann, Dominica; Yiu, Teresa; Barton, Michelle; Schüle, Roland; Sippl, Wolfgang; Jung, Manfred

    2015-01-01

    Lysine demethylases play an important role in epigenetic regulation and thus in the development of diseases like cancer or neurodegenerative disorders. As the lysine specific demethylase 1 (LSD1/KDM1) has been strongly connected to androgen and estrogen dependent gene expression, it serves as a promising target for the therapy of hormone dependent cancer. Here, we report on the discovery of new small molecule inhibitors of LSD1 containing a propargylamine warhead, starting out from lysine containing substrate analogues. Based on these substrate mimicking inhibitors we were able to increase potency by a combination of similarity-based virtual screening and subsequent synthetic optimization resulting in more druglike LSD1 inhibitors that lead to histone hypermethylation in breast cancer cells. PMID:24007511

  7. Human Cytosolic Extracts Stabilize the HIV-1 Core

    Science.gov (United States)

    Fricke, Thomas; Brandariz-Nuñez, Alberto; Wang, Xiaozhao; Smith, Amos B.

    2013-01-01

    The stability of the HIV-1 core in the cytoplasm is crucial for productive HIV-1 infection. Mutations that stabilize or destabilize the core showed defects on HIV-1 reverse transcription and infection. We developed a novel and simple assay to measure the stability of in vitro-assembled HIV-1 CA-NC complexes. The assay allowed us to demonstrate that cytosolic extracts strongly stabilize the HIV-1 core. Interestingly, stabilization of in vitro-assembled HIV-1 CA-NC complexes is not due solely to macromolecular crowding, suggesting the presence of specific cellular factors that stabilize the HIV-1 core. By using our novel assay, we measured the abilities of different drugs, such as PF74, CAP-1, IXN-053, cyclosporine, Bi2 (also known as BI-2), and the peptide CAI, to modulate the stability of in vitro-assembled HIV-1 CA-NC complexes. Interestingly, we found that PF74 and Bi2 strongly stabilized HIV-1 CA-NC complexes. On the other hand, the peptide CAI destabilized HIV-1 CA-NC complexes. We also found that purified cyclophilin A destabilizes in vitro-assembled HIV-1 CA-NC complexes in the presence of cellular extracts in a cyclosporine-sensitive manner. In agreement with previous observations using the fate-of-the-capsid assay, we also demonstrated the ability of recombinant CPSF6 to stabilize HIV-1 CA-NC complexes. Overall, our findings suggested that cellular extracts specifically stabilize the HIV-1 core. We believe that our assay can be a powerful tool to assess HIV-1 core stability in vitro. PMID:23885082

  8. Specific VpU Codon Changes were Significantly associated with gp120 V3 Tropic Signatures in HIV-1 B-subtype

    Institute of Scientific and Technical Information of China (English)

    Salvatore Dimonte; Muhammed Babakir-Mina; Stefano Aquaro; Carlo-Federico Perno

    2012-01-01

    After infection and integration steps,HIV-1 transcriptions increase sharply and singly-spliced mRNAs are produced.These encode Env (gpl20 and gp41) and auxiliary proteins Vif,Vpr and VpU.The same localization within the unique structure of the mRNAs suggests that the VpU sequence prior to the Env could affect the Env polyprotein expression.The HIV-1 infection process begins when the gp120 subunit of the envelope glycoprotein complex interacts with its receptor(s) on the target cell.The V3 domain of gp120 is the major determinant of cellular co-receptor binding.According to phenotypic information of HIV-1 isolates,sequences from the VpU to V3 regions (119 in R5-and 120 X4-tropic viruses; oneper patient) were analysed.The binomial correlation phi coefficient was used to assess covariation among VpU and gp120v3 signatures.Subsequently,average linkage hierarchical agglomerative clustering was performed.Beyond the classical V3 signatures (R5-viruses:S11,E25D; X4-viruses:S11KR,E25KRQ),other specific V3 and novel VpU signatures were found to be statistically associated with co-receptor usage.Several statistically significant associations between V3 and VpU mutations were also observed.The dendrogram showed two distinct large clusters:one associated with R5-tropic sequences (bootstrap=0.94),involving:(a) H13NPV3,E25DV3,S11V3,T22AV3 and Q61HVpU,(b) E25AV3 and L12FVpU:,(c) D44EVpU,R18QV3 and D80NVpU; and another associated with X4-tropic sequences (bootstrap=0.97),involving:(i) E25Iv3 and V10AvpU,(ii)0-1insVVpU,H13Rv3,146LVpU,I30Mv3 and 60-62delVpU,(iii) S11KRV3 and E25KRQV3.Some of these pairs of mutations were encoded always by one specific codon.These data indicate the possible VpU mutational patterns contributing to regulation of HIV-1 tropism.

  9. Heterologous prime-boost regimens using rAd35 and rMVA vectors elicit stronger cellular immune responses to HIV proteins than homologous regimens.

    Directory of Open Access Journals (Sweden)

    Silvia Ratto-Kim

    Full Text Available We characterized prime-boost vaccine regimens using heterologous and homologous vector and gene inserts. Heterologous regimens offer a promising approach that focuses the cell-mediated immune response on the insert and away from vector-dominated responses. Ad35-GRIN/ENV (Ad35-GE vaccine is comprised of two vectors containing sequences from HIV-1 subtype A gag, rt, int, nef (Ad35-GRIN and env (Ad35-ENV. MVA-CMDR (MVA-C, MVA-KEA (MVA-K and MVA-TZC (MVA-T vaccines contain gag, env and pol genes from HIV-1 subtypes CRF01_AE, A and C, respectively. Balb/c mice were immunized with different heterologous and homologous vector and insert prime-boost combinations. HIV and vector-specific immune responses were quantified post-boost vaccination. Gag-specific IFN-γ ELISPOT, intracellular cytokine staining (ICS (CD107a, IFN-γ, TNF-α and IL-2, pentamer staining and T-cell phenotyping were used to differentiate responses to inserts and vectors. Ad35-GE prime followed by boost with any of the recombinant MVA constructs (rMVA induced CD8+ Gag-specific responses superior to Ad35-GE-Ad35-GE or rMVA-rMVA prime-boost combinations. Notably, there was a shift toward insert-focus responses using heterologous vector prime-boost regimens. Gag-specific central and effector memory T cells were generated more rapidly and in greater numbers in the heterologous compared to the homologous prime-boost regimens. These results suggest that heterologous prime-boost vaccination regimens enhance immunity by increasing the magnitude, onset and multifunctionality of the insert-specific cell-mediated immune response compared to homologous vaccination regimens. This study supports the rationale for testing heterologous prime-boost regimens in humans.

  10. Programmed death-1 expression on HIV-1-specific CD8+ T cells is shaped by epitope specificity, T-cell receptor clonotype usage and antigen load

    DEFF Research Database (Denmark)

    Kløverpris, Henrik N; McGregor, Reuben; McLaren, James E

    2014-01-01

    OBJECTIVES: Although CD8+ T cells play a critical role in the control of HIV-1 infection,their antiviral efficacy can be limited by antigenic variation and immune exhaustion.The latter phenomenon is characterized by the upregulation of multiple inhibitory receptors, such as programmed death-1 (PD-1......), CD244 and lymphocyte activation gene-3 (LAG-3), which modulate the functional capabilities of CD8+ T cells. DESIGN AND METHODS: Here, we used an array of different human leukocyte antigen(HLA)-B*15:03 and HLA-B*42:01 tetramers to characterize inhibitory receptor expression as a function...... by effector memory CD8+ T cells. CONCLUSION: Collectively, these data suggest that PD-1 expression on HIV-1-specific CD8+ T cells tracks antigen load at the level of epitope specificity and TCR clonotype usage. These findings are important because they provide evidence that PD-1 expression levels...

  11. Genetic polymorphisms associated with rubella virus-specific cellular immunity following MMR vaccination.

    Science.gov (United States)

    Kennedy, Richard B; Ovsyannikova, Inna G; Haralambieva, Iana H; Lambert, Nathaniel D; Pankratz, V Shane; Poland, Gregory A

    2014-11-01

    Rubella virus causes a relatively benign disease in most cases, although infection during pregnancy can result in serious birth defects. An effective vaccine has been available since the early 1970s and outbreaks typically do not occur among highly vaccinated (≥2 doses) populations. Nevertheless, considerable inter-individual variation in immune response to rubella immunization does exist, with single-dose seroconversion rates ~95 %. Understanding the mechanisms behind this variability may provide important insights into rubella immunity. In the current study, we examined associations between single nucleotide polymorphisms (SNPs) in selected cytokine, cytokine receptor, and innate/antiviral genes and immune responses following rubella vaccination in order to understand genetic influences on vaccine response. Our approach consisted of a discovery cohort of 887 subjects aged 11-22 at the time of enrollment and a replication cohort of 542 older adolescents and young adults (age 18-40). Our data indicate that SNPs near the butyrophilin genes (BTN3A3/BTN2A1) and cytokine receptors (IL10RB/IFNAR1) are associated with variations in IFNγ secretion and that multiple SNPs in the PVR gene, as well as SNPs located in the ADAR gene, exhibit significant associations with rubella virus-specific IL-6 secretion. This information may be useful, not only in furthering our understanding immune responses to rubella vaccine, but also in identifying key pathways for targeted adjuvant use to boost immunity in those with weak or absent immunity following vaccination.

  12. Molecular and cellular specificity of post-translational aminoacyl isomerization in the crustacean hyperglycaemic hormone family.

    Science.gov (United States)

    Ollivaux, Céline; Gallois, Dominique; Amiche, Mohamed; Boscaméric, Maryse; Soyez, Daniel

    2009-09-01

    D-aminoacyl residues have been detected in various animal peptides from several taxa, especially vertebrates and arthropods. This unusual polymorphism was shown to occur in isoforms of the crustacean hyperglycaemic hormone (CHH) of the American lobster because a D-phenylalanyl residue was found in position 3 of the sequence (CHH and D-Phe3 CHH). In the present study, we report the detailed strategy used to characterize, in the lobster neuroendocrine system, isomers of another member of the CHH family, vitellogenesis inhibiting hormone (VIH). We have demonstrated that the fourth residue is either an L- or a D- tryptophanyl residue (VIH and D-Trp4 VIH). Furthermore, use of antisera specifically recognizing the epimers of CHH and VIH reveals that aminoacyl isomerization occurs in specialized cells of the X organ-sinus gland neurosecretory system and that the D-forms of the two neuropeptides are not only present in the same cells, but, importantly, also are co-packaged within the same secretory vesicles.

  13. A global approach to HIV-1 vaccine development

    Science.gov (United States)

    Stephenson, Kathryn E; Barouch, Dan H

    2013-01-01

    Summary A global human immunodeficiency virus-1 (HIV-1) vaccine will have to elicit immune responses capable of providing protection against a tremendous diversity of HIV-1 variants. In this review, we first describe the current state of the HIV-1 vaccine field, outlining the immune responses that are desired in a global HIV-1 vaccine. In particular, we emphasize the likely importance of Env-specific neutralizing and non-neutralizing antibodies for protection against HIV-1 acquisition and the likely importance of effector Gag-specific T lymphocytes for virologic control. We then highlight four strategies for developing a global HIV-1 vaccine. The first approach is to design specific vaccines for each geographic region that include antigens tailor-made to match local circulating HIV-1 strains. The second approach is to design a vaccine that will elicit Env-specific antibodies capable of broadly neutralizing all HIV-1 subtypes. The third approach is to design a vaccine that will elicit cellular immune responses that are focused on highly conserved HIV-1 sequences. The fourth approach is to design a vaccine to elicit highly diverse HIV-1-specific responses. Finally, we emphasize the importance of conducting clinical efficacy trials as the only way to determine which strategies will provide optimal protection against HIV-1 in humans. PMID:23772627

  14. A candidate HIV/AIDS vaccine (MVA-B lacking vaccinia virus gene C6L enhances memory HIV-1-specific T-cell responses.

    Directory of Open Access Journals (Sweden)

    Juan García-Arriaza

    Full Text Available The vaccinia virus (VACV C6 protein has sequence similarities with the poxvirus family Pox_A46, involved in regulation of host immune responses, but its role is unknown. Here, we have characterized the C6 protein and its effects in virus replication, innate immune sensing and immunogenicity in vivo. C6 is a 18.2 kDa protein, which is expressed early during virus infection and localizes to the cytoplasm of infected cells. Deletion of the C6L gene from the poxvirus vector MVA-B expressing HIV-1 Env, Gag, Pol and Nef antigens from clade B (MVA-B ΔC6L had no effect on virus growth kinetics; therefore C6 protein is not essential for virus replication. The innate immune signals elicited by MVA-B ΔC6L in human macrophages and monocyte-derived dendritic cells (moDCs are characterized by the up-regulation of the expression of IFN-β and IFN-α/β-inducible genes. In a DNA prime/MVA boost immunization protocol in mice, flow cytometry analysis revealed that MVA-B ΔC6L enhanced the magnitude and polyfunctionality of the HIV-1-specific CD4+ and CD8+ T-cell memory immune responses, with most of the HIV-1 responses mediated by the CD8+ T-cell compartment with an effector phenotype. Significantly, while MVA-B induced preferentially Env- and Gag-specific CD8+ T-cell responses, MVA-B ΔC6L induced more Gag-Pol-Nef-specific CD8+ T-cell responses. Furthermore, MVA-B ΔC6L enhanced the levels of antibodies against Env in comparison with MVA-B. These findings revealed that C6 can be considered as an immunomodulator and that deleting C6L gene in MVA-B confers an immunological benefit by enhancing IFN-β-dependent responses and increasing the magnitude and quality of the T-cell memory immune responses to HIV-1 antigens. Our observations are relevant for the improvement of MVA vectors as HIV-1 vaccines.

  15. A candidate HIV/AIDS vaccine (MVA-B) lacking vaccinia virus gene C6L enhances memory HIV-1-specific T-cell responses.

    Science.gov (United States)

    García-Arriaza, Juan; Nájera, José Luis; Gómez, Carmen E; Tewabe, Nolawit; Sorzano, Carlos Oscar S; Calandra, Thierry; Roger, Thierry; Esteban, Mariano

    2011-01-01

    The vaccinia virus (VACV) C6 protein has sequence similarities with the poxvirus family Pox_A46, involved in regulation of host immune responses, but its role is unknown. Here, we have characterized the C6 protein and its effects in virus replication, innate immune sensing and immunogenicity in vivo. C6 is a 18.2 kDa protein, which is expressed early during virus infection and localizes to the cytoplasm of infected cells. Deletion of the C6L gene from the poxvirus vector MVA-B expressing HIV-1 Env, Gag, Pol and Nef antigens from clade B (MVA-B ΔC6L) had no effect on virus growth kinetics; therefore C6 protein is not essential for virus replication. The innate immune signals elicited by MVA-B ΔC6L in human macrophages and monocyte-derived dendritic cells (moDCs) are characterized by the up-regulation of the expression of IFN-β and IFN-α/β-inducible genes. In a DNA prime/MVA boost immunization protocol in mice, flow cytometry analysis revealed that MVA-B ΔC6L enhanced the magnitude and polyfunctionality of the HIV-1-specific CD4+ and CD8+ T-cell memory immune responses, with most of the HIV-1 responses mediated by the CD8+ T-cell compartment with an effector phenotype. Significantly, while MVA-B induced preferentially Env- and Gag-specific CD8+ T-cell responses, MVA-B ΔC6L induced more Gag-Pol-Nef-specific CD8+ T-cell responses. Furthermore, MVA-B ΔC6L enhanced the levels of antibodies against Env in comparison with MVA-B. These findings revealed that C6 can be considered as an immunomodulator and that deleting C6L gene in MVA-B confers an immunological benefit by enhancing IFN-β-dependent responses and increasing the magnitude and quality of the T-cell memory immune responses to HIV-1 antigens. Our observations are relevant for the improvement of MVA vectors as HIV-1 vaccines.

  16. In vitro induction of tumor-specific immunity. VI: analysis of specificity of immune response by cellular competitive inhibition: limitations and advantages of the technique.

    Science.gov (United States)

    Chism, S E; Burton, R C; Grail, D L; Bell, P M; Warner, N L

    1977-01-01

    The cellular competitive inhibition 51Cr-release assay makes two distinct contributions to the in vitro study of cell-mediated immunity. It allows target cells which are not amenable to isotopic labelling to be investigated for their antigenic specificity, and it provides a means, complementary to the direct cytotoxicity assay, of estimating qualitative and quantitative differences in antigen expression on intact normal and neoplastic cells. Various parameters of a micro-51Cr-release inhibition assay have been studied, and it was found that the assay conditions markedly influenced both the sensitivity and specificity. It is concluded that optimal assay conditions for specificity include: 1) moderate levels of lysis on the linear part of the CL/T titration curve, 2) avoidance of prolonged assay times, and 3) low ratios of blocker to target cells. When tumor cells with large cell volumes are used as competitive inhibitor (blocker) cells, non-specific blocking will occur; limits have been defined for this particular micro-inhibition assay which, in general, exclude these effects.

  17. Allele-specific Gene Silencing of Mutant mRNA Restores Cellular Function in Ullrich Congenital Muscular Dystrophy Fibroblasts

    Directory of Open Access Journals (Sweden)

    Satoru Noguchi

    2014-01-01

    Full Text Available Ullrich congenital muscular dystrophy (UCMD is an inherited muscle disorder characterized clinically by muscle weakness, distal joint hyperlaxity, and proximal joint contractures. Sporadic and recessive mutations in the three collagen VI genes, COL6A1, COL6A2, and COL6A3, are reported to be causative. In the sporadic forms, a heterozygous point mutation causing glycine substitution in the triple helical domain has been identified in higher rate. In this study, we examined the efficacy of siRNAs, which target point mutation site, on specific knockdown toward transcripts from mutant allele and evaluated consequent cellular phenotype of UCMD fibroblasts. We evaluated the effect of siRNAs targeted to silence-specific COL6A1 alleles in UCMD fibroblasts, where simultaneous expression of both wild-type and mutant collagen VI resulted in defective collagen localization. Addition of mutant-specific siRNAs allowed normal extracellular localization of collagen VI surrounding fibroblasts, suggesting selective inhibition of mutant collagen VI. Targeting the single-nucleotide COL6A1 c.850G>A (p.G284R mutation responsible a sporadic autosomal dominant form of UCMD can potently and selectively block expression of mutant collagen VI. These results suggest that allele-specific knockdown of the mutant mRNA can potentially be considered as a therapeutic procedure in UCMD due to COL6A1 point mutations.

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

    Directory of Open Access Journals (Sweden)

    Purcell Damian FJ

    2008-02-01

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

  19. HIV-Specific CD8 T Cells Producing CCL-4 Are Associated With Worse Immune Reconstitution During Chronic Infection.

    Science.gov (United States)

    Casetti, Rita; Pinnetti, Carmela; Sacchi, Alessandra; De Simone, Gabriele; Bordoni, Veronica; Cimini, Eleonora; Tumino, Nicola; Besi, Francesca; Viola, Domenico; Turchi, Federica; Mazzotta, Valentina; Antinori, Andrea; Martini, Federico; Ammassari, Adriana; Agrati, Chiara

    2017-07-01

    Immunological nonresponse represents the Achilles heel in the combination antiretroviral therapy (cART) effectiveness, and increases risk of clinical events and death. CD8 T cells play a crucial role in controlling HIV replication, and polyfunctional HIV-specific CD8 T cells have been associated with nonprogressive HIV infection. However, the possible role of polyfunctional CD8 T cells in predicting posttreatment immune reconstitution has not yet been explored. The aim of this study was to identify functional markers predictive of immunological response to cART in chronic HIV-infected patients. A cohort of chronic HIV-infected individuals naive to cART were enrolled in the ALPHA study. CD4/CD8 T-cell subsets, their differentiation/activation, as well as susceptibility to apoptosis were analyzed before and after 12 months of cART. Moreover, CD8 T cells polyfunctional response after HIV antigenic stimulation was also assessed. Results showed a significant correlation between worse CD4 T-cell restoration and low frequency of naive CD4 T cells, high frequency of effector memory CD4 T cells, and high susceptibility to apoptosis of CD4 T cells all before cART. Moreover, CD8 functional subsets expressing total C-C motif chemokine ligand 4 (CCL-4) or in combination with CD107a and interferon gamma (IFNγ) were negatively associated with immune reconstitution. In conclusion, our study shows that a more differentiated phenotype of CD4 T cells and CCL-4-producing CD8 T cells could represent valuable predictors of worse immune reconstitution. These parameters may be used as tools for identifying patients at risk of immunological failure during cART and eventually represent the basis for innovative therapeutic strategies.

  20. Preferential suppression of CXCR4-specific strains of HIV-1 by antiviral therapy.

    Science.gov (United States)

    Philpott, S; Weiser, B; Anastos, K; Kitchen, C M; Robison, E; Meyer, W A; Sacks, H S; Mathur-Wagh, U; Brunner, C; Burger, H

    2001-02-01

    To initiate infection, HIV-1 requires a primary receptor, CD4, and a secondary receptor, principally the chemokine receptor CCR5 or CXCR4. Coreceptor usage plays a critical role in HIV-1 disease progression. HIV-1 transmitted in vivo generally uses CCR5 (R5), but later CXCR4 (X4) strains may emerge; this shift heralds CD4+ cell depletion and clinical deterioration. We asked whether antiretroviral therapy can shift HIV-1 populations back to R5 viruses after X4 strains have emerged, in part because treatment has been successful in slowing disease progression without uniformly suppressing plasma viremia. We analyzed the coreceptor usage of serial primary isolates from 15 women with advanced disease who demonstrated X4 viruses. Coreceptor usage was determined by using a HOS-CD4+ cell system, biological and molecular cloning, and sequencing the envelope gene V3 region. By constructing a mathematical model to measure the proportion of virus in a specimen using each coreceptor, we demonstrated that the predominant viral population shifted from X4 at baseline to R5 strains after treatment. Multivariate analyses showed that the shift was independent of changes in plasma HIV-1 RNA level and CD4+ cell count. Hence, combination therapy may lead to a change in phenotypic character as well as in the quantity of HIV-1. Shifts in coreceptor usage may thereby contribute to the clinical efficacy of anti-HIV drugs.

  1. Mode of inhibition of HIV-1 Integrase by a C-terminal domain-specific monoclonal antibody*

    Directory of Open Access Journals (Sweden)

    Merkel George

    2006-06-01

    Full Text Available Abstract Background To further our understanding of the structure and function of HIV-1 integrase (IN we developed and characterized a library of monoclonal antibodies (mAbs directed against this protein. One of these antibodies, mAb33, which is specific for the C-terminal domain, was found to inhibit HIV-1 IN processing activity in vitro; a corresponding Fv fragment was able to inhibit HIV-1 integration in vivo. Our subsequent studies, using heteronuclear nuclear magnetic resonance spectroscopy, identified six solvent accessible residues on the surface of the C-terminal domain that were immobilized upon binding of the antibody, which were proposed to comprise the epitope. Here we test this hypothesis by measuring the affinity of mAb33 to HIV-1 proteins that contain Ala substitutions in each of these positions. To gain additional insight into the mode of inhibition we also measured the DNA binding capacity and enzymatic activities of the Ala substituted proteins. Results We found that Ala substitution of any one of five of the putative epitope residues, F223, R224, Y226, I267, and I268, caused a decrease in the affinity of the mAb33 for HIV-1 IN, confirming the prediction from NMR data. Although IN derivatives with Ala substitutions in or near the mAb33 epitope exhibited decreased enzymatic activity, none of the epitope substitutions compromised DNA binding to full length HIV-1 IN, as measured by surface plasmon resonance spectroscopy. Two of these derivatives, IN (I276A and IN (I267A/I268A, exhibited both increased DNA binding affinity and uncharacteristic dissociation kinetics; these proteins also exhibited non-specific nuclease activity. Results from these investigations are discussed in the context of current models for how the C-terminal domain interacts with substrate DNA. Conclusion It is unlikely that inhibition of HIV-1 IN activity by mAb33 is caused by direct interaction with residues that are essential for substrate binding. Rather

  2. Single Nucleotide Polymorphisms in Cellular Drug Transporters Are Associated with Intolerance to Antiretroviral Therapy in Brazilian HIV-1 Positive Individuals

    Science.gov (United States)

    Arruda, Mônica Barcellos; Campagnari, Francine; de Almeida, Tailah Bernardo; Couto-Fernandez, José Carlos; Tanuri, Amilcar; Cardoso, Cynthia Chester

    2016-01-01

    Adverse reactions are the main cause of treatment discontinuation among HIV+ individuals. Genes related to drug absorption, distribution, metabolism and excretion (ADME) influence drug bioavailability and treatment response. We have investigated the association between single nucleotide polymorphisms (SNPs) in 29 ADME genes and intolerance to therapy in a case-control study including 764 individuals. Results showed that 15 SNPs were associated with intolerance to nucleoside and 11 to non-nucleoside reverse transcriptase inhibitors (NRTIs and NNRTIs), and 8 to protease inhibitors (PIs) containing regimens under alpha = 0.05. After Bonferroni adjustment, two associations remained statistically significant. SNP rs2712816, at SLCO2B1 was associated to intolerance to NRTIs (ORGA/AA = 2.37; p = 0.0001), while rs4148396, at ABCC2, conferred risk of intolerance to PIs containing regimens (ORCT/TT = 2.64; p = 0.00009). Accordingly, haplotypes carrying rs2712816A and rs4148396T alleles were also associated to risk of intolerance to NRTIs and PIs, respectively. Our data reinforce the role of drug transporters in response to HIV therapy and may contribute to a future development of personalized therapies. PMID:27648838

  3. Transcriptome analysis reveals the contribution of thermal and the specific effects in cellular response to millimeter wave exposure.

    Science.gov (United States)

    Habauzit, Denis; Le Quément, Catherine; Zhadobov, Maxim; Martin, Catherine; Aubry, Marc; Sauleau, Ronan; Le Dréan, Yves

    2014-01-01

    Radiofrequency radiations constitute a new form of environmental pollution. Among them, millimeter waves (MMW) will be widely used in the near future for high speed communication systems. This study aimed therefore to evaluate the biocompatibility of MMW at 60 GHz. For this purpose, we used a whole gene expression approach to assess the effect of acute 60 GHz exposure on primary cultures of human keratinocytes. Controls were performed to dissociate the electromagnetic from the thermal effect of MMW. Microarray data were validated by RT-PCR, in order to ensure the reproducibility of the results. MMW exposure at 20 mW/cm2, corresponding to the maximum incident power density authorized for public use (local exposure averaged over 1 cm2), led to an increase of temperature and to a strong modification of keratinocyte gene expression (665 genes differentially expressed). Nevertheless, when temperature is artificially maintained constant, no modification in gene expression was observed after MMW exposure. However, a heat shock control did not mimic exactly the MMW effect, suggesting a slight but specific electromagnetic effect under hyperthermia conditions (34 genes differentially expressed). By RT-PCR, we analyzed the time course of the transcriptomic response and 7 genes have been validated as differentially expressed: ADAMTS6, NOG, IL7R, FADD, JUNB, SNAI2 and HIST1H1A. Our data evidenced a specific electromagnetic effect of MMW, which is associated to the cellular response to hyperthermia. This study raises the question of co-exposures associating radiofrequencies and other environmental sources of cellular stress.

  4. Transcriptome analysis reveals the contribution of thermal and the specific effects in cellular response to millimeter wave exposure.

    Directory of Open Access Journals (Sweden)

    Denis Habauzit

    Full Text Available Radiofrequency radiations constitute a new form of environmental pollution. Among them, millimeter waves (MMW will be widely used in the near future for high speed communication systems. This study aimed therefore to evaluate the biocompatibility of MMW at 60 GHz. For this purpose, we used a whole gene expression approach to assess the effect of acute 60 GHz exposure on primary cultures of human keratinocytes. Controls were performed to dissociate the electromagnetic from the thermal effect of MMW. Microarray data were validated by RT-PCR, in order to ensure the reproducibility of the results. MMW exposure at 20 mW/cm2, corresponding to the maximum incident power density authorized for public use (local exposure averaged over 1 cm2, led to an increase of temperature and to a strong modification of keratinocyte gene expression (665 genes differentially expressed. Nevertheless, when temperature is artificially maintained constant, no modification in gene expression was observed after MMW exposure. However, a heat shock control did not mimic exactly the MMW effect, suggesting a slight but specific electromagnetic effect under hyperthermia conditions (34 genes differentially expressed. By RT-PCR, we analyzed the time course of the transcriptomic response and 7 genes have been validated as differentially expressed: ADAMTS6, NOG, IL7R, FADD, JUNB, SNAI2 and HIST1H1A. Our data evidenced a specific electromagnetic effect of MMW, which is associated to the cellular response to hyperthermia. This study raises the question of co-exposures associating radiofrequencies and other environmental sources of cellular stress.

  5. Passively transmitted gp41 antibodies in babies born from HIV-1 subtype C-seropositive women: correlation between fine specificity and protection.

    Science.gov (United States)

    Diomede, L; Nyoka, S; Pastori, C; Scotti, L; Zambon, A; Sherman, G; Gray, C M; Sarzotti-Kelsoe, M; Lopalco, L

    2012-04-01

    HIV-exposed, uninfected (EUN) babies born to HIV-infected mothers are examples of natural resistance to HIV infection. In this study, we evaluated the titer and neutralizing potential of gp41-specific maternal antibodies and their correlation with HIV transmission in HIV-infected mother-child pairs. Specific gp41-binding and -neutralizing antibodies were determined in a cohort of 74 first-time mother-child pairs, of whom 40 mothers were infected with HIV subtype C. Within the infected mother cohort, 16 babies were born infected and 24 were PCR negative and uninfected at birth (i.e., exposed but uninfected). Thirty-four HIV-uninfected and HIV-unexposed mother-child pairs were included as controls. All HIV-positive mothers and their newborns showed high IgG titers to linear epitopes within the HR1 region and to the membrane-proximal (MPER) domain of gp41; most sera also recognized the disulfide loop immunodominant epitope (IDE). Antibody titers to the gp41 epitopes were significantly lower in nontransmitting mothers (P babies (P babies. Moreover, in EUN babies, epitopes overlapping the 2F5 epitope (ELDKWAS), but not the 4E10 epitope, were neutralization targets in two out of four viruses tested. Our findings highlight important epitopes in gp41 that appear to be associated with exposure without infection and would be important to consider for vaccine design.

  6. Definition of a parameter for a typical specific absorption rate under real boundary conditions of cellular phones in a GSM networkd

    Directory of Open Access Journals (Sweden)

    D. Gerhardt

    2003-01-01

    Full Text Available Using cellular phones the specific absorption rate (SAR as a physical value must observe established and internationally defined levels to guarantee human protection. To assess human protection it is necessary to guarantee safety under worst-case conditions (especially maximum transmitting power using cellular phones. To evaluate the exposure to electromagnetic fields under normal terms of use of cellular phones the limitations of the specific absorption rate must be pointed out. In a mobile radio network normal terms of use of cellular phones, i.e. in interconnection with a fixed radio transmitter of a mobile radio network, power control of the cellular phone as well as the antenna diagram regarding a head phantom are also significant for the real exposure. Based on the specific absorption rate, the antenna diagram regarding a head phantom and taking into consideration the power control a new parameter, the typical absorption rate (SARtyp, is defined in this contribution. This parameter indicates the specific absorption rate under average normal conditions of use. Constant radio link attenuation between a cellular phone and a fixed radio transmitter for all mobile models tested was assumed in order to achieve constant field strength at the receiving antenna of the fixed radio transmitter as a result of power control. The typical specific absorption rate is a characteristic physical value of every mobile model. The typical absorption rate was calculated for 16 different mobile models and compared with the absorption rate at maximum transmitting power. The results confirm the relevance of the definition of this parameter (SARtyp as opposed to the specific absorption rate as a competent and applicable method to establish the real mean exposure from a cellular phone in a mobile radio network. The typical absorption rate provides a parameter to assess electromagnetic fields of a cellular phone that is more relevant to the consumer.

  7. Screening for HIV-related PTSD: Sensitivity and specificity of the 17 ...

    African Journals Online (AJOL)

    disease, with an estimated 22.5 million HIV-positive adults and children residing in this region, and approximately 1.7 .... who indicated that they had been diagnosed with bipolar ..... Systematic review of screening instruments for adults at.

  8. Strain-specific V3 and CD4 binding site autologous HIV-1 neutralizing antibodies select neutralization-resistant viruses

    Science.gov (United States)

    Moody, M. Anthony; Gao, Feng; Gurley, Thaddeus C.; Amos, Joshua D.; Kumar, Amit; Hora, Bhavna; Marshall, Dawn J.; Whitesides, John F.; Xia, Shi-Mao; Parks, Robert; Lloyd, Krissey E.; Hwang, Kwan-Ki; Lu, Xiaozhi; Bonsignori, Mattia; Finzi, Andrés; Vandergrift, Nathan A.; Alam, S. Munir; Ferrari, Guido; Shen, Xiaoying; Tomaras, Georgia D.; Kamanga, Gift; Cohen, Myron S.; Sam, Noel E.; Kapiga, Saidi; Gray, Elin S.; Tumba, Nancy L.; Morris, Lynn; Zolla-Pazner, Susan; Gorny, Miroslaw K.; Mascola, John R.; Hahn, Beatrice; Shaw, George M.; Sodroski, Joseph G.; Liao, Hua-Xin; Montefiori, David C.; Hraber, Peter T.; Korber, Bette T.; Haynes, Barton F.

    2015-01-01

    Summary The third variable (V3) loop and the CD4 binding site (CD4bs) of the HIV-1 envelope are frequently targeted by neutralizing antibodies (nAbs) in infected individuals. In chronic infection, HIV-1 escape mutants repopulate the plasma, and V3 and CD4bs nAbs emerge that can neutralize heterologous tier 1 easy-to-neutralize, but not tier 2 difficult-to-neutralize HIV-1 isolates. However, neutralization sensitivity of autologous plasma viruses to this type of nAb response has not been studied. We describe the development and evolution in vivo of antibodies distinguished by their target specificity for V3and CD4bs epitopes on autologous tier 2 viruses but not on heterologous tier 2 viruses. A surprisingly high fraction of autologous circulating viruses was sensitive to these antibodies. These findings demonstrate a role for V3 and CD4bs antibodies in constraining the native envelope trimer in vivo to a neutralization-resistant phenotype, explaining why HIV-1 transmission generally occurs by tier 2 neutralization-resistant viruses. PMID:26355218

  9. Cause-specific excess mortality in siblings of patients co-infected with HIV and hepatitis C virus

    DEFF Research Database (Denmark)

    Hansen, Ann-Brit Eg; Lohse, Nicolai; Gerstoft, Jan

    2007-01-01

    as underlying cause of death. Siblings of HIV-mono-infected individuals had an all-cause EMR of 0.60 (0.16-1.05) compared with siblings of controls. This modest excess mortality was due to deaths from an unknown cause [EMR = 0.28 (0.07-0.48)], deaths from substance abuse [EMR = 0.19 (-0.04-0.43)], and unnatural......BACKGROUND: Co-infection with hepatitis C in HIV-infected individuals is associated with 3- to 4-fold higher mortality among these patients' siblings, compared with siblings of mono-infected HIV-patients or population controls. This indicates that risk factors shared by family members partially...... account for the excess mortality of HIV/HCV-co-infected patients. We aimed to explore the causes of death contributing to the excess sibling mortality. METHODOLOGY AND PRINCIPAL FINDINGS: We retrieved causes of death from the Danish National Registry of Deaths and estimated cause-specific excess mortality...

  10. Species-specific activity of SIV Nef and HIV-1 Vpu in overcoming restriction by tetherin/BST2.

    Directory of Open Access Journals (Sweden)

    Bin Jia

    2009-05-01

    Full Text Available Tetherin, also known as BST2, CD317 or HM1.24, was recently identified as an interferon-inducible host-cell factor that interferes with the detachment of virus particles from infected cells. HIV-1 overcomes this restriction by expressing an accessory protein, Vpu, which counteracts tetherin. Since lentiviruses of the SIV(smm/mac/HIV-2 lineage do not have a vpu gene, this activity has likely been assumed by other viral gene products. We found that deletion of the SIV(mac239 nef gene significantly impaired virus release in cells expressing rhesus macaque tetherin. Virus release could be restored by expressing Nef in trans. However, Nef was unable to facilitate virus release in the presence of human tetherin. Conversely, Vpu enhanced virus release in the presence of human tetherin, but not in the presence of rhesus tetherin. In accordance with the species-specificity of Nef in mediating virus release, SIV Nef downregulated cell-surface expression of rhesus tetherin, but did not downregulate human tetherin. The specificity of SIV Nef for rhesus tetherin mapped to four amino acids in the cytoplasmic domain of the molecule that are missing from human tetherin, whereas the specificity of Vpu for human tetherin mapped to amino acid differences in the transmembrane domain. Nef alleles of SIV(smm, HIV-2 and HIV-1 were also able to rescue virus release in the presence of both rhesus macaque and sooty mangabey tetherin, but were generally ineffective against human tetherin. Thus, the ability of Nef to antagonize tetherin from these Old World primates appears to be conserved among the primate lentiviruses. These results identify Nef as the viral gene product of SIV that opposes restriction by tetherin in rhesus macaques and sooty mangabeys, and reveal species-specificity in the activities of both Nef and Vpu in overcoming tetherin in their respective hosts.

  11. HIV-1 specific antibody titers and neutralization among chronically infected patients on long-term suppressive antiretroviral therapy (ART: a cross-sectional study.

    Directory of Open Access Journals (Sweden)

    Johannes S Gach

    Full Text Available The majority of potent and broadly neutralizing antibodies against HIV-1 have been isolated from untreated patients with acute or chronic infection. To assess the extent of HIV-1 specific antibody response and neutralization after many years of virologic suppression from potent combination ART, we examined antibody binding titers and neutralization of 51 patients with chronic HIV-1 infection on suppressive ART for at least three years. In this cross-sectional analysis, we found high antibody titers against gp120, gp41, and the membrane proximal external region (MPER in 59%, 43%, and 27% of patients, respectively. We observed significantly higher endpoint binding titers for gp120 and gp41 for patients with >10 compared to ≤ 10 years of detectable HIV RNA. Additionally, we observed higher median gp120 and gp41 antibody titers in patients with HIV RNA 10 years of detectable HIV RNA (8/20 [40.0%] versus 3/31 [9.7%] for ≤ 10 years, p = 0.02 and a trend toward greater neutralization in patients with ≤ 5 years of HIV RNA 5 years, p = 0.08. All patients with neutralizing activity mediated successful phagocytosis of VLPs by THP-1 cells after antibody opsonization. Our findings of highly specific antibodies to several structural epitopes of HIV-1 with antibody effector functions and neutralizing activity after long-term suppressive ART, suggest continuous antigenic stimulation and evolution of HIV-specific antibody response occurs before and after suppression with ART. These patients, particularly those with slower HIV progression and more time with detectable viremia prior to initiation of suppressive ART, are a promising population to identify and further study functional antibodies against HIV-1.

  12. Quantification of IgA and IgG and specificities of antibodies to viral proteins in parotid saliva at different stages of HIV-1 infection

    Science.gov (United States)

    CARTRY, O; MOJA, P; QUESNEL, A; POZZETTO, B; LUCHT, F R; GENIN, C

    1997-01-01

    Paired sera and parotid saliva from 75 HIV-1-infected patients, divided in three equal groups with CD4+ cell counts > 500, 200–500 and < 200/mm3, respectively, were analysed for IgG, IgA and secretory IgA (sIgA) concentrations and for IgG and IgA antibody directed to HIV-1. Twenty-nine age-matched HIV− subjects were used as controls. In serum the concentrations of immunoglobulins were significantly increased in HIV-infected subjects compared with controls, and a progressive increase of IgA and sIgA was noticed while the CD4+ cell count decreased. In contrast, concentrations of IgA and sIgA were not different in parotid saliva between the four subject groups. By an ELISA test directed towards HIV-1 proteins, 73 of the 75 serum specimens from the HIV-infected subjects (97%) and 43 of the corresponding saliva (57%) were found positive for specific IgA antibodies to HIV-1, with an even distribution among the three groups of patients. By Western blotting multiple specificities of IgA to HIV-1 proteins were not frequently found in patients. By contrast, in spite of an IgG concentration in saliva about 100 times lower than that of IgA, reactivities were significantly higher for IgG than for IgA antibodies, especially to env and to pol HIV-1 products. Altogether, these data suggest that the regulation of IgA production in HIV-infected subjects is independent in serum and in parotid saliva. This imbalance of IgA/IgG antibodies to HIV-1 at the mucosal level appears to be a specific feature of HIV-1 infection, and may raise important issues in terms of local protection after immunization. PMID:9218823

  13. Modification to the capsid of the adenovirus vector that enhances dendritic cell infection and transgene-specific cellular immune responses.

    Science.gov (United States)

    Worgall, Stefan; Busch, Annette; Rivara, Michael; Bonnyay, David; Leopold, Philip L; Merritt, Robert; Hackett, Neil R; Rovelink, Peter W; Bruder, Joseph T; Wickham, Thomas J; Kovesdi, Imi; Crystal, Ronald G

    2004-03-01

    Adenovirus (Ad) gene transfer vectors can be used to transfer and express antigens and function as strong adjuvants and thus are useful platforms for the development of genetic vaccines. Based on the hypothesis that Ad vectors with enhanced infectibility of dendritic cells (DC) may be able to evoke enhanced immune responses against antigens encoded by the vector in vivo, the present study analyzes the vaccine potential of an Ad vector expressing beta-galactosidase as a model antigen and genetically modified with RGD on the fiber knob [AdZ.F(RGD)] to more selectively infect DC and consequently enhance immunity against the beta-galactosidase antigen. Infection of murine DC in vitro with AdZ.F(RGD) showed an eightfold-increased transgene expression following infection compared to AdZ (also expressing beta-galactosidase, but with a wild-type capsid). Binding, cellular uptake, and trafficking in DC were also increased with AdZ.F(RGD) compared to AdZ. To determine whether AdZ.F(RGD) could evoke enhanced immune responses to beta-galactosidase in vivo, C57BL/6 mice were immunized with AdZ.F(RGD) or AdZ subcutaneously via the footpad. Humoral responses with both vectors were comparable, with similar anti-beta-galactosidase antibody levels following vector administration. However, cellular responses to beta-galactosidase were significantly enhanced, with the frequency of CD4(+) as well as the CD8(+) beta-galactosidase-specific gamma interferon response in cells isolated from the draining lymph nodes increased following immunization with AdZ.F(RGD) compared to Ad.Z (P AdZ.F(RGD) vector was sufficient to evoke enhanced inhibition of the growth of preexisting tumors expressing beta-galactosidase: BALB/c mice implanted with the CT26 syngeneic beta-galactosidase-expressing colon carcinoma cell line and subsequently immunized with AdZ.F(RGD) showed decreased tumor growth and improved survival compared to mice immunized with AdZ. These data demonstrate that addition of an RGD motif

  14. Conserved Interaction of Lentiviral Vif Molecules with HIV-1 Gag and Differential Effects of Species-Specific Vif on Virus Production.

    Science.gov (United States)

    Zheng, Wenwen; Ling, Limian; Li, Zhaolong; Wang, Hong; Rui, Yajuan; Gao, Wenying; Wang, Shaohua; Su, Xing; Wei, Wei; Yu, Xiao-Fang

    2017-04-01

    The virion infectivity factor (Vif) open reading frame is conserved among most lentiviruses. Vif molecules contribute to viral replication by inactivating host antiviral factors, the APOBEC3 cytidine deaminases. However, various species of lentiviral Vif proteins have evolved different strategies for overcoming host APOBEC3. Whether different species of lentiviral Vif proteins still preserve certain common features has not been reported. Here, we show for the first time that diverse lentiviral Vif molecules maintain the ability to interact with the human immunodeficiency virus type 1 (HIV-1) Gag precursor (Pr55(Gag)) polyprotein. Surprisingly, bovine immunodeficiency virus (BIV) Vif, but not HIV-1 Vif, interfered with HIV-1 production and viral infectivity even in the absence of APOBEC3. Further analysis revealed that BIV Vif demonstrated an enhanced interaction with Pr55(Gag) compared to that of HIV-1 Vif, and BIV Vif defective for the Pr55(Gag) interaction lost its ability to inhibit HIV-1. The C-terminal region of capsid (CA) and the p2 region of Pr55(Gag), which are important for virus assembly and maturation, were involved in the interaction. Transduction of CD4(+) T cells with BIV Vif blocked HIV-1 replication. Thus, the conserved Vif-Pr55(Gag) interaction provides a potential target for the future development of antiviral strategies.IMPORTANCE The conserved Vif accessory proteins of primate lentiviruses HIV-1, simian immunodeficiency virus (SIV), and BIV all form ubiquitin ligase complexes to target host antiviral APOBEC3 proteins for degradation, with different cellular requirements and using different molecular mechanisms. Here, we demonstrate that BIV Vif can interfere with HIV-1 Gag maturation and suppress HIV-1 replication through interaction with the precursor of the Gag (Pr55(Gag)) of HIV-1 in virus-producing cells. Moreover, the HIV-1 and SIV Vif proteins are conserved in terms of their interactions with HIV-1 Pr55(Gag) although HIV-1 Vif proteins

  15. Cellular source-specific effects of apolipoprotein (apo) E4 on dendrite arborization and dendritic spine development.

    Science.gov (United States)

    Jain, Sachi; Yoon, Seo Yeon; Leung, Laura; Knoferle, Johanna; Huang, Yadong

    2013-01-01

    Apolipoprotein (apo) E4 is the leading genetic risk factor for Alzheimer's disease (AD), and it has a gene dose-dependent effect on the risk and age of onset of AD. Although apoE4 is primarily produced by astrocytes in the brain, neurons can also produce apoE4 under stress conditions. ApoE4 is known to inhibit neurite outgrowth and spine development in vitro and in vivo, but the potential influence of apoE4's cellular source on dendritic arborization and spine development has not yet been investigated. In this study, we report impairments in dendritic arborization and a loss of spines, especially thin (learning) and mushroom (memory) spines, in the hippocampus and entorhinal cortex of 19-21-month-old female neuron-specific-enolase (NSE)-apoE4 and apoE4-knockin (KI) mice compared to their respective apoE3-expressing counterparts. In general, NSE-apoE4 mice had more severe and widespread deficits in dendritic arborization as well as spine density and morphology than apoE4-KI mice. The loss of dendritic spines, especially mushroom spines, occurred in NSE-apoE4 mice as early as 7-8 months of age. In contrast, glial fibrillary acidic protein (GFAP)-apoE4 mice, which express apoE4 solely in astrocytes, did not have impairments in their dendrite arborization or spine density and morphology compared to GFAP-apoE3 mice at both ages. These results indicate that the effects of apoE4 on dendrite arborization, spine density, and spine morphology depend critically on its cellular source, with neuronal apoE4 having more detrimental effects than astrocytic apoE4.

  16. Knockdown of the fat mass and obesity gene disrupts cellular energy balance in a cell-type specific manner.

    Science.gov (United States)

    Pitman, Ryan T; Fong, Jason T; Billman, Penny; Puri, Neelu

    2012-01-01

    Recent studies suggest that FTO variants strongly correlate with obesity and mainly influence energy intake with little effect on the basal metabolic rate. We suggest that FTO influences eating behavior by modulating intracellular energy levels and downstream signaling mechanisms which control energy intake and metabolism. Since FTO plays a particularly important role in adipocytes and in hypothalamic neurons, SH-SY5Y neuronal cells and 3T3-L1 adipocytes were used to understand how siRNA mediated knockdown of FTO expression alters cellular energy homeostasis. Cellular energy status was evaluated by measuring ATP levels using a luminescence assay and uptake of fluorescent glucose. FTO siRNA in SH-SY5Y cells mediated mRNA knockdown (-82%), increased ATP concentrations by up to 46% (P = 0.013) compared to controls, and decreased phosphorylation of AMPk and Akt in SH-SY5Y by -52% and -46% respectively as seen by immunoblotting. In contrast, FTO siRNA in 3T3-L1 cells decreased ATP concentration by -93% (penergy levels in a cell-type specific manner. Furthermore, glucose uptake was decreased in both SH-SY5Y (-51% p = 0.015) and 3T3-L1 cells (-30%, p = 0.0002). We also show that FTO knockdown decreases NPY mRNA expression in SH-SY5Y cells (-21%) through upregulation of pSTAT3 (118%). These results provide important evidence that FTO-variant linked obesity may be associated with altered metabolic functions through activation of downstream metabolic mediators including AMPk.

  17. Knockdown of the fat mass and obesity gene disrupts cellular energy balance in a cell-type specific manner.

    Directory of Open Access Journals (Sweden)

    Ryan T Pitman

    Full Text Available Recent studies suggest that FTO variants strongly correlate with obesity and mainly influence energy intake with little effect on the basal metabolic rate. We suggest that FTO influences eating behavior by modulating intracellular energy levels and downstream signaling mechanisms which control energy intake and metabolism. Since FTO plays a particularly important role in adipocytes and in hypothalamic neurons, SH-SY5Y neuronal cells and 3T3-L1 adipocytes were used to understand how siRNA mediated knockdown of FTO expression alters cellular energy homeostasis. Cellular energy status was evaluated by measuring ATP levels using a luminescence assay and uptake of fluorescent glucose. FTO siRNA in SH-SY5Y cells mediated mRNA knockdown (-82%, increased ATP concentrations by up to 46% (P = 0.013 compared to controls, and decreased phosphorylation of AMPk and Akt in SH-SY5Y by -52% and -46% respectively as seen by immunoblotting. In contrast, FTO siRNA in 3T3-L1 cells decreased ATP concentration by -93% (p<0.0005, and increased AMPk and Akt phosphorylation by 204% and 70%, respectively suggesting that FTO mediates control of energy levels in a cell-type specific manner. Furthermore, glucose uptake was decreased in both SH-SY5Y (-51% p = 0.015 and 3T3-L1 cells (-30%, p = 0.0002. We also show that FTO knockdown decreases NPY mRNA expression in SH-SY5Y cells (-21% through upregulation of pSTAT3 (118%. These results provide important evidence that FTO-variant linked obesity may be associated with altered metabolic functions through activation of downstream metabolic mediators including AMPk.

  18. Cellular source-specific effects of apolipoprotein (apo E4 on dendrite arborization and dendritic spine development.

    Directory of Open Access Journals (Sweden)

    Sachi Jain

    Full Text Available Apolipoprotein (apo E4 is the leading genetic risk factor for Alzheimer's disease (AD, and it has a gene dose-dependent effect on the risk and age of onset of AD. Although apoE4 is primarily produced by astrocytes in the brain, neurons can also produce apoE4 under stress conditions. ApoE4 is known to inhibit neurite outgrowth and spine development in vitro and in vivo, but the potential influence of apoE4's cellular source on dendritic arborization and spine development has not yet been investigated. In this study, we report impairments in dendritic arborization and a loss of spines, especially thin (learning and mushroom (memory spines, in the hippocampus and entorhinal cortex of 19-21-month-old female neuron-specific-enolase (NSE-apoE4 and apoE4-knockin (KI mice compared to their respective apoE3-expressing counterparts. In general, NSE-apoE4 mice had more severe and widespread deficits in dendritic arborization as well as spine density and morphology than apoE4-KI mice. The loss of dendritic spines, especially mushroom spines, occurred in NSE-apoE4 mice as early as 7-8 months of age. In contrast, glial fibrillary acidic protein (GFAP-apoE4 mice, which express apoE4 solely in astrocytes, did not have impairments in their dendrite arborization or spine density and morphology compared to GFAP-apoE3 mice at both ages. These results indicate that the effects of apoE4 on dendrite arborization, spine density, and spine morphology depend critically on its cellular source, with neuronal apoE4 having more detrimental effects than astrocytic apoE4.

  19. In vivo platforms for analysis of HIV persistence and eradication.

    Science.gov (United States)

    Garcia, J Victor

    2016-02-01

    HIV persistence in patients undergoing antiretroviral therapy is a major impediment to the cure of HIV/AIDS. The molecular and cellular mechanisms underlying HIV persistence in vivo have not been fully elucidated. This lack of basic knowledge has hindered progress in this area. The in vivo analysis of HIV persistence and the implementation of curative strategies would benefit from animal models that accurately recapitulate key aspects of the human condition. This Review summarizes the contribution that humanized mouse models of HIV infection have made to the field of HIV cure research. Even though these models have been shown to be highly informative in many specific areas, their great potential to serve as excellent platforms for discovery in HIV pathogenesis and treatment has yet to be fully developed.

  20. Efficient and specific internal cleavage of a retroviral palindromic DNA sequence by tetrameric HIV-1 integrase.

    Directory of Open Access Journals (Sweden)

    Olivier Delelis

    Full Text Available BACKGROUND: HIV-1 integrase (IN catalyses the retroviral integration process, removing two nucleotides from each long terminal repeat and inserting the processed viral DNA into the target DNA. It is widely assumed that the strand transfer step has no sequence specificity. However, recently, it has been reported by several groups that integration sites display a preference for palindromic sequences, suggesting that a symmetry in the target DNA may stabilise the tetrameric organisation of IN in the synaptic complex. METHODOLOGY/PRINCIPAL FINDINGS: We assessed the ability of several palindrome-containing sequences to organise tetrameric IN and investigated the ability of IN to catalyse DNA cleavage at internal positions. Only one palindromic sequence was successfully cleaved by IN. Interestingly, this symmetrical sequence corresponded to the 2-LTR junction of retroviral DNA circles-a palindrome similar but not identical to the consensus sequence found at integration sites. This reaction depended strictly on the cognate retroviral sequence of IN and required a full-length wild-type IN. Furthermore, the oligomeric state of IN responsible for this cleavage differed from that involved in the 3'-processing reaction. Palindromic cleavage strictly required the tetrameric form, whereas 3'-processing was efficiently catalysed by a dimer. CONCLUSIONS/SIGNIFICANCE: Our findings suggest that the restriction-like cleavage of palindromic sequences may be a general physiological activity of retroviral INs and that IN tetramerisation is strongly favoured by DNA symmetry, either at the target site for the concerted integration or when the DNA contains the 2-LTR junction in the case of the palindromic internal cleavage.

  1. Combination of anti-retroviral drugs and radioimmunotherapy specifically kills infected cells from HIV infected individuals

    Directory of Open Access Journals (Sweden)

    Dina Tsukrov

    2016-09-01

    Full Text Available Eliminating virally infected cells is an essential component of any HIV eradication strategy. Radioimmunotherapy (RIT, a clinically established method for killing cells using radiolabeled antibodies, was recently applied to target HIV-1 gp41 antigen expressed on the surface of infect-ed cells. Since gp41 expression by infected cells is likely down-regulated in patients on an-tiretroviral therapy (ART, we evaluated the ability of RIT to kill ART-treated infected cells us-ing both in vitro models and lymphocytes isolated from HIV-infected subjects. Human peripheral blood mononuclear cells (PBMCs were infected with HIV and cultured in the presence of two clinically relevant ART combinations. Scatchard analysis of the 2556 human monoclonal anti-body to HIV gp41 binding to the infected and ART-treated cells demonstrated sufficient residual expression of gp41 on the cell surface to warrant subsequent RIT. This is the first time the quantification of gp41 post-ART is being reported. Cells were then treated with Bismuth-213-labeled 2556 antibody. conjugated to the human monoclonal antibody 2556, which binds to HIV gp41. Cell survival was quantified by Trypan blue and residual viremia by p24 ELISA. Cell surface gp41 expression was assessed by Scatchard analysis. The experiments were repeated using PBMCs isolated from blood specimens obtained from 15 HIV-infected individuals: ten on ART and five ART-naive. We found that 213Bi-2556 killed ART-treated infected PBMCs and reduced viral production to undetectable levels. ART and RIT co-treatment was more effective at reducing viral load in vitro than either therapy alone, indicating that gp41 expression under ART was sufficient to allow 213Bi-2556 to deliver cytocidal doses of radiation to infected cells. This study provides proof of concept that 213Bi-2556 may represent an innovative and effective targeting method for killing HIV-infected cells treated with ART, and supports continued development of 213Bi

  2. Plasmodium falciparum synthetic LbL microparticle vaccine elicits protective neutralizing antibody and parasite-specific cellular immune responses.

    Science.gov (United States)

    Powell, Thomas J; Tang, Jie; Derome, Mary E; Mitchell, Robert A; Jacobs, Andrea; Deng, Yanhong; Palath, Naveen; Cardenas, Edwin; Boyd, James G; Nardin, Elizabeth

    2013-04-01

    Epitopes of the circumsporozoite (CS) protein of Plasmodium falciparum, the most pathogenic species of the malaria parasite, have been shown to elicit protective immunity in experimental animals and human volunteers. The mechanisms of immunity include parasite-neutralizing antibodies that can inhibit parasite motility in the skin at the site of infection and in the bloodstream during transit to the hepatocyte host cell and also block interaction with host cell receptors on hepatocytes. In addition, specific CD4+ and CD8+ cellular mechanisms target the intracellular hepatic forms, thus preventing release of erythrocytic stage parasites from the infected hepatocyte and the ensuing blood stage cycle responsible for clinical disease. An innovative method for producing particle vaccines, layer-by-layer (LbL) fabrication of polypeptide films on solid CaCO3 cores, was used to produce synthetic malaria vaccines containing a tri-epitope CS peptide T1BT comprising the antibody epitope of the CS repeat region (B) and two T-cell epitopes, the highly conserved T1 epitope and the universal epitope T. Mice immunized with microparticles loaded with T1BT peptide developed parasite-neutralizing antibodies and malaria-specific T-cell responses including cytotoxic effector T-cells. Protection from liver stage infection following challenge with live sporozoites from infected mosquitoes correlated with neutralizing antibody levels. Although some immunized mice with low or undetectable neutralizing antibodies were also protected, depletion of T-cells prior to challenge resulted in the majority of mice remaining resistant to challenge. In addition, mice immunized with microparticles bearing only T-cell epitopes were not protected, demonstrating that cellular immunity alone was not sufficient for protective immunity. Although the microparticles without adjuvant were immunogenic and protective, a simple modification with the lipopeptide TLR2 agonist Pam3Cys increased the potency and

  3. Inhibition of microtubules and dynein rescues human immunodeficiency virus type 1 from owl monkey TRIMCyp-mediated restriction in a cellular context-specific fashion.

    Science.gov (United States)

    Pawlica, Paulina; Dufour, Caroline; Berthoux, Lionel

    2015-04-01

    IFN-induced restriction factors can significantly affect the replicative capacity of retroviruses in mammals. TRIM5α (tripartite motif protein 5, isoform α) is a restriction factor that acts at early stages of the virus life cycle by intercepting and destabilizing incoming retroviral cores. Sensitivity to TRIM5α maps to the N-terminal domain of the retroviral capsid proteins. In several New World and Old World monkey species, independent events of retrotransposon-mediated insertion of the cyclophilin A (CypA)-coding sequence in the trim5 gene have given rise to TRIMCyp (also called TRIM5-CypA), a hybrid protein that is active against some lentiviruses in a species-specific fashion. In particular, TRIMCyp from the owl monkey (omkTRIMCyp) very efficiently inhibits human immunodeficiency virus type 1 (HIV-1). Previously, we showed that disrupting the integrity of microtubules (MTs) and of cytoplasmic dynein complexes partially rescued replication of retroviruses, including HIV-1, from restriction mediated by TRIM5α. Here, we showed that efficient restriction of HIV-1 by omkTRIMCyp was similarly dependent on the MT network and on dynein complexes, but in a context-dependent fashion. When omkTRIMCyp was expressed in human HeLa cells, restriction was partially counteracted by pharmacological agents targeting MTs or by small interfering RNA-mediated inhibition of dynein. The same drugs (nocodazole and paclitaxel) also rescued HIV-1 from restriction in cat CRFK cells, although to a lesser extent. Strikingly, neither nocodazole, paclitaxel nor depletion of the dynein heavy chain had a significant effect on the restriction of HIV-1 in an owl monkey cell line. These results suggested the existence of cell-specific functional interactions between MTs/dynein and TRIMCyp. © 2015 The Authors.

  4. Dried blood spots for the diagnosis and quantitation of HIV-1: stability studies and evaluation of sensitivity and specificity for the diagnosis of infant HIV-1 infection in Thailand.

    Science.gov (United States)

    Leelawiwat, W; Young, N L; Chaowanachan, T; Ou, C Y; Culnane, M; Vanprapa, N; Waranawat, N; Wasinrapee, P; Mock, P A; Tappero, J; McNicholl, J M

    2009-02-01

    Molecular methods for HIV-1 infection using dried blood-spot (DBS) for HIV-1 CRF01_AE subtypes have not been fully optimized. In this study assays for HIV-1 diagnosis or quantitation were evaluated using infant DBS from Thailand. Paired DBS and whole blood samples from 56 HIV-1 CRF01_AE or B'-infected infants were tested for infant diagnosis using modified Amplicor DNA PCR and NucliSens RNA NASBA and an in-house real-time PCR assay. The Amplicor Monitor viral load (VL) assay, with modifications for DBS, was also evaluated. DBS VL were hematocrit corrected. Stability studies were done on DBS stored at -70 degrees C to 37 degrees C for up to 1 year. The DBS diagnostic assays were 96-100% sensitive and 100% specific for HIV-1 diagnosis. DBS HIV-1 VL were highly correlated with plasma VL when corrected using the actual or an assumed hematocrit factor (r(c)=0.88 or 0.93, respectively). HIV-1 DNA in DBS appeared to be more stable than RNA and could be detected after up to 9 months at most temperatures. DBS VL could be consistently determined when stored frozen. These results show that DBS can be used accurately instead of whole blood for the diagnosis of HIV-1 infection and VL quantitation, particularly if samples are appropriately stored.

  5. Structural basis of clade-specific HIV-1 neutralization by humanized anti-V3 monoclonal antibody KD-247.

    Science.gov (United States)

    Kirby, Karen A; Ong, Yee Tsuey; Hachiya, Atsuko; Laughlin, Thomas G; Chiang, Leslie A; Pan, Yun; Moran, Jennifer L; Marchand, Bruno; Singh, Kamalendra; Gallazzi, Fabio; Quinn, Thomas P; Yoshimura, Kazuhisa; Murakami, Toshio; Matsushita, Shuzo; Sarafianos, Stefan G

    2015-01-01

    Humanized monoclonal antibody KD-247 targets the Gly(312)-Pro(313)-Gly(314)-Arg(315) arch of the third hypervariable (V3) loop of the HIV-1 surface glycoprotein. It potently neutralizes many HIV-1 clade B isolates, but not of other clades. To understand the molecular basis of this specificity, we solved a high-resolution (1.55 Å) crystal structure of the KD-247 antigen binding fragment and examined the potential interactions with various V3 loop targets. Unlike most antibodies, KD-247 appears to interact with its target primarily through light chain residues. Several of these interactions involve Arg(315) of the V3 loop. To evaluate the role of light chain residues in the recognition of the V3 loop, we generated 20 variants of KD-247 single-chain variable fragments with mutations in the antigen-binding site. Purified proteins were assessed for V3 loop binding using AlphaScreen technology and for HIV-1 neutralization. Our data revealed that recognition of the clade-specificity defining residue Arg(315) of the V3 loop is based on a network of interactions that involve Tyr(L32), Tyr(L92), and Asn(L27d) that directly interact with Arg(315), thus elucidating the molecular interactions of KD-247 with its V3 loop target.

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

    Directory of Open Access Journals (Sweden)

    Littman Dan R

    2009-01-01

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

  7. Development of an HIV-1 specific microbicide using Caulobacter crescentus S-layer mediated display of CD4 and MIP1alpha.

    Directory of Open Access Journals (Sweden)

    John F Nomellini

    Full Text Available The development of alternative strategies to prevent HIV infection is a global public health priority. Initial efforts in anti-HIV microbicide development have met with poor success as the strategies have relied on a non-specific mechanism of action. Here, we report the development of a microbicide aimed at specifically blocking HIV entry by displaying molecular components of the HIV/host cell attachment complex on the surface of Caulobacter crescentus, a harmless aquatic bacterium. This bacterium can be readily manipulated to present heterologous proteins at high density on its surface by genetic insertion into its crystalline surface layer protein. In separate constructions, we generated bacteria displaying domain 1 of CD4 and MIP1alpha. Each moiety reacted with specific antibodies by Western immunoblot and immuno-fluorescence microscopy. Microbicide functionality was assessed using an HIV pseudotype virus assay system representing Clade B subtypes. Bacteria displaying MIP1alpha reduced infectivity by 35-78% depending on the specific subtype while CD4 display reduced infection by as much as 56%. Combinations of both constructs reduced infectivity by nearly 98%. We demonstrated that HIV infection could be inhibited using a strategy aimed at HIV-specific molecular interactions with Caulobacter surface protein display, and that sufficient protein folding and conformation could be mimicked to bind and block entry. Further, this is the first demonstration that Caulobacter surface protein display may be a useful approach to preventing HIV infection or other viruses as a microbicide. We propose that this harmless bacterium, which is inexpensive to produce and formulate, might be suitable for topical applications as a viable alternative in the search for effective microbicides to counteract the world wide incidence of HIV infection.

  8. Proteomic analysis of HIV-1 Nef cellular binding partners reveals a role for exocyst complex proteins in mediating enhancement of intercellular nanotube formation

    Directory of Open Access Journals (Sweden)

    Mukerji Joya

    2012-06-01

    Full Text Available Abstract Background HIV-1 Nef protein contributes to pathogenesis via multiple functions that include enhancement of viral replication and infectivity, alteration of intracellular trafficking, and modulation of cellular signaling pathways. Nef stimulates formation of tunneling nanotubes and virological synapses, and is transferred to bystander cells via these intercellular contacts and secreted microvesicles. Nef associates with and activates Pak2, a kinase that regulates T-cell signaling and actin cytoskeleton dynamics, but how Nef promotes nanotube formation is unknown. Results To identify Nef binding partners involved in Pak2-association dependent Nef functions, we employed tandem mass spectrometry analysis of Nef immunocomplexes from Jurkat cells expressing wild-type Nef or Nef mutants defective for the ability to associate with Pak2 (F85L, F89H, H191F and A72P, A75P in NL4-3. We report that wild-type, but not mutant Nef, was associated with 5 components of the exocyst complex (EXOC1, EXOC2, EXOC3, EXOC4, and EXOC6, an octameric complex that tethers vesicles at the plasma membrane, regulates polarized exocytosis, and recruits membranes and proteins required for nanotube formation. Additionally, Pak2 kinase was associated exclusively with wild-type Nef. Association of EXOC1, EXOC2, EXOC3, and EXOC4 with wild-type, but not mutant Nef, was verified by co-immunoprecipitation assays in Jurkat cells. Furthermore, shRNA-mediated depletion of EXOC2 in Jurkat cells abrogated Nef-mediated enhancement of nanotube formation. Using bioinformatic tools, we visualized protein interaction networks that reveal functional linkages between Nef, the exocyst complex, and the cellular endocytic and exocytic trafficking machinery. Conclusions Exocyst complex proteins are likely a key effector of Nef-mediated enhancement of nanotube formation, and possibly microvesicle secretion. Linkages revealed between Nef and the exocyst complex suggest a new paradigm of

  9. Structural basis for drug and substrate specificity exhibited by FIV encoding a chimeric FIV/HIV protease

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Ying-Chuan; Perryman, Alexander L.; Olson, Arthur J.; Torbett, Bruce E.; Elder, John H.; Stout, C. David, E-mail: dave@scripps.edu [The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037 (United States)

    2011-06-01

    Crystal structures of the 6s-98S FIV protease chimera with darunavir and lopinavir bound have been determined at 1.7 and 1.8 Å resolution, respectively. A chimeric feline immunodeficiency virus (FIV) protease (PR) has been engineered that supports infectivity but confers sensitivity to the human immunodeficiency virus (HIV) PR inhibitors darunavir (DRV) and lopinavir (LPV). The 6s-98S PR has five replacements mimicking homologous residues in HIV PR and a sixth which mutated from Pro to Ser during selection. Crystal structures of the 6s-98S FIV PR chimera with DRV and LPV bound have been determined at 1.7 and 1.8 Å resolution, respectively. The structures reveal the role of a flexible 90s loop and residue 98 in supporting Gag processing and infectivity and the roles of residue 37 in the active site and residues 55, 57 and 59 in the flap in conferring the ability to specifically recognize HIV PR drugs. Specifically, Ile37Val preserves tertiary structure but prevents steric clashes with DRV and LPV. Asn55Met and Val59Ile induce a distinct kink in the flap and a new hydrogen bond to DRV. Ile98Pro→Ser and Pro100Asn increase 90s loop flexibility, Gln99Val contributes hydrophobic contacts to DRV and LPV, and Pro100Asn forms compensatory hydrogen bonds. The chimeric PR exhibits a comparable number of hydrogen bonds, electrostatic interactions and hydrophobic contacts with DRV and LPV as in the corresponding HIV PR complexes, consistent with IC{sub 50} values in the nanomolar range.

  10. Effects of lactoferrin on elicitation of the antigen-specific cellular and humoral cutaneous response in mice

    Directory of Open Access Journals (Sweden)

    Michał Zimecki

    2012-01-01

    Full Text Available Immune contact dermatitis is an inflammation of the skin resulting from exposure to allergens in the environment. The aim of this study was to compare the actions of lactoferrin (LF, a natural immunomodulator, on the elicitation phases of the cellular and humoral, cutaneous immune responses to oxazolone and toluene diisocyanate (TDI, respectively. LF was given i.v. in a 10 mg/mouse dose, together with the eliciting doses of the antigens. The ear edema and the number of lymphocytes in the draining lymph nodes were measured. In addition, the production of IL-2 in the cultures of lymph node cells and the content of IL-4 in lymph node cells were determined. LF had a profound inhibitory effect on the eliciting phase of the immune response to oxazolone as measured by the ear edema and lymph node cell number. The suppressive effect of LF on the effector phase of the immune response to TDI was moderate. LF had some stimulatory effect on the ex vivo content of IL-4 in lymphocytes in the immune response to TDI. On the other hand, it significantly inhibited IL-2 in vitro production in the immune response to oxazolone. The data strongly suggest that LF exerted differential actions on the activities of antigen-specific Th1 and Th2 cells involved in respective types of the cutaneous immune responses.

  11. Complement-Opsonized HIV-1 Overcomes Restriction in Dendritic Cells.

    Directory of Open Access Journals (Sweden)

    Wilfried Posch

    2015-06-01

    Full Text Available DCs express intrinsic cellular defense mechanisms to specifically inhibit HIV-1 replication. Thus, DCs are productively infected only at very low levels with HIV-1, and this non-permissiveness of DCs is suggested to go along with viral evasion. We now illustrate that complement-opsonized HIV-1 (HIV-C efficiently bypasses SAMHD1 restriction and productively infects DCs including BDCA-1 DCs. Efficient DC infection by HIV-C was also observed using single-cycle HIV-C, and correlated with a remarkable elevated SAMHD1 T592 phosphorylation but not SAMHD1 degradation. If SAMHD1 phosphorylation was blocked using a CDK2-inhibitor HIV-C-induced DC infection was also significantly abrogated. Additionally, we found a higher maturation and co-stimulatory potential, aberrant type I interferon expression and signaling as well as a stronger induction of cellular immune responses in HIV-C-treated DCs. Collectively, our data highlight a novel protective mechanism mediated by complement opsonization of HIV to effectively promote DC immune functions, which might be in the future exploited to tackle HIV infection.

  12. The breadth and titer of maternal HIV-1-specific heterologous neutralizing antibodies are not associated with a lower rate of mother-to-child transmission of HIV-1.

    Science.gov (United States)

    Chaillon, Antoine; Wack, Thierry; Braibant, Martine; Mandelbrot, Laurent; Blanche, Stéphane; Warszawski, Josiane; Barin, Francis

    2012-10-01

    It has been hypothesized that neutralizing antibodies (NAbs) should have broad specificity to be effective in protection against diverse HIV-1 variants. The mother-to-child transmission model of HIV-1 provides the opportunity to examine whether the breadth of maternal NAbs is associated with protection of infants from infection. Samples were obtained at delivery from 57 transmitting mothers (T) matched with 57 nontransmitting mothers (NT) enrolled in the multicenter French perinatal cohort (ANRS EPF CO1) between 1990 and 1996. Sixty-eight (59.6%) and 46 (40.4%) women were infected by B and non-B viruses, respectively. Neutralization assays were carried out with TZM-bl cells, using a panel of 10 primary isolates of 6 clades (A, B, C, F, CRF01_AE, and CRF02_AG), selected for their moderate or low sensitivity to neutralization. Neutralization breadths were not statistically different between T and NT mothers. However, a few statistically significant differences were observed, with higher frequencies or titers of NAbs toward several individual strains for NT mothers when the clade B-infected or non-clade B-infected mothers were analyzed separately. Our study confirms that the breadth of maternal NAbs is not associated with protection of infants from infection.

  13. The Breadth and Titer of Maternal HIV-1-Specific Heterologous Neutralizing Antibodies Are Not Associated with a Lower Rate of Mother-to-Child Transmission of HIV-1

    Science.gov (United States)

    Chaillon, Antoine; Wack, Thierry; Braibant, Martine; Mandelbrot, Laurent; Blanche, Stéphane; Warszawski, Josiane

    2012-01-01

    It has been hypothesized that neutralizing antibodies (NAbs) should have broad specificity to be effective in protection against diverse HIV-1 variants. The mother-to-child transmission model of HIV-1 provides the opportunity to examine whether the breadth of maternal NAbs is associated with protection of infants from infection. Samples were obtained at delivery from 57 transmitting mothers (T) matched with 57 nontransmitting mothers (NT) enrolled in the multicenter French perinatal cohort (ANRS EPF CO1) between 1990 and 1996. Sixty-eight (59.6%) and 46 (40.4%) women were infected by B and non-B viruses, respectively. Neutralization assays were carried out with TZM-bl cells, using a panel of 10 primary isolates of 6 clades (A, B, C, F, CRF01_AE, and CRF02_AG), selected for their moderate or low sensitivity to neutralization. Neutralization breadths were not statistically different between T and NT mothers. However, a few statistically significant differences were observed, with higher frequencies or titers of NAbs toward several individual strains for NT mothers when the clade B-infected or non-clade B-infected mothers were analyzed separately. Our study confirms that the breadth of maternal NAbs is not associated with protection of infants from infection. PMID:22811522

  14. Mutations of Conserved Residues in the Major Homology Region Arrest Assembling HIV-1 Gag as a Membrane-Targeted Intermediate Containing Genomic RNA and Cellular Proteins.

    Science.gov (United States)

    Tanaka, Motoko; Robinson, Bridget A; Chutiraka, Kasana; Geary, Clair D; Reed, Jonathan C; Lingappa, Jaisri R

    2015-12-09

    The major homology region (MHR) is a highly conserved motif that is found within the Gag protein of all orthoretroviruses and some retrotransposons. While it is widely accepted that the MHR is critical for assembly of HIV-1 and other retroviruses, how the MHR functions and why it is so highly conserved are not understood. Moreover, consensus is lacking on when HIV-1 MHR residues function during assembly. Here, we first addressed previous conflicting reports by confirming that MHR deletion, like conserved MHR residue substitution, leads to a dramatic reduction in particle production in human and nonhuman primate cells expressing HIV-1 proviruses. Next, we used biochemical analyses and immunoelectron microscopy to demonstrate that conserved residues in the MHR are required after assembling Gag has associated with genomic RNA, recruited critical host factors involved in assembly, and targeted to the plasma membrane. The exact point of inhibition at the plasma membrane differed depending on the specific mutation, with one MHR mutant arrested as a membrane-associated intermediate that is stable upon high-salt treatment and other MHR mutants arrested as labile, membrane-associated intermediates. Finally, we observed the same assembly-defective phenotypes when the MHR deletion or conserved MHR residue substitutions were engineered into Gag from a subtype B, lab-adapted provirus or Gag from a subtype C primary isolate that was codon optimized. Together, our data support a model in which MHR residues act just after membrane targeting, with some MHR residues promoting stability and another promoting multimerization of the membrane-targeted assembling Gag oligomer. The retroviral Gag protein exhibits extensive amino acid sequence variation overall; however, one region of Gag, termed the major homology region, is conserved among all retroviruses and even some yeast retrotransposons, although the reason for this conservation remains poorly understood. Highly conserved residues

  15. The intriguing Cyclophilin A-HIV-1 Vpr interaction: prolyl cis/trans isomerisation catalysis and specific binding

    Directory of Open Access Journals (Sweden)

    Henklein Petra

    2010-10-01

    Full Text Available Abstract Background Cyclophilin A (CypA represents a potential target for antiretroviral therapy since inhibition of CypA suppresses human immunodeficiency virus type 1 (HIV-1 replication, although the mechanism through which CypA modulates HIV-1 infectivity still remains unclear. The interaction of HIV-1 viral protein R (Vpr with the human peptidyl prolyl isomerase CypA is known to occur in vitro and in vivo. However, the nature of the interaction of CypA with Pro-35 of N-terminal Vpr has remained undefined. Results Characterization of the interactions of human CypA with N-terminal peptides of HIV-1 Vpr has been achieved using a combination of nuclear magnetic resonace (NMR exchange spectroscopy and surface plasmon resonance spectroscopy (SPR. NMR data at atomic resolution indicate prolyl cis/trans isomerisation of the highly conserved proline residues Pro-5, -10, -14 and -35 of Vpr are catalyzed by human CypA and require only very low concentrations of the isomerase relative to that of the peptide substrates. Of the N-terminal peptides of Vpr only those containing Pro-35 bind to CypA in a biosensor assay. SPR studies of specific N-terminal peptides with decreasing numbers of residues revealed that a seven-residue motif centred at Pro-35 consisting of RHFPRIW, which under membrane-like solution conditions comprises the loop region connecting helix 1 and 2 of Vpr and the two terminal residues of helix 1, is sufficient to maintain strong specific binding. Conclusions Only N-terminal peptides of Vpr containing Pro-35, which appears to be vital for manifold functions of Vpr, bind to CypA in a biosensor assay. This indicates that Pro-35 is essential for a specific CypA-Vpr binding interaction, in contrast to the general prolyl cis/trans isomerisation observed for all proline residues of Vpr, which only involve transient enzyme-substrate interactions. Previously suggested models depicting CypA as a chaperone that plays a role in HIV-1 virulence are

  16. Subunit-specific mutational analysis of residue N348 in HIV-1 reverse transcriptase.

    Science.gov (United States)

    Radzio, Jessica; Sluis-Cremer, Nicolas

    2011-08-22

    N348I in HIV-1 reverse transcriptase (RT) confers resistance to zidovudine (AZT) and nevirapine. Biochemical studies demonstrated that N348I indirectly increases AZT resistance by decreasing the frequency of secondary ribonuclease H (RNase H) cleavages that reduce the RNA/DNA duplex length of the template/primer (T/P) and diminish the efficiency of AZT-monophosphate (MP) excision. By contrast, there is some discrepancy in the literature in regard to the mechanisms associated with nevirapine resistance: one study suggested that it is due to decreased inhibitor binding while others suggest that it may be related to the decreased RNase H cleavage phenotype. From a structural perspective, N348 in both subunits of RT resides distal to the enzyme's active sites, to the T/P binding tract and to the nevirapine-binding pocket. As such, the structural mechanisms associated with the resistance phenotypes are not known. Using a novel modelled structure of RT in complex with an RNA/DNA T/P, we identified a putative interaction between the β14-β15 loop in the p51 subunit of RT and the RNA template. Substitution of the asparagine at codon 348 in the p51 subunit with either isoleucine or leucine abrogated the observed protein-RNA interaction, thus, providing a possible explanation for the decreased RNase H phenotype. By contrast, alanine or glutamine substitutions exerted no effect. To validate this model, we introduced the N348I, N348L, N348A and N348Q mutations into RT and purified enzymes that contained subunit-specific mutations. N348I and N348L significantly decreased the frequency of secondary RNase H cleavages and increased the enzyme's ability to excise AZT-MP. As predicted by the modelling, this phenotype was due to the mutation in the p51 subunit of RT. By contrast, the N348A and N348Q RTs exhibited RNase H cleavage profiles and AZT-MP excision activities similar to the wild-type enzyme. All N348 mutant RTs exhibited decreased nevirapine susceptibility, although the N

  17. Subunit-specific mutational analysis of residue N348 in HIV-1 reverse transcriptase

    Directory of Open Access Journals (Sweden)

    Radzio Jessica

    2011-08-01

    Full Text Available Abstract Background N348I in HIV-1 reverse transcriptase (RT confers resistance to zidovudine (AZT and nevirapine. Biochemical studies demonstrated that N348I indirectly increases AZT resistance by decreasing the frequency of secondary ribonuclease H (RNase H cleavages that reduce the RNA/DNA duplex length of the template/primer (T/P and diminish the efficiency of AZT-monophosphate (MP excision. By contrast, there is some discrepancy in the literature in regard to the mechanisms associated with nevirapine resistance: one study suggested that it is due to decreased inhibitor binding while others suggest that it may be related to the decreased RNase H cleavage phenotype. From a structural perspective, N348 in both subunits of RT resides distal to the enzyme's active sites, to the T/P binding tract and to the nevirapine-binding pocket. As such, the structural mechanisms associated with the resistance phenotypes are not known. Results Using a novel modelled structure of RT in complex with an RNA/DNA T/P, we identified a putative interaction between the β14-β15 loop in the p51 subunit of RT and the RNA template. Substitution of the asparagine at codon 348 in the p51 subunit with either isoleucine or leucine abrogated the observed protein-RNA interaction, thus, providing a possible explanation for the decreased RNase H phenotype. By contrast, alanine or glutamine substitutions exerted no effect. To validate this model, we introduced the N348I, N348L, N348A and N348Q mutations into RT and purified enzymes that contained subunit-specific mutations. N348I and N348L significantly decreased the frequency of secondary RNase H cleavages and increased the enzyme's ability to excise AZT-MP. As predicted by the modelling, this phenotype was due to the mutation in the p51 subunit of RT. By contrast, the N348A and N348Q RTs exhibited RNase H cleavage profiles and AZT-MP excision activities similar to the wild-type enzyme. All N348 mutant RTs exhibited decreased

  18. Maturation and Mip-1β Production of Cytomegalovirus-Specific T Cell Responses in Tanzanian Children, Adolescents and Adults: Impact by HIV and Mycobacterium tuberculosis Co-Infections.

    Directory of Open Access Journals (Sweden)

    Damien Portevin

    Full Text Available It is well accepted that aging and HIV infection are associated with quantitative and functional changes of CMV-specific T cell responses. We studied here the expression of Mip-1β and the T cell maturation marker CD27 within CMVpp65-specific CD4(+ and CD8(+ T cells in relation to age, HIV and active Tuberculosis (TB co-infection in a cohort of Tanzanian volunteers (≤ 16 years of age, n = 108 and ≥ 18 years, n = 79. Independent of HIV co-infection, IFNγ(+ CMVpp65-specific CD4(+ T cell frequencies increased with age. In adults, HIV co-infection further increased the frequencies of these cells. A high capacity for Mip-1β production together with a CD27(low phenotype was characteristic for these cells in children and adults. Interestingly, in addition to HIV co-infection active TB disease was linked to further down regulation of CD27 and increased capacity of Mip-1β production in CMVpp65-specific CD4+ T cells. These phenotypic and functional changes of CMVpp65-specific CD4 T cells observed during HIV infection and active TB could be associated with increased CMV reactivation rates.

  19. HCV Specific IL-21 Producing T Cells but Not IL-17A Producing T Cells Are Associated with HCV Viral Control in HIV/HCV Coinfection

    Science.gov (United States)

    MacParland, Sonya A.; Fadel, Saleh M.; Mihajlovic, Vesna; Fawaz, Ali; Kim, Connie; Rahman, A. K. M. Nur-ur; Liu, Jun; Kaul, Rupert; Kovacs, Colin; Grebely, Jason; Dore, Gregory J.; Wong, David K.; Ostrowski, Mario A.

    2016-01-01

    Background Decreased hepatitis C virus (HCV) clearance, faster cirrhosis progression and higher HCV RNA levels are associated with Human Immunodeficiency virus (HIV) coinfection. The CD4+ T helper cytokines interleukin (IL)-21 and IL-17A are associated with virus control and inflammation, respectively, both important in HCV and HIV disease progression. Here, we examined how antigen-specific production of these cytokines during HCV mono and HIV/HCV coinfection was associated with HCV virus control. Methods We measured HCV-specific IL-21 and IL-17A production by transwell cytokine secretion assay in PBMCs from monoinfected and coinfected individuals. Viral control was determined by plasma HCV RNA levels. Results In acutely infected individuals, those able to establish transient/complete HCV viral control tended to have stronger HCV-specific IL-21-production than non-controllers. HCV-specific IL-21 production also correlated with HCV viral decline in acute infection. Significantly stronger HCV-specific IL-21 production was detected in HAART-treated coinfected individuals. HCV-specific IL-17A production was not associated with lower plasma HCV RNA levels in acute or chronic HCV infection and responses were stronger in HIV coinfection. HCV-specific IL-21/ IL-17A responses did not correlate with microbial translocation or fibrosis. Exogenous IL-21 treatment of HCV-specific CD8+ T cells from monoinfected individuals enhanced their function although CD8+ T cells from coinfected individuals were somewhat refractory to the effects of IL-21. Conclusions These data show that HCV-specific IL-21 and IL-17A-producing T cells are induced in HIV/HCV coinfection. In early HIV/HCV coinfection, IL-21 may contribute to viral control, and may represent a novel tool to enhance acute HCV clearance in HIV/HCV coinfected individuals. PMID:27124305

  20. Specifically modified Env immunogens activate B-cell precursors of broadly neutralizing HIV-1 antibodies in transgenic mice.

    Science.gov (United States)

    McGuire, Andrew T; Gray, Matthew D; Dosenovic, Pia; Gitlin, Alexander D; Freund, Natalia T; Petersen, John; Correnti, Colin; Johnsen, William; Kegel, Robert; Stuart, Andrew B; Glenn, Jolene; Seaman, Michael S; Schief, William R; Strong, Roland K; Nussenzweig, Michel C; Stamatatos, Leonidas

    2016-02-24

    VRC01-class broadly neutralizing HIV-1 antibodies protect animals from experimental infection and could contribute to an effective vaccine response. Their predicted germline forms (gl) bind Env inefficiently, which may explain why they are not elicited by HIV-1 Env-immunization. Here we show that an optimized Env immunogen can engage multiple glVRC01-class antibodies. Furthermore, this immunogen activates naive B cells expressing the human germline heavy chain of 3BNC60, paired with endogenous mouse light chains in vivo. To address whether it activates B cells expressing the fully humanized gl3BNC60 B-cell receptor (BCR), we immunized mice carrying both the heavy and light chains of gl3BNC60. B cells expressing this BCR display an autoreactive phenotype and fail to respond efficiently to soluble forms of the optimized immunogen, unless it is highly multimerized. Thus, specifically designed Env immunogens can activate naive B cells expressing human BCRs corresponding to precursors of broadly neutralizing HIV-1 antibodies even when the B cells display an autoreactive phenotype.

  1. HIV-1 clade C escapes broadly neutralizing autologous antibodies with N332 glycan specificity by distinct mechanisms.

    Science.gov (United States)

    Deshpande, Suprit; Patil, Shilpa; Kumar, Rajesh; Hermanus, Tandile; Murugavel, Kailapuri G; Srikrishnan, Aylur K; Solomon, Suniti; Morris, Lynn; Bhattacharya, Jayanta

    2016-08-30

    The glycan supersite centered on N332 in the V3 base of the HIV-1 envelope (Env) is a target for broadly neutralizing antibodies (bnAbs) such as PGT121 and PGT128. In this study, we examined the basis of resistance of HIV-1 clade C Envs obtained from broadly cross neutralizing (BCN) plasma of an Indian donor with N332 specificity. Pseudotyped viruses expressing autologous envs were found to be resistant to autologous BCN plasma as well as to PGT121 and PGT128 mAbs despite the majority of Envs containing an intact N332 residue. While resistance of one of the Envs to neutralization by autologous plasma antibodies with shorter V1 loop length was found to be correlated with a N332S mutation, resistance to neutralization of rest of the Envs was found to be associated with longer V1 loop length and acquisition of protective N-glycans. In summary, we show evidence of escape of circulating HIV-1 clade C in an individual from autologous BCN antibodies by three distinct mechanisms.

  2. Position-specific automated processing of V3 env ultra-deep pyrosequencing data for predicting HIV-1 tropism.

    Science.gov (United States)

    Jeanne, Nicolas; Saliou, Adrien; Carcenac, Romain; Lefebvre, Caroline; Dubois, Martine; Cazabat, Michelle; Nicot, Florence; Loiseau, Claire; Raymond, Stéphanie; Izopet, Jacques; Delobel, Pierre

    2015-11-20

    HIV-1 coreceptor usage must be accurately determined before starting CCR5 antagonist-based treatment as the presence of undetected minor CXCR4-using variants can cause subsequent virological failure. Ultra-deep pyrosequencing of HIV-1 V3 env allows to detect low levels of CXCR4-using variants that current genotypic approaches miss. However, the computation of the mass of sequence data and the need to identify true minor variants while excluding artifactual sequences generated during amplification and ultra-deep pyrosequencing is rate-limiting. Arbitrary fixed cut-offs below which minor variants are discarded are currently used but the errors generated during ultra-deep pyrosequencing are sequence-dependant rather than random. We have developed an automated processing of HIV-1 V3 env ultra-deep pyrosequencing data that uses biological filters to discard artifactual or non-functional V3 sequences followed by statistical filters to determine position-specific sensitivity thresholds, rather than arbitrary fixed cut-offs. It allows to retain authentic sequences with point mutations at V3 positions of interest and discard artifactual ones with accurate sensitivity thresholds.

  3. The cellular prion protein interacts with the tissue non-specific alkaline phosphatase in membrane microdomains of bioaminergic neuronal cells.

    Directory of Open Access Journals (Sweden)

    Myriam Ermonval

    Full Text Available BACKGROUND: The cellular prion protein, PrP(C, is GPI anchored and abundant in lipid rafts. The absolute requirement of PrP(C in neurodegeneration associated to prion diseases is well established. However, the function of this ubiquitous protein is still puzzling. Our previous work using the 1C11 neuronal model, provided evidence that PrP(C acts as a cell surface receptor. Besides a ubiquitous signaling function of PrP(C, we have described a neuronal specificity pointing to a role of PrP(C in neuronal homeostasis. 1C11 cells, upon appropriate induction, engage into neuronal differentiation programs, giving rise either to serotonergic (1C11(5-HT or noradrenergic (1C11(NE derivatives. METHODOLOGY/PRINCIPAL FINDINGS: The neuronal specificity of PrP(C signaling prompted us to search for PrP(C partners in 1C11-derived bioaminergic neuronal cells. We show here by immunoprecipitation an association of PrP(C with an 80 kDa protein identified by mass spectrometry as the tissue non-specific alkaline phosphatase (TNAP. This interaction occurs in lipid rafts and is restricted to 1C11-derived neuronal progenies. Our data indicate that TNAP is implemented during the differentiation programs of 1C11(5-HT and 1C11(NE cells and is active at their cell surface. Noteworthy, TNAP may contribute to the regulation of serotonin or catecholamine synthesis in 1C11(5-HT and 1C11(NE bioaminergic cells by controlling pyridoxal phosphate levels. Finally, TNAP activity is shown to modulate the phosphorylation status of laminin and thereby its interaction with PrP. CONCLUSION/SIGNIFICANCE: The identification of a novel PrP(C partner in lipid rafts of neuronal cells favors the idea of a role of PrP in multiple functions. Because PrP(C and laminin functionally interact to support neuronal differentiation and memory consolidation, our findings introduce TNAP as a functional protagonist in the PrP(C-laminin interplay. The partnership between TNAP and PrP(C in neuronal cells may

  4. 接受48周高效抗逆转录病毒治疗的艾滋病患者细胞内HIV DNA定量检测及其意义%Cellular HIV DNA quantitative testing and its significance in Chinese AIDS patients during 48 weeks' highly-active antiretroviral treatment

    Institute of Scientific and Technical Information of China (English)

    郑煜煌; 姚运海; 林一鹤; 谌资; 周华英; Diallo Mamadou Alius; 陈霞; 何艳; 贺波; 贺梅; 王红艳; 肖水灵; 罗艳

    2012-01-01

    chronic HIV-1 infected adults naively received HAART.The peripheral blood T lymphocyte subsets counts were determined by flux cytometry at week 0,24 and 48.Magnetic activated cell sorting was used to extract cellular DNA from monocytes and T lymphocytes purified from peripheral blood mononuclear cells.Real-time fluorescent quantitative PCR was used to detect the serum HIV RNA and HIV DNA of monocytes and T lymphocytes.SPSS 18.0 software was used to analyze the collected data.Results At week 0,24,and 48 after initiation of HAART,HIV RNA levels of peripheral blood were (4.12 ± 1.41 ),≤1.69,and ≤1.69 lg copies/ml,respectively ; CD4+ T cells were ( 196 ± 101 ),(321.90 ± 112) and ( 392 ± 127 ) cells/μl,respectively ; HIV DNA level in T lymphocytes were ( 4.03 ± 0.53 ),( 2.74 ± 1.16 ) and ( 2.45 ± 0.41 )lg copies/106 cells respectively; while in monocytes,HIV DNA levels were (2.51 ±0.68),(2.16 ±0.34) and (2.03 ± 0.25 )lg copies/106 cells.Statistical analysis revealed that HIV RNA level was negatively correlated with the CD4+ T cell count through the whole trail,while positively correlated with the HIV DNA level in blood T lymphocytes and monocytes.HIV DNA level in T lymphocytes decreased more slowly than HIV DNA in monocytes. Moreover,peripheral blood CD4+ T cell count was negatively associated with the HIV DNA capacity from T lymphocytes.Conclusions Both T lymphocyte and monocyte may serve as viral reservoirs,and T lymphocyte might play a more important role as HIV reservoirs. The blood HIV RNA is correlated positively with the cellular HIV DNA,whereas,CD4+ T cell count is correlated negatively with HIV DNA from lymphocytes,which suggests that HIV DNA levels in T lymphocyte might be one of indicators of AIDS progress during HAART.

  5. Early and prolonged antiretroviral therapy is associated with an HIV-1-specific T-cell profile comparable to that of long-term non-progressors.

    Directory of Open Access Journals (Sweden)

    Cristina Cellerai

    Full Text Available BACKGROUND: Intervention with antiretroviral treatment (ART and control of viral replication at the time of HIV-1 seroconversion may curtail cumulative immunological damage. We have therefore hypothesized that ART maintenance over a very prolonged period in HIV-1 seroconverters could induce an immuno-virological status similar to that of HIV-1 long-term non-progressors (LTNPs. METHODOLOGY/PRINCIPAL FINDINGS: We have investigated a cohort of 20 HIV-1 seroconverters on long-term ART (LTTS and compared it to one of 15 LTNPs. Residual viral replication and reservoirs in peripheral blood, as measured by cell-associated HIV-1 RNA and DNA, respectively, were demonstrated to be similarly low in both cohorts. These two virologically matched cohorts were then comprehensively analysed by polychromatic flow cytometry for HIV-1-specific CD4(+ and CD8(+ T-cell functional profile in terms of cytokine production and cytotoxic capacity using IFN-γ, IL-2, TNF-α production and perforin expression, respectively. Comparable levels of highly polyfunctional HIV-1-specific CD4(+ and CD8(+ T-cells were found in LTTS and LTNPs, with low perforin expression on HIV-1-specific CD8(+ T-cells, consistent with a polyfunctional/non-cytotoxic profile in a context of low viral burden. CONCLUSIONS: Our results indicate that prolonged ART initiated at the time of HIV-1 seroconversion is associated with immuno-virological features which resemble those of LTNPs, strengthening the recent emphasis on the positive impact of early treatment initiation and paving the way for further interventions to promote virological control after treatment interruption.

  6. Sequence-specific fluorometric recognition of HIV-1 ds-DNA with zwitterionic zinc(II)-carboxylate polymers.

    Science.gov (United States)

    Sun, Bin; Zhao, Hai-Qing; Xie, Bao-Ping; Bai, Li-Ping; Jiang, Zhi-Hong; Chen, Jin-Xiang

    2017-11-01

    Four water-stable zwitterionic zinc-carboxylate polymers are prepared by reacting N-carboxymethyl-(3,5-dicarboxy)-pyridinium bromide (H3CmdcpBr) with zinc(II) nitrate in the presence of NaOH, through adjusting the solvents and ancillary ligands. With H2O as the solvent and the absence of an ancillary ligand, a two-dimensional (2D) polymer network [Zn(Cmdcp)(H2O)]n (1) is formed. In a mixed H2O/DMF solvent and with the presence of chelating ligands 2,2'-bipyridine (bipy), 1,10-phenanthroline (phen) and 2-(4-pyridyl)benzimidazole (pbz), a one-dimensional (1D) polymer of {[Zn2(Cmdcp)(bipy)2(H2O)5](NO3)2·3H2O}n (2), a mononuclear ionic species of [Zn(phen)(H2O)4][Cmdcp] (3), and a 2D polymer of {[Zn(Cmdcp)(pbz)][pbz]·7H2O}n (4) are accordingly formed. Compounds 1-4 are characterized by IR, elemental analyses and single crystal X-ray crystallography. Compound 2 strongly adsorbs single-stranded DNA (ss-DNA) probe (denoted as P-DNA) labeled with carboxyfluorescein (FAM) and quenches its fluorescence via a photo-induced electron transfer process. If, however, a double-stranded DNA (ds-DNA) of the human immunodeficiency virus 1 (HIV-1 ds-DNA) is further present, the P-DNA interacts with the major groove in HIV-1 ds-DNA via Hoogsteen hydrogen bonding to form a rigid triplex structure. This results in partial or complete fluorescence recovery depending on the concentration of HIV-1 ds-DNA. The findings are applied in fluorometric sensing of HIV-1 ds-DNA. The calibration plot is linear in the 0-60nM target DNA concentration range, with a 7.4nM detection limit (at a signal-to-noise ratio of 3). The assay is highly specific and not interfered by one base pair mutated for complementary target HIV-1 ds-DNA, complementary ss-DNA, single-base pair mutated for complementary ss-DNA, non-specific ss-DNA sequences, and higher-order dimeric G-quadruplexes. Copyright © 2017 Elsevier Inc. All rights reserved.

  7. The cellular chaperone hsc70 is specifically recruited to reovirus viral factories independently of its chaperone function.

    Science.gov (United States)

    Kaufer, Susanne; Coffey, Caroline M; Parker, John S L

    2012-01-01

    Mammalian orthoreoviruses replicate and assemble in the cytosol of infected cells. A viral nonstructural protein, μNS, forms large inclusion-like structures called viral factories (VFs) in which assembling viral particles can be identified. Here we examined the localization of the cellular chaperone Hsc70 and found that it colocalizes with VFs in infected cells and also with viral factory-like structures (VFLs) formed by ectopically expressed μNS. Small interfering RNA (siRNA)-mediated knockdown of Hsc70 did not affect the formation or maintenance of VFLs. We further showed that dominant negative mutants of Hsc70 were also recruited to VFLs, indicating that Hsc70 recruitment to VFLs is independent of the chaperone function. In support of this finding, μNS was immunoprecipitated with wild-type Hsc70, with a dominant negative mutant of Hsc70, and with the minimal substrate-binding site of Hsc70 (amino acids 395 to 540). We identified a minimal region of μNS between amino acids 222 and 271 that was sufficient for the interaction with Hsc70. This region of μNS has not been assigned any function previously. However, neither point mutants with alterations in this region nor the complete deletion of this domain abrogated the μNS-Hsc70 interaction, indicating that a second portion of μNS also interacts with Hsc70. Taken together, these findings suggest a specific chaperone function for Hsc70 within viral factories, the sites of reovirus replication and assembly in cells.

  8. Dialysis purification of integrase-DNA complexes provides high-resolution atomic force microscopy images: dimeric recombinant HIV-1 integrase binding and specific looping on DNA.

    Directory of Open Access Journals (Sweden)

    Tatsuaki Tsuruyama

    Full Text Available It remains difficult to obtain high-resolution atomic force microscopy images of HIV-1 integrase bound to DNA in a dimeric or tetrameric fashion. We therefore constructed specific target DNAs to assess HIV-1 integrase binding and purified the complex by dialysis prior to analysis. Our resulting atomic force microscopy analyses indicated precise size of binding human immunodeficiency virus type 1 (HIV-1 recombinant integrase in a tetrameric manner, inducing formation of a loop-like or figure-eight-like secondary structure in the target DNA. Our findings regarding the target DNA secondary structure provide new insights into the intermediate states of retroviral integration.

  9. Dialysis purification of integrase-DNA complexes provides high-resolution atomic force microscopy images: dimeric recombinant HIV-1 integrase binding and specific looping on DNA.

    Science.gov (United States)

    Tsuruyama, Tatsuaki; Nakai, Tonau; Ohmori, Rei; Ozeki, Munetaka; Tamaki, Keiji; Yoshikawa, Kenichi

    2013-01-01

    It remains difficult to obtain high-resolution atomic force microscopy images of HIV-1 integrase bound to DNA in a dimeric or tetrameric fashion. We therefore constructed specific target DNAs to assess HIV-1 integrase binding and purified the complex by dialysis prior to analysis. Our resulting atomic force microscopy analyses indicated precise size of binding human immunodeficiency virus type 1 (HIV-1) recombinant integrase in a tetrameric manner, inducing formation of a loop-like or figure-eight-like secondary structure in the target DNA. Our findings regarding the target DNA secondary structure provide new insights into the intermediate states of retroviral integration.

  10. Insight into the impact of dietary saturated fat on tissue-specific cellular processes underlying obesity-related diseases.

    Science.gov (United States)

    Enos, Reilly T; Velázquez, Kandy T; Murphy, E Angela

    2014-06-01

    This study investigated the influence of three high-fat diets (HFDs), differing in the percentage of total calories from saturated fat (SF) (6%, 12%, 24%) but identical in total fat (40%), for a 16-week period in mice on a variety of tissue-specific cellular processes believed to be at the root of obesity-related diseases. Specifically, we examined ectopic lipid accumulation, oxidative capacity [peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α) mRNA and protein; mtDNA; Cox IV and cytochrome C protein; citrate synthase activity; and gene expression of fission 1, mitofusin (Mfn) 1 and Mfn2], oxidative stress (4-hydroxy-2-nonenal), endoplasmic reticulum (ER) stress (binding immunoglobulin protein, activating transcription factor 6-p50, p-eukaryotic initiation factor 2 alpha and x-box binding protein 1 spliced protein), inflammatory [p-c-Jun N-terminal kinase (JNK), p-nuclear factor kappa-B, p-p38 mitogen-activated protein kinase) and insulin signaling (p-Akt), and inflammation [tumor necrosis factor-alpha, monocyte chemotactic protein-1, interleukin-6, F4/80, toll-like receptor (TLR)2 and TLR4 gene expression] in various tissues, including the adipose tissue, liver, skeletal muscle and heart. In general, adipose and hepatic tissues were the only tissues which displayed evidence of dysfunction. All HFDs down-regulated adipose, cardiac and hepatic PGC-1α mRNA and hepatic citrate synthase activity, and induced adipose tissue oxidative stress, whereas only the 6%-SF and 12%-SF diet produced hepatic steatosis. However, compared to the 6%-SF and 24%-SF diets, consumption of the 12%-SF diet resulted in the greatest degree of dysregulation (hepatic ER and oxidative stress, JNK activation, increased F4/80 gene expression and down-regulation of adipose tissue Akt signaling). These findings suggest that the saturated fatty acid composition of an HFD can greatly influence the processes responsible for obesity-related diseases - nonalcoholic fatty

  11. Assessing the sensitivity and specificity of First Response HIV-1-2 test kit with whole blood and serum samples: a cross-sectional study

    OpenAIRE

    Boadu, Raymond; Darko, George; Nortey, Priscilla; Akweongo, Patricia; Sarfo, Bismark

    2016-01-01

    Background Human immunodeficiency virus (HIV) Rapid diagnostic Test (RDT) kits are the preferred assays for HIV testing in many countries. Prevention of Mother-to-Child Transmission, Know Your Status Campaigns, Blood-Safety, Voluntary Counseling and Testing are major strategies adapted to control transmission of the virus and the pivot of these interventions is either screening or diagnosing individuals through testing. There are reports of inconsistent sensitivity and specificity with whole ...

  12. A parameter for IL-10 and TGF-ß mediated regulation of HIV-1 specific T cell activation provides novel information and relates to progression markers.

    Directory of Open Access Journals (Sweden)

    Andreas Lind

    Full Text Available HIV replication is only partially controlled by HIV-specific activated effector T cells in chronic HIV infection and strategies are warranted to improve their efficacy. Chronic T cell activation is generally accompanied by regulation of antigen-specific T cell responses which may impair an effective control of chronic infections. The impact of HIV-induced T cell regulation on individual patients' disease progression is largely unknown, since classical T cell activation assays reflect net activation with regulation as unknown contributing factor. We here explore a quantitative parameter for antigen-induced cytokine-mediated regulation (R(AC of HIV-specific effector T cell activation by functional antibody-blockade of IL-10 and transforming growth factor-β. HIV Env- and Gag-specific T cell activation and R(AC were estimated in peripheral blood mononuclear cells from 30 treatment-naïve asymptomatic HIV-infected progressors (CD4 count 472/µl, HIV RNA 37500 copies/ml stimulated with overlapping peptide panels for 6 days. R(AC was estimated from differences in T cell activation between normal and blocked cultures, and related to annual CD4 loss, immune activation (CD38 and microbial translocation (plasma lipopolysaccharides. R(AC was heterogeneously distributed between individual patients and the two HIV antigens. Notably, RAC did not correlate to corresponding classical activation. Env R(AC correlated with CD38 and CD4 loss rates (r> = 0.37, p = <0.046 whereas classical Gag activation tended to correlate with HIV RNA (r = -0.35, p = 0.06. 14 patients (47% with low R(AC's to both Env and Gag had higher CD8 counts (p = 0.014 and trends towards lower annual CD4 loss (p = 0.056 and later start with antiretroviral treatment (p = 0.07 than the others. In contrast, patients with high RAC to both Env and Gag (n = 8 had higher annual CD4 loss (p = 0.034 and lower CD8 counts (p = 0.014. R(AC to Env and Gag was not

  13. A parameter for IL-10 and TGF-ß mediated regulation of HIV-1 specific T cell activation provides novel information and relates to progression markers.

    Science.gov (United States)

    Lind, Andreas; Brekke, Kristin; Pettersen, Frank Olav; Mollnes, Tom Eirik; Trøseid, Marius; Kvale, Dag

    2014-01-01

    HIV replication is only partially controlled by HIV-specific activated effector T cells in chronic HIV infection and strategies are warranted to improve their efficacy. Chronic T cell activation is generally accompanied by regulation of antigen-specific T cell responses which may impair an effective control of chronic infections. The impact of HIV-induced T cell regulation on individual patients' disease progression is largely unknown, since classical T cell activation assays reflect net activation with regulation as unknown contributing factor. We here explore a quantitative parameter for antigen-induced cytokine-mediated regulation (R(AC) of HIV-specific effector T cell activation by functional antibody-blockade of IL-10 and transforming growth factor-β. HIV Env- and Gag-specific T cell activation and R(AC) were estimated in peripheral blood mononuclear cells from 30 treatment-naïve asymptomatic HIV-infected progressors (CD4 count 472/µl, HIV RNA 37500 copies/ml) stimulated with overlapping peptide panels for 6 days. R(AC) was estimated from differences in T cell activation between normal and blocked cultures, and related to annual CD4 loss, immune activation (CD38) and microbial translocation (plasma lipopolysaccharides). R(AC) was heterogeneously distributed between individual patients and the two HIV antigens. Notably, RAC did not correlate to corresponding classical activation. Env R(AC) correlated with CD38 and CD4 loss rates (r> = 0.37, p = <0.046) whereas classical Gag activation tended to correlate with HIV RNA (r = -0.35, p = 0.06). 14 patients (47%) with low R(AC)'s to both Env and Gag had higher CD8 counts (p = 0.014) and trends towards lower annual CD4 loss (p = 0.056) and later start with antiretroviral treatment (p = 0.07) than the others. In contrast, patients with high RAC to both Env and Gag (n = 8) had higher annual CD4 loss (p = 0.034) and lower CD8 counts (p = 0.014). R(AC) to Env and Gag was not

  14. Naturally-acquired influenza-specific CD4+ T-cell proliferative responses are impaired in HIV-infected African adults.

    Directory of Open Access Journals (Sweden)

    Kondwani C Jambo

    Full Text Available BACKGROUND: Seasonal influenza has been associated with greater morbidity and mortality in AIDS patients. Highly-active antiretroviral therapy (HAART has led to some reduction in influenza-related complications but the nature of naturally-acquired T-cell immunity to influenza virus in an African setting, and how this changes with immune reconstitution following HAART is unknown. We measured influenza-specific CD4(+ T-cell immunity in unimmunized HIV-infected Malawian adults and then investigated immune reconstitution following HAART. METHODS: Peripheral blood mononuclear cells were isolated from HIV-infected and HIV-uninfected Malawian adults. CFSE proliferation and CD154 expression flow cytometry-based assays were used to measure influenza-specific CD4(+ T-cell immunity. RESULTS: We found lower naturally-acquired proliferative influenza-specific CD4(+ T-cell responses in AIDS patients that was also present in asymptomatic HIV-infected adults with relatively high CD4 counts (>350 cells/µl. Influenza-specific CD4(+ T-cell immune reconstitution in HIV-infected patients on HAART for 12 months was poor despite a marked reduction in viral load and an increase in CD4 count. This poor immune reconstitution was characterised by a low influenza-specific proliferative CD4(+ T-cell response and reduced proportions of CD154-expressing influenza-specific CD4(+ T-cells in peripheral blood. CONCLUSION: Our data suggest that asymptomatic HIV-infected adults may also be at risk of influenza-related complications and that HAART alone may not circumvent this risk in AIDS patients. This study highlights the need to identify possible interventions early in HIV infection to reduce the risk of influenza and to intensify influenza surveillance in these susceptible African populations.

  15. [Evaluation of infection by Helicobacter pylori in HIV positive patients trough enzyme immunoassay and specific amplification of DNA].

    Science.gov (United States)

    Gutiérrez, Sandra; Chacón-Petrola, María; Flores, María; Pinto, Angela; Pacheco, Mariela

    2005-03-01

    The objective of this work was to assess the effectiveness of detection of specific antibodies anti-Helicobacter pylori (H. pylori) by ELISA and amplification of specific DNA by polimerase chain reaction (PCR) as diagnostic methods of infection of H. pylori in HIV positive patients. Twenty two patients with HIV infection were studied, with ages between 26 to 35 years, 17 masculine, 55% with gastrointestinal symptoms, controlled in the Unit of Immunology, CHET. Inclusion approaches: older than 18 years, with confirmed diagnosis of HIV infection (ELISA and WB), lymphocyte subpopulation and good general conditions. Consent in writing was obtained. Exclusion approaches: previous diagnosis of H. pylori infection or treatment with antibiotics in the three previous months to their inclusion. The quantification of IgG anti H. pylori was carried out by Enzyme Immunoassay methods (ELISA). Biopsy of gastric mucosa was obtained by superior endoscopic study. The amplification of DNA for H. pylori was performed by PCR (Wizard SV Genomik and PCR Ready-Promega). In the statistical analysis was used the test of Fisher, with a level of significance of 5% (0.05). In 15 patients of the total group, antibodies anti H. pylori were confirmed, without statistical association with the presence or not of digestives symptoms, neither with the number of lymphocytes CD4 + in peripheral blood. Also 15 patients were positives by PCR for H. pylori DNA, 73.3% of them presented levels of CD4+ above 200 cells. There was not statistical association between the positivity of this method and levels of lymphocytes CD4+. In 12 of the 15 patients with positive results by PCR, antibodies anti H. pylori were evidenced, and among the 7 patients with negative serology to H. pylori, PCR was positive in three of them. In conclusion, serology is an effective method for the diagnose of H. pylori infection in VIH+ patients, but its negativity doesn't discard the infection for this bacillus.

  16. HIV-1 differentially modulates autophagy in neurons and astrocytes.

    Science.gov (United States)

    Mehla, Rajeev; Chauhan, Ashok

    2015-08-15

    Autophagy, a lysosomal degradative pathway that maintains cellular homeostasis, has emerged as an innate immune defense against pathogens. The role of autophagy in the deregulated HIV-infected central nervous system (CNS) is unclear. We have found that HIV-1-induced neuro-glial (neurons and astrocytes) damage involves modulation of the autophagy pathway. Neuro-glial stress induced by HIV-1 led to biochemical and morphological dysfunctions. X4 HIV-1 produced neuro-glial toxicity coupled with suppression of autophagy, while R5 HIV-1-induced toxicity was restricted to neurons. Rapamycin, a specific mTOR inhibitor (autophagy inducer) relieved the blockage of the autophagy pathway caused by HIV-1 and resulted in neuro-glial protection. Further understanding of the regulation of autophagy by cytokines and chemokines or other signaling events may lead to recognition of therapeutic targets for neurodegenerative diseases.

  17. Nanochemistry-based immunotherapy for HIV-1.

    Science.gov (United States)

    Lori, F; Calarota, S A; Lisziewicz, J

    2007-01-01

    Highly active antiretroviral treatment (HAART), i.e. the combination of three or more drugs against human immunodeficiency virus type 1 (HIV-1), has greatly improved the clinical outcome of HIV-1-infected individuals. However, HAART is unable to reconstitute HIV-specific immunity and eradicate the virus. Several observations in primate models and in humans support the notion that cell-mediated immunity can control viral replication and slow disease progression. Thus, besides drugs, an immunotherapy that induces long-lasting HIV-specific T-cell responses could play a role in the treatment of HIV/AIDS. To induce such immune responses, DermaVir Patch has been developed. DermaVir consists of an HIV-1 antigen-encoding plasmid DNA that is chemically formulated in a nanoparticle. DermaVir is administered under a patch after a skin preparation that supports the delivery of the nanoparticle to Langerhans cells (LC). Epidermal LC trap and transport the nanomedicine to draining lymph nodes. While in transit, LC mature into dendritic cells (DC), which can efficiently present the DNA-encoded antigens to naïve T-cells for the induction of cellular immunity. Pre-clinical studies and Phase I clinical testing of DermaVir in HIV-1-infected individuals have demonstrated the safety and tolerability of DermaVir Patch. To further modulate cellular immunity, molecular adjuvants might be added into the nanoparticle. DermaVir Patch represents a new nanomedicine platform for immunotherapy of HIV/AIDS. In this review, the antiviral activity of DermaVir-induced cellular immunity is discussed. Furthermore, the action of some cytokines currently being tested as adjuvants are highlighted and the adjuvant effect of cytokine plasmid DNA included in the DermaVir nanoparticle is reviewed.

  18. Iron-Restricted Diet Affects Brain Ferritin Levels, Dopamine Metabolism and Cellular Prion Protein in a Region-Specific Manner

    Directory of Open Access Journals (Sweden)

    Jessica M. V. Pino

    2017-05-01

    Full Text Available Iron is an essential micronutrient for several physiological functions, including the regulation of dopaminergic neurotransmission. On the other hand, both iron, and dopamine can affect the folding and aggregation of proteins related with neurodegenerative diseases, such as cellular prion protein (PrPC and α-synuclein, suggesting that deregulation of iron homeostasis and the consequential disturbance of dopamine metabolism can be a risk factor for conformational diseases. These proteins, in turn, are known to participate in the regulation of iron and dopamine metabolism. In this study, we evaluated the effects of dietary iron restriction on brain ferritin levels, dopamine metabolism, and the expression levels of PrPC and α-synuclein. To achieve this goal, C57BL/6 mice were fed with iron restricted diet (IR or with normal diet (CTL for 1 month. IR reduced iron and ferritin levels in liver. Ferritin reduction was also observed in the hippocampus. However, in the striatum of IR group, ferritin level was increased, suggesting that under iron-deficient condition, each brain area might acquire distinct capacity to store iron. Increased lipid peroxidation was observed only in hippocampus of IR group, where ferritin level was reduced. IR also generated discrete results regarding dopamine metabolism of distinct brain regions: in striatum, the level of dopamine metabolites (DOPAC and HVA was reduced; in prefrontal cortex, only HVA was increased along with the enhanced MAO-A activity; in hippocampus, no alterations were observed. PrPC levels were increased only in the striatum of IR group, where ferritin level was also increased. PrPC is known to play roles in iron uptake. Thus, the increase of PrPC in striatum of IR group might be related to the increased ferritin level. α-synuclein was not altered in any regions. Abnormal accumulation of ferritin, increased MAO-A activity or lipid peroxidation are molecular features observed in several neurological

  19. Site-specific differences in T cell frequencies and phenotypes in the blood and gut of HIV-uninfected and ART-treated HIV+ adults.

    Science.gov (United States)

    Yukl, Steven A; Shergill, Amandeep K; Girling, Valerie; Li, Qingsheng; Killian, Maudi; Epling, Lorrie; Li, Peilin; Kaiser, Philipp; Haase, Ashley; Havlir, Diane V; McQuaid, Kenneth; Sinclair, Elizabeth; Wong, Joseph K

    2015-01-01

    Gastrointestinal T lymphocytes are critical for mucosal immunity and HIV pathogenesis, yet little is known about normal T cell numbers and phenotypes in different regions of the gut, or the degree to which ART can restore levels to those of HIV-uninfected individuals. To investigate these questions, we measured T cell frequencies and markers of memory, activation, anergy, and homing in the blood, ileum, and rectum of HIV- and ART-suppressed HIV+ adults. In HIV- individuals, T cell frequencies and phenotypes differed significantly between sites. Compared to HIV- adults, HIV+ adults had lower absolute CD4+T cell counts in the ileal lamina propria and lower relative CD4+T cell counts in the blood and ileum. In the gut, HIV+ adults had a higher proportion of CD38+ CD4+T cells, a lower proportion of terminally-differentiated effector cells, and, in the rectum, a higher proportion of CTLA-4+ CD4+T cells. In HIV+ individuals, relative CD4+T cell numbers in the ileum correlated with the proportion of CTLA-4+ CD4+T cells, whereas in the rectum, they tended to correlate with the proportion of circulating CD4+T cells expressing α4β7 or CCR6. Mechanisms of T cell reconstitution may differ throughout the gut, with homing contributing more in the rectum while ileal reconstitution is associated with mucosal CD4+T cell anergy.

  20. Site-specific differences in T cell frequencies and phenotypes in the blood and gut of HIV-uninfected and ART-treated HIV+ adults.

    Directory of Open Access Journals (Sweden)

    Steven A Yukl

    Full Text Available Gastrointestinal T lymphocytes are critical for mucosal immunity and HIV pathogenesis, yet little is known about normal T cell numbers and phenotypes in different regions of the gut, or the degree to which ART can restore levels to those of HIV-uninfected individuals. To investigate these questions, we measured T cell frequencies and markers of memory, activation, anergy, and homing in the blood, ileum, and rectum of HIV- and ART-suppressed HIV+ adults. In HIV- individuals, T cell frequencies and phenotypes differed significantly between sites. Compared to HIV- adults, HIV+ adults had lower absolute CD4+T cell counts in the ileal lamina propria and lower relative CD4+T cell counts in the blood and ileum. In the gut, HIV+ adults had a higher proportion of CD38+ CD4+T cells, a lower proportion of terminally-differentiated effector cells, and, in the rectum, a higher proportion of CTLA-4+ CD4+T cells. In HIV+ individuals, relative CD4+T cell numbers in the ileum correlated with the proportion of CTLA-4+ CD4+T cells, whereas in the rectum, they tended to correlate with the proportion of circulating CD4+T cells expressing α4β7 or CCR6. Mechanisms of T cell reconstitution may differ throughout the gut, with homing contributing more in the rectum while ileal reconstitution is associated with mucosal CD4+T cell anergy.

  1. Indirect detection of an epitope-specific response to HIV-1 gp120 immunization in human subjects.

    Directory of Open Access Journals (Sweden)

    Evgeny Shmelkov

    Full Text Available A specific response of human serum neutralizing antibodies (nAb to a conformational epitope as a result of vaccination of human subjects with the surface envelope glycoprotein (gp120 of HIV-1 has not previously been documented. Here, we used computational analysis to assess the epitope-specific responses of human subjects, which were immunized with recombinant gp120 immunogens in the VAX003 and VAX004 clinical trials. Our computational methodology--a variation of sieve analysis--compares the occurrence of specific nAb targeted conformational 3D epitopes on viruses from infected individuals who received vaccination to the occurrence of matched epitopes in the viruses infecting placebo subjects. We specifically studied seven crystallographically defined nAb targeted conformational epitopes in the V3 loop, an immunogenic region of gp120. Of the six epitopes present in the immunogens and targeted by known monoclonal neutralizing antibodies, only the one targeted by the anti-V3 nAb 2219 exhibited a significant reduction in occurrence in vaccinated subjects compared to the placebo group. This difference occurred only in the VAX003 Thailand cohort. No difference was seen between vaccinated and placebo groups for the occurrence of an epitope that was not present in the immunogen. Thus, it can be theorized that a specific 2219-like human neutralizing antibody immune response to AIDSVAX immunization occurred in the VAX003 cohort, and that this response protected subjects from a narrow subset of HIV-1 viruses circulating in Thailand in the 1990s and bearing the conformational epitope targeted by the neutralizing antibody 2219.

  2. Induction of cross clade reactive specific antibodies in mice by conjugates of HGP-30 (peptide analog of HIV-1(SF2) p17) and peptide segments of human beta-2-microglobulin or MHC II beta chain.

    Science.gov (United States)

    Zimmerman, D H; Lloyd, J P; Heisey, D; Winship, M D; Siwek, M; Talor, E; Sarin, P S

    2001-09-14

    HGP-30, a 30 amino acid synthetic peptide homologous to a conserved region of HIV-1(SF2) p17 (aa86-115), has previously been shown to elicit both cellular and humoral immune responses when conjugated to KLH and adsorbed to alum. However, the free HGP-30 peptide is not immunogenic in animals. In order to improve the immunogenicity of HGP-30, peptide conjugates consisting of a modified HGP-30 sequence (m-HGP-30/aa82-111) and a peptide segment, residues 38-50, of the MHC I accessory molecule, human beta-2-microglobulin (beta-2-M), referred to as Peptide J, or a peptide from the MHC II beta chain (peptide G) were evaluated in mice. The effects of carriers and adjuvants on serum antibody titers, specificities to various HIV-1 clade peptides similar to HGP-30 and isotype patterns were examined. Peptides J or especially G conjugated to modified-HGP-30 (LEAPS 102 and LEAPS 101, respectively) generated comparable or better immune responses to modified HGP-30 than KLH conjugates as judged by the induction of: (1) similar antibody titers; (2) broader HIV clade antigen binding; and (3) antibody isotype response patterns indicative of a TH1 pathway (i.e. increased amounts of IgG2a and IgG2b antibodies). The ISA 51 and MPL(R)-SE adjuvants induced higher antibody responses than alum, with the ISA 51 being more potent. Immune responses to LEAPS 102, as compared to LEAPS 101, were weaker and slower to develop as determined by antibody titers and cross clade reactivity of the antibodies induced. Compared to KLH conjugates which induced significant anti-KLH antibody titers, minimal antibody responses were observed to peptide G, the more immunogenic conjugate, and peptide J. These results suggest that modified HGP-30 L.E.A.P.S. constructs may be useful as HIV vaccine candidates for preferential induction of TH1 directed cell mediated immune responses.

  3. A genome-wide screen in yeast identifies specific oxidative stress genes required for the maintenance of sub-cellular redox homeostasis.

    Directory of Open Access Journals (Sweden)

    Anita Ayer

    Full Text Available Maintenance of an optimal redox environment is critical for appropriate functioning of cellular processes and cell survival. Despite the importance of maintaining redox homeostasis, it is not clear how the optimal redox potential is sensed and set, and the processes that impact redox on a cellular/organellar level are poorly understood. The genetic bases of cellular redox homeostasis were investigated using a green fluorescent protein (GFP based redox probe, roGFP2 and a pH sensitive GFP-based probe, pHluorin. The use of roGFP2, in conjunction with pHluorin, enabled determination of pH-adjusted sub-cellular redox potential in a non-invasive and real-time manner. A genome-wide screen using both the non-essential and essential gene collections was carried out in Saccharomyces cerevisiae using cytosolic-roGFP2 to identify factors essential for maintenance of cytosolic redox state under steady-state conditions. 102 genes of diverse function were identified that are required for maintenance of cytosolic redox state. Mutations in these genes led to shifts in the half-cell glutathione redox potential by 75-10 mV. Interestingly, some specific oxidative stress-response processes were identified as over-represented in the data set. Further investigation of the role of oxidative stress-responsive systems in sub-cellular redox homeostasis was conducted using roGFP2 constructs targeted to the mitochondrial matrix and peroxisome and E(GSH was measured in cells in exponential and stationary phase. Analyses allowed for the identification of key redox systems on a sub-cellular level and the identification of novel genes involved in the regulation of cellular redox homeostasis.

  4. Cellular penetration and nuclear importation properties of {sup 111}In-labeled and {sup 123}I-labeled HIV-1 tat peptide immunoconjugates in BT-474 human breast cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Cornelissen, Bart [Division of Nuclear Medicine, University Health Network, Toronto, ON, M5S 3M2 (Canada); Department of Pharmaceutical Sciences, University of Toronto, Toronto, ON, M5S 3M2 (Canada); Hu, Meiduo [Division of Nuclear Medicine, University Health Network, Toronto, ON, M5S 3M2 (Canada); Department of Pharmaceutical Sciences, University of Toronto, Toronto, ON, M5S 3M2 (Canada); McLarty, Kristin [Division of Nuclear Medicine, University Health Network, Toronto, ON, M5S 3M2 (Canada); Department of Pharmaceutical Sciences, University of Toronto, Toronto, ON, M5S 3M2 (Canada); Costantini, Dan [Division of Nuclear Medicine, University Health Network, Toronto, ON, M5S 3M2 (Canada); Department of Pharmaceutical Sciences, University of Toronto, Toronto, ON, M5S 3M2 (Canada); Reilly, Raymond M. [Division of Nuclear Medicine, University Health Network, Toronto, ON, M5S 3M2 (Canada) and Department of Medical Imaging, University of Toronto, Toronto, ON, M5S 3M2 (Canada) and Department of Pharmaceutical Sciences, University of Toronto, Toronto, ON, M5S 3M2 (Canada) and Toronto General Research Institute, University Health Network, Toronto, ON, M5S 3M2 (Canada)]. E-mail: raymond.reilly@utoronto.ca

    2007-01-15

    Introduction: Our objective was to compare the cell penetration and nuclear importation properties of {sup 111}In-labeled and {sup 123}I-labeled immunoconjugates (ICs) composed of 16-mer peptides (GRKKRRQRRRPPQGYG) derived from HIV-1 transactivator of transcription (tat) protein and anti-mouse IgG (mIgG) in BT-474 breast cancer (BC) cells. Methods: [{sup 111}In]tat ICs were constructed by site-specific conjugation of tat peptides to NaIO{sub 4} {sup -}-oxidized carbohydrates in the Fc domain of diethylenetriaminepentaacetic-acid-modified anti-mIgG antibodies. Immunoreactivity against mIgG was assessed in a competition assay. The kinetics of the accumulation of [{sup 111}In]anti-mIgG-tat IC and [{sup 123}I]anti-mIgG-tat ICs in BT-474 cells and the elimination of radioactivity from cells, cytoplasm or nuclei were determined. The effects of excess tat peptides or NH{sub 4}Cl (an inhibitor of endosomal acidification) on cellular uptake and nuclear importation of [{sup 111}In]anti-mIgG-tat were measured. Results: [{sup 111}In]anti-mIgG-tat was >97% radiochemically pure and exhibited preserved immunoreactivity with mIgG epitopes. [{sup 123}I]Anti-mIgG-tat penetrated BT-474 cells more rapidly than [{sup 111}In]anti-mIgG-tat ICs and achieved a 1.5-fold to a 2-fold higher uptake in cells and nuclei. Cell penetration and nuclear uptake of [{sup 111}In]anti-mIgG-tat were inhibited by excess tat peptides and NH{sub 4}Cl. Elimination of radioactivity from BT-474 cells and nuclei was more rapid and complete for {sup 123}I-labeled than for {sup 111}In-labeled anti-mIgG-tat ICs. Conclusion: Tat peptides derived from HIV-1 tat protein promoted the penetration and nuclear uptake of radioactivity following the incubation of {sup 111}In-labeled and {sup 123}I-labeled anti-mIgG antibodies with BT-474 human BC cells. {sup 111}In-labeled tat ICs are feasible for inserting radionuclides into cancer cells with potential for targeting intracellular and, particularly, nuclear epitopes for

  5. Cause-Specific Mortality in HIV-Positive Patients Who Survived Ten Years after Starting Antiretroviral Therapy

    Science.gov (United States)

    May, Margaret T.; Vehreschild, Janne; Obel, Niels; Gill, Michael John; Crane, Heidi; Boesecke, Christoph; Samji, Hasina; Grabar, Sophie; Cazanave, Charles; Cavassini, Matthias; Shepherd, Leah; d’Arminio Monforte, Antonella; Smit, Colette; Saag, Michael; Lampe, Fiona; Hernando, Vicky; Montero, Marta; Zangerle, Robert; Justice, Amy C.; Sterling, Timothy; Miro, Jose; Ingle, Suzanne; Sterne, Jonathan A. C.

    2016-01-01

    Objectives To estimate mortality rates and prognostic factors in HIV-positive patients who started combination antiretroviral therapy between 1996–1999 and survived for more than ten years. Methods We used data from 18 European and North American HIV cohort studies contributing to the Antiretroviral Therapy Cohort Collaboration. We followed up patients from ten years after start of combination antiretroviral therapy. We estimated overall and cause-specific mortality rate ratios for age, sex, transmission through injection drug use, AIDS, CD4 count and HIV-1 RNA. Results During 50,593 person years 656/13,011 (5%) patients died. Older age, male sex, injecting drug use transmission, AIDS, and low CD4 count and detectable viral replication ten years after starting combination antiretroviral therapy were associated with higher subsequent mortality. CD4 count at ART start did not predict mortality in models adjusted for patient characteristics ten years after start of antiretroviral therapy. The most frequent causes of death (among 340 classified) were non-AIDS cancer, AIDS, cardiovascular, and liver-related disease. Older age was strongly associated with cardiovascular mortality, injecting drug use transmission with non-AIDS infection and liver-related mortality, and low CD4 and detectable viral replication ten years after starting antiretroviral therapy with AIDS mortality. Five-year mortality risk was <5% in 60% of all patients, and in 30% of those aged over 60 years. Conclusions Viral replication, lower CD4 count, prior AIDS, and transmission via injecting drug use continue to predict higher all-cause and AIDS-related mortality in patients treated with combination antiretroviral therapy for over a decade. Deaths from AIDS and non-AIDS infection are less frequent than deaths from other non-AIDS causes. PMID:27525413

  6. Gender-specific effects of HIV protease inhibitors on body mass in mice

    Directory of Open Access Journals (Sweden)

    Rosewell Amanda N

    2007-05-01

    Full Text Available Abstract Protease inhibitors, as part of highly active anti-retroviral therapy (HAART, have significantly increased the lifespan of human immunodeficiency virus (HIV infected patients. Several deleterious side effects including dyslipidemia and lipodystrophy, however, have been observed with HAART. Women are at a higher risk of developing adipose tissue alterations and these alterations have different characteristics as compared to men. We have previously demonstrated that in mice the HIV protease inhibitor, ritonavir, caused a reduction in weight gain in females, but had no effect on male mice. In the present study, we examined the potential causes of this difference in weight gain. Low-density lipoprotein receptor (LDL-R null mice or wild-type C57BL/6 mice, were administered 15 μg/ml ritonavir or vehicle (0.01% ethanol in the drinking water for 6 weeks. The percent of total body weight gained during the treatment period was measured and confirmed that female LDL-R gained significantly less weight with ritonavir treatment than males. In wild type mice, however, there was no effect of ritonavir treatment in either sex. Despite the weight loss in LDL-R null mice, ritonavir increased food intake, but no difference was observed in gonadal fat weight. Serum leptin levels were significantly lower in females. Ritonavir further suppressed leptin levels in (p

  7. Early skewed distribution of total and HIV-specific CD8+ T-cell memory phenotypes during primary HIV infection is related to reduced antiviral activity and faster disease progression.

    Directory of Open Access Journals (Sweden)

    Yanina Ghiglione

    Full Text Available The important role of the CD8+ T-cells on HIV control is well established. However, correlates of immune protection remain elusive. Although the importance of CD8+ T-cell specificity and functionality in virus control has been underscored, further unraveling the link between CD8+ T-cell differentiation and viral control is needed. Here, an immunophenotypic analysis (in terms of memory markers and Programmed cell death 1 (PD-1 expression of the CD8+ T-cell subset found in primary HIV infection (PHI was performed. The aim was to seek for associations with functional properties of the CD8+ T-cell subsets, viral control and subsequent disease progression. Also, results were compared with samples from Chronics and Elite Controllers. It was found that normal maturation of total and HIV-specific CD8+ T-cells into memory subsets is skewed in PHI, but not at the dramatic level observed in Chronics. Within the HIV-specific compartment, this alteration was evidenced by an accumulation of effector memory CD8+ T (TEM cells over fully differentiated terminal effector CD8+ T (TTE cells. Furthermore, higher proportions of total and HIV-specific CD8+ TEM cells and higher HIV-specific TEM/(TEM+TTE ratio correlated with markers of faster progression. Analysis of PD-1 expression on total and HIV-specific CD8+ T-cells from PHI subjects revealed not only an association with disease progression but also with skewed memory CD8+ T-cell differentiation. Most notably, significant direct correlations were obtained between the functional capacity of CD8+ T-cells to inhibit viral replication in vitro with higher proportions of fully-differentiated HIV-specific CD8+ TTE cells, both at baseline and at 12 months post-infection. Thus, a relationship between preservation of CD8+ T-cell differentiation pathway and cell functionality was established. This report presents evidence concerning the link among CD8+ T-cell function, phenotype and virus control, hence supporting the

  8. HIV-1 Env-Specific Memory and Germinal Center B Cells in C57BL/6 Mice

    Directory of Open Access Journals (Sweden)

    Martina Soldemo

    2014-09-01

    Full Text Available Continued efforts to define the immunogenic properties of the HIV-1 envelope glycoproteins (Env are needed to elicit effective antibody (Ab responses by vaccination. HIV-1 is a highly neutralization-resistant virus due to conformational and glycan shielding of conserved Ab determinants on the virus spike. Elicitation of broadly neutralizing Abs that bind poorly accessible epitope regions on Env is therefore extremely challenging and will likely require selective targeting of specific sub-determinants. To evaluate such approaches there is a pressing need for in vivo studies in both large and small animals, including mice. Currently, most mouse immunization studies are performed in the BALB/c strain; however, the C57BL/6 strain offers improved possibilities for mechanistic studies due to the availability of numerous knock-out strains on this genetic background. Here, we compared Env immunogenicity in BALB/c and C57BL/6 mice and found that the magnitude of the antigen-specific response was somewhat lower in C57BL/6 than in BALB/c mice by ELISA but not significantly different by B cell ELISpot measurements. We then established protocols for the isolation of single Env-specific memory B cells and germinal center (GC B cells from immunized C57BL/6 mice to facilitate future studies of the elicited response at the monoclonal Ab level. We propose that these protocols can be used to gain an improved understanding of the early recruitment of Env-specific B cells to the GC as well as the archiving of such responses in the memory B cell pool following immunization.

  9. Mucosal vaccination with a live recombinant rhinovirus followed by intradermal DNA administration elicits potent and protective HIV-specific immune responses

    Science.gov (United States)

    Tomusange, Khamis; Wijesundara, Danushka; Gummow, Jason; Wesselingh, Steve; Suhrbier, Andreas; Gowans, Eric J.; Grubor-Bauk, Branka

    2016-01-01

    Mucosal immunity is deemed crucial to control sexual transmission of human immunodeficiency virus (HIV). Herein we report the efficacy of a mucosal HIV vaccine strategy comprising intranasal (IN) vaccination with a cocktail of live recombinant human rhinoviruses (HRVs) encoding overlapping fragments of HIV Gag and full length Tat (rHRV-Gag/Tat) followed by intradermal (ID) vaccination with DNA vaccines encoding HIV Gag and Tat (pVAX-Gag-Tat). This heterologous prime-boost strategy will be referred to hereafter as rHRV-DNA. As a control, IN vaccination with wild type (wt)-HRV-A1 followed by a single ID dose of pVAX (wt-HRV-A1/pVAX vaccination) was included. rHRV-DNA vaccination elicited superior multi-functional CD8+T cell responses in lymphocytes harvested from mesenteric lymph nodes and spleens, and higher titres of Tat-specific antibodies in blood and vaginal lavages, and reduced the viral load more effectively after challenge with EcoHIV, a murine HIV challenge model, in peritoneal macrophages, splenocytes and blood compared compared with wt-HRV-A1/pVAX vaccination or administration of 3 ID doses of pVAX-Gag-Tat (3X pVAX-Gag-Tat vaccination). These data provide the first evidence that a rHRV-DNA vaccination regimen can induce HIV-specific immune responses in the gut, vaginal mucosa and systemically, and supports further testing of this regimen in the development of an effective mucosally-targeted HIV-1 vaccine. PMID:27853256

  10. Cellular HIV-1 DNA levels in drug sensitive strains are equivalent to those in drug resistant strains in newly-diagnosed patients in Europe

    NARCIS (Netherlands)

    V.L. Demetriou (Victoria); D.A.M.C. van de Vijver (David); I. Kousiappa (Ioanna); C. Balotta (Claudia); B. Clotet (Bonaventura); Z. Grossman (Zehava); L.B. Jørgensen (Louise); S.Z. Lepej (Snjezana); I. Levy (Itzchak); C. Nielsen (Claus); D. Paraskevis (Dimitrios); M. Poljak (Mario); F. Roman (Francois); L. Ruiz (Lidia); J.C. Schmidt; A.M. Vandamme (Anne Mieke); K. Laethem (Kristel); J. Vercauteren (Jurgen); L.G. Kostrikis (Leondios)

    2010-01-01

    textabstractBackground HIV-1 genotypic drug resistance is an important threat to the success of antiretroviral therapy and transmitted resistance has reached 9% prevalence in Europe. Studies have demonstrated that HIV-1 DNA load in peripheral blood mononuclear cells (PBMC) have a predictive value fo

  11. Controversies in HIV cure research

    Directory of Open Access Journals (Sweden)

    Johnston Rowena

    2012-03-01

    Full Text Available Abstract Background Antiretroviral therapy significantly reduces HIV viral burden and prolongs life, but does not cure HIV infection. The major scientific barrier to a cure is thought to be the persistence of the virus in cellular and/or anatomical reservoirs. Discussion Most efforts to date, including pharmaco, immuno or gene therapy, have failed to cure patients, with the notable exception of a stem cell transplant recipient commonly known as the Berlin patient. This case has revived interest in the potential to cure HIV infection and has highlighted the need to resolve critical questions in the basic, pre-clinical and clinical research spheres as they pertain specifically to efforts to eradicate HIV from the body of an infected person (a sterilizing cure or at least render the need for lifelong antiretroviral therapy obsolete (functional cure. This paper describes ongoing debates in each of these research spheres as they were presented and discussed at a satellite session that took place at the 6th International AIDS Society Conference on HIV Pathogenesis, Treatment and Prevention in Rome in July 2011. Summary The resolution of these debates may have important implications for the search for a cure, the most efficient ways to identify and test promising interventions, and ultimately the availability of such a cure to diverse groups of HIV patients around the world.

  12. Comparative analysis of SIV-specific cellular immune responses induced by different vaccine platforms in rhesus macaques.

    Science.gov (United States)

    Valentin, Antonio; McKinnon, Katherine; Li, Jinyao; Rosati, Margherita; Kulkarni, Viraj; Pilkington, Guy R; Bear, Jenifer; Alicea, Candido; Vargas-Inchaustegui, Diego A; Jean Patterson, L; Pegu, Poonam; Liyanage, Namal P M; Gordon, Shari N; Vaccari, Monica; Wang, Yichuan; Hogg, Alison E; Frey, Blake; Sui, Yongjun; Reed, Steven G; Sardesai, Niranjan Y; Berzofsky, Jay A; Franchini, Genoveffa; Robert-Guroff, Marjorie; Felber, Barbara K; Pavlakis, George N

    2014-11-01

    To identify the most promising vaccine candidates for combinatorial strategies, we compared five SIV vaccine platforms including recombinant canary pox virus ALVAC, replication-competent adenovirus type 5 host range mutant RepAd, DNA, modified vaccinia Ankara (MVA), peptides and protein in distinct combinations. Three regimens used viral vectors (prime or boost) and two regimens used plasmid DNA. Analysis at necropsy showed that the DNA-based vaccine regimens elicited significantly higher cellular responses against Gag and Env than any of the other vaccine platforms. The T cell responses induced by most vaccine regimens disseminated systemically into secondary lymphoid tissues (lymph nodes, spleen) and effector anatomical sites (including liver, vaginal tissue), indicative of their role in viral containment at the portal of entry. The cellular and reported humoral immune response data suggest that combination of DNA and viral vectors elicits a balanced immunity with strong and durable responses able to disseminate into relevant mucosal sites.

  13. Large-scale cellular-resolution gene profiling in human neocortex reveals species-specific molecular signatures

    Science.gov (United States)

    Zeng, Hongkui; Shen, Elaine H.; Hohmann, John G.; Oh, Wook Seung; Bernard, Amy; Royall, Joshua J.; Glattfelder, Katie J.; Sunkin, Susan M.; Morris, John A.; Guillozet-Bongaarts, Angela L.; Smith, Kimberly A.; Ebbert, Amanda J.; Swanson, Beryl; Kuan, Leonard; Page, Damon T.; Overly, Caroline C.; Lein, Ed S.; Hawrylycz, Michael J.; Hof, Patrick R.; Hyde, Thomas M.; Kleinman, Joel E.; Jones, Allan R.

    2012-01-01

    Summary Although there have been major advances in elucidating the functional biology of the human brain, relatively little is known of its cellular and molecular organization. Here we report a large-scale characterization of the expression of ~1,000 genes important for neural functions, by in situ hybridization with cellular resolution in visual and temporal cortices of adult human brains. These data reveal diverse gene expression patterns and remarkable conservation of each individual gene’s expression among individuals (95%), cortical areas (84%), and between human and mouse (79%). A small but substantial number of genes (21%) exhibited species-differential expression. Distinct molecular signatures, comprised of genes both common between species and unique to each, were identified for each major cortical cell type. The data suggest that gene expression profile changes may contribute to differential cortical function across species, in particular, a shift from corticosubcortical to more predominant corticocortical communications in the human brain. PMID:22500809

  14. Computer-based design of novel HIV-1 entry inhibitors: neomycin conjugated to arginine peptides at two specific sites.

    Science.gov (United States)

    Berchanski, Alexander; Lapidot, Aviva

    2009-03-01

    Aminoglycoside-arginine conjugates (AAC and APAC) are multi-target inhibitors of human immunodeficiency virus type-1 (HIV-1). Here, we predict new conjugates of neomycin with two arginine peptide chains binding at specific sites on neomycin [poly-arginine-neomycin-poly-arginine (PA-Neo-PA)]. The rationale for the design of such compounds is to separate two short arginine peptides with neomycin, which may extend the binding region of the CXC chemokine receptor type 4 (CXCR4). We used homology models of CXCR4 and unliganded envelope glycoprotein 120 (HIV-1(IIIB) gp120) and docked PA-Neo-PAs and APACs to these using a multistep docking procedure. The results indicate that PA-Neo-PAs spread over two negatively charged patches of CXCR4. PA-Neo-PA-CXCR4 complexes are energetically more favorable than AACs/APAC-CXCR4 complexes. Notably, our CXCR4 model and docking procedure can be applied to predict new compounds that are either inhibitors of gp120-CXCR4 binding without affecting stromal cell-derived factor 1 alpha (SDF-1 alpha) chemotaxis activity, or inhibitors of SDF-1 alpha-CXCR4 binding resulting in an anti-metastasis effect. We also predict that PA-Neo-PAs and APACs can interfere with CD4-gp120 binding in unliganded conformation.

  15. Dose-response curve slope sets class-specific limits on inhibitory potential of anti-HIV drugs.

    Science.gov (United States)

    Shen, Lin; Peterson, Susan; Sedaghat, Ahmad R; McMahon, Moira A; Callender, Marc; Zhang, Haili; Zhou, Yan; Pitt, Eleanor; Anderson, Karen S; Acosta, Edward P; Siliciano, Robert F

    2008-07-01

    Highly active antiretroviral therapy (HAART) can control HIV-1 replication, but suboptimal treatment allows for the evolution of resistance and rebound viremia. A comparative measure of antiviral activity under clinically relevant conditions would guide drug development and the selection of regimens that maximally suppress replication. Here we show that current measures of antiviral activity, including IC(50) and inhibitory quotient, neglect a key dimension, the dose-response curve slope. Using infectivity assays with wide dynamic range, we show that this slope has noteworthy effects on antiviral activity. Slope values are class specific for antiviral drugs and define intrinsic limitations on antiviral activity for some classes. Nucleoside reverse transcriptase inhibitors and integrase inhibitors have slopes of approximately 1, characteristic of noncooperative reactions, whereas non-nucleoside reverse transcriptase inhibitors, protease inhibitors and fusion inhibitors unexpectedly show slopes >1. Instantaneous inhibitory potential (IIP), the log reduction in single-round infectivity at clinical drug concentrations, is strongly influenced by slope and varies by >8 logs for anti-HIV drugs. IIP provides a more accurate measure of antiviral activity and in general correlates with clinical outcomes. Only agents with slopes >1 achieve high-level inhibition of single-round infectivity, a finding with profound implications for drug and vaccine development.

  16. αEnv-decorated phosphatidylserine liposomes trigger phagocytosis of HIV-virus-like particles in macrophages.

    Science.gov (United States)

    Gramatica, Andrea; Petazzi, Roberto A; Lehmann, Maik J; Ziomkowska, Joanna; Herrmann, Andreas; Chiantia, Salvatore

    2014-07-01

    Macrophages represent an important cellular target of HIV-1. Interestingly, they are also believed to play a potential role counteracting its infection. However, HIV-1 is known to impair macrophage immune functions such as antibody-mediated phagocytosis. Here, we present immunoliposomes that can bind HIV-1 virus-like particles (HIV-VLPs) while being specifically phagocytosed by macrophages, thus allowing the co-internalization of HIV-VLPs. These liposomes are decorated with anti-Env antibodies and contain phosphatidylserine (PS). PS mediates liposome internalization by macrophages via a mechanism not affected by HIV-1. Hence, PS-liposomes mimic apoptotic cells and are internalized into the macrophages due to specific recognition, carrying the previously bound HIV-VLPs. With a combination of flow cytometry, confocal live-cell imaging and electron microscopy we demonstrate that the PS-immunoliposomes presented here are able to elicit efficient HIV-VLPs phagocytosis by macrophages and might represent a new nanotechnological approach to enhance HIV-1 antigen presentation and reduce the ongoing inflammation processes. This team of authors demonstrate that specific phosphatidylserin immunoliposomes are able to elicit efficient phagocytosis of HIV-virus-like particle by macrophages and might represent a new nanomedicine approach to enhance HIV-1 antigen presentation and reduce ongoing inflammation processes. Copyright © 2014 Elsevier Inc. All rights reserved.

  17. Functional characterization of two scFv-Fc antibodies from an HIV controller selected on soluble HIV-1 Env complexes: a neutralizing V3- and a trimer-specific gp41 antibody.

    Directory of Open Access Journals (Sweden)

    Maria Trott

    Full Text Available HIV neutralizing antibodies (nAbs represent an important tool in view of prophylactic and therapeutic applications for HIV-1 infection. Patients chronically infected by HIV-1 represent a valuable source for nAbs. HIV controllers, including long-term non-progressors (LTNP and elite controllers (EC, represent an interesting subgroup in this regard, as here nAbs can develop over time in a rather healthy immune system and in the absence of any therapeutic selection pressure. In this study, we characterized two particular antibodies that were selected as scFv antibody fragments from a phage immune library generated from an LTNP with HIV neutralizing antibodies in his plasma. The phage library was screened on recombinant soluble gp140 envelope (Env proteins. Sequencing the selected peptide inserts revealed two major classes of antibody sequences. Binding analysis of the corresponding scFv-Fc derivatives to various trimeric and monomeric Env constructs as well as to peptide arrays showed that one class, represented by monoclonal antibody (mAb A2, specifically recognizes an epitope localized in the pocket binding domain of the C heptad repeat (CHR in the ectodomain of gp41, but only in the trimeric context. Thus, this antibody represents an interesting tool for trimer identification. MAb A7, representing the second class, binds to structural elements of the third variable loop V3 and neutralizes tier 1 and tier 2 HIV-1 isolates of different subtypes with matching critical amino acids in the linear epitope sequence. In conclusion, HIV controllers are a valuable source for the selection of functionally interesting antibodies that can be selected on soluble gp140 proteins with properties from the native envelope spike.

  18. 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.

  19. Toxicity evaluation of e-juice and its soluble aerosols generated by electronic cigarettes using recombinant bioluminescent bacteria responsive to specific cellular damages.

    Science.gov (United States)

    Bharadwaj, Shiv; Mitchell, Robert J; Qureshi, Anjum; Niazi, Javed H

    2017-04-15

    Electronic-cigarettes (e-cigarette) are widely used as an alternative to traditional cigarettes but their safety is not well established. Herein, we demonstrate and validate an analytical method to discriminate the deleterious effects of e-cigarette refills (e-juice) and soluble e-juice aerosol (SEA) by employing stress-specific bioluminescent recombinant bacterial cells (RBCs) as whole-cell biosensors. These RBCs carry luxCDABE-operon tightly controlled by promoters that specifically induced to DNA damage (recA), superoxide radicals (sodA), heavy metals (copA) and membrane damage (oprF). The responses of the RBCs following exposure to various concentrations of e-juice/SEA was recorded in real-time that showed dose-dependent stress specific-responses against both the e-juice and vaporized e-juice aerosols produced by the e-cigarette. We also established that high doses of e-juice (4-folds diluted) lead to cell death by repressing the cellular machinery responsible for repairing DNA-damage, superoxide toxicity, ion homeostasis and membrane damage. SEA also caused the cellular damages but the cells showed enhanced bioluminescence expression without significant growth inhibition, indicating that the cells activated their global defense system to repair these damages. DNA fragmentation assay also revealed the disintegration of total cellular DNA at sub-toxic doses of e-juice. Despite their state of matter, the e-juice and its aerosols induce cytotoxicity and alter normal cellular functions, respectively that raises concerns on use of e-cigarettes as alternative to traditional cigarette. The ability of RBCs in detecting both harmful effects and toxicity mechanisms provided a fundamental understanding of biological response to e-juice and aerosols.

  20. CONSECUTIVE IMMUNIZATION WITH RECOMBINANT FOWLPOX VIRUS AND PLASMID DNA FOR ENHANCING CELLULAR AND HUMORAL IMMUNITY

    Institute of Scientific and Technical Information of China (English)

    罗坤; 金宁一; 郭志儒; 秦云龙; 郭炎; 方厚华; 安汝国; 殷震

    2001-01-01

    To investigate the influence of consecutive immunization on cellular and humoral immunity in mice. Methods: We evaluated a consecutive immunization strategy of priming with recombinant fowlpox virus vUTALG and boosting with plasmid DNA pcDNAG encoding HIV-1 capsid protein Gag. Results: In immunized mice, the number of CD4+ T cells from splenic lymphocytes increased significantly and the proliferation response of splenocytes to ConA and LPS elevated markedly and HIV-1-specific antibody response could be induced. Conclusion: Consecutive immunization could increase cellular and humoral immunity responses in mice.

  1. Dynamic changes of cellular HIV-1 DNA quantification during highly active antiretroviral therapy in Chinese HIV infected individuals%艾滋病抗病毒治疗中外周血细胞病毒库的动态变化及其意义

    Institute of Scientific and Technical Information of China (English)

    陈霞; 郑煜煌; 加路; 何艳; 周华英; 谌资; 罗艳; 贺波; 贺梅

    2013-01-01

    Objective:To observe the dynamic changes of 3 types of viral reservoir cells (NK cells,T lymphocytes and monocytes),and its relationship with treatment effect in Chinese HIV-1 infected patients receiving highly active antiretroviral treatment (HAART) for 2 years.Methods:A total of 40 chronic HIV-1-infected adults who initiated HAART were enrolled in this study and followed up for 2 years.Peripheral whole blood was obtained from each patient at baseline (0 month),6,12,18 and 24 months.Real-time fluorescent quantitative PCR was used to detect the HIV-1 RNA in the plasma and HIV-1 DNA in NK cells,T lymphocytes and monocytes.All the data were statistically analyzed.Results:CD4 count increased with the decrease of the viral load during HAART.After HAART initiation,HIV-1 DNA showed a significant decrease in NK cells,T lymphocytes and monocytes.The HIV-1 DNA from T lymphocytes,NK cells and monocytes correlated positively with the HIV-1 RNA (P<0.05) while NK cells and T lymphocytes correlated negatively with CD4+T cell count.However we did not find significant correlation between CD4+T cell count and HIV-1 DNA in monocytes at the baseline of HAART.Conclusion:This study found that NK cell was an important HIV cellular reservoir besides T lymphocytes and monocytes.T lymphocytes may be the main long lasting HIV reservoir.HIV-1 proviral DNA may play an important role in the efficacy of treatment and monitoring the disease progression.%目的:观察中国HIV-1感染者和AIDS病(HIV/AIDS)患者在两年高效抗反转录病毒治疗(highly active antiretroviral therapy,HAART)过程中,外周血NK细胞、T淋巴细胞以及单核细胞3种HIV-1病毒储存库的动态变化及其与治疗效果的关系.方法:40例初次接受HAART的HIV/AIDS患者被纳入本研究并随访2年.在启动治疗0,6,12,18,24个月后,检测其外周血HIV-1 RNA病毒载量,CD4+T细胞数量,NK细胞、单核细胞和T淋巴细胞内的HIV-1 DNA水平,对数据进行统计学

  2. Mycobacterium avium and purified protein derivative-specific cytotoxicity mediated by CD4+ lymphocytes from healthy HIV-seropositive and-seronegative individuals

    DEFF Research Database (Denmark)

    Ravn, P; Pedersen, B K

    1996-01-01

    to respond to mycobacterial antigens. The immunological dysfunction leading to reduced mycobacterial-specific cytotoxic activity in healthy HIV-seropositive subjects is caused either by a reduction in the number of antigen-responsive CD4+ T cells (memory) or by an impairment of their ability to respond...

  3. Specific Human and Candida Cellular Interactions Lead to Controlled or Persistent Infection Outcomes during Granuloma-Like Formation.

    Science.gov (United States)

    Misme-Aucouturier, Barbara; Albassier, Marjorie; Alvarez-Rueda, Nidia; Le Pape, Patrice

    2017-01-01

    A delayed type of multicellular process could be crucial during chronic candidiasis in determining the course of infection. This reaction, consisting of organized immune cells surrounding the pathogen, initiates an inflammatory response to avoid fungal dissemination. The goal of the present study was to examine, at an in vitro cellular scale, Candida and human immune cell interaction dynamics during a long-term period. By challenging human peripheral blood immune cells from 10 healthy donors with 32 Candida albicans and non-albicans (C. glabrata, C. tropicalis, C. parapsilosis, C. dubliniensis, C. lusitaniae, C. krusei, and C. kefyr) clinical isolates, we showed that Candida spp. induced the formation of granuloma-like structures within 6 days after challenge, but their sizes and the respective fungal burdens differed according to the Candida species. These two parameters are positively correlated. Phenotypic characteristics, such as hypha formation and higher axenic growth rate, seem to contribute to yeast persistence within granuloma-like structures. We showed an interindividual variability of the human response against Candida spp. Higher proportions of neutrophils and elevated CD4(+)/CD8(+) T cell ratios during the first days after challenge were correlated with early production of gamma interferon (IFN-γ) and associated with controlled infection. In contrast, the persistence of Candida could result from upregulation of proinflammatory cytokines such as interleukin-6 (IL-6), IFN-γ, and tumor necrosis factor alpha (TNF-α) and a poor anti-inflammatory negative feedback (IL-10). Importantly, regulatory subsets of NK cells and CD4(lo) CD8(hi) doubly positive (DP) lymphocytes at late stage infiltrate granuloma-like structures and could correlate with the IL-10 and TNF-α production. These data offer a base frame to explain cellular events that guide infection control or fungal persistence. Copyright © 2016 Misme-Aucouturier et al.

  4. Higher specificity of nucleic acid sequence-based amplification isothermal technology than of real-time PCR for quantification of HIV-1 RNA on dried blood spots.

    Science.gov (United States)

    Mercier-Delarue, Severine; Vray, Muriel; Plantier, Jean Christophe; Maillard, Theodora; Adjout, Zidan; de Olivera, Fabienne; Schnepf, Nathalie; Maylin, Sarah; Simon, Francois; Delaugerre, Constance

    2014-01-01

    Dried blood spots (DBS) are widely proposed as a plasma surrogate for monitoring antiretroviral treatment efficacy based on the HIV-1 RNA level (viral load [VL]) in resource-limited settings. Interfering coamplification of cell-associated HIV-1 DNA during reverse transcription (RT)-PCR can be avoided by using nucleic acid sequence-based amplification (NASBA) technology, which is based on an RNA template and isothermic conditions. We analyzed VL values obtained with DBS and plasma samples by comparing isothermic NASBA (NucliSENS EasyQ HIV-1 V2.0; bioMérieux) with real-time RT-PCR (Cobas TaqMan HIV-1 V2.0; Roche). Samples from 197 HIV-1-infected patients were tested (non-B subtypes in 51% of the cases). Nucleic acid extractions were performed by use of NucliSENS EasyMAG (bioMérieux) and Cobas AmpliPrep (Roche) before the NASBA and RT-PCR quantifications, respectively. Both quantification assays have lower limits of detection of 20 (1.3) and 800 (2.9) log10 copies/ml (log) in plasma and DBS, respectively. The mean (DBS minus plasma) differences were -0.39 and -0.46 log, respectively, for RT-PCR and NASBA. RT-PCR on DBS identified virological failure in 122 of 126 patients (sensitivity, 97%) and viral suppression in 58 of 70 patients (specificity, 83%), yielding 12 false-positive results (median, 3.2 log). NASBA on DBS identified virological failure in 85 of 96 patients (sensitivity, 89%) and viral suppression in 95 of 97 patients (specificity, 98%) and yielded 2 false-positive results (3.0 log for both). Both technologies detected HIV-1 RNA in DBS at a threshold of 800 copies/ml. This higher specificity of NASBA technology could avoid overestimation of poor compliance or the emergence of resistance when monitoring antiretroviral efficacy with the DBS method.

  5. HIV gp120 induces, NF-kappaB dependent, HIV replication that requires procaspase 8.

    Directory of Open Access Journals (Sweden)

    Gary D Bren

    Full Text Available BACKGROUND: HIV envelope glycoprotein gp120 causes cellular activation resulting in anergy, apoptosis, proinflammatory cytokine production, and through an unknown mechanism, enhanced HIV replication. METHODOLOGY/PRINCIPAL FINDINGS: We describe that the signals which promote apoptosis are also responsible for the enhanced HIV replication. Specifically, we demonstrate that the caspase 8 cleavage fragment Caspase8p43, activates p50/p65 Nuclear Factor kappaB (NF-kappaB, in a manner which is inhibited by dominant negative IkappaBalpha. This caspase 8 dependent NF-kappaB activation occurs following stimulation with gp120, TNF, or CD3/CD28 crosslinking, but these treatments do not activate NF-kappaB in cells deficient in caspase 8. The Casp8p43 cleavage fragment also transactivates the HIV LTR through NF-kappaB, and the absence of caspase 8 following HIV infection greatly inhibits HIV replication. CONCLUSION/SIGNIFICANCE: Gp120 induced caspase 8 dependent NF-kappaB activation is a novel pathway of HIV replication which increases understanding of the biology of T-cell death, as well as having implications for understanding treatment and prevention of HIV infection.

  6. A novel granulocyte-specific α integrin is essential for cellular immunity in the silkworm Bombyx mori.

    Science.gov (United States)

    Zhang, Kui; Tan, Juan; Xu, Man; Su, Jingjing; Hu, Renjian; Chen, Yibiao; Xuan, Fan; Yang, Rui; Cui, Hongjuan

    2014-12-01

    Haemocytes play crucial roles in immune responses and survival in insects. Specific cell markers have proven effective in clarifying the function and haematopoiesis of haemocytes. The silkworm Bombyx mori is a good model for studying insect haemocytes; however, little is known about haemocyte-specific markers or their functions in silkworm. In this study, we identified the α subunit of integrin, BmintegrinαPS3, as being specifically and highly expressed in silkworm haemocytes. Immunofluorescence analysis validated the specificity of BmintegrinαPS3 in larval granulocytes. Further analyses indicated that haemocytes dispersed from haematopoietic organs (HPOs) into the circulating haemolymph could differentiate into granulocytes. In addition, the processes of encapsulation and phagocytosis were controlled by larval granulocytes. Our work demonstrated that BmintegrinαPS3 could be used as a specific marker for granulocytes and could be applied to future molecular cell biology studies.

  7. Human immunodeficiency virus type 1 specific cytotoxic T lymphocyte responses in Chinese infected with HIV-1 B'/C Recombinant (CRF07_BC

    Directory of Open Access Journals (Sweden)

    Yu Xu G

    2007-08-01

    Full Text Available Abstract Background The characterization of HIV-1-specific T cell responses in people infected with locally circulating HIV-1 strain will facilitate the development of HIV-1 vaccine. Sixty intravenous drug users infected with HIV-1 circulating recombinant form 07_BC (CRF07_BC, which has been spreading rapidly in western China from north to south, were recruited from Xinjiang, China to assess the HIV-1-specific T cell responses at single peptide level with overlapping peptides (OLP covering the whole concensus clades B and C proteome. Results The median of the total magnitude and total number of OLPs recognized by CTL responses were 10925 SFC/million PBMC and 25 OLPs, respectively, when tested by clade C peptides, which was significantly higher than when tested by clade B peptides. The immunodominant regions, which cover 14% (58/413 of the HIV-1 proteome, are widely distributed throughout the HIV-1 proteome except in Tat, Vpu and Pol-PR, with Gag, Pol-RT, Pol-Int and Nef being most frequently targeted. The subdominant epitopes are mostly located in p24, Nef, integrase, Vpr and Vif. Of the responses directed to clade C OLPs, 61.75% (972/1574 can be observed when tested with corresponding clade B OLPs. However, Pol-PR and Vpu tend to be targeted in the clade B sequence rather than the clade C sequence, which is in line with the recombinant pattern of CRF07_BC. Stronger and broader CTL responses in subjects with CD4 cell counts ranging from 200 to 400/mm3 were observed when compared to those with less than 200/mm3 or more than 400/mm3, though there have been no significant correlations identified between the accumulative CTL responses or overall breadth and CD4 cell count or plasma viral load. Conclusion This is the first study conducted to comprehensively address T cell responses in Chinese subjects infected with HIV-1 CRF07_BC in which subtle differences in cross-reactivity were observed, though similar patterns of overall immune responses were

  8. HIV-1 proteins in infected cells determine the presentation of viral peptides by HLA class I and class II molecules and the nature of the cellular and humoral antiviral immune responses--a review.

    Science.gov (United States)

    Becker, Y

    1994-07-01

    The goals of molecular virology and immunology during the second half of the 20th century have been to provide the conceptual approaches and the tools for the development of safe and efficient virus vaccines for the human population. The success of the vaccination approach to prevent virus epidemics was attributed to the ability of inactivated and live virus vaccines to induce a humoral immune response and to produce antiviral neutralizing antibodies in the vaccinees. The successful development of antiviral vaccines and their application to most of the human population led to a marked decrease in virus epidemics around the globe. Despite this remarkable achievement, the developing epidemics of HIV-caused AIDS (accompanied by activation of latent herpesviruses in AIDS patients), epidemics of Dengue fever, and infections with respiratory syncytial virus may indicate that conventional approaches to the development of virus vaccines that induce antiviral humoral responses may not suffice. This may indicate that virus vaccines that induce a cellular immune response, leading to the destruction of virus-infected cells by CD8+ cytotoxic T cells (CTLs), may be needed. Antiviral CD8+ CTLs are induced by viral peptides presented within the peptide binding grooves of HLA class I molecules present on the surface of infected cells. Studies in the last decade provided an insight into the presentation of viral peptides by HLA class I molecules to CD8+ T cells. These studies are here reviewed, together with a review of the molecular events of virus replication, to obtain an overview of how viral peptides associate with the HLA class I molecules. A similar review is provided on the molecular pathway by which viral proteins, used as subunit vaccines or inactivated virus particles, are taken up by endosomes in the endosome pathway and are processed by proteolytic enzymes into peptides that interact with HLA class II molecules during their transport to the plasma membrane of antigen

  9. Differences in the mannose oligomer specificities of the closely related lectins from Galanthus nivalis and Zea mays strongly determine their eventual anti-HIV activity

    Directory of Open Access Journals (Sweden)

    Fouquaert Elke

    2011-02-01

    Full Text Available Abstract Background In a recent report, the carbohydrate-binding specificities of the plant lectins Galanthus nivalis (GNA and the closely related lectin from Zea mays (GNAmaize were determined by glycan array analysis and indicated that GNAmaize recognizes complex-type N-glycans whereas GNA has specificity towards high-mannose-type glycans. Both lectins are tetrameric proteins sharing 64% sequence similarity. Results GNAmaize appeared to be ~20- to 100-fold less inhibitory than GNA against HIV infection, syncytia formation between persistently HIV-1-infected HuT-78 cells and uninfected CD4+ T-lymphocyte SupT1 cells, HIV-1 capture by DC-SIGN and subsequent transmission of DC-SIGN-captured virions to uninfected CD4+ T-lymphocyte cells. In contrast to GNA, which preferentially selects for virus strains with deleted high-mannose-type glycans on gp120, prolonged exposure of HIV-1 to dose-escalating concentrations of GNAmaize selected for mutant virus strains in which one complex-type glycan of gp120 was deleted. Surface Plasmon Resonance (SPR analysis revealed that GNA and GNAmaize interact with HIV IIIB gp120 with affinity constants (KD of 0.33 nM and 34 nM, respectively. Whereas immobilized GNA specifically binds mannose oligomers, GNAmaize selectively binds complex-type GlcNAcβ1,2Man oligomers. Also, epitope mapping experiments revealed that GNA and the mannose-specific mAb 2G12 can independently bind from GNAmaize to gp120, whereas GNAmaize cannot efficiently bind to gp120 that contained prebound PHA-E (GlcNAcβ1,2man specific or SNA (NeuAcα2,6X specific. Conclusion The markedly reduced anti-HIV activity of GNAmaize compared to GNA can be explained by the profound shift in glycan recognition and the disappearance of carbohydrate-binding sites in GNAmaize that have high affinity for mannose oligomers. These findings underscore the need for mannose oligomer recognition of therapeutics to be endowed with anti-HIV activity and that mannose, but

  10. Vaccination for 2009 pandemic H1N1 influenza A did not induce conserved epitope-specific memory CD8 T cell responses in HIV+ northern Thai children.

    Science.gov (United States)

    Chawansuntati, Kriangkrai; Aurpibul, Linda; Wipasa, Jiraprapa

    2015-09-11

    The influenza virus causes severe illness in susceptible populations, including children and people living with human immunodeficiency virus (HIV). Here, we investigated cell-mediated immune responses (CMI) against influenza CD8 T cell conserved epitopes in HIV-infected (HIV+) northern Thai children following the 2009 pandemic H1N1 influenza A vaccination. Sixty HIV+ children were vaccinated with two doses of the 2009 pandemic influenza vaccine and their CD8T cell responses were assessed. We found no significant differences in the increase of cytokines-producing and CD107a-expressing CD8+ T cells or CD8+ memory T cells in response to pooled conserved epitopes stimulation in vitro between children with different serologic responses to the vaccine at all time points of the study. Our results suggest that the 2009 pandemic H1N1 vaccine did not induce the conserved epitope-specific immune responses in HIV+ children. Vaccine design and vaccination strategy against influenza in these populations warrant further studies.

  11. CNS-specific regulatory elements in brain-derived HIV-1 strains affect responses to latency-reversing agents with implications for cure strategies

    Science.gov (United States)

    Gray, L R; Cowley, D; Welsh, C; Lu, H K; Brew, B J; Lewin, S R; Wesselingh, S L; Gorry, P R; Churchill, M J

    2016-01-01

    Latency-reversing agents (LRAs), including histone deacetylase inhibitors (HDACi), are being investigated as a strategy to eliminate latency in HIV-infected patients on suppressive antiretroviral therapy. The effectiveness of LRAs in activating latent infection in HIV strains derived from the central nervous system (CNS) is unknown. Here we show that CNS-derived HIV-1 strains possess polymorphisms within and surrounding the Sp transcription factor motifs in the long terminal repeat (LTR). These polymorphisms result in decreased ability of the transcription factor specificity protein 1 to bind CNS-derived LTRs, reducing the transcriptional activity of CNS-derived viruses. These mutations result in CNS-derived viruses being less responsive to activation by the HDACi panobinostat and romidepsin compared with lymphoid-derived viruses from the same subjects. Our findings suggest that HIV-1 strains residing in the CNS have unique transcriptional regulatory mechanisms, which impact the regulation of latency, the consideration of which is essential for the development of HIV-1 eradication strategies. PMID:26303660

  12. Marked depletion of glycosylation sites in HIV-1 gp120 under selection pressure by the mannose-specific plant lectins of Hippeastrum hybrid and Galanthus nivalis.

    Science.gov (United States)

    Balzarini, Jan; Van Laethem, Kristel; Hatse, Sigrid; Froeyen, Matheus; Van Damme, Els; Bolmstedt, Anders; Peumans, Willy; De Clercq, Erik; Schols, Dominique

    2005-05-01

    The plant lectins from Hippeastrum hybrid (HHA) and Galanthus nivalis (GNA) are 50,000-D tetramers showing specificity for alpha-(1,3) and/or alpha-(1,6)-mannose oligomers. They inhibit HIV-1 infection at a 50% effective concentration of 0.2 to 0.3 microg/ml. Escalating HHA or GNA concentrations (up to 500 microg/ml) led to the isolation of three HIV-1(III(B)) strains in CEM T cell cultures that were highly resistant to HHA and GNA, several other related mannose-specific plant lectins, and the monoclonal antibody 2G12, modestly resistant to the mannose-specific cyanovirin, which is derived from a blue-green alga, but fully susceptible to other HIV entry inhibitors as well as HIV reverse transcriptase inhibitors. These mutant virus strains were devoid of up to seven or eight of 22 glycosylation sites in the viral envelope glycoprotein gp120 because of mutations at the Asn or Thr/Ser sites of the N-glycosylation motifs. In one of the strains, a novel glycosylation site was created near a deleted glycosylation site. The affected glycosylation sites were predominantly clustered in regions of gp120 that are not involved in the direct interaction with either CD4, CCR5, CXCR4, or gp41. The mutant viruses containing the deleted glycosylation sites were markedly more infectious in CEM T-cell cultures than wild-type virus.

  13. Cellular and subcellular localization of the neuron-specific plasma membrane calcium ATPase PMCA1a in the rat brain.

    Science.gov (United States)

    Kenyon, Katharine A; Bushong, Eric A; Mauer, Amy S; Strehler, Emanuel E; Weinberg, Richard J; Burette, Alain C

    2010-08-15

    Regulation of intracellular calcium is crucial both for proper neuronal function and survival. By coupling ATP hydrolysis with Ca(2+) extrusion from the cell, the plasma membrane calcium-dependent ATPases (PMCAs) play an essential role in controlling intracellular calcium levels in neurons. In contrast to PMCA2 and PMCA3, which are expressed in significant levels only in the brain and a few other tissues, PMCA1 is ubiquitously distributed, and is thus widely believed to play a "housekeeping" function in mammalian cells. Whereas the PMCA1b splice variant is predominant in most tissues, an alternative variant, PMCA1a, is the major form of PMCA1 in the adult brain. Here, we use immunohistochemistry to analyze the cellular and subcellular distribution of PMCA1a in the brain. We show that PMCA1a is not ubiquitously expressed, but rather is confined to neurons, where it concentrates in the plasma membrane of somata, dendrites, and spines. Thus, rather than serving a general housekeeping function, our data suggest that PMCA1a is a calcium pump specialized for neurons, where it may contribute to the modulation of somatic and dendritic Ca(2+) transients.

