CCR5 interaction with HIV-1 Env contributes to Env-induced depletion of CD4 T cells in vitro and in vivo

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.

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The Interplay of HIV-1 and Macrophages in Viral Persistence

Frontiers in Microbiology ◽

10.3389/fmicb.2021.646447 ◽

2021 ◽

Vol 12 ◽

Author(s):

Chynna M. Hendricks ◽

Thaissa Cordeiro ◽

Ana Paula Gomes ◽

Mario Stevenson

Keyword(s):

T Cells ◽

Cd4 T Cells ◽

Viral Persistence ◽

Vital Role ◽

Highly Active ◽

Antiretroviral Therapies ◽

Memory Cd4 T Cells ◽

Hiv 1

HIV-1 has evolved mechanisms to evade host cell immune responses and persist for lifelong infection. Latent cellular reservoirs are responsible for this persistence of HIV-1 despite the powerful effects of highly active antiretroviral therapies (HAART) to control circulating viral load. While cellular reservoirs have been extensively studied, much of these studies have focused on peripheral blood and resting memory CD4+ T cells containing latent HIV-1 provirus; however, efforts to eradicate cellular reservoirs have been stunted by reservoirs found in tissues compartments that are not easily accessible. These tissues contain resting memory CD4+ T cells and tissue resident macrophages, another latent cellular reservoir to HIV-1. Tissue resident macrophages have been associated with HIV-1 infection since the 1980s, and evidence has continued to grow regarding their role in HIV-1 persistence. Specific biological characteristics play a vital role as to why macrophages are latent cellular reservoirs for HIV-1, and in vitro and in vivo studies exhibit how macrophages contribute to viral persistence in individuals and animals on antiretroviral therapies. In this review, we characterize the role and evolutionary advantages of macrophage reservoirs to HIV-1 and their contribution to HIV-1 persistence. In acknowledging the interplay of HIV-1 and macrophages in the host, we identify reasons why current strategies are incapable of eliminating HIV-1 reservoirs and why efforts must focus on eradicating reservoirs to find a future functional cure.

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HIV-1 Vpr- and Reverse Transcription-Induced Apoptosis in Resting Peripheral Blood CD4 T Cells and Protection by Common Gamma-Chain Cytokines

Journal of Virology ◽

10.1128/jvi.01770-15 ◽

2015 ◽

Vol 90 (2) ◽

pp. 904-916 ◽

Cited By ~ 13

Author(s):

Benjamin Trinité ◽

Chi N. Chan ◽

Caroline S. Lee ◽

David N. Levy

Keyword(s):

T Cells ◽

Cell Death ◽

T Cell ◽

Reverse Transcription ◽

Peripheral Blood ◽

Cd4 T Cells ◽

Productive Infection ◽

Hiv 1

ABSTRACTHIV-1 infection leads to the progressive depletion of the CD4 T cell compartment by various known and unknown mechanisms.In vivo, HIV-1 infects both activated and resting CD4 T cells, butin vitro, in the absence of any stimuli, resting CD4 T cells from peripheral blood are resistant to infection. This resistance is generally attributed to an intracellular environment that does not efficiently support processes such as reverse transcription (RT), resulting in abortive infection. Here, we show thatin vitroHIV-1 infection of resting CD4 T cells induces substantial cell death, leading to abortive infection.In vivo, however, various microenvironmental stimuli in lymphoid and mucosal tissues provide support for HIV-1 replication. For example, common gamma-chain cytokines (CGCC), such as interleukin-7 (IL-7), render resting CD4 T cells permissible to HIV-1 infection without inducing T cell activation. Here, we find that CGCC primarily allow productive infection by preventing HIV-1 triggering of apoptosis, as evidenced by early release of cytochromecand caspase 3/7 activation. Cell death is triggered both by products of reverse transcription and by virion-borne Vpr protein, and CGCC block both mechanisms. When HIV-1 RT efficiency was enhanced by SIVmac239 Vpx protein, cell death was still observed, indicating that the speed of reverse transcription and the efficiency of its completion contributed little to HIV-1-induced cell death in this system. These results show that a major restriction on HIV-1 infection in resting CD4 T cells resides in the capacity of these cells to survive the early steps of HIV-1 infection.IMPORTANCEA major consequence of HIV-1 infection is the destruction of CD4 T cells. Here, we show that delivery of virion-associated Vpr protein and the process of reverse transcription are each sufficient to trigger apoptosis of resting CD4 T cells isolated from peripheral blood. While these 2 mechanisms have been previously described in various cell types, we show for the first time their concerted effect in inducing resting CD4 T cell depletion. Importantly, we found that cytokines such as IL-7 and IL-4, which are particularly active in sites of HIV-1 replication, protect resting CD4 T cells from these cytopathic effects and, primarily through this protection, rather than through enhancement of specific replicative steps, they promote productive infection. This study provides important new insights for the understanding of the early steps of HIV-1 infection and T cell depletion.

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Specific activation of HIV-1 from monocytic reservoir cells by bromodomain inhibitor in humanized mice in vivo

10.1101/375535 ◽

2018 ◽

Cited By ~ 1

Author(s):

Guangming Li ◽

Zheng Zhang ◽

Natalia Reszka-Blanco ◽

Feng Li ◽

Liqun Chi ◽

...

Keyword(s):

Gene Expression ◽

T Cells ◽

Cd4 T Cells ◽

Humanized Mice ◽

Viral Transcription ◽

Dependent Manner ◽

Monocytic Cells ◽

Hiv 1

ABSTRACTThe combination antiretroviral therapy (cART) effectively suppresses HIV-1 infection and enables HIV-infected individuals to live long productive lives. However, the persistence of HIV-1 reservoir cells with latent or low-replicating HIV-1 in patients under cART make HIV-1 infection an incurable disease. Recent studies have focused on the development of strategies such as epigenetic modulators to activate and purge these reservoirs. Bromodomain inhibitors (BETi) are epigenetic modulating compounds able to activate viral transcription in HIV-1 latency cell lines in a positive transcription elongation factor b (P-TEFb)-dependent manner. Little is known about the efficacy of activating HIV-1 reservoir cells under cART by BETi in vivo. In this study, we seek to test the potential of a BETi (I-BET151) in activating HIV-1 reservoir cells under effective cART in humanized mice in vivo. We discover that I-BET151 efficiently activates HIV-1 transcription in monocytic cells, but not in CD4+T cells, during suppressive cART in vivo. We further reveal that HIV-1 proviruses in monocytic cells are more sensitive to I-BET151 treatment than in T cells in vitro. Finally, we demonstrate that I-BET151-activated viral transcription in monocytic cells is dependent on both CDK2 and CDK9, whereas only CDK9 is involved in activation of HIV-1 by I-BET151 in T cells. Our findings indicate a role of myeloid cells in HIV-1 persistence, and highlights the limitation of measuring or targeting T cell reservoirs alone in terms of HIV-1 cure, as well as provides a potential strategy to reactivate monocytic reservoirs during cART.IMPORTANCEIt has been reported the low level of active P-TEFb critically contributes to the maintenance of HIV-1 latency or low-replication in HIV-1 reservoir cells under cART. Bromodomain inhibitors are used to activate HIV-1 replication in vitro but their effect on activation of the HIV-1 resevoirs with cART in vivo is not clear. We found that BETi (I-BET151) treatment reactivated HIV-1 gene expression in humanized mice during suppressive cART. Interestingly, I-BET151 preferentially reactivated HIV-1 gene expression in monocytic cells, but not in CD4 T cells. Furthermore, I-BET151 significantly increased HIV-1 transcription in monocytic cells, but not in latently infected CD4 T cells, via CDK2-dependent mechanisms. Our findings suggest that BETi can preferentially activate monocytic HIV-1 reservoir cells, and a combination of latency reversal agents targeting different cell types and pathways is needed to achieve reactivation of different HIV-1 reservoir cells during cART.

