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Nguyen K, Karn J. The sounds of silencing: dynamic epigenetic control of HIV latency. Curr Opin HIV AIDS 2024; 19:102-109. [PMID: 38547337 PMCID: PMC10990033 DOI: 10.1097/coh.0000000000000850] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/04/2024]
Abstract
PURPOSE OF REVIEW This review highlights advances in understanding the epigenetic control mechanisms that regulate HIV-1 latency mechanisms in T-cells and microglial cells and describes the potential of current therapeutic approaches targeting the epigenetic machinery to eliminate or block the HIV-1 latent reservoir. RECENT FINDINGS Large-scale unbiased CRISPR-Cas9 library-based screenings, coupled with biochemical studies, have comprehensively identified the epigenetic factors pivotal in regulating HIV-1 latency, paving the way for potential novel targets in therapeutic development. These studies also highlight how the bivalency observed at the HIV-1 5'LTR primes latent proviruses for rapid reactivation. SUMMARY The HIV-1 latent is established very early during infection, and its persistence is the major obstacle to achieving an HIV-1 cure. Here, we present a succinct summary of the latest research findings, shedding light on the pivotal roles played by host epigenetic machinery in the control of HIV-1 latency. Newly uncovered mechanisms permitting rapid reversal of epigenetic restrictions upon viral reactivation highlight the formidable challenges of achieving enduring and irreversible epigenetic silencing of HIV-1.
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Affiliation(s)
- Kien Nguyen
- Department of Molecular Biology & Microbiology, Case Western Reserve University School of Medicine, Cleveland, Ohio, USA
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2
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Kizito F, Nguyen K, Mbonye U, Shukla M, Luttge B, Checkley MA, Agaponova A, Leskov K, Karn J. Structural rearrangements in the nucleus localize latent HIV proviruses to a perinucleolar compartment supportive of reactivation. Proc Natl Acad Sci U S A 2024; 121:e2202003121. [PMID: 38669184 PMCID: PMC11067448 DOI: 10.1073/pnas.2202003121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2022] [Accepted: 03/12/2024] [Indexed: 04/28/2024] Open
Abstract
Using an immunofluorescence assay based on CRISPR-dCas9-gRNA complexes that selectively bind to the HIV LTR (HIV Cas-FISH), we traced changes in HIV DNA localization in primary effector T cells from early infection until the cells become quiescent as they transition to memory cells. Unintegrated HIV DNA colocalized with CPSF6 and HIV capsid (CA, p24) was found in the cytoplasm and nuclear periphery at days 1 and 3 post infection. From days 3 to 7, most HIV DNA was distributed primarily in the nuclear intermediate euchromatic compartment and was transcribed. By day 21, the cells had entered quiescence, and HIV DNA accumulated in the perinucleolar compartment (PNC). The localization of proviruses to the PNC was blocked by integrase inhibitor Raltegravir, suggesting it was due to chromosomal rearrangements. During the reactivation of latently infected cells through the T cell receptor (TCR), nascent viral mRNA transcripts associated with HIV DNA in the PNC were detected. The viral trans-activator Tat and its regulatory partners, P-TEFb and 7SK snRNA, assembled in large interchromatin granule clusters near the provirus within 2 h of TCR activation. As T cell activation progressed, the HIV DNA shifted away from the PNC. HIV DNA in latently infected memory T cells from patients also accumulated in the PNC and showed identical patterns of nuclear rearrangements after cellular reactivation. Thus, in contrast to transformed cells where proviruses are found primarily at the nuclear periphery, in primary memory T cells, the nuclear architecture undergoes rearrangements that shape the transcriptional silencing and reactivation of proviral HIV.
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Affiliation(s)
- Fredrick Kizito
- Department of Molecular Biology and Microbiology, School of Medicine, Case Western Reserve University, Cleveland, OH44106
| | - Kien Nguyen
- Department of Molecular Biology and Microbiology, School of Medicine, Case Western Reserve University, Cleveland, OH44106
| | - Uri Mbonye
- Department of Molecular Biology and Microbiology, School of Medicine, Case Western Reserve University, Cleveland, OH44106
| | - Meenakshi Shukla
- Department of Molecular Biology and Microbiology, School of Medicine, Case Western Reserve University, Cleveland, OH44106
| | - Benjamin Luttge
- Department of Molecular Biology and Microbiology, School of Medicine, Case Western Reserve University, Cleveland, OH44106
| | - Mary Ann Checkley
- Department of Molecular Biology and Microbiology, School of Medicine, Case Western Reserve University, Cleveland, OH44106
| | - Anna Agaponova
- Department of Molecular Biology and Microbiology, School of Medicine, Case Western Reserve University, Cleveland, OH44106
| | - Konstantin Leskov
- Department of Molecular Biology and Microbiology, School of Medicine, Case Western Reserve University, Cleveland, OH44106
| | - Jonathan Karn
- Department of Molecular Biology and Microbiology, School of Medicine, Case Western Reserve University, Cleveland, OH44106
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Mbonye U, Karn J. The cell biology of HIV-1 latency and rebound. Retrovirology 2024; 21:6. [PMID: 38580979 PMCID: PMC10996279 DOI: 10.1186/s12977-024-00639-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/07/2024] Open
Abstract
Transcriptionally latent forms of replication-competent proviruses, present primarily in a small subset of memory CD4+ T cells, pose the primary barrier to a cure for HIV-1 infection because they are the source of the viral rebound that almost inevitably follows the interruption of antiretroviral therapy. Over the last 30 years, many of the factors essential for initiating HIV-1 transcription have been identified in studies performed using transformed cell lines, such as the Jurkat T-cell model. However, as highlighted in this review, several poorly understood mechanisms still need to be elucidated, including the molecular basis for promoter-proximal pausing of the transcribing complex and the detailed mechanism of the delivery of P-TEFb from 7SK snRNP. Furthermore, the central paradox of HIV-1 transcription remains unsolved: how are the initial rounds of transcription achieved in the absence of Tat? A critical limitation of the transformed cell models is that they do not recapitulate the transitions between active effector cells and quiescent memory T cells. Therefore, investigation of the molecular mechanisms of HIV-1 latency reversal and LRA efficacy in a proper physiological context requires the utilization of primary cell models. Recent mechanistic studies of HIV-1 transcription using latently infected cells recovered from donors and ex vivo cellular models of viral latency have demonstrated that the primary blocks to HIV-1 transcription in memory CD4+ T cells are restrictive epigenetic features at the proviral promoter, the cytoplasmic sequestration of key transcription initiation factors such as NFAT and NF-κB, and the vanishingly low expression of the cellular transcription elongation factor P-TEFb. One of the foremost schemes to eliminate the residual reservoir is to deliberately reactivate latent HIV-1 proviruses to enable clearance of persisting latently infected cells-the "Shock and Kill" strategy. For "Shock and Kill" to become efficient, effective, non-toxic latency-reversing agents (LRAs) must be discovered. Since multiple restrictions limit viral reactivation in primary cells, understanding the T-cell signaling mechanisms that are essential for stimulating P-TEFb biogenesis, initiation factor activation, and reversing the proviral epigenetic restrictions have become a prerequisite for the development of more effective LRAs.