  14. HIV-specific cvtotoxic T-lymphocyte responses in patients co-infected with HIV and HCV%艾滋病病毒/丙型肝炎病毒双重感染者的艾滋病病毒特异性CTL应答

    Institute of Scientific and Technical Information of China (English)

    康文臻; 黄德东; 李媛; 庄严; 翟嵩; 赵柯; 谢玉梅; 孙永涛

    2011-01-01

    Objective To investigate the features of HIV-spocific cytotoxic T-lymphocyte (CTL) responses in patients co-infected with HIV and HCV in China. Methods The patients were divided into 2 groups, HIV/HCV co-infected group (n=22) and simply HIV infected group (n=20). The HIV-l-specific CTL responses were analyzed in an ELISPOT assay by using peptides spanning the entire HIV-1 Clade B consensus sequence. Comparison was made between the difference of HIV specific CTL of HIV/HCV coinfectied group and simply HIV infected group. Results In comparison of the response between HIV/HCV co-infected and simply HIV infected group, the magnitude and frequency of HIV specific CTL was roughly identical with some difference found at singlepeptide level. In HIV/HCV co-infected group, the magnitude and frequency of HIV specific CTL in Gag was higher than those in HIV group. There was positive linear correlation between the magnitude and the frequency of HIV specific CTL in the two groups.Gag and Nef were the most frequently targeted proteins. There was no significant correlation between the total responses of HIV specific CTL and CD4+T cell count. Conclusion HIV-l-specifie CTL may play an important role in aggravating HIV in patients with HIV/HCV co-infection.%目的 探讨中国艾滋病病毒/丙型肝炎病毒(HIV/HCV)双重感染患者HIV特异性细胞毒性T淋巴细胞(CTL)应答的特征.方法 观察对象为HIV/HCV双重患者、单纯HIV感染者.以HIV-1 B亚型构建的全基因组肽库作为抗原,通过酶联免疫斑点(ELISPOT)法检测HIV/AIDS患者HIV特异性CTL应答.并对HIV/HCV双重感染患者的HIV特异性CTL应答进行相关性分析.结果 HIV/HCV双重感染组和单纯HIV感染组的HIV特异性CTL应答强度与频率在肽段水平存在一定差异,与单纯HIV感染组相比,合并HCV感染组反应增强的肽段主要集中在Gag.两组特异性CTL应答强度与频率均呈明显正相关,且合并HCV感染组较单纯感染组正相关性增强

  15. Molecular characterization of the variable heavy and light chain regions of five HIV-1 specific human monoclonal antibodies.

    NARCIS (Netherlands)

    E.M.M. van der Donk; M. Schutten (Martin); A.D.M.E. Osterhaus (Albert); R.W.J. van der Heijden (Roger)

    1994-01-01

    textabstractWe have reported the generation and characterization of four HIV-1 neutralizing human monoclonal antibodies. Three antibodies recognize a conformational epitope within the CD4-binding site of HIV-1 gp120 and one recognizes a linear epitope located within the hypervariable V3 domain of gp

  16. Application of Mycobacterium Leprae-specific cellular and serological tests for the differential diagnosis of leprosy from confounding dermatoses.

    Science.gov (United States)

    Freitas, Aline Araújo; Hungria, Emerith Mayra; Costa, Maurício Barcelos; Sousa, Ana Lúcia Osório Maroccolo; Castilho, Mirian Lane Oliveira; Gonçalves, Heitor Sá; Pontes, Maria Araci Andrade; Duthie, Malcolm S; Stefani, Mariane Martins Araújo

    2016-10-01

    Mycobacterium leprae-specific serological and cell-mediated-immunity/CMI test were evaluated for the differential diagnosis of multibacillary/MB, and paucibacillary/PB leprosy from other dermatoses. Whole-blood assay/WBA/IFNγ stimulated with LID-1 antigen and ELISA tests for IgG to LID-1 and IgM to PGL-I were performed. WBA/LID-1/IFNγ production was observed in 72% PB, 11% MB leprosy, 38% dermatoses, 40% healthy endemic controls/EC. The receiver operating curve/ROC for WBA/LID-1 in PB versus other dermatoses showed 72.5% sensitivity, 61.5% specificity and an area-under-the-curve/AUC=0.75; 74% positive predictive value/PPV, 59% negative predictive value/NPV. Anti PGL-I serology was positive in 67% MB, 8% PB leprosy, 6% of other dermatoses; its sensitivity for MB=66%, specificity=93%, AUC=0.89; PPV=91%, NPV=72%. Anti-LID-1 serology was positive in 87% MB, 7% PB leprosy, all other participants were seronegative; 87.5% sensitivity for MB, 100% specificity, AUC=0.97; PPV=100%, NPV=88%. In highly endemic areas anti-LID-1/PGL-I serology and WBA/LID-1-represent useful tools for the differential diagnosis of leprosy from other confounding dermatoses.

  17. Fat-specific protein 27 modulates nuclear factor of activated T cells 5 and the cellular response to stress

    Science.gov (United States)

    Fat-specific protein 27 (FSP27), a member of the cell death-inducing DNA fragmentation factor a-like effector (Cide) family, is highly expressed in adipose tissues and is a lipid droplet (LD)-associated protein that induces the accumulation of LDs. Using a yeast two-hybrid system to examine potentia...

  18. Epitope target structures of Fc-mediated effector function during HIV-1 acquisition.

    Science.gov (United States)

    Lewis, George K; Guan, Yongjun; Kamin-Lewis, Roberta; Sajadi, Mohammad; Pazgier, Marzena; Devico, Anthony L

    2014-05-01

    This review analyzes recent studies suggesting that highly conserved epitopes in the HIV-1 Env trimer are targets of potentially protective nonneutralizing antibodies that mediate antibody-dependent cellular cytotoxicity. Recent studies in both non-human primates and humans suggest that nonneutralizing antibodies play a role in blocking infection with hybrid simian HIV (SHIV)/simian immunodeficiency virus (SIV) or HIV-1 by Fc-mediated effector function, in particular antibody-dependent cellular cytotoxicity. Further, several studies implicate highly conserved epitopes in the C1 region of gp120 as targets of these antibodies. However, these suggestions are controversial, as passive immunization studies do not indicate that such antibodies can block acquisition in non-human primates. Potential reasons for this discrepancy are discussed in the structural context of potent antibody-dependent cellular cytotoxicity epitopes on target cells during the narrow window of opportunity when antibodies can block HIV-1 acquisition. Cumulative evidence suggests that, in addition to virus neutralization, Fc-mediated effector responses to highly conserved epitopes in the HIV-1 trimer play distinct as well as overlapping roles in blocking HIV-1 acquisition. Evidence will be discussed as to whether nonneutralizing antibodies specific for epitopes on the HIV-1 Env trimer that become exposed during viral entry contribute significantly to blocking HIV-1 acquisition.

  19. Overcoming HIV-1 resistance to RNA interference.

    Science.gov (United States)

    Boden, Daniel; Pusch, Oliver; Ramratnam, Bharat

    2007-05-01

    RNAi refers to the sequence-specific degradation of RNA that follows the cellular introduction of homologous short interfering (si) RNA. RNAi has emerged as a powerful tool to probe the function of genes of known sequence in vitro and in vivo. Advances in vector design permit the effective expression of siRNA in human cells. Numerous recent investigations have described the ability of RNAi to decrease the replication of human immunodeficiency virus type 1 (HIV-1) in lymphocytic cells using siRNA targeting viral (e.g. tat, gag, rev) and host (e.g. CCR5, CD4) proteins. Can RNAi be used as a form of genetic therapy for HIV-1 infection? Recent data indicate that the dynamic replication kinetics of HIV-1 pose a considerable barrier to achieving durable virus suppression by RNAi with the rapid emergence of HIV-1 mutants resistant to siRNA. This review summarizes recent work on HIV-1 specific RNAi with a focus on potential strategies to overcome HIV-1 resistance to RNAi.

  20. Co-administration of Interleukin-2 Enhances Cellular and Humoral Immune Responses to HIV Vaccine DNA Prime/MVA Boost Regime

    Institute of Scientific and Technical Information of China (English)

    JIANG Chun-lai; YU Xiang-hui; WU Yong-ge; LI Wei; KONG Wei

    2005-01-01

    Interleukine-2(IL-2) is a growth factor for antigen-stimulated T lymphocytes and is responsible for T-cell clonal expansion after antigen recognition. It has been demonstrated that DNA vaccine-elicited immune responses in mice could be augmented substantially by using either an IL-2 protein or a plasmid expressing IL-2. Twenty mice, divided into four experimental groups, were immunized with: (1) sham plasmid; (2) HIV-1 DNA vaccine alone; (3) HIV-1 DNA vaccine and IL-2 protein; or (4) HIV-1 DNA vaccine and IL-2 plasmid, separately. All the groups were immunized 3 times at a 2-week interval. Fourteen days after the last DNA vaccine injection, recombinant MVA was injected into all the mice except those in group 1. ELISA and ELISPOT were employed to investigate the effect of IL-2 on DNA vaccine immune responses. The obtained results strongly indicate that the efficacy of HIV vaccine can be enhanced by co-administration of a plasmid encoding IL-2.

  1. Anti-HIV-1 ADCC antibodies following latency reversal and treatment interruption

    DEFF Research Database (Denmark)

    Lee, Wen Shi; Kristensen, Anne B; Rasmussen, Thomas A

    2017-01-01

    There is growing interest in utilizing antibody-dependent cellular cytotoxicity (ADCC) to eliminate infected cells following reactivation from HIV-1 latency. A potential barrier is that HIV-1-specific ADCC antibodies decline in patients on long-term antiretroviral therapy (ART) and may...... not be sufficient to eliminate reactivated latently infected cells. It is not known whether reactivation from latency with latency-reversing agents (LRA) could provide sufficient antigenic stimulus to boost HIV-1-specific ADCC. We find that treatment with the LRA panobinostat or a short analytical treatment......) trial robustly boosted HIV-1 gp120-specific Fc receptor-binding antibodies and ADCC against HIV-1-infected cells in vitro These results show there is a lag between viral recrudescence and the boosting of ADCC antibodies, which has implications for strategies towards eliminating latently infected cells...

  2. High proportions of regulatory B and T cells are associated with decreased cellular responses to pH1N1 influenza vaccine in HIV-infected children and youth (IMPAACT P1088).

    Science.gov (United States)

    Weinberg, Adriana; Muresan, Petronella; Fenton, Terence; Richardson, Kelly; Dominguez, Teresa; Bloom, Anthony; Petzold, Elizabeth; Anthony, Patricia; Cunningham, Coleen K; Spector, Stephen A; Nachman, Sharon; Siberry, George K; Handelsman, Edward; Flynn, Patricia M

    2013-05-01

    HIV-infected individuals have poor responses to inactivated influenza vaccines. To evaluate the potential role of regulatory T (Treg) and B cells (Breg), we analyzed their correlation with humoral and cell-mediated immune (CMI) responses to pandemic influenza (pH1N1) monovalent vaccine in HIV-infected children and youth. Seventy-four HIV-infected, 4- to 25-y old participants in a 2-dose pH1N1 vaccine study had circulating and pH1N1-stimulated Treg and Breg measured by flow cytometry at baseline, post-dose 1 and post-dose 2. Concomitantly, CMI was measured by ELISPOT and flow cytometry; and antibodies by hemagglutination inhibition (HAI). At baseline, most of the participants had pH1N1-specific IFNγ ELISPOT responses, whose magnitude positively correlated with the baseline pH1N1, but not with seasonal H1N1 HAI titers. pH1N1-specific IFNγ ELISPOT responses did not change post-dose 1 and significantly decreased post-dose 2. In contrast, circulating CD4+CD25+% and CD4+FOXP3+% Treg increased after vaccination. The decrease in IFNγ ELISPOT results was marginally associated with higher pH1N1-specific CD19+FOXP3+ and CD4+TGFβ+% Breg and Treg, respectively. In contrast, increases in HAI titers post-dose 1 were associated with significantly higher circulating CD19+CD25+% post-dose 1, whereas increases in IFNγ ELISPOT results post-dose 1 were associated with higher circulating CD4+/C8+CD25+FOXP3+%. In conclusion, in HIV-infected children and youth, influenza-specific Treg and Breg may contribute to poor responses to vaccination. However, robust humoral and CMI responses to vaccination may result in increased circulating Treg and/or Breg, establishing a feed-back mechanism.

  3. The Economic and Epidemiological Impact of Focusing Voluntary Medical Male Circumcision for HIV Prevention on Specific Age Groups and Regions in Tanzania

    Science.gov (United States)

    2016-01-01

    Background Since its launch in 2010, the Tanzania National Voluntary Medical Male Circumcision (VMMC) Program has focused efforts on males ages 10–34 in 11 priority regions. Implementers have noted that over 70% of VMMC clients are between the ages of 10 and 19, raising questions about whether additional efforts would be required to recruit men age 20 and above. This analysis uses mathematical modeling to examine the economic and epidemiological consequences of scaling up VMMC among specific age groups and priority regions in Tanzania. Methods and Findings Analyses were conducted using the Decision Makers’ Program Planning Tool Version 2.0 (DMPPT 2.0), a compartmental model implemented in Microsoft Excel 2010. The model was populated with population, mortality, and HIV incidence and prevalence projections from external sources, including outputs from Spectrum/AIDS Impact Module (AIM). A separate DMPPT 2.0 model was created for each of the 11 priority regions. Tanzania can achieve the most immediate impact on HIV incidence by circumcising males ages 20–34. This strategy would also require the fewest VMMCs for each HIV infection averted. Circumcising men ages 10–24 will have the greatest impact on HIV incidence over a 15-year period. The most cost-effective approach (lowest cost per HIV infection averted) targets men ages 15–34. The model shows the VMMC program is cost saving in all 11 priority regions. VMMC program cost-effectiveness varies across regions due to differences in projected HIV incidence, with the most cost-effective programs in Njombe and Iringa. Conclusions The DMPPT 2.0 results reinforce Tanzania’s current VMMC strategy, providing newfound confidence in investing in circumcising adolescents. Tanzanian policy makers and program implementers will continue to focus scale-up of VMMC on men ages 10–34 years, seeking to maximize program impact and cost-effectiveness while acknowledging trends in demand among the younger and older age groups

  4. The study of non-fouling and non-specific cellular binding on functionalized surface for mammalian cell identification and manipulation

    Science.gov (United States)

    Zainudin, Nor Syuhada; Hambali, Nor Azura Malini Ahmad; Wahid, Mohamad Halim Abd; Retnasamy, Vithyacharan; Shahimin, Mukhzeer Mohamad

    2017-04-01

    Surface functionalization has emerged as a powerful tool for mapping limitless surface-cell membrane interaction in diverse biomolecular applications. Inhibition of non-specific biomolecular and cellular adhesion to solid surfaces is critical in improving the performance of some biomedical devices, particularly for in vitro bioassays. Some factors have to be paid particular attention in determining the right surface modification which are the types of surface, the methods and chemical solution that being used during the experimentation and also tools for analyzing the results. Improved surface functionalization technologies that provide better non-fouling performance in conjunction with specific attachment chemistries are sought for these applications. Hence, this paper serves as a review for multiple surface treatment methods including PEG grafting, adsorptive chemistries, self-assembled monolayers (SAMs) and plasma treatments.

  5. Cellular and molecular characteristics of transformed T cells from an antigen-specific T-cell line

    DEFF Research Database (Denmark)

    Wegener, A M; Holm, B; Geisler, C

    1990-01-01

    the transformation event was poly-, oligo-, or monoclonal. The results indicate that the T lymphoma has no chromosome abnormalities, contains no tumour-inducing virus, can induce clone-specific immunity, and is oligoclonal with respect to TcR V alpha and V beta expression. The nature of the transformation event...... and clinical application of vaccination against T lymphomas is discussed. In addition, the expressed TcR V alpha and V beta repertoire of Con A T blasts was apparently not affected by the Igh-l or the MHC haplotype, as investigated in Igh-l and MHC congeneic C57Bl mice....

  6. Ontogeny of recognition specificity and functionality for the broadly neutralizing anti-HIV antibody 4E10.

    Directory of Open Access Journals (Sweden)

    Kathryn A K Finton

    2014-09-01

    Full Text Available The process of antibody ontogeny typically improves affinity, on-rate, and thermostability, narrows polyspecificity, and rigidifies the combining site to the conformer optimal for binding from the broader ensemble accessible to the precursor. However, many broadly-neutralizing anti-HIV antibodies incorporate unusual structural elements and recognition specificities or properties that often lead to autoreactivity. The ontogeny of 4E10, an autoreactive antibody with unexpected combining site flexibility, was delineated through structural and biophysical comparisons of the mature antibody with multiple potential precursors. 4E10 gained affinity primarily by off-rate enhancement through a small number of mutations to a highly conserved recognition surface. Controverting the conventional paradigm, the combining site gained flexibility and autoreactivity during ontogeny, while losing thermostability, though polyspecificity was unaffected. Details of the recognition mechanism, including inferred global effects due to 4E10 binding, suggest that neutralization by 4E10 may involve mechanisms beyond simply binding, also requiring the ability of the antibody to induce conformational changes distant from its binding site. 4E10 is, therefore, unlikely to be re-elicited by conventional vaccination strategies.

  7. Herpes Simplex Virus-2 Glycoprotein Interaction with HVEM Influences Virus-Specific Recall Cellular Responses at the Mucosa

    Directory of Open Access Journals (Sweden)

    Sarah J. Kopp

    2012-01-01

    Full Text Available Infection of susceptible cells by herpes simplex virus (HSV requires the interaction of the HSV gD glycoprotein with one of two principal entry receptors, herpes virus entry mediator (HVEM or nectins. HVEM naturally functions in immune signaling, and the gD-HVEM interaction alters innate signaling early after mucosal infection. We investigated whether the gD-HVEM interaction during priming changes lymphocyte recall responses in the murine intravaginal model. Mice were primed with attenuated HSV-2 expressing wild-type gD or mutant gD unable to engage HVEM and challenged 32 days later with virulent HSV-2 expressing wild-type gD. HSV-specific CD8+ T cells were decreased at the genital mucosa during the recall response after priming with virus unable to engage HVEM but did not differ in draining lymph nodes. CD4+ T cells, which are critical for entry of HSV-specific CD8+ T cells into mucosa in acute infection, did not differ between the two groups in either tissue. An inverse association between Foxp3+ CD4+ regulatory T cells and CD8+ infiltration into the mucosa was not statistically significant. CXCR3 surface expression was not significantly different among different lymphocyte subsets. We conclude that engagement of HVEM during the acute phase of HSV infection influences the antiviral CD8+ recall response by an unexplained mechanism.

  8. Cord blood Streptococcus pneumoniae-specific cellular immune responses predict early pneumococcal carriage in high-risk infants in Papua New Guinea.

    Science.gov (United States)

    Francis, J P; Richmond, P C; Strickland, D; Prescott, S L; Pomat, W S; Michael, A; Nadal-Sims, M A; Edwards-Devitt, C J; Holt, P G; Lehmann, D; van den Biggelaar, A H J

    2017-03-01

    In areas where Streptococcus pneumoniae is highly endemic, infants experience very early pneumococcal colonization of the upper respiratory tract, with carriage often persisting into adulthood. We aimed to explore whether newborns in high-risk areas have pre-existing pneumococcal-specific cellular immune responses that may affect early pneumococcal acquisition. Cord blood mononuclear cells (CBMC) of 84 Papua New Guinean (PNG; high endemic) and 33 Australian (AUS; low endemic) newborns were stimulated in vitro with detoxified pneumolysin (dPly) or pneumococcal surface protein A (PspA; families 1 and 2) and compared for cytokine responses. Within the PNG cohort, associations between CBMC dPly and PspA-induced responses and pneumococcal colonization within the first month of life were studied. Significantly higher PspA-specific interferon (IFN)-γ, tumour necrosis factor (TNF)-α, interleukin (IL)-5, IL-6, IL-10 and IL-13 responses, and lower dPly-IL-6 responses were produced in CBMC cultures of PNG compared to AUS newborns. Higher CBMC PspA-IL-5 and PspA-IL-13 responses correlated with a higher proportion of cord CD4 T cells, and higher dPly-IL-6 responses with a higher frequency of cord antigen-presenting cells. In the PNG cohort, higher PspA-specific IL-5 and IL-6 CBMC responses were associated independently and significantly with increased risk of earlier pneumococcal colonization, while a significant protective effect was found for higher PspA-IL-10 CBMC responses. Pneumococcus-specific cellular immune responses differ between children born in pneumococcal high versus low endemic settings, which may contribute to the higher risk of infants in high endemic settings for early pneumococcal colonization, and hence disease.

  9. PD-1 Expression and Cytokine Secretion Profiles of Mycobacterium tuberculosis-Specific CD4+ T-Cell Subsets; Potential Correlates of Containment in HIV-TB Co-Infection.

    Directory of Open Access Journals (Sweden)

    Katrina M Pollock

    Full Text Available HIV co-infection is an important risk factor for tuberculosis (TB providing a powerful model in which to dissect out defective, protective and dysfunctional Mycobacterium tuberculosis (MTB-specific immune responses. To identify the changes induced by HIV co-infection we compared MTB-specific CD4+ responses in subjects with active TB and latent TB infection (LTBI, with and without HIV co-infection. CD4+ T-cell subsets producing interferon-gamma (IFN-γ, interleukin-2 (IL-2 and tumour necrosis factor-alpha (TNF-α and expressing CD279 (PD-1 were measured using polychromatic flow-cytometry. HIV-TB co-infection was consistently and independently associated with a reduced frequency of CD4+ IFN-γ and IL-2-dual secreting T-cells and the proportion correlated inversely with HIV viral load (VL. The impact of HIV co-infection on this key MTB-specific T-cell subset identifies them as a potential correlate of mycobacterial immune containment. The percentage of MTB-specific IFN-γ-secreting T-cell subsets that expressed PD-1 was increased in active TB with HIV co-infection and correlated with VL. This identifies a novel correlate of dysregulated immunity to MTB, which may in part explain the paucity of inflammatory response in the face of mycobacterial dissemination that characterizes active TB with HIV co-infection.

  10. PD-1 Expression and Cytokine Secretion Profiles of Mycobacterium tuberculosis-Specific CD4+ T-Cell Subsets; Potential Correlates of Containment in HIV-TB Co-Infection.

    Science.gov (United States)

    Pollock, Katrina M; Montamat-Sicotte, Damien J; Grass, Lisa; Cooke, Graham S; Kapembwa, Moses S; Kon, Onn M; Sampson, Robert D; Taylor, Graham P; Lalvani, Ajit

    2016-01-01

    HIV co-infection is an important risk factor for tuberculosis (TB) providing a powerful model in which to dissect out defective, protective and dysfunctional Mycobacterium tuberculosis (MTB)-specific immune responses. To identify the changes induced by HIV co-infection we compared MTB-specific CD4+ responses in subjects with active TB and latent TB infection (LTBI), with and without HIV co-infection. CD4+ T-cell subsets producing interferon-gamma (IFN-γ), interleukin-2 (IL-2) and tumour necrosis factor-alpha (TNF-α) and expressing CD279 (PD-1) were measured using polychromatic flow-cytometry. HIV-TB co-infection was consistently and independently associated with a reduced frequency of CD4+ IFN-γ and IL-2-dual secreting T-cells and the proportion correlated inversely with HIV viral load (VL). The impact of HIV co-infection on this key MTB-specific T-cell subset identifies them as a potential correlate of mycobacterial immune containment. The percentage of MTB-specific IFN-γ-secreting T-cell subsets that expressed PD-1 was increased in active TB with HIV co-infection and correlated with VL. This identifies a novel correlate of dysregulated immunity to MTB, which may in part explain the paucity of inflammatory response in the face of mycobacterial dissemination that characterizes active TB with HIV co-infection.

  11. Cellular adhesion responses to the heparin-binding (HepII) domain of fibronectin require heparan sulfate with specific properties

    DEFF Research Database (Denmark)

    Mahalingam, Yashithra; Gallagher, John T; Couchman, John R

    2006-01-01

    Cell surface heparan sulfate (HS) proteoglycans are required in development and postnatal repair. Important classes of ligands for HS include growth factors and extracellular matrix macromolecules. For example, the focal adhesion component syndecan-4 interacts with the III(12-14) region of fibron......Cell surface heparan sulfate (HS) proteoglycans are required in development and postnatal repair. Important classes of ligands for HS include growth factors and extracellular matrix macromolecules. For example, the focal adhesion component syndecan-4 interacts with the III(12-14) region...... trap mutation in one of the two major glucosaminoglycan polymerases (EXT1). Several separate, specific properties of cell surface HS are therefore required in cell adhesion responses to the fibronectin HepII domain....

  12. [Should there be a specific management for HIV infected-immigrants in France?].

    Science.gov (United States)

    Méchali, D; Bouchaud, O

    2008-08-01

    Immigrants living in France account for one third of new cases of infection and are a target population for prevention. Care givers should adapt their management practice, taking into account this population's specificities which are not restricted to cultural differences but include major socioeconomic factors. In addition to training on alien rights and basic sociocultural knowledge, care-givers (especially clinicians) must spend more time with the patient (especially at the beginning of the relationship) and accept sharing the "medical power" with other people with a better knowledge of other aspects of the patients' life in addition to the medical one. As in other chronic diseases, mediation is one of the available tools with evident benefits for any patient. Assuming compliance is the same for migrants as for other patients, using this mediation will warrant therapeutic success.

  13. Organ-specific rates of cellular respiration in developing sunflower seedlings and their bearing on metabolic scaling theory.

    Science.gov (United States)

    Kutschera, Ulrich; Niklas, Karl J

    2012-10-01

    Fifty years ago Max Kleiber described what has become known as the "mouse-to-elephant" curve, i.e., a log-log plot of basal metabolic rate versus body mass. From these data, "Kleiber's 3/4 law" was deduced, which states that metabolic activity scales as the three fourths-power of body mass. However, for reasons unknown so far, no such "universal scaling law" has been discovered for land plants (embryophytes). Here, we report that the metabolic rates of four different organs (cotyledons, cotyledonary hook, hypocotyl, and roots) of developing sunflower (Helianthus annuus L.) seedlings grown in darkness (skotomorphogenesis) and in white light (photomorphogenesis) differ by a factor of 2 to 5 and are largely independent of light treatment. The organ-specific respiration rate (oxygen uptake per minute per gram of fresh mass) of the apical hook, which is composed of cells with densely packaged cytoplasm, is much higher than that of the hypocotyl, an organ that contains vacuolated cells. Data for cell length, cell density, and DNA content reveal that (1) hook opening in white light is caused by a stimulation of cell elongation on the inside of the curved organ, (2) respiration, cell density and DNA content are much higher in the hook than in the stem, and (3) organ-specific respiration rates and the DNA contents of tissues are statistically correlated. We conclude that, due to the heterogeneity of the plant body caused by the vacuolization of the cells, Kleiber's law, which was deduced using mammals as a model system, cannot be applied to embryophytes. In plants, this rule may reflect scaling phenomena at the level of the metabolically active protoplasmic contents of the cells.

  14. Role of SEREX-defined immunogenic wild-type cellular molecules in the development of tumor-specific immunity.

    Science.gov (United States)

    Nishikawa, H; Tanida, K; Ikeda, H; Sakakura, M; Miyahara, Y; Aota, T; Mukai, K; Watanabe, M; Kuribayashi, K; Old, L J; Shiku, H

    2001-12-04

    Recognition of altered self-antigens in tumor cells by lymphocytes forms the basis for antitumor immune responses. The effector cells in most experimental tumor systems are CD8(+) T cells that recognize MHC class I binding peptides derived from molecules with altered expression in tumor cells. Although the need for CD4(+) helper T cells in regulating CD8(+) T cells has been documented, their target epitopes and functional impact in antitumor responses remain unclear. We examined whether broadly expressed wild-type molecules in murine tumor cells eliciting humoral immunity contributed to the generation of CD8(+) T cells and protective antitumor immune responses to unrelated tumor-specific antigens [mutated ERK2 (mERK2) and c-erbB2/HER/neu (HER2)]. The immunogenic wild-type molecules, presumably dependent on recognition by CD4(+) helper T cells, were defined by serological analysis of recombinant cDNA expression libraries (SEREX) using tumor-derived lambda phage libraries screened with IgG antibodies of hosts bearing transplanted 3-methylchoranthrene-induced tumors. Coimmunization of mice with plasmids encoding SEREX-defined murine wild-type molecules and mERK2 or HER2 led to a profound increase in CD8(+) T cells specific for mERK2 or HER2 peptides. This heightened response depended on CD4(+) T cells and copresentation of SEREX-defined molecules and CD8(+) T cell epitopes. In tumor protection assays, immunization with SEREX-defined wild-type molecules and mERK2 resulted in an inhibition of pulmonary metastasis, which was not achieved by immunization with mERK2 alone.

  15. Toward a cure for HIV--Seeking effective therapeutic vaccine strategies.

    Science.gov (United States)

    Autran, Brigitte

    2015-12-01

    This review article focuses on the rationale and evaluation of therapeutic vaccines against HIV. This strategy has been developed in order to restore or restimulate HIV-specific immunity in patients treated with antiretroviral therapies. Despite the lack of good candidate vaccines against HIV, two objectives have been targeted during the past 15 years. Therapeutic immunization was first proposed to help control virus relapses during treatment interruptions. More recently, the concept of therapeutic immunization has been boosted by efforts to reach HIV remission or cure, in combination to HIV reactivating agents, to help purge HIV reservoirs in a "shock and kill" strategy. This review analyses the rationales for these strategies and the results of the most widely therapeutic vaccines designed to generate T-cell immunity, i.e. recombinant viral vectors and dendritic cell-based strategies, while extremely few strategies targeted HIV-specific Abs. Only marginal control of HIV was obtained with cellular-based strategies, suggesting that approaches targeting or using broadly neutralizing Abs, should be of benefit for future efforts of therapeutic immunization against HIV in the quest toward a cure for HIV.

  16. An inducible cell-cell fusion system with integrated ability to measure the efficiency and specificity of HIV-1 entry inhibitors.

    Directory of Open Access Journals (Sweden)

    Alon Herschhorn

    Full Text Available HIV-1 envelope glycoproteins (Envs mediate virus entry by fusing the viral and target cell membranes, a multi-step process that represents an attractive target for inhibition. Entry inhibitors with broad-range activity against diverse isolates of HIV-1 may be extremely useful as lead compounds for the development of therapies or prophylactic microbicides. To facilitate the identification of such inhibitors, we have constructed a cell-cell fusion system capable of simultaneously monitoring inhibition efficiency and specificity. In this system, effector cells stably express a tetracycline-controlled transactivator (tTA that enables tightly inducible expression of both HIV-1 Env and the Renilla luciferase (R-Luc reporter protein. Target cells express the HIV-1 receptors, CD4 and CCR5, and carry the firefly luciferase (F-Luc reporter gene under the control of a tTA-responsive promoter. Thus, Env-mediated fusion of these two cell types allows the tTA to diffuse to the target cell and activate the expression of the F-Luc protein. The efficiency with which an inhibitor blocks cell-cell fusion is measured by a decrease in the F-Luc activity, while the specificity of the inhibitor is evaluated by its effect on the R-Luc activity. The system exhibited a high dynamic range and high Z'-factor values. The assay was validated with a reference panel of inhibitors that target different steps in HIV-1 entry, yielding inhibitory concentrations comparable to published virus inhibition data. Our system is suitable for large-scale screening of chemical libraries and can also be used for detailed characterization of inhibitory and cytotoxic properties of known entry inhibitors.

  17. HIV-1 vaccine-specific responses induced by Listeria vector vaccines are maintained in mice subsequently infected with a model helminth parasite, Schistosoma mansoni.

    Science.gov (United States)

    Shollenberger, Lisa M; Bui, Cac T; Paterson, Yvonne; Nyhoff, Lindsay; Harn, Donald A

    2013-11-19

    In areas co-endemic for helminth parasites and HIV/AIDS, infants are often administered vaccines prior to infection with immune modulatory helminth parasites. Systemic Th2 biasing and immune suppression caused by helminth infection reduces cell-mediated responses to vaccines such as tetanus toxoid and BCG. Therefore, we asked if infection with helminthes post-vaccination, alters already established vaccine induced immune responses. In our model, mice are vaccinated against HIV-1 Gag using a Listeria vaccine vector (Lm-Gag) in a prime-boost manner, then infected with the human helminth parasite Schistosoma mansoni. This allows us to determine if established vaccine responses are maintained or altered after helminth infection. Our second objective asked if helminth infection post-vaccination alters the recipient's ability to respond to a second boost. Here we compared responses between uninfected mice, schistosome infected mice, and infected mice that were given an anthelminthic, which occurred coincident with the boost or four weeks prior, as well as comparing to un-boosted mice. We report that HIV-1 vaccine-specific responses generated by Listeria vector HIV-1 vaccines are maintained following subsequent chronic schistosome infection, providing further evidence that Listeria vector vaccines induce potent vaccine-specific responses that can withstand helminth infection. We also were able to demonstrate that administration of a second Listeria boost, which markedly enhanced the immune response, was minimally impacted by schistosome infection, or anthelminthic therapy. Surprisingly, we also observed enhanced antibody responses to HIV Gag in vaccinated mice subsequently infected with schistosomes.

  18. Specific photosynthetic rate enhancement by cyanobacteria coated onto paper enables engineering of highly reactive cellular biocomposite "leaves".

    Science.gov (United States)

    Bernal, Oscar I; Mooney, Charles B; Flickinger, Michael C

    2014-10-01

    We describe a latex wet coalescence extrusive coating method that produces up to 10-fold specific photosynthetic rate enhancements by nitrate-limited non-growing cyanobacteria deposited onto paper, hydrated and placed in the gas-phase of small tube photobioreactors. These plant leaf-like biocomposites were used to study the tolerance of cyanobacteria strains to illumination and temperature using a solar simulator. We report sustained CO2 absorption and O2 production for 500 h by hydrated gas-phase paper coatings of non-growing Synechococcus PCC7002, Synechocystis PCC6803, Synechocystis PCC6308, and Anabaena PCC7120. Nitrate-starved cyanobacteria immobilized on the paper surface by the latex binder did not grow out of the coatings into the bulk liquid. The average CO2 consumption rate in Synechococcus coatings is 5.67 mmol m(-2)  h(-1) which is remarkably close to the rate reported in the literature for Arabidopsis thaliana leaves under similar experimental conditions (18 mmol m(-2)  h(-1) ). We observed average ratios of oxygen production to carbon dioxide consumption (photosynthetic quotient, PQ) between 1.3 and 1.4, which may indicate a strong dependence on nitrate assimilation during growth and was used to develop a non-growth media formulation for intrinsic kinetics studies. Photosynthetic intensification factors (PIF) (O2 production by nitrate-limited cyanobacteria in latex coatings/O2 produced by nitrate-limited cell suspensions) in cyanobacteria biocomposites prepared from wet cell pellets concentrated 100- to 300-fold show 7-10 times higher specific reactivity compared to cells in suspension under identical nitrate-limited non-growth conditions. This is the first report of changes of cyanobacteria tolerance to temperature and light intensities after deposition as a thin coating on a porous matrix, which has important implications for gas-phase photobioreactor design using porous composite materials. Cryo-fracture SEM and confocal microscopy

  19. GapmeR cellular internalization by macropinocytosis induces sequence-specific gene silencing in human primary T-cells

    Science.gov (United States)

    Fazil, Mobashar Hussain Urf Turabe; Ong, Seow Theng; Chalasani, Madhavi Latha Somaraju; Low, Jian Hui; Kizhakeyil, Atish; Mamidi, Akshay; Lim, Carey Fang Hui; Wright, Graham D.; Lakshminarayanan, Rajamani; Kelleher, Dermot; Verma, Navin Kumar

    2016-01-01

    Post-transcriptional gene silencing holds great promise in discovery research for addressing intricate biological questions and as therapeutics. While various gene silencing approaches, such as siRNA and CRISPR-Cas9 techniques, are available, these cannot be effectively applied to “hard-to-transfect” primary T-lymphocytes. The locked nucleic acid-conjugated chimeric antisense oligonucleotide, called “GapmeR”, is an emerging new class of gene silencing molecule. Here, we show that GapmeR internalizes into human primary T-cells through macropinocytosis. Internalized GapmeR molecules can associate with SNX5-positive macropinosomes in T-cells, as detected by super-resolution microscopy. Utilizing the intrinsic self-internalizing capability of GapmeR, we demonstrate significant and specific depletion (>70%) of the expression of 5 different endogenous proteins with varying molecular weights (18 kDa Stathmin, 80 kDa PKCε, 180 kDa CD11a, 220 kDa Talin1 and 450 kDa CG-NAP/AKAP450) in human primary and cultured T-cells. Further functional analysis confirms CG-NAP and Stathmin as regulators of T-cell motility. Thus, in addition to screening, identifying or verifying critical roles of various proteins in T-cell functioning, this study provides novel opportunities to silence individual or multiple genes in a subset of purified human primary T-cells that would be exploited as future therapeutics. PMID:27883055

  20. Specific amplification of gene encoding N-terminal region of catalase-peroxidase protein (KatG-N) for diagnosis of disseminated MAC disease in HIV patients.

    Science.gov (United States)

    Latawa, Romica; Singh, Krishna Kumar; Wanchu, Ajay; Sethi, Sunil; Sharma, Kusum; Sharma, Aman; Laal, Suman; Verma, Indu

    2014-10-01

    Disseminated Mycobacterium avium-intracellulare complex (MAC) infection is considered as severe complication of advanced HIV/AIDS disease. Currently available various laboratory investigations have not only limited ability to discriminate between MAC infection and tuberculosis but are also laborious and time consuming. The aim of this study was, therefore, to design a molecular-based strategy for specific detection of MAC and its differentiation from Mycobacterium tuberculosis (M. tb) isolated from the blood specimens of HIV patients. A simple PCR was developed based on the amplification of 120-bp katG-N gene corresponding to the first 40 amino acids of N-terminal catalase-peroxidase (KatG) protein of Mycobacterium avium that shows only ~13% sequence homology by clustal W alignment to N-terminal region of M. tb KatG protein. This assay allowed the accurate and rapid detection of MAC bacteremia, distinguishing it from M. tb in a single PCR reaction without any need for sequencing or hybridization protocol to be performed thereafter. This study produced enough evidence that a significant proportion of Indian HIV patients have disseminated MAC bacteremia, suggesting the utility of M. avium katG-N gene PCR for early detection of MAC disease in HIV patients. Copyright © 2014 Elsevier Inc. All rights reserved.

  1. Specific protein profile in cerebrospinal fluid from HIV-1-positive cART-treated patients affected by neurological disorders.

    Science.gov (United States)

    Zanin, Valentina; Delbue, Serena; Marcuzzi, Annalisa; Tavazzi, Eleonora; Del Savio, Rossella; Crovella, Sergio; Marchioni, Enrico; Ferrante, Pasquale; Comar, Manola

    2012-10-01

    Cytokines/chemokines are involved in the immune response of infections, including HIV-1. We defined the profile of 48 cytokines/chemokines in cerebrospinal fluid from 18 cART patients with chronic HIV-1 infection by Luminex technology. Nine patients were affected with leukoencephalopathies: five with John Cunningham virus (JCV) + progressive multifocal leukoencephalopathy (PML) and four with JCV-not determined leukoencephalopathy (NDLE). In addition, nine HIV-1-positive patients with no neurological signs (NND) and five HIV-1-negative patients affected with acute disseminated encephalomyelitis (ADEM) were enrolled. Ten cytokines (IL-15, IL-3, IL-16, IL-18, CTACK, GRO1, SCF, MCP-1, MIF, SDF) were highly expressed in HIV-1-positive patients while IL-1Ra and IL-17 were present at a lower level. In addition, the levels of IL-17, IL-9, FGF-basic, MIP-1β, and MCP-1 were significantly higher (p < 0.05) in patients with neurological diseases (PML, NDLE, ADEM) with respect to NND. Focusing the attention to the cytokine profile in JCV + PML patients with respect to JCV-NDLE patients, only TNF-β was significantly downregulated (p < 0.05) in JCV + PML patients. This pilot study emphasized the role of immunoregulation in HIV-1-related neurological disorders during cART treatment.

  2. Immunotherapy with an HIV-DNA Vaccine in Children and Adults

    Directory of Open Access Journals (Sweden)

    Paolo Palma

    2014-07-01

    Full Text Available Therapeutic HIV immunization is intended to induce new HIV-specific cellular immune responses and to reduce viral load, possibly permitting extended periods without antiretroviral drugs. A multigene, multi-subtype A, B, C HIV-DNA vaccine (HIVIS has been used in clinical trials in both children and adults with the aim of improving and broadening the infected individuals’ immune responses. Despite the different country locations, different regimens and the necessary variations in assays performed, this is, to our knowledge, the first attempt to compare children’s and adults’ responses to a particular HIV vaccine. Ten vertically HIV-infected children aged 4–16 years were immunized during antiretroviral therapy (ART. Another ten children were blindly recruited as controls. Both groups continued their antiretroviral treatment during and after vaccinations. Twelve chronically HIV-infected adults were vaccinated, followed by repeated structured therapy interruptions (STI of their antiretroviral treatment. The adult group included four controls, receiving placebo vaccinations. The HIV-DNA vaccine was generally well tolerated, and no serious adverse events were registered in any group. In the HIV-infected children, an increased specific immune response to Gag and RT proteins was detected by antigen-specific lymphoproliferation. Moreover, the frequency of HIV-specific CD8+ T-cell lymphocytes releasing perforin was significantly higher in the vaccinees than the controls. In the HIV-infected adults, increased CD8+ T-cell responses to Gag, RT and viral protease peptides were detected. No augmentation of HIV-specific lymphoproliferative responses were detected in adults after vaccination. In conclusion, the HIV-DNA vaccine can elicit new HIV-specific cellular immune responses, particularly to Gag antigens, in both HIV-infected children and adults. Vaccinated children mounted transient new HIV-specific immune responses, including both CD4+ T

  3. Engineered outer membrane vesicle is potent to elicit HPV16E7-specific cellular immunity in a mouse model of TC-1 graft tumor.

    Science.gov (United States)

    Wang, Shijie; Huang, Weiwei; Li, Kui; Yao, Yufeng; Yang, Xu; Bai, Hongmei; Sun, Wenjia; Liu, Cunbao; Ma, Yanbing

    2017-01-01

    Currently, therapeutic tumor vaccines under development generally lack significant effects in human clinical trials. Exploring a powerful antigen delivery system is a potential approach to improve vaccine efficacy. We sought to explore engineered bacterial outer membrane vesicles (OMVs) as a new vaccine carrier for efficiently delivering tumor antigens and provoking robust antitumor immune responses. First, the tumoral antigen human papillomavirus type 16 early protein E7 (HPV16E7) was presented on Escherichia coli-derived OMVs by genetic engineering methods, acquiring the recombinant OMV vaccine. Second, the ability of recombinant OMVs delivering their components and the model antigen green fluorescent protein to antigen-presenting cells was investigated in the macrophage Raw264.7 cells and in bone marrow-derived dendritic cells in vitro. Third, it was evaluated in TC-1 graft tumor model in mice that the recombinant OMVs displaying HPV16E7 stimulated specific cellular immune response and intervened the growth of established tumor. E. coli DH5α-derived OMVs could be taken up rapidly by dendritic cells, for which vesicle structure has been proven to be important. OMVs significantly stimulated the expression of dendritic cellmaturation markers CD80, CD86, CD83 and CD40. The HPV16E7 was successfully embedded in engineered OMVs through gene recombinant techniques. Subcutaneous immunization with the engineered OMVs induced E7 antigen-specific cellular immune responses, as shown by the increased numbers of interferon-gamma-expressing splenocytes by enzyme-linked immunospot assay and interferon-gamma-expressing CD4(+) and CD8(+) cells by flow cytometry analyses. Furthermore, the growth of grafted TC-1 tumors in mice was significantly suppressed by therapeutic vaccination. The recombinant E7 proteins presented by OMVs were more potent than those mixed with wild-type OMVs or administered alone for inducing specific cellular immunity and suppressing tumor growth. The

  4. A Heterogeneous Cellular Automata Model with Age Structure for HIV Transmission%具有年龄结构的异质元胞自动机HIV传播模型

    Institute of Scientific and Technical Information of China (English)

    王仲君; 张莉丽

    2014-01-01

    年龄结构影响群体发病率,将群体年龄分为5个阶段,建立扩展的异质元胞自动机模型,研究艾滋病在高发区及普通地区的传播行为。模型中,元胞具有不同的年龄,传染强度依状态改变,结合邻域内个体间致病性接触行为建立邻域元胞影响力函数,改进状态更新规则。仿真结果发现,个体的致病性接触行为、人群密度、元胞影响半径对艾滋病的传播速度及群体感染率具有一定影响,而个体年龄结构则在一定程度上影响群体感染分布情况。%According to statistics , age structure has an effect on the incidence of AIDS .The group can be divided into five categories with different incubations based on different ages .An expanded heterogeneous cellular automata model was built and then HIV transmission in area of high and average infection rate were respectively simulated .In this model , the cellular has dif-ferent ages;the intensity of infection changes with cell state .The influence function of neighborhood considering of the pathogenic contact behavior between neighborhoods was built to improve the rule of status updates .The simulation shows that pathogenic con-tact behavior , crowd density , and radius of influence have certain influences on the spread of HIV transmission; and the age structure has a certain influence on the outbreak of AIDS .

  5. Mosaic vaccines elicit CD8+ T cell responses in monkeys that confer immune coverage of diverse HIV strains

    Energy Technology Data Exchange (ETDEWEB)

    Fischer, Will [Los Alamos National Laboratory; Korber, Bette [Los Alamos National Laboratory

    2009-01-01

    Creation of a successful HIV vaccine will require the development of a strategy to generate cellular immunity with sufficient cross-clade breadth to deal with the extreme genetic diversity of the virus. Polyvalent mosaic immunogens derived from in silica recombination of natural strains of HIV are designed to induce cellular immune responses that maximally cover the sequence diversity of circulating virus isolates. Immunization of rhesus monkeys with plasmid DNA and recombinant vaccinia virus vaccine constructs expressing either consensus immunogens or polyvalent mosaic immunogens elicited a CD4+ T lymphocyte-biased response with comparably broad epitope-specific total T lymphocyte specificities. However, immunization with the mosaic immunogens induced HIV-specific CD8+ T lymphocyte responses with markedly greater depth and breadth. Therefore, the use of polyvalent mosaic immunogens is a promising strategy for a global vaccine for HIV.

  6. Consensus HIV-1 FSU-A integrase gene variants electroporated into mice induce polyfunctional antigen-specific CD4+ and CD8+ T cells.

    Directory of Open Access Journals (Sweden)

    Olga Krotova

    Full Text Available Our objective is to create gene immunogens targeted against drug-resistant HIV-1, focusing on HIV-1 enzymes as critical components in viral replication and drug resistance. Consensus-based gene vaccines are specifically fit for variable pathogens such as HIV-1 and have many advantages over viral genes and their expression-optimized variants. With this in mind, we designed the consensus integrase (IN of the HIV-1 clade A strain predominant in the territory of the former Soviet Union and its inactivated derivative with and without mutations conferring resistance to elvitegravir. Humanized IN gene was synthesized; and inactivated derivatives (with 64D in the active site mutated to V with and without elvitegravir-resistance mutations were generated by site-mutagenesis. Activity tests of IN variants expressed in E coli showed the consensus IN to be active, while both D64V-variants were devoid of specific activities. IN genes cloned in the DNA-immunization vector pVax1 (pVaxIN plasmids were highly expressed in human and murine cell lines (>0.7 ng/cell. Injection of BALB/c mice with pVaxIN plasmids followed by electroporation generated potent IFN-γ and IL-2 responses registered in PBMC by day 15 and in splenocytes by day 23 after immunization. Multiparametric FACS demonstrated that CD8+ and CD4+ T cells of gene-immunized mice stimulated with IN-derived peptides secreted IFN-γ, IL-2, and TNF-α. The multi-cytokine responses of CD8+ and CD4+ T-cells correlated with the loss of in vivo activity of the luciferase reporter gene co-delivered with pVaxIN plasmids. This indicated the capacity of IN-specific CD4+ and CD8+ T-cells to clear IN/reporter co-expressing cells from the injection sites. Thus, the synthetic HIV-1 clade A integrase genes acted as potent immunogens generating polyfunctional Th1-type CD4+ and CD8+ T cells. Generation of such response is highly desirable for an effective HIV-1 vaccine as it offers a possibility to attack virus

  7. Saccharomyces cerevisiae Ngl3p is an active 3′–5′ exonuclease with a specificity towards poly-A RNA reminiscent of cellular deadenylases

    DEFF Research Database (Denmark)

    Feddersen, Ane; Dedic, Emil; Poulsen, Esben Guldahl

    2012-01-01

    –Endonuclease–Phosphatase (EEP) families, respectively. Ngl3p has been identified as a new member of the EEP family of exonucleases based on sequence homology, but its activity and biological roles are presently unknown. Here, we show using in vitro deadenylation assays on defined RNA species mimicking poly-A containing m......RNAs that yeast Ngl3p is a functional 3′–5′ exonuclease most active at slightly acidic conditions. We further show that the enzyme depends on divalent metal ions for activity and possesses specificity towards poly-A RNA similar to what has been observed for cellular deadenylases. The results suggest that Ngl3p...

  8. Evaluation of the efficacy of a therapeutic HIV vaccine by in vitro stimulation assay.

    Science.gov (United States)

    He, Xiaozhou; Wang, Wandi; Xu, Ke; Feng, Xia; Zeng, Yi

    2017-03-01

    A novel method for HIV vaccine efficacy evaluation was established and the experimental conditions optimized. This novel method was then applied to determine whether a recombinant adenovirus type 5 HIV therapeutic vaccine expressing Gag antigen (Ad5-HIVgag) could stimulate HIV-specific cellular responses in vitro. The results indicated that HIV-specific IFN-gama production lymphocytes were induced by the Ad5-HIVgag vaccine. Compared with other methods, this in vitro stimulation method is safe and time-efficient, and the result is more intuitive. It has the potential to be regarded as a supplement to other methods for evaluating the IFN-gamma production by PBMCs to HIV vaccination. Copyright © 2017 Elsevier Inc. All rights reserved.

  9. Chimeric antigen receptor engineered stem cells: a novel HIV therapy.

    Science.gov (United States)

    Zhen, Anjie; Carrillo, Mayra A; Kitchen, Scott G

    2017-03-01

    Despite the success of combination antiretroviral therapy (cART) for suppressing HIV and improving patients' quality of life, HIV persists in cART-treated patients and remains an incurable disease. Financial burdens and health consequences of lifelong cART treatment call for novel HIV therapies that result in a permanent cure. Cellular immunity is central in controlling HIV replication. However, HIV adopts numerous strategies to evade immune surveillance. Engineered immunity via genetic manipulation could offer a functional cure by generating cells that have enhanced antiviral activity and are resistant to HIV infection. Recently, encouraging reports from several human clinical trials using an anti-CD19 chimeric antigen receptor (CAR) modified T-cell therapy for treating B-cell malignancies have provided valuable insights and generated remarkable enthusiasm in engineered T-cell therapy. In this review, we discuss the development of HIV-specific chimeric antigen receptors and the use of stem cell based therapies to generate lifelong anti-HIV immunity.

  10. PIKA as an Adjuvant Enhances Specific Humoral and Cellular Immune Responses Following the Vaccination of Mice with HBsAg plus PIKA

    Institute of Scientific and Technical Information of China (English)

    Erxia Shen; Li Li; Lietao Li; Lianqiang Feng; Lin Lu; Ziliang Yao; Haixiang Lin; Changyou Wu

    2007-01-01

    An adjuvant is usually used to enhance the immune response induced by vaccines. The choice of adjuvant or immune enhancer determines the effectiveness of the immune response. Currently, aluminium (Alum, a generic term for salts of aluminium) is the only FDA-approved adjuvant. Alum predominantly induces the differentiation of Th2 cells and thus mediates an antibody immune response. Therefore, there is an urgent need for new adjuvants that enhance not only humoral but also cellular immune responses. In the present study, we demonstrates that PIKA (a stabilized dsRNA) as an adjuvant directly induces the activation and the proliferation of both B and NK cells in vitro. Injection of PIKA into mice results in the production of cytokines in vivo. In addition, the study demonstrates that PIKA promotes the maturation of bone marrow-derived dendritic cells (BMDCs) including up-regulation of the co-stimulatory molecules CD80, CD86 and CD40, and the induction of cytokines such as IL-12p70, IL-12p40 and IL-6. Importantly, after immunization of mice with HBsAg plus PIKA, the presence of PIKA enhances the titers of HBsAg-specific IgG and HBsAg-specific IFN-γ production. These results demonstrate that PIKA as an adjuvant can promote both humoral and cellular immune responses. These might have an implication in applying PIKA as an adjuvant to be used in the design and development of both therapeutic and preventive vaccines, and used in the clinical study.

  11. Retina-specific nuclear receptor: A potential regulator of cellular retinaldehyde-binding protein expressed in retinal pigment epithelium and Müller glial cells.

    Science.gov (United States)

    Chen, F; Figueroa, D J; Marmorstein, A D; Zhang, Q; Petrukhin, K; Caskey, C T; Austin, C P

    1999-12-21

    In an effort to identify nuclear receptors important in retinal disease, we screened a retina cDNA library for nuclear receptors. Here we describe the identification of a retina-specific nuclear receptor (RNR) from both human and mouse. Human RNR is a splice variant of the recently published photoreceptor cell-specific nuclear receptor [Kobayashi, M., Takezawa, S., Hara, K., Yu, R. T., Umesono, Y., Agata, K., Taniwaki, M., Yasuda, K. & Umesono, K. (1999) Proc. Natl. Acad. Sci. USA 96, 4814-4819] whereas the mouse RNR is a mouse ortholog. Northern blot and reverse transcription-PCR analyses of human mRNA samples demonstrate that RNR is expressed exclusively in the retina, with transcripts of approximately 7.5 kb, approximately 3.0 kb, and approximately 2.3 kb by Northern blot analysis. In situ hybridization with multiple probes on both primate and mouse eye sections demonstrates that RNR is expressed in the retinal pigment epithelium and in Müller glial cells. By using the Gal4 chimeric receptor/reporter cotransfection system, the ligand binding domain of RNR was found to repress transcriptional activity in the absence of exogenous ligand. Gel mobility shift assays revealed that RNR can interact with the promoter of the cellular retinaldehyde binding protein gene in the presence of retinoic acid receptor (RAR) and/or retinoid X receptor (RXR). These data raise the possibility that RNR acts to regulate the visual cycle through its interaction with cellular retinaldehyde binding protein and therefore may be a target for retinal diseases such as retinitis pigmentosa and age-related macular degeneration.

  12. Allele-specific real-time PCR testing for minor HIV-1 drug resistance mutations: assay preparation and application to reveal dynamic of mutations in vivo

    Institute of Scientific and Technical Information of China (English)

    GUO Dong-xing; LI Jing-yun; LI Han-ping; LI Lin; ZHUANG Dao-min; JIAO Li-yan; WANG Zheng; BAO Zuo-yi; LIU Si-yang; LIU Yong-jian

    2010-01-01

    Background It is very important for the clinical management to test for minor HIV-1 resistance mutations accurately and sensitively. The conventional genotypic assays of HIV drug resistance detection based on sequencing can only discriminate the mutations which present in more than 20%-30%. The aim of this study was to evaluate allele-specific real-time PCR (ASPCR) to detect the resistance-related mutations located at positions 103, 184 and 215.Methods We developed the allele-specific PCR assay, using the most common drug resistance mutations in Chinese AIDS patients, K103N, M184V/I, T215F/Y as a model system. The standards were constructed by cloning the wild-type and mutant DNA fragments into the T-vector. We designed specific primers to discriminate mutant templates in the real-time PCR using SYBR green as a fluorescence reporter. And then we evaluated the ASPCR assay and tested 140clinical samples using this method.Results The sensitivities of ASPCR assay were 0.04% for K103N, 0.30% for M1841, 0.40% for M184V, 0.03% for T215F and 0.02% for T215Y. The intra-assay and inter-assay coefficients of variation were less than 0.42. One hundred and forty plasma samples were tested by ASPCR and dynamic resistance curves of ten patients were obtained.Conclusions Drug resistance emerged half a year after the start of antiretroviral therapy. The mutation of T215Yemerged 1 to 1.5 years after starting treatment and then increased rapidly. The ASPCR assay we developed was a sensitive, accurate and rapid method to detect the minor HIV-1 variants and it can provide earlier and more drug-resistance information for HIV research and AIDS antiretroviral therapy.

  13. Priming immunization with DNA augments immunogenicity of recombinant adenoviral vectors for both HIV-1 specific antibody and T-cell responses.

    Directory of Open Access Journals (Sweden)

    Richard A Koup

    Full Text Available Induction of HIV-1-specific T-cell responses relevant to diverse subtypes is a major goal of HIV vaccine development. Prime-boost regimens using heterologous gene-based vaccine vectors have induced potent, polyfunctional T cell responses in preclinical studies.The first opportunity to evaluate the immunogenicity of DNA priming followed by recombinant adenovirus serotype 5 (rAd5 boosting was as open-label rollover trials in subjects who had been enrolled in prior studies of HIV-1 specific DNA vaccines. All subjects underwent apheresis before and after rAd5 boosting to characterize in depth the T cell and antibody response induced by the heterologous DNA/rAd5 prime-boost combination.rAd5 boosting was well-tolerated with no serious adverse events. Compared to DNA or rAd5 vaccine alone, sequential DNA/rAd5 administration induced 7-fold higher magnitude Env-biased HIV-1-specific CD8(+ T-cell responses and 100-fold greater antibody titers measured by ELISA. There was no significant neutralizing antibody activity against primary isolates. Vaccine-elicited CD4(+ and CD8(+ T-cells expressed multiple functions and were predominantly long-term (CD127(+ central or effector memory T cells and that persisted in blood for >6 months. Epitopes mapped in Gag and Env demonstrated partial cross-clade recognition.Heterologous prime-boost using vector-based gene delivery of vaccine antigens is a potent imm