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In Vitro Priming Recapitulates In Vivo HIV-1 Specific T Cell Responses, Revealing Rapid Loss of Virus Reactive CD4+ T Cells in Acute HIV-1 Infection

PLoS ONE ◽

10.1371/journal.pone.0004256 ◽

2009 ◽

Vol 4 (1) ◽

pp. e4256 ◽

Cited By ~ 31

Author(s):

Rachel Lubong Sabado ◽

Daniel G. Kavanagh ◽

Daniel E. Kaufmann ◽

Karlhans Fru ◽

Ethan Babcock ◽

...

Keyword(s):

T Cells ◽

T Cell ◽

Cd4 T Cells ◽

T Cell Responses ◽

Rapid Loss ◽

Cell Responses ◽

Acute Hiv ◽

Hiv 1

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Specific ActivationIn Vivoof HIV-1 by a Bromodomain Inhibitor from Monocytic Cells in Humanized Mice under Antiretroviral Therapy

Journal of Virology ◽

10.1128/jvi.00233-19 ◽

2019 ◽

Vol 93 (12) ◽

Cited By ~ 2

Author(s):

Guangming Li ◽

Zheng Zhang ◽

Natalia Reszka-Blanco ◽

Feng Li ◽

Liqun Chi ◽

...

Keyword(s):

Gene Expression ◽

T Cells ◽

Antiretroviral Therapy ◽

Cd4 T Cells ◽

Myeloid Cells ◽

Humanized Mice ◽

Monocytic Cells ◽

Hiv 1

ABSTRACTCombination antiretroviral therapy (cART) effectively suppresses HIV-1 replication and enables HIV‑infected individuals to live long, productive lives. However, the persistence of HIV-1 reservoirs of both T and myeloid cells with latent or low-replicating HIV-1 in patients under cART makes HIV-1 infection an incurable disease. Recent studies have focused on the development of strategies to activate and purge these reservoirs. Bromodomain and extraterminal domain proteins (BETs) are epigenetic readers involved in modulating gene expression. Several bromodomain inhibitors (BETi) are reported to activate viral transcriptionin vitroin HIV-1 latency cell lines in a P-TEFb (CDK9/cyclin T1)-dependent manner. Little is known about BETi efficacy in activating HIV-1 reservoir cells under cARTin vivo. Here we report that a BETi (I-BET151) efficiently activated HIV-1 reservoirs under effective cART in humanized micein vivo. Interestingly, I-BET151 during suppressive cARTin vivoactivated HIV-1 gene expression only in monocytic cells and not in CD4+T cells. We further demonstrate that BETi preferentially enhanced HIV-1 gene expression in monocytic cells rather than in T cells and that whereas CDK9 was involved in activating HIV-1 by I-BET151 in both monocytic and T cells, CDK2 enhanced HIV-1 transcription in monocytic cells but inhibited it in T cells. Our findings reveal a role for CDK2 in differential modulation of HIV-1 gene expression in myeloid cells and in T cells and provide a novel strategy to reactivate monocytic reservoirs with BETi during cART.IMPORTANCEBromodomain inhibitors have been reported to activate HIV-1 transcriptionin vitro, but their effect on activation of HIV-1 reservoirs during cARTin vivois unclear. We found that BETi (I-BET151) treatment reactivated HIV-1 gene expression in humanized mice during suppressive cART. Interestingly, I-BET151 preferentially reactivated HIV-1 gene expression in monocytic cells, but not in CD4 T cells, in cART-treated mice. Furthermore, I-BET151 significantly increased HIV-1 transcription in monocytic cells, but not in HIV-1-infected CD4 T cells, via CDK2-dependent mechanisms. Our findings suggest that BETi can preferentially activate monocytic HIV-1 reservoir cells and that a combination of reservoir activation agents targeting different cell types and pathways is needed to achieve reactivation of different HIV-1 reservoir cells during cART.

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HIV‐1 upregulates Fas ligand expression in CD4 + T cells in vitro and in vivo : association with Fas‐mediated apoptosis and modulation by aurintricarboxylic acid

Immunology ◽

10.1046/j.1365-2567.1996.510589.x ◽

1996 ◽

Vol 87 (4) ◽

pp. 581-585 ◽

Cited By ~ 83

Author(s):

D. MITRA ◽

M. STEINER ◽

D. H. LYNCH ◽

L. STAIANO‐COICO ◽

J. LAURENCE

Keyword(s):

T Cells ◽

Cd4 T Cells ◽

Fas Ligand ◽

Aurintricarboxylic Acid ◽

Ligand Expression ◽

Hiv 1

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Comprehensive Cross-Clade Characterization of Antibody-Mediated Recognition, Complement-Mediated Lysis, and Cell-Mediated Cytotoxicity of HIV-1 Envelope-Specific Antibodies toward Eradication of the HIV-1 Reservoir

Journal of Virology ◽

10.1128/jvi.00634-17 ◽

2017 ◽

Vol 91 (16) ◽

Cited By ~ 15

Author(s):

Shariq Mujib ◽

Jun Liu ◽

A. K. M. Nur-ur Rahman ◽

Jordan A. Schwartz ◽

Phil Bonner ◽

...

Keyword(s):

T Cells ◽

Cd4 T Cells ◽

Neutralizing Antibodies ◽

Specific Antibodies ◽

Global Epidemic ◽

Infected Cells ◽

Hiv 1 ◽

Hiv Aids

ABSTRACT Immunotherapy with passive administration of broadly neutralizing HIV-1 envelope-specific antibodies (bnAbs) in the setting of established infection in vivo has yielded mixed results. The contribution of different antibodies toward the direct elimination of infected cells is poorly understood. In this study, we determined the ability of 12 well-characterized anti-HIV-1 neutralizing antibodies to recognize and eliminate primary CD4 T cells infected with HIV-1 belonging to clades A, B, C, and D, via antibody-dependent complement-mediated lysis (ADCML) and antibody-dependent cell-mediated cytotoxicity (ADCC), in vitro. We further tested unique combinations of these antibodies to determine the optimal antibody cocktails to be tested in future clinical trials. We report that antibody binding to infected CD4 T cells is highly variable and correlates with ADCML and ADCC processes. Particularly, antibodies targeting the envelope glycan shield (2G12) and V1/V2 site (PG9, PG16, and PGT145) are best at recognizing HIV-1-infected CD4 T cells. However, only PG9 and PG16 and their combinations with other bnAbs sufficiently induced the elimination of HIV-1-infected CD4 T cells by ADCML, ADCC, or both. Notably, CD4 binding site antibodies VRC01, 3BNC117, and NIH45-46 G54W did not exhibit recognition of infected cells and were unable to induce their killing. Future trials geared toward the development of a cure for HIV/AIDS should incorporate V1/V2 antibodies for maximal clearance of infected cells. With the use of only primary immune cells, we conducted a comprehensive cross-clade physiological analysis to aid the direction of antibodies as therapeutics toward the development of a cure for HIV/AIDS. IMPORTANCE Several antibodies capable of neutralizing the majority of circulating HIV-1 strains have been identified to date and have been shown to prevent infection in animal models. However, the use of combinations of such broadly neutralizing antibodies (bnAbs) for the treatment and eradication of HIV-1 in infected humans remains uncertain. In this study, we tested the ability of bnAbs to directly recognize and eliminate primary human CD4 T cells infected with diverse HIV-1 strains representative of the global epidemic by antibody-dependent pathways. We also tested several combinations of bnAbs in our assays in order to maximize the clearance of infected cells. We show that the ability of bnAbs to identify and kill infected cells is highly variable and that only a few of them are able to exert this function. Our data will help guide the formulation of bnAbs to test in future human trials aimed at the development of a cure.

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