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Affiliation(s)
- Uri Mbonye
- Department of Molecular Biology and Microbiology, Case Western Reserve University School of Medicine, Cleveland, OH, 44106, USA.
| | - Jonathan Karn
- Department of Molecular Biology and Microbiology, Case Western Reserve University School of Medicine, Cleveland, OH, 44106, USA.
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Rausch JW, Parvez S, Pathak S, Capoferri AA, Kearney MF. HIV Expression in Infected T Cell Clones. Viruses 2024; 16:108. [PMID: 38257808 PMCID: PMC10820123 DOI: 10.3390/v16010108] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2023] [Revised: 01/04/2024] [Accepted: 01/06/2024] [Indexed: 01/24/2024] Open
Abstract
The principal barrier to an HIV-1 cure is the persistence of infected cells harboring replication-competent proviruses despite antiretroviral therapy (ART). HIV-1 transcriptional suppression, referred to as viral latency, is foremost among persistence determinants, as it allows infected cells to evade the cytopathic effects of virion production and killing by cytotoxic T lymphocytes (CTL) and other immune factors. HIV-1 persistence is also governed by cellular proliferation, an innate and essential capacity of CD4+ T cells that both sustains cell populations over time and enables a robust directed response to immunological threats. However, when HIV-1 infects CD4+ T cells, this capacity for proliferation can enable surreptitious HIV-1 propagation without the deleterious effects of viral gene expression in latently infected cells. Over time on ART, the HIV-1 reservoir is shaped by both persistence determinants, with selective forces most often favoring clonally expanded infected cell populations harboring transcriptionally quiescent proviruses. Moreover, if HIV latency is incomplete or sporadically reversed in clonal infected cell populations that are replenished faster than they are depleted, such populations could both persist indefinitely and contribute to low-level persistent viremia during ART and viremic rebound if treatment is withdrawn. In this review, select genetic, epigenetic, cellular, and immunological determinants of viral transcriptional suppression and clonal expansion of HIV-1 reservoir T cells, interdependencies among these determinants, and implications for HIV-1 persistence will be presented and discussed.
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Affiliation(s)
- Jason W. Rausch
- HIV Dynamics and Replication Program, Center for Cancer Research, National Cancer Institute, Frederick, MD 21702, USA; (S.P.); (S.P.); (A.A.C.); (M.F.K.)
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5
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Cobos Jiménez V, Geretz A, Tokarev A, Ehrenberg PK, Deletsu S, Machmach K, Mudvari P, Howard JN, Zelkoski A, Paquin-Proulx D, Del Prete GQ, Subra C, Boritz EA, Bosque A, Thomas R, Bolton DL. AP-1/c-Fos supports SIV and HIV-1 latency in CD4 T cells infected in vivo. iScience 2023; 26:108015. [PMID: 37860759 PMCID: PMC10582365 DOI: 10.1016/j.isci.2023.108015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2023] [Revised: 08/24/2023] [Accepted: 09/18/2023] [Indexed: 10/21/2023] Open
Abstract
Persistent HIV-1 reservoirs of infected CD4 T cells are a major barrier to HIV-1 cure, although the mechanisms by which they are established and maintained in vivo remain poorly characterized. To elucidate host cell gene expression patterns that govern virus gene expression, we analyzed viral RNA+ (vRNA) CD4 T cells of untreated simian immunodeficiency virus (SIV)-infected macaques by single-cell RNA sequencing. A subset of vRNA+ cells distinguished by spliced and high total vRNA (7-10% of reads) expressed diminished FOS, a component of the Activator protein 1 (AP-1) transcription factor, relative to vRNA-low and -negative cells. Conversely, FOS and JUN, another AP-1 component, were upregulated in HIV DNA+ infected cells compared to uninfected cells from people with HIV-1 on suppressive therapy. Inhibiting c-Fos in latently infected primary cells augmented reactivatable HIV-1 infection. These findings implicate AP-1 in latency establishment and maintenance and as a potential therapeutic target to limit HIV-1 reservoirs.
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Affiliation(s)
- Viviana Cobos Jiménez
- US Military HIV Research Program, Walter Reed Army Institute of Research, Silver Spring, MD, USA
- The Henry M. Jackson Foundation for the Advancement of Military Medicine, Bethesda, MD, USA
| | - Aviva Geretz
- US Military HIV Research Program, Walter Reed Army Institute of Research, Silver Spring, MD, USA
- The Henry M. Jackson Foundation for the Advancement of Military Medicine, Bethesda, MD, USA
| | - Andrey Tokarev
- US Military HIV Research Program, Walter Reed Army Institute of Research, Silver Spring, MD, USA
- The Henry M. Jackson Foundation for the Advancement of Military Medicine, Bethesda, MD, USA
| | - Philip K. Ehrenberg
- US Military HIV Research Program, Walter Reed Army Institute of Research, Silver Spring, MD, USA
| | | | - Kawthar Machmach
- US Military HIV Research Program, Walter Reed Army Institute of Research, Silver Spring, MD, USA
- The Henry M. Jackson Foundation for the Advancement of Military Medicine, Bethesda, MD, USA
| | - Prakriti Mudvari
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | | | - Amanda Zelkoski
- US Military HIV Research Program, Walter Reed Army Institute of Research, Silver Spring, MD, USA
- The Henry M. Jackson Foundation for the Advancement of Military Medicine, Bethesda, MD, USA
| | - Dominic Paquin-Proulx
- US Military HIV Research Program, Walter Reed Army Institute of Research, Silver Spring, MD, USA
- The Henry M. Jackson Foundation for the Advancement of Military Medicine, Bethesda, MD, USA
| | - Gregory Q. Del Prete
- AIDS and Cancer Virus Program, Frederick National Laboratory for Cancer Research, Frederick, MD, USA
| | - Caroline Subra
- US Military HIV Research Program, Walter Reed Army Institute of Research, Silver Spring, MD, USA
- The Henry M. Jackson Foundation for the Advancement of Military Medicine, Bethesda, MD, USA
| | - Eli A. Boritz
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | | | - Rasmi Thomas
- US Military HIV Research Program, Walter Reed Army Institute of Research, Silver Spring, MD, USA
| | - Diane L. Bolton
- US Military HIV Research Program, Walter Reed Army Institute of Research, Silver Spring, MD, USA
- The Henry M. Jackson Foundation for the Advancement of Military Medicine, Bethesda, MD, USA
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Zhu Y, Jiang Z, Liu L, Yang X, Li M, Cheng Y, Xu J, Yin C, Zhu H. Scopoletin Reactivates Latent HIV-1 by Inducing NF-κB Expression without Global T Cell Activation. Int J Mol Sci 2023; 24:12649. [PMID: 37628826 PMCID: PMC10454185 DOI: 10.3390/ijms241612649] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2023] [Revised: 07/25/2023] [Accepted: 08/04/2023] [Indexed: 08/27/2023] Open
Abstract
Reversing HIV-1 latency promotes the killing of infected cells and is essential for cure strategies. However, current latency-reversing agents (LRAs) are not entirely effective and safe in activating latent viruses in patients. In this study, we investigated whether Scopoletin (6-Methoxy-7-hydroxycoumarin), an important coumarin phytoalexin found in plants with multiple pharmacological activities, can reactivate HIV-1 latency and elucidated its underlying mechanism. Using the Jurkat T cell model of HIV-1 latency, we found that Scopoletin can reactivate latent HIV-1 replication with a similar potency to Prostratin and did so in a dose- and time-dependent manner. Moreover, we provide evidence indicating that Scopoletin-induced HIV-1 reactivation involves the nuclear factor kappa B (NF-κB) signaling pathway. Importantly, Scopoletin did not have a stimulatory effect on T lymphocyte receptors or HIV-1 receptors. In conclusion, our study suggests that Scopoletin has the potential to reactivate latent HIV-1 without causing global T-cell activation, making it a promising treatment option for anti-HIV-1 latency strategies.
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Affiliation(s)
- Yuqi Zhu
- State Key Laboratory of Genetic Engineering and Engineering Research Center of Gene Technology, Ministry of Education, Institute of Genetics, School of Life Sciences, Fudan University, Shanghai 200438, China; (Y.Z.); (Z.J.); (L.L.); (X.Y.); (M.L.); (Y.C.); (C.Y.)
| | - Zhengtao Jiang
- State Key Laboratory of Genetic Engineering and Engineering Research Center of Gene Technology, Ministry of Education, Institute of Genetics, School of Life Sciences, Fudan University, Shanghai 200438, China; (Y.Z.); (Z.J.); (L.L.); (X.Y.); (M.L.); (Y.C.); (C.Y.)
| | - Lin Liu
- State Key Laboratory of Genetic Engineering and Engineering Research Center of Gene Technology, Ministry of Education, Institute of Genetics, School of Life Sciences, Fudan University, Shanghai 200438, China; (Y.Z.); (Z.J.); (L.L.); (X.Y.); (M.L.); (Y.C.); (C.Y.)
| | - Xinyi Yang
- State Key Laboratory of Genetic Engineering and Engineering Research Center of Gene Technology, Ministry of Education, Institute of Genetics, School of Life Sciences, Fudan University, Shanghai 200438, China; (Y.Z.); (Z.J.); (L.L.); (X.Y.); (M.L.); (Y.C.); (C.Y.)
| | - Min Li
- State Key Laboratory of Genetic Engineering and Engineering Research Center of Gene Technology, Ministry of Education, Institute of Genetics, School of Life Sciences, Fudan University, Shanghai 200438, China; (Y.Z.); (Z.J.); (L.L.); (X.Y.); (M.L.); (Y.C.); (C.Y.)
| | - Yipeng Cheng
- State Key Laboratory of Genetic Engineering and Engineering Research Center of Gene Technology, Ministry of Education, Institute of Genetics, School of Life Sciences, Fudan University, Shanghai 200438, China; (Y.Z.); (Z.J.); (L.L.); (X.Y.); (M.L.); (Y.C.); (C.Y.)
| | - Jianqing Xu
- Scientific Research Center, Shanghai Public Health Clinical Center, Fudan University, Shanghai 201508, China;
| | - Chunhua Yin
- State Key Laboratory of Genetic Engineering and Engineering Research Center of Gene Technology, Ministry of Education, Institute of Genetics, School of Life Sciences, Fudan University, Shanghai 200438, China; (Y.Z.); (Z.J.); (L.L.); (X.Y.); (M.L.); (Y.C.); (C.Y.)
| | - Huanzhang Zhu
- State Key Laboratory of Genetic Engineering and Engineering Research Center of Gene Technology, Ministry of Education, Institute of Genetics, School of Life Sciences, Fudan University, Shanghai 200438, China; (Y.Z.); (Z.J.); (L.L.); (X.Y.); (M.L.); (Y.C.); (C.Y.)
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7
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Liang T, Li G, Lu Y, Hu M, Ma X. The Involvement of Ubiquitination and SUMOylation in Retroviruses Infection and Latency. Viruses 2023; 15:v15040985. [PMID: 37112965 PMCID: PMC10144533 DOI: 10.3390/v15040985] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2023] [Revised: 04/15/2023] [Accepted: 04/16/2023] [Indexed: 04/29/2023] Open
Abstract
Retroviruses, especially the pathogenic human immunodeficiency virus type 1 (HIV-1), have severely threatened human health for decades. Retroviruses can form stable latent reservoirs via retroviral DNA integration into the host genome, and then be temporarily transcriptional silencing in infected cells, which makes retroviral infection incurable. Although many cellular restriction factors interfere with various steps of the life cycle of retroviruses and the formation of viral latency, viruses can utilize viral proteins or hijack cellular factors to evade intracellular immunity. Many post-translational modifications play key roles in the cross-talking between the cellular and viral proteins, which has greatly determined the fate of retroviral infection. Here, we reviewed recent advances in the regulation of ubiquitination and SUMOylation in the infection and latency of retroviruses, focusing on both host defense- and virus counterattack-related ubiquitination and SUMOylation system. We also summarized the development of ubiquitination- and SUMOylation-targeted anti-retroviral drugs and discussed their therapeutic potential. Manipulating ubiquitination or SUMOylation pathways by targeted drugs could be a promising strategy to achieve a "sterilizing cure" or "functional cure" of retroviral infection.
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Affiliation(s)
- Taizhen Liang
- State Key Laboratory of Respiratory Disease, Guangzhou Medical University, Guangzhou 511400, China
- Guangzhou Laboratory, Guangzhou International Bio-Island, Guangzhou 510005, China
| | - Guojie Li
- State Key Laboratory of Respiratory Disease, Guangzhou Medical University, Guangzhou 511400, China
- Guangzhou Laboratory, Guangzhou International Bio-Island, Guangzhou 510005, China
| | - Yunfei Lu
- Guangzhou Laboratory, Guangzhou International Bio-Island, Guangzhou 510005, China
| | - Meilin Hu
- State Key Laboratory of Respiratory Disease, Guangzhou Medical University, Guangzhou 511400, China
- Guangzhou Laboratory, Guangzhou International Bio-Island, Guangzhou 510005, China
| | - Xiancai Ma
- State Key Laboratory of Respiratory Disease, Guangzhou Medical University, Guangzhou 511400, China
- Guangzhou Laboratory, Guangzhou International Bio-Island, Guangzhou 510005, China
- Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou 510080, China
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Allen AG, Chung CH, Worrell SD, Nwaozo G, Madrid R, Mele AR, Dampier W, Nonnemacher MR, Wigdahl B. Assessment of anti-HIV-1 guide RNA efficacy in cells containing the viral target sequence, corresponding gRNA, and CRISPR/Cas9. Front Genome Ed 2023; 5:1101483. [PMID: 37124096 PMCID: PMC10134072 DOI: 10.3389/fgeed.2023.1101483] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2022] [Accepted: 03/20/2023] [Indexed: 05/02/2023] Open
Abstract
The Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR)/Cas9 gene editing system has been shown to be effective at inhibiting human immunodeficiency virus type 1 (HIV-1). Studies have not consistently used a trackable dual reporter system to determine what cells received the Cas9/gRNA to determine the overall knockdown of HIV. Some studies have used stably transduced cells under drug selection to accomplish this goal. Here a two-color system was used that allows tracking of viral protein expression and which cells received the CRISPR/Cas9 system. These experiments ensured that each gRNA used was a perfect match to the intended target to remove this variable. The data showed that gRNAs targeting the transactivation response element (TAR) region or other highly conserved regions of the HIV-1 genome were effective at stopping viral gene expression, with multiple assays demonstrating greater than 95 percent reduction. Conversely, gRNAs targeting conserved sites of the 5' portion of the U3 region were largely ineffective, demonstrating that the location of edits in the long terminal repeat (LTR) matter with respect to function. In addition, it was observed that a gRNA targeting Tat was effective in a T-cell model of HIV-1 latency. Taken together, these studies demonstrated gRNAs designed to highly conserved functional regions have near 100% efficacy in vitro in cells known to have received the Cas9/gRNA pair.
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Affiliation(s)
- Alexander G. Allen
- Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, PA, United States
- Center for Molecular Virology and Gene Therapy, Institute for Molecular Medicine and Infectious Disease, Drexel University College of Medicine, Philadelphia, PA, United States
| | - Cheng-Han Chung
- Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, PA, United States
- Center for Molecular Virology and Gene Therapy, Institute for Molecular Medicine and Infectious Disease, Drexel University College of Medicine, Philadelphia, PA, United States
| | - Stephen D. Worrell
- Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, PA, United States
- Center for Molecular Virology and Gene Therapy, Institute for Molecular Medicine and Infectious Disease, Drexel University College of Medicine, Philadelphia, PA, United States
| | - Glad Nwaozo
- Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, PA, United States
- Center for Molecular Virology and Gene Therapy, Institute for Molecular Medicine and Infectious Disease, Drexel University College of Medicine, Philadelphia, PA, United States
| | - Rebekah Madrid
- Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, PA, United States
- Center for Molecular Virology and Gene Therapy, Institute for Molecular Medicine and Infectious Disease, Drexel University College of Medicine, Philadelphia, PA, United States
| | - Anthony R. Mele
- Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, PA, United States
- Center for Molecular Virology and Gene Therapy, Institute for Molecular Medicine and Infectious Disease, Drexel University College of Medicine, Philadelphia, PA, United States
| | - Will Dampier
- Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, PA, United States
- Center for Molecular Virology and Gene Therapy, Institute for Molecular Medicine and Infectious Disease, Drexel University College of Medicine, Philadelphia, PA, United States
| | - Michael R. Nonnemacher
- Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, PA, United States
- Center for Molecular Virology and Gene Therapy, Institute for Molecular Medicine and Infectious Disease, Drexel University College of Medicine, Philadelphia, PA, United States
| | - Brian Wigdahl
- Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, PA, United States
- Center for Molecular Virology and Gene Therapy, Institute for Molecular Medicine and Infectious Disease, Drexel University College of Medicine, Philadelphia, PA, United States
- Sidney Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA, United States
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Epigenetic Regulation of HIV-1 Sense and Antisense Transcription in Response to Latency-Reversing Agents. Noncoding RNA 2023; 9:ncrna9010005. [PMID: 36649034 PMCID: PMC9844351 DOI: 10.3390/ncrna9010005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2022] [Revised: 12/29/2022] [Accepted: 01/05/2023] [Indexed: 01/12/2023] Open
Abstract
Nucleosomes positioned on the HIV-1 5' long terminal repeat (LTR) regulate sense transcription as well as the establishment and maintenance of latency. A negative-sense promoter (NSP) in the 3' LTR expresses antisense transcripts with coding and non-coding activities. Previous studies identified cis-acting elements that modulate NSP activity. Here, we used the two chronically infected T cell lines, ACH-2 and J1.1, to investigate epigenetic regulation of NSP activity. We found that histones H3 and H4 are present on the 3' LTR in both cell lines. Following treatment with histone deacetylase inhibitors (HDACi), the levels of H3K27Ac increased and histone occupancy declined. HDACi treatment also led to increased levels of RNA polymerase II (RNPII) at NSP, and antisense transcription was induced with similar kinetics and to a similar extent as 5' LTR-driven sense transcription. We also detected H3K9me2 and H3K27me3 on NSP, along with the enzymes responsible for these epigenetic marks, namely G9a and EZH2, respectively. Treatment with their respective inhibitors had little or no effect on RNPII occupancy at the two LTRs, but it induced both sense and antisense transcription. Moreover, the increased expression of antisense transcripts in response to treatment with a panel of eleven latency-reversing agents closely paralleled and was often greater than the effect on sense transcripts. Thus, HIV-1 sense and antisense RNA expression are both regulated via acetylation and methylation of lysine 9 and 27 on histone H3. Since HIV-1 antisense transcripts act as non-coding RNAs promoting epigenetic silencing of the 5' LTR, our results suggest that the limited efficacy of latency-reversing agents in the context of 'shock and kill' cure strategies may be due to concurrent induction of antisense transcripts thwarting their effect on sense transcription.
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Mbonye U, Kizito F, Karn J. New insights into transcription elongation control of HIV-1 latency and rebound. Trends Immunol 2023; 44:60-71. [PMID: 36503686 DOI: 10.1016/j.it.2022.11.003] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2022] [Revised: 11/07/2022] [Accepted: 11/09/2022] [Indexed: 12/13/2022]
Abstract
Antiretroviral therapy reduces circulating HIV-1 to undetectable amounts but does not eliminate the virus due to the persistence of a stable reservoir of latently infected cells. The reservoir is maintained both by proliferation of latently infected cells and by reseeding from reactivated cells. A major challenge for the field is to find safe and effective methods to eliminate this source of rebounding HIV-1. Studies on the molecular mechanisms leading to HIV-1 latency and reactivation are being transformed using latency models in primary and patient CD4+ T cells. These studies have revealed the central role played by the biogenesis of the transcription elongation factor P-TEFb (Positive Transcription Elongation Factor b) and its recruitment to proviral HIV-1, for the maintenance of viral latency and the control of viral reactivation.
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Affiliation(s)
- Uri Mbonye
- Department of Molecular Biology and Microbiology, Case Western Reserve University, Cleveland, OH, USA
| | - Fredrick Kizito
- Department of Molecular Biology and Microbiology, Case Western Reserve University, Cleveland, OH, USA
| | - Jonathan Karn
- Department of Molecular Biology and Microbiology, Case Western Reserve University, Cleveland, OH, USA.
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11
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Hsieh E, Janssens DH, Paddison PJ, Browne EP, Henikoff S, OhAinle M, Emerman M. A modular CRISPR screen identifies individual and combination pathways contributing to HIV-1 latency. PLoS Pathog 2023; 19:e1011101. [PMID: 36706161 PMCID: PMC9907829 DOI: 10.1371/journal.ppat.1011101] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2022] [Revised: 02/08/2023] [Accepted: 01/05/2023] [Indexed: 01/28/2023] Open
Abstract
Transcriptional silencing of latent HIV-1 proviruses entails complex and overlapping mechanisms that pose a major barrier to in vivo elimination of HIV-1. We developed a new latency CRISPR screening strategy, called Latency HIV-CRISPR which uses the packaging of guideRNA-encoding lentiviral vector genomes into the supernatant of budding virions as a direct readout of factors involved in the maintenance of HIV-1 latency. We developed a custom guideRNA library targeting epigenetic regulatory genes and paired the screen with and without a latency reversal agent-AZD5582, an activator of the non-canonical NFκB pathway-to examine a combination of mechanisms controlling HIV-1 latency. A component of the Nucleosome Acetyltransferase of H4 histone acetylation (NuA4 HAT) complex, ING3, acts in concert with AZD5582 to activate proviruses in J-Lat cell lines and in a primary CD4+ T cell model of HIV-1 latency. We found that the knockout of ING3 reduces acetylation of the H4 histone tail and BRD4 occupancy on the HIV-1 LTR. However, the combination of ING3 knockout accompanied with the activation of the non-canonical NFκB pathway via AZD5582 resulted in a dramatic increase in initiation and elongation of RNA Polymerase II on the HIV-1 provirus in a manner that is nearly unique among all cellular promoters.
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Affiliation(s)
- Emily Hsieh
- Molecular and Cellular Biology Graduate Program, University of Washington, Seattle, Washington, United States of America
| | - Derek H. Janssens
- Division of Basic Sciences, Fred Hutchinson Cancer Center, Seattle, Washington, United States of America
| | - Patrick J. Paddison
- Division of Human Biology, Fred Hutchinson Cancer Center, Seattle, Washington, United States of America
| | - Edward P. Browne
- Division of Infectious Diseases, Department of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
| | - Steve Henikoff
- Division of Basic Sciences, Fred Hutchinson Cancer Center, Seattle, Washington, United States of America
- Howard Hughes Medical Institute, Chevy Chase, Maryland, United States of America
| | - Molly OhAinle
- Division of Human Biology, Fred Hutchinson Cancer Center, Seattle, Washington, United States of America
| | - Michael Emerman
- Division of Basic Sciences, Fred Hutchinson Cancer Center, Seattle, Washington, United States of America
- Division of Human Biology, Fred Hutchinson Cancer Center, Seattle, Washington, United States of America
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12
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Medicinal Chemistry of Anti-HIV-1 Latency Chemotherapeutics: Biotargets, Binding Modes and Structure-Activity Relationship Investigation. MOLECULES (BASEL, SWITZERLAND) 2022; 28:molecules28010003. [PMID: 36615199 PMCID: PMC9822059 DOI: 10.3390/molecules28010003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/30/2022] [Revised: 12/12/2022] [Accepted: 12/15/2022] [Indexed: 12/24/2022]
Abstract
The existence of latent viral reservoirs (LVRs), also called latent cells, has long been an acknowledged stubborn hurdle for effective treatment of HIV-1/AIDS. This stable and heterogeneous reservoir, which mainly exists in resting memory CD4+ T cells, is not only resistant to highly active antiretroviral therapy (HAART) but cannot be detected by the immune system, leading to rapid drug resistance and viral rebound once antiviral treatment is interrupted. Accordingly, various functional cure strategies have been proposed to combat this barrier, among which one of the widely accepted and utilized protocols is the so-called 'shock-and-kill' regimen. The protocol begins with latency-reversing agents (LRAs), either alone or in combination, to reactivate the latent HIV-1 proviruses, then eliminates them by viral cytopathic mechanisms (e.g., currently available antiviral drugs) or by the immune killing function of the immune system (e.g., NK and CD8+ T cells). In this review, we focuse on the currently explored small molecular LRAs, with emphasis on their mechanism-directed drug targets, binding modes and structure-relationship activity (SAR) profiles, aiming to provide safer and more effective remedies for treating HIV-1 infection.
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13
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Yang X, Zhao X, Zhu Y, Xun J, Wen Q, Pan H, Yang J, Wang J, Liang Z, Shen X, Liang Y, Lin Q, Liang H, Li M, Chen J, Jiang S, Xu J, Lu H, Zhu H. FBXO34 promotes latent HIV-1 activation by post-transcriptional modulation. Emerg Microbes Infect 2022; 11:2785-2799. [PMID: 36285453 PMCID: PMC9665091 DOI: 10.1080/22221751.2022.2140605] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/05/2022]
Abstract
Acquired immunodeficiency syndrome (AIDS) cannot be completely cured, mainly due to the existence of a latent HIV-1 reservoir. However, our current understanding of the molecular mechanisms underlying the establishment and maintenance of HIV-1 latent reservoir is not comprehensive. Here, using a genome-wide CRISPR-Cas9 activation library screening, we identified E3 ubiquitin ligase F-box protein 34 (FBXO34) and the substrate of FBXO34, heterogeneous nuclear ribonucleoprotein U (hnRNP U) was identified by affinity purification mass spectrometry, as new host factors related to HIV-1 latent maintenance. Overexpression of FBXO34 or knockout of hnRNP U can activate latent HIV-1 in multiple latent cell lines. FBXO34 mainly promotes hnRNP U ubiquitination, which leads to hnRNP U degradation and abolishment of the interaction between hnRNP U and HIV-1 mRNA. In a latently infected cell line, hnRNP U interacts with the ReV region of HIV-1 mRNA through amino acids 1-339 to hinder HIV-1 translation, thereby, promoting HIV-1 latency. Importantly, we confirmed the role of the FBXO34/hnRNP U axis in the primary CD4+ T lymphocyte model, and detected differences in hnRNP U expression levels in samples from patients treated with antiretroviral therapy (ART) and healthy people, which further suggests that the FBXO34/hnRNP U axis is a new pathway involved in HIV-1 latency. These results provide mechanistic insights into the critical role of ubiquitination and hnRNP U in HIV-1 latency. This novel FBXO34/hnRNP U axis in HIV transcription may be directly targeted to control HIV reservoirs in patients in the future.
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Affiliation(s)
- Xinyi Yang
- State Key Laboratory of Genetic Engineering and Engineering Research Center of Gene Technology, Ministry of Education, Institute of Genetics, School of Life Sciences, Fudan University, Shanghai 200438, China
| | - Xiaying Zhao
- State Key Laboratory of Genetic Engineering and Engineering Research Center of Gene Technology, Ministry of Education, Institute of Genetics, School of Life Sciences, Fudan University, Shanghai 200438, China
| | - Yuqi Zhu
- State Key Laboratory of Genetic Engineering and Engineering Research Center of Gene Technology, Ministry of Education, Institute of Genetics, School of Life Sciences, Fudan University, Shanghai 200438, China
| | - Jingna Xun
- State Key Laboratory of Genetic Engineering and Engineering Research Center of Gene Technology, Ministry of Education, Institute of Genetics, School of Life Sciences, Fudan University, Shanghai 200438, China
- Scientific Research Center, Shanghai Public Health Clinical Center, Fudan University, Shanghai, China
| | - Qin Wen
- State Key Laboratory of Genetic Engineering and Engineering Research Center of Gene Technology, Ministry of Education, Institute of Genetics, School of Life Sciences, Fudan University, Shanghai 200438, China
| | - Hanyu Pan
- State Key Laboratory of Genetic Engineering and Engineering Research Center of Gene Technology, Ministry of Education, Institute of Genetics, School of Life Sciences, Fudan University, Shanghai 200438, China
| | - Jinlong Yang
- State Key Laboratory of Genetic Engineering and Engineering Research Center of Gene Technology, Ministry of Education, Institute of Genetics, School of Life Sciences, Fudan University, Shanghai 200438, China
| | - Jing Wang
- State Key Laboratory of Genetic Engineering and Engineering Research Center of Gene Technology, Ministry of Education, Institute of Genetics, School of Life Sciences, Fudan University, Shanghai 200438, China
| | - Zhimin Liang
- State Key Laboratory of Genetic Engineering and Engineering Research Center of Gene Technology, Ministry of Education, Institute of Genetics, School of Life Sciences, Fudan University, Shanghai 200438, China
| | - Xiaoting Shen
- State Key Laboratory of Genetic Engineering and Engineering Research Center of Gene Technology, Ministry of Education, Institute of Genetics, School of Life Sciences, Fudan University, Shanghai 200438, China
| | - Yue Liang
- State Key Laboratory of Genetic Engineering and Engineering Research Center of Gene Technology, Ministry of Education, Institute of Genetics, School of Life Sciences, Fudan University, Shanghai 200438, China
| | - Qinru Lin
- State Key Laboratory of Genetic Engineering and Engineering Research Center of Gene Technology, Ministry of Education, Institute of Genetics, School of Life Sciences, Fudan University, Shanghai 200438, China
| | - Huitong Liang
- State Key Laboratory of Genetic Engineering and Engineering Research Center of Gene Technology, Ministry of Education, Institute of Genetics, School of Life Sciences, Fudan University, Shanghai 200438, China
| | - Min Li
- State Key Laboratory of Genetic Engineering and Engineering Research Center of Gene Technology, Ministry of Education, Institute of Genetics, School of Life Sciences, Fudan University, Shanghai 200438, China
| | - Jun Chen
- Scientific Research Center, Shanghai Public Health Clinical Center, Fudan University, Shanghai, China
- Department of Infectious Diseases and Immunology, Shanghai Public Health Clinical Center, Fudan University, Shanghai, China
| | - Shibo Jiang
- Department of Infectious Disease, Key Laboratory of Medical Molecular Virology of Ministry of Education/Health, School of Basic Medical Sciences and Shanghai Public Health Clinical Center, Fudan University, Shanghai, China
| | - Jianqing Xu
- Department of Infectious Disease, Key Laboratory of Medical Molecular Virology of Ministry of Education/Health, School of Basic Medical Sciences and Shanghai Public Health Clinical Center, Fudan University, Shanghai, China
| | - Hongzhou Lu
- Department of Infectious Diseases and Immunology, Shanghai Public Health Clinical Center, Fudan University, Shanghai, China
| | - Huanzhang Zhu
- State Key Laboratory of Genetic Engineering and Engineering Research Center of Gene Technology, Ministry of Education, Institute of Genetics, School of Life Sciences, Fudan University, Shanghai 200438, China
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14
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Scholl A, De S. Epigenetic Regulation by Polycomb Complexes from Drosophila to Human and Its Relation to Communicable Disease Pathogenesis. Int J Mol Sci 2022; 23:ijms232012285. [PMID: 36293135 PMCID: PMC9603650 DOI: 10.3390/ijms232012285] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2022] [Revised: 10/04/2022] [Accepted: 10/10/2022] [Indexed: 12/05/2022] Open
Abstract
Although all cells in the human body are made of the same DNA, these cells undergo differentiation and behave differently during development, through integration of external and internal stimuli via 'specific mechanisms.' Epigenetics is one such mechanism that comprises DNA/RNA, histone modifications, and non-coding RNAs that regulate transcription without changing the genetic code. The discovery of the first Polycomb mutant phenotype in Drosophila started the study of epigenetics more than 80 years ago. Since then, a considerable number of Polycomb Group (PcG) genes in Drosophila have been discovered to be preserved in mammals, including humans. PcG proteins exert their influence through gene repression by acting in complexes, modifying histones, and compacting the chromatin within the nucleus. In this article, we discuss how our knowledge of the PcG repression mechanism in Drosophila translates to human communicable disease research.
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15
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Ren N, Wang F, Zhao L, Wang S, Zhang G, Li J, Zhang B, Wang J, Bergeron E, Yuan Z, Xia H. Efficient rescue of a newly classified Ebinur lake orthobunyavirus with GFP reporter and its application in rapid antiviral screening. Antiviral Res 2022; 207:105421. [PMID: 36150523 DOI: 10.1016/j.antiviral.2022.105421] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2022] [Revised: 08/29/2022] [Accepted: 09/15/2022] [Indexed: 11/30/2022]
Abstract
Orthobunyaviruses have been reported to cause severe diseases in humans or animals, posing a potential threat to human health and socio-economy. Ebinur lake virus (EBIV) is a newly classified orthobunyavirus, which can induce the histopathogenic change and even the high mortality of infected BALB/c mice. Therefore, it is needed to further study the viral replication and pathogenesis, and develop the therapies to cope with its potential infection to human or animals. Here, through the reverse genetics system, the recombinant EBIV of wild type (rEBIV/WT) and NP-conjugated-eGFP (rEBIV/eGFP/S) were rescued for the application of the high-content screening (HCS) of antiviral drug. The eGFP fluorescence signal of the rEBIV/eGFP/S was stable in the process of successive passage in BHK-21 cells (over 10 passages) and this recombinant virus could replicate in various cell lines. Compared to the wild type EBIV, the rEBIV/eGFP/S caused the smaller plaques (diameter around 1 mm on 3 dpi) and lower peak titers (105 PFU/mL), suggesting attenuation due to the eGFP insertion. Through the high-content screening (HCS) system, two antiviral compounds, ribavirin and favipiravir, which previously reported to have effect to some bunyavirus were tested firstly. Ribavirin showed an inhibitory effect on the rEBIV/eGFP/S (EC50 = 14.38 μM) as our expect, while favipiravir with no inhibitory effect even using high doses. Furthermore, Tyrphostin A9 (EC50 = 0.72 μM for rEBIV/eGFP/S, EC50 = 0.05 μM for EBIV-WT) and UNC0638 (EC50 = 1.26 μM for rEBIV/eGFP/S, EC50 = 1.10 μM for rEBIV/eGFP/S) were identified with strong antiviral effect against EBIV in vitro from 150 antiviral compounds. In addition, the time-of-addition assay indicated that Tyrphostin A9 worked in the stage of viral post-infection, and the UNC0638 in all pre-, co-, and post-infection stages. This robust reverse genetics system will facilitate the investigation into the studying of viral replication and assembly mechanisms, and the development of drug and vaccine for EBIV in the future.
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Affiliation(s)
- Nanjie Ren
- Key Laboratory of Special Pathogens and Biosafety, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, Hubei, China; University of Chinese Academy of Sciences, Beijing, China
| | - Fei Wang
- Key Laboratory of Special Pathogens and Biosafety, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, Hubei, China
| | - Lu Zhao
- Institute of Biology, Westlake Institute for Advanced Study, School of Life Sciences, Westlake University, Zhejiang, China
| | - Shunlong Wang
- Key Laboratory of Special Pathogens and Biosafety, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, Hubei, China; University of Chinese Academy of Sciences, Beijing, China
| | - Guilin Zhang
- Xinjiang Heribase Biotechnology CO., LTD., Urumqi, China
| | - Jiaqi Li
- Key Laboratory of Special Pathogens and Biosafety, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, Hubei, China; University of Chinese Academy of Sciences, Beijing, China
| | - Bo Zhang
- Key Laboratory of Special Pathogens and Biosafety, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, Hubei, China; University of Chinese Academy of Sciences, Beijing, China
| | - Jinglin Wang
- Yunnan Tropical and Subtropical Animal Viral Disease Laboratory, Yunnan Animal Science and Veterinary Institute, Kunming, Yunnan, China
| | - Eric Bergeron
- Viral Special Pathogens Branch, Division of High-Consequence Pathogens and Pathology, National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, United States
| | - Zhiming Yuan
- Key Laboratory of Special Pathogens and Biosafety, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, Hubei, China; University of Chinese Academy of Sciences, Beijing, China.
| | - Han Xia
- Key Laboratory of Special Pathogens and Biosafety, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, Hubei, China; University of Chinese Academy of Sciences, Beijing, China.
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16
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Mediouni S, Lyu S, Schader SM, Valente ST. Forging a Functional Cure for HIV: Transcription Regulators and Inhibitors. Viruses 2022; 14:1980. [PMID: 36146786 PMCID: PMC9502519 DOI: 10.3390/v14091980] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2022] [Revised: 08/28/2022] [Accepted: 09/01/2022] [Indexed: 11/16/2022] Open
Abstract
Current antiretroviral therapy (ART) increases the survival of HIV-infected individuals, yet it is not curative. The major barrier to finding a definitive cure for HIV is our inability to identify and eliminate long-lived cells containing the dormant provirus, termed viral reservoir. When ART is interrupted, the viral reservoir ensures heterogenous and stochastic HIV viral gene expression, which can reseed infection back to pre-ART levels. While strategies to permanently eradicate the virus have not yet provided significant success, recent work has focused on the management of this residual viral reservoir to effectively limit comorbidities associated with the ongoing viral transcription still observed during suppressive ART, as well as limit the need for daily ART. Our group has been at the forefront of exploring the viability of the block-and-lock remission approach, focused on the long-lasting epigenetic block of viral transcription such that without daily ART, there is no risk of viral rebound, transmission, or progression to AIDS. Numerous studies have reported inhibitors of both viral and host factors required for HIV transcriptional activation. Here, we highlight and review some of the latest HIV transcriptional inhibitor discoveries that may be leveraged for the clinical exploration of block-and-lock and revolutionize the way we treat HIV infections.
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Affiliation(s)
- Sonia Mediouni
- Department of Immunology and Microbiology, UF Scripps Biomedical Research, 130 Scripps Way, 3C1, Jupiter, FL 33458, USA
| | - Shuang Lyu
- Department of Immunology and Microbiology, UF Scripps Biomedical Research, 130 Scripps Way, 3C1, Jupiter, FL 33458, USA
| | - Susan M. Schader
- Department of Infectious Disease Research, Drug Development Division, Southern Research, 431 Aviation Way, Frederick, MD 21701, USA
| | - Susana T. Valente
- Department of Immunology and Microbiology, UF Scripps Biomedical Research, 130 Scripps Way, 3C1, Jupiter, FL 33458, USA
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17
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Wu L, Pan T, Zhou M, Chen T, Wu S, Lv X, Liu J, Yu F, Guan Y, Liu B, Zhang W, Deng X, Chen Q, Liang A, Lin Y, Wang L, Tang X, Cai W, Li L, He X, Zhang H, Ma X. CBX4 contributes to HIV-1 latency by forming phase-separated nuclear bodies and SUMOylating EZH2. EMBO Rep 2022; 23:e53855. [PMID: 35642598 PMCID: PMC9253744 DOI: 10.15252/embr.202153855] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2021] [Revised: 04/17/2022] [Accepted: 05/18/2022] [Indexed: 09/13/2023] Open
Abstract
The retrovirus HIV-1 integrates into the host genome and establishes a latent viral reservoir that escapes immune surveillance. Molecular mechanisms of HIV-1 latency have been studied extensively to achieve a cure for the acquired immunodeficiency syndrome (AIDS). Latency-reversing agents (LRAs) have been developed to reactivate and eliminate the latent reservoir by the immune system. To develop more promising LRAs, it is essential to evaluate new therapeutic targets. Here, we find that CBX4, a component of the Polycomb Repressive Complex 1 (PRC1), contributes to HIV-1 latency in seven latency models and primary CD4+ T cells. CBX4 forms nuclear bodies with liquid-liquid phase separation (LLPS) properties on the HIV-1 long terminal repeat (LTR) and recruits EZH2, the catalytic subunit of PRC2. CBX4 SUMOylates EZH2 utilizing its SUMO E3 ligase activity, thereby enhancing the H3K27 methyltransferase activity of EZH2. Our results indicate that CBX4 acts as a bridge between the repressor complexes PRC1 and PRC2 that act synergistically to maintain HIV-1 latency. Dissolution of phase-separated CBX4 bodies could be a potential intervention to reactivate latent HIV-1.
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Affiliation(s)
- Liyang Wu
- Institute of Human VirologyKey Laboratory of Tropical Disease Control of Ministry EducationGuangdong Engineering Research Center for Antimicrobial Agent and ImmunotechnologyZhongshan School of MedicineSun Yat‐sen UniversityGuangzhouChina
| | - Ting Pan
- Institute of Human VirologyKey Laboratory of Tropical Disease Control of Ministry EducationGuangdong Engineering Research Center for Antimicrobial Agent and ImmunotechnologyZhongshan School of MedicineSun Yat‐sen UniversityGuangzhouChina
- Center for Infection and Immunity StudySchool of MedicineSun Yat‐sen UniversityShenzhenChina
| | - Mo Zhou
- Institute of Human VirologyKey Laboratory of Tropical Disease Control of Ministry EducationGuangdong Engineering Research Center for Antimicrobial Agent and ImmunotechnologyZhongshan School of MedicineSun Yat‐sen UniversityGuangzhouChina
| | - Tao Chen
- Institute of Human VirologyKey Laboratory of Tropical Disease Control of Ministry EducationGuangdong Engineering Research Center for Antimicrobial Agent and ImmunotechnologyZhongshan School of MedicineSun Yat‐sen UniversityGuangzhouChina
| | - Shiyu Wu
- Institute of Human VirologyKey Laboratory of Tropical Disease Control of Ministry EducationGuangdong Engineering Research Center for Antimicrobial Agent and ImmunotechnologyZhongshan School of MedicineSun Yat‐sen UniversityGuangzhouChina
| | - Xi Lv
- Guangdong Provincial People's HospitalGuangdong Academy of Medical SciencesGuangzhouChina
| | - Jun Liu
- Institute of Human VirologyKey Laboratory of Tropical Disease Control of Ministry EducationGuangdong Engineering Research Center for Antimicrobial Agent and ImmunotechnologyZhongshan School of MedicineSun Yat‐sen UniversityGuangzhouChina
| | - Fei Yu
- Guangdong Provincial People's HospitalGuangdong Academy of Medical SciencesGuangzhouChina
| | - Yuanjun Guan
- Core Laboratory Platform for Medical ScienceZhongshan School of MedicineSun Yat‐sen UniversityGuangzhouChina
| | - Bingfeng Liu
- Institute of Human VirologyKey Laboratory of Tropical Disease Control of Ministry EducationGuangdong Engineering Research Center for Antimicrobial Agent and ImmunotechnologyZhongshan School of MedicineSun Yat‐sen UniversityGuangzhouChina
| | - Wanying Zhang
- Institute of Human VirologyKey Laboratory of Tropical Disease Control of Ministry EducationGuangdong Engineering Research Center for Antimicrobial Agent and ImmunotechnologyZhongshan School of MedicineSun Yat‐sen UniversityGuangzhouChina
| | - Xiaohui Deng
- Center for Infection and Immunity StudySchool of MedicineSun Yat‐sen UniversityShenzhenChina
| | - Qianyu Chen
- Guangdong Provincial People's HospitalGuangdong Academy of Medical SciencesGuangzhouChina
| | - Anqi Liang
- Guangdong Provincial People's HospitalGuangdong Academy of Medical SciencesGuangzhouChina
| | - Yingtong Lin
- Institute of Human VirologyKey Laboratory of Tropical Disease Control of Ministry EducationGuangdong Engineering Research Center for Antimicrobial Agent and ImmunotechnologyZhongshan School of MedicineSun Yat‐sen UniversityGuangzhouChina
| | | | - Xiaoping Tang
- Department of Infectious DiseasesGuangzhou 8 People's HospitalGuangzhouChina
| | - Weiping Cai
- Department of Infectious DiseasesGuangzhou 8 People's HospitalGuangzhouChina
| | - Linghua Li
- Department of Infectious DiseasesGuangzhou 8 People's HospitalGuangzhouChina
| | - Xin He
- Institute of Human VirologyKey Laboratory of Tropical Disease Control of Ministry EducationGuangdong Engineering Research Center for Antimicrobial Agent and ImmunotechnologyZhongshan School of MedicineSun Yat‐sen UniversityGuangzhouChina
| | - Hui Zhang
- Institute of Human VirologyKey Laboratory of Tropical Disease Control of Ministry EducationGuangdong Engineering Research Center for Antimicrobial Agent and ImmunotechnologyZhongshan School of MedicineSun Yat‐sen UniversityGuangzhouChina
- Guangzhou LaboratoryGuangzhou International Bio‐IslandGuangzhouChina
| | - Xiancai Ma
- Institute of Human VirologyKey Laboratory of Tropical Disease Control of Ministry EducationGuangdong Engineering Research Center for Antimicrobial Agent and ImmunotechnologyZhongshan School of MedicineSun Yat‐sen UniversityGuangzhouChina
- Guangdong Provincial People's HospitalGuangdong Academy of Medical SciencesGuangzhouChina
- Guangzhou LaboratoryGuangzhou International Bio‐IslandGuangzