Alprazolam Prompts HIV-1 Transcriptional Reactivation and Enhances CTL Response Through RUNX1 Inhibition and STAT5 Activation

The HIV-1 pandemic is a significant challenge to the field of medicine. Despite advancements in antiretroviral (ART) development, 38 million people worldwide still live with this disease without a cure. A significant barrier to the eradication of HIV-1 lies in the persistently latent pool that establishes early in the infection. The “shock and kill” strategy relies on the discovery of a latency-reversing agent (LRA) that can robustly reactivate the latent pool and not limit immune clearance. We have found that a benzodiazepine (BDZ), that is commonly prescribed for panic and anxiety disorder, to be an ideal candidate for latency reversal. The BDZ Alprazolam functions as an inhibitor of the transcription factor RUNX1, which negatively regulates HIV-1 transcription. In addition to the displacement of RUNX1 from the HIV-1 5′LTR, Alprazolam potentiates the activation of STAT5 and its recruitment to the viral promoter. The activation of STAT5 in cytotoxic T cells may enable immune activation which is independent of the IL-2 receptor. These findings have significance for the potential use of Alprazolam in a curative strategy and to addressing the neuroinflammation associated with neuroHIV-1.

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Interferon Alpha Enhances NK Cell Function and the Suppressive Capacity of HIV-Specific CD8+T Cells

Journal of Virology ◽

10.1128/jvi.01541-18 ◽

2018 ◽

Vol 93 (3) ◽

Cited By ~ 7

Author(s):

Abena K. R. Kwaa ◽

Chloe A. G. Talana ◽

Joel N. Blankson

Keyword(s):

T Cells ◽

T Cell ◽

Nk Cells ◽

Effector Cell ◽

Cell Function ◽

Nk Cell ◽

Suppressive Capacity ◽

Short Course ◽

Shock And Kill ◽

Hiv 1

ABSTRACTCurrent shock-and-kill strategies for the eradication of the HIV-1 reservoir have resulted in blips of viremia but not in a decrease in the size of the latent reservoir in patients on suppressive antiretroviral therapy (ART). This discrepancy could potentially be explained by an inability of the immune system to kill HIV-1-infected cells following the reversal of latency. Furthermore, some studies have suggested that certain latency-reversing agents (LRAs) may inhibit CD8+T cell and natural killer (NK) cell responses. In this study, we tested the hypothesis that alpha interferon (IFN-α) could improve the function of NK cells from chronic progressors (CP) on ART. We show here that IFN-α treatment enhanced cytokine secretion, polyfunctionality, degranulation, and the cytotoxic potential of NK cells from healthy donors (HD) and CP. We also show that this cytokine enhanced the viral suppressive capacity of NK cells from HD and elite controllers or suppressors. Furthermore, IFN-α enhanced global CP CD8+T cell cytokine responses and the suppressive capacity of ES CD8+T cells. Our data suggest that IFN-α treatment may potentially be used as an immunomodulatory agent in HIV-1 cure strategies.IMPORTANCEData suggest that HIV+individuals unable to control infection fail to do so due to impaired cytokine production and/cytotoxic effector cell function. Consequently, the success of cure agendas such as the shock-and-kill strategy will probably depend on enhancing patient effector cell function. In this regard, NK cells are of particular interest since they complement the function of CD8+T cells. Here, we demonstrate the ability of short-course alpha interferon (IFN-α) treatments to effectively enhance such effector functions in chronic progressor NK cells without inhibiting their general CD8+T cell function. These results point to the possibility of exploring such short-course IFN-α treatments for the enhancement of effector cell function in HIV+patients in future cure strategies.

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Notwithstanding Circumstantial Alibis, Cytotoxic T Cells Can Be Major Killers of HIV-1-Infected Cells

Journal of Virology ◽

10.1128/jvi.00306-16 ◽

2016 ◽

Vol 90 (16) ◽

pp. 7066-7083 ◽

Cited By ~ 14

Author(s):

Saikrishna Gadhamsetty ◽

Tim Coorens ◽

Rob J. de Boer

Keyword(s):

T Cells ◽

Viral Replication ◽

Cytotoxic T Cells ◽

Chronic Phase ◽

Replication Rate ◽

Immunodeficiency Virus ◽

Infected Cells ◽

Eclipse Phase ◽

Hiv 1

ABSTRACTSeveral experiments suggest that in the chronic phase of human immunodeficiency virus type 1 (HIV-1) infection, CD8+cytotoxic T lymphocytes (CTL) contribute very little to the death of productively infected cells. First, the expected life span of productively infected cells is fairly long, i.e., about 1 day. Second, this life span is hardly affected by the depletion of CD8+T cells. Third, the rate at which mutants escaping a CTL response take over the viral population tends to be slow. Our main result is that all these observations are perfectly compatible with killing rates that are much faster than one per day once we invoke the fact that infected cells proceed through an eclipse phase of about 1 day before they start producing virus. Assuming that the major protective effect of CTL is cytolytic, we demonstrate that mathematical models with an eclipse phase account for the data when the killing is fast and when it varies over the life cycle of infected cells. Considering the steady state corresponding to the chronic phase of the infection, we find that the rate of immune escape and the rate at which the viral load increases following CD8+T cell depletion should reflect the viral replication rate, ρ. A meta-analysis of previous data shows that viral replication rates during chronic infection vary between 0.5 ≤ ρ ≤ 1 day−1. Balancing such fast viral replication requires killing rates that are several times larger than ρ, implying that most productively infected cells would die by cytolytic effects.IMPORTANCEMost current data suggest that cytotoxic T cells (CTL) mediate their control of human immunodeficiency virus type 1 (HIV-1) infection by nonlytic mechanisms; i.e., the data suggest that CTL hardly kill. This interpretation of these data has been based upon the general mathematical model for HIV infection. Because this model ignores the eclipse phase between the infection of a target cell and the start of viral production by that cell, we reanalyze the same data sets with novel models that do account for the eclipse phase. We find that the data are perfectly consistent with lytic control by CTL and predict that most productively infected cells are killed by CTL. Because the killing rate should balance the viral replication rate, we estimate both parameters from a large set of published experiments in which CD8+T cells were depleted in simian immunodeficiency virus (SIV)-infected monkeys. This confirms that the killing rate can be much faster than is currently appreciated.

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A stronger transcription regulatory circuit of HIV-1C drives the rapid establishment of latency with implications for the direct involvement of Tat

10.1101/2020.02.20.958892 ◽

2020 ◽

Author(s):

Sutanuka Chakraborty ◽

Manisha Kabi ◽

Udaykumar Ranga

Keyword(s):

Transcription Factor ◽

Viral Infection ◽

Viral Vectors ◽

Transcription Factor Binding ◽

Jurkat Cells ◽

Subtype C ◽

Viral Promoter ◽

Factor Binding ◽

Transcriptional Silence ◽

Hiv 1

AbstractThe magnitude of transcription factor binding site variation emerging in HIV-1C, especially the addition of NF-κB motifs by sequence duplication, makes the examination of transcriptional silence challenging. How can HIV-1 establish and maintain latency despite having a strong LTR? We constructed panels of sub-genomic reporter viral vectors with varying copy numbers of NF-κB motifs (0 to 4 copies) and examined the profile of latency establishment in Jurkat cells. We found surprisingly that the stronger the viral promoter, the faster the latency establishment. Importantly, at the time of commitment to latency and subsequent points, Tat levels in the cell were not limiting. Using highly sensitive strategies, we demonstrate the presence of Tat in the latent cell, recruited to the latent LTR. Our data allude, for the first time, to Tat establishing a negative feedback loop during the late phases of viral infection, leading to the rapid silencing of the viral promoter.ImportanceOver the past 10-15 years, HIV-1C has been evolving rapidly towards gaining stronger transcriptional activity by sequence duplication of major transcription factor binding sites. The duplication of NF-κB motifs is unique and exclusive for HIV-1C, a property not shared with any of the other eight HIV-1 genetic families. What mechanism(s) does HIV-1C employ to establish and maintain transcriptional silence despite the presence of a strong promoter and a concomitant strong, positive transcriptional feedback is the primary question we attempted to address in the present manuscript. The role Tat plays in latency reversal is well established. Our work with the most common HIV-1 subtype C (HIV-1C) offers crucial leads towards Tat possessing a dual-role in serving both as transcriptional activator and repressor at different phases of the viral infection of the cell. The leads we offer through the present work have significant implications for HIV-1 cure research.

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The evolution of regulatory elements in the emerging promoter variant strains of HIV-1

10.1101/2021.04.28.441760 ◽

2021 ◽

Author(s):

Disha Bhange ◽

Nityanand Prasad ◽

Swati Singh ◽

Harshit Kumar Prajapati ◽

Shesh Prakash Maurya ◽

...

Keyword(s):

Viral Latency ◽

Regulatory Elements ◽

The Other ◽

Clinical Samples ◽

Latent Reservoir ◽

Viral Gene ◽

Viral Promoter ◽

Reservoir Characteristics ◽

Hiv 1

AbstractIn a multicentric, observational, investigator-blinded, and longitudinal clinical study of 764 ART-naïve subjects, we identified nine different promoter-variant strains of HIV-1 subtype C (HIV-1C) emerging in the Indian population, with some of these variants being reported for the first time. Unlike several previous studies, our work here focuses on the evolving viral regulatory elements, not coding sequences. The emerging viral strains contain additional copies of the existing transcription factor binding sites (TFBS), including TCF-1α/LEF-1, RBEIII, AP-1, and NF-κB, created by sequence duplication. The additional TFBS are genetically diverse and may blur the distinction between the modulatory region of the promoter and the viral enhancer. In a follow-up analysis, we found trends, but not significant associations between any specific variant promoter and prognostic markers, probably because the emerging viral strains might not have established mono infections yet. Illumina sequencing of four clinical samples containing a co-infection indicated the domination of one strain over the other and establishing a stable ratio with the second strain at the follow-up time-points. Since a single promoter regulates viral gene expression and constitutes the master regulatory circuit with Tat, the acquisition of additional and variant copies of the TFBS may significantly impact viral latency and latent reservoir characteristics. Further studies are urgently warranted to understand how the diverse TFBS profiles of the viral promoter may modulate the characteristics of the latent reservoir, especially following the initiation of antiretroviral therapy.Significance StatementA unique conglomeration of TFBS enables the HIV-1 promoter to accomplish two diametrically opposite functions – transcriptional activation and transcriptional silencing. The various phases of viral latency - establishment, maintenance, and reversal - collectively determine the replication fitness of individual viral strains. A profound variation in the TFBS composition of the viral promoter may significantly alter the viral latency properties and the latent reservoir characteristics. Although the duplication of certain TFBS remains a quality unique to HIV-1C, the high-level genetic recombination of HIV-1 may promote the transfer of such molecular properties to the other HIV-1 subtypes. The emergence of several promoter-variant viral strains may make the task of a ‘functional cure’ more challenging in HIV-1C.

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Resveratrol Promotes HIV-1 Tat Accumulation via AKT/FOXO1 Signaling Axis and Potentiates Vorinostat to antagonize HIV-1 latency

Current HIV Research ◽

10.2174/1570162x19666210118151249 ◽

2021 ◽

Vol 19 ◽

Author(s):

Zeming Feng ◽

Zhengrong Yang ◽

Xiang Gao ◽

Yuhua Xue ◽

Xiaohui Wang

Keyword(s):

Host Cells ◽

Latent Reservoir ◽

Cell Models ◽

Elongation Complex ◽

Major Barrier ◽

Small Nuclear Ribonucleoprotein ◽

Candidate Drug ◽

Signaling Axis ◽

Shock And Kill ◽

Hiv 1

Background: The latent reservoir of HIV-1 is a major barrier to achieving the eradication of HIV-1/AIDS. One strategy is termed “shock and kill”, which aims to awaken the latent HIV-1 using latency reversing agents (LRAs) to replicate and produce HIV-1 particles. Subsequently, the host cells containing HIV-1 can be recognized and eliminated by the immune response and anti-retroviral therapy. Although many LRAs have been found and tested, their clinical trials were dissatisfactory. Objective: To study how resveratrol reactivating silent HIV-1 transcription and assess if resveratrol could be a candidate drug for the “shock” phase in “shock and kill” strategy. Method: We used established HIV-1 transcription cell models (HeLa-based NH1 and NH2 cells) and HIV-1 latent cell models (J-Lat A72 and Jurkat 2D10 cells). We performed resveratrol treatment on these cell lines and studied the mechanism of how resveratrol stimulating HIV-1 gene transcription. We also tested resveratrol’s bioactivity on primary cells isolated from HIV1 latent infected patients. Results: Resveratrol promoted HIV-1 Tat protein levels, and resveratrol-induced Tat promotion was dependent on the AKT/FOXO1 signaling axis. Resveratrol could partially dissociate P-TEFb (Positive Transcription Elongation Factor b) from 7SK snRNP (7SK small nuclear Ribonucleoprotein) and promote Tat-SEC (Super Elongation Complex) interaction. Preclinical studies showed that resveratrol potentiated Vorinostat to awaken HIV-1 latency in HIV-1 latent infected cells isolated from patients. Conclusion: We found a new mechanism of resveratrol stimulating the production of HIV-1. Resveratrol could be a promising candidate drug to eradicate HIV-1 reservoirs.

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Selection of escape mutation by Pol154-162-specific cytotoxic T cells among chronically HIV-1-infected HLA-B*5401-positive individuals

Human Immunology ◽

10.1016/j.humimm.2009.10.015 ◽

2010 ◽

Vol 71 (2) ◽

pp. 123-127 ◽

Cited By ~ 2

Author(s):

Masao Hashimoto ◽

Mitsutaka Kitano ◽

Kazutaka Honda ◽

Hirokazu Koizumi ◽

Sachi Dohki ◽

...

Keyword(s):

T Cells ◽

Cytotoxic T Cells ◽

Escape Mutation ◽

Hiv 1 ◽

Selection Of

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Expression of functional HIV-1 integrase in the yeastSaccharomyces cerevisiae leads to the emergence of a lethal phenotype: potential use for inhibitor screening

Current Genetics ◽

10.1007/bf02426953 ◽

1996 ◽

Vol 29 (6) ◽

pp. 503-510 ◽

Cited By ~ 20

Author(s):

Anne B. Caumont ◽

Gordon A. Jamieson ◽

Sergio Pichuantes ◽

Anton Tien Nguyen ◽

Simon Litvak ◽

...

Keyword(s):

Inhibitor Screening ◽

Lethal Phenotype ◽

Potential Use ◽

Hiv 1

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Generation of Cytotoxic T Cells Against Virus-Infected Human Brain Macrophages in a Murine Model of HIV-1 Encephalitis

The Journal of Immunology ◽

10.4049/jimmunol.168.10.5376-a ◽

2002 ◽

Vol 168 (10) ◽

pp. 5376.2-5376

Author(s):

Larisa Y. Poluektova ◽

David H. Munn ◽

Yuri Persidsky ◽

Howard E. Gendelman

Keyword(s):

T Cells ◽

Human Brain ◽

Murine Model ◽

Cytotoxic T Cells ◽

Brain Macrophages ◽

Hiv 1

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HLA-unrestricted killing of HIV-1 gag protein-expressing CD4 T cells by gag-specific CD8 cytotoxic T cells

AIDS ◽

10.1097/00002030-199908200-00021 ◽

1999 ◽

Vol 13 (12) ◽

pp. 1583 ◽

Cited By ~ 1

Author(s):

Rosângela Salerno-Gonçalves ◽

Wei Lu ◽

Ammar Achour ◽

Jean-Marie Andrieu

Keyword(s):

T Cells ◽

Cd4 T Cells ◽

Cytotoxic T Cells ◽

Gag Protein ◽

Hiv 1

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Clinical Control of HIV-1 by Cytotoxic T Cells Specific for Multiple Conserved Epitopes

Journal of Virology ◽

10.1128/jvi.00020-15 ◽

2015 ◽

Vol 89 (10) ◽

pp. 5330-5339 ◽

Cited By ~ 39

Author(s):

Hayato Murakoshi ◽

Tomohiro Akahoshi ◽

Madoka Koyanagi ◽

Takayuki Chikata ◽

Takuya Naruto ◽

...

Keyword(s):

T Cells ◽

Synergistic Effects ◽

Cytotoxic T Cells ◽

Effective Control ◽

Aids Vaccine ◽

Subtype B ◽

Aids Vaccines ◽

B 52 ◽

Hiv 1

ABSTRACTIdentification and characterization of CD8+T cells effectively controlling HIV-1 variants are necessary for the development of AIDS vaccines and for studies of AIDS pathogenesis, although such CD8+T cells have been only partially identified. In this study, we sought to identify CD8+T cells controlling HIV-1 variants in 401 Japanese individuals chronically infected with HIV-1 subtype B, in which protective alleles HLA-B*57 and HLA-B*27 are very rare, by using comprehensive and exhaustive methods. We identified 13 epitope-specific CD8+T cells controlling HIV-1 in Japanese individuals, though 9 of these epitopes were not previously reported. The breadths of the T cell responses to the 13 epitopes were inversely associated with plasma viral load (P= 2.2 × 10−11) and positively associated with CD4 count (P= 1.2 × 10−11), indicating strong synergistic effects of these T cells on HIV-1 controlin vivo. Nine of these epitopes were conserved among HIV-1 subtype B-infected individuals, whereas three out of four nonconserved epitopes were cross-recognized by the specific T cells. These findings indicate that these 12 epitopes are strong candidates for antigens for an AIDS vaccine. The present study highlighted a strategy to identify CD8+T cells controlling HIV-1 and demonstrated effective control of HIV-1 by those specific for 12 conserved or cross-reactive epitopes.IMPORTANCEHLA-B*27-restricted and HLA-B*57-restricted cytotoxic T lymphocytes (CTLs) play a key role in controlling HIV-1 in Caucasians and Africans, whereas it is unclear which CTLs control HIV-1 in Asian countries, where HLA-B*57 and HLA-B*27 are very rare. A recent study showed that HLA-B*67:01 and HLA-B*52:01-C*12:02 haplotypes were protective alleles in Japanese individuals, but it is unknown whether CTLs restricted by these alleles control HIV-1. In this study, we identified 13 CTLs controlling HIV-1 in Japan by using comprehensive and exhaustive methods. They included 5 HLA-B*52:01-restricted and 3 HLA-B*67:01-restricted CTLs, suggesting that these CTLs play a predominant role in HIV-1 control. The 13 CTLs showed synergistic effects on HIV-1 control. Twelve out of these 13 epitopes were recognized as conserved or cross-recognized ones. These findings strongly suggest that these 12 epitopes are candidates for antigens for AIDS vaccines.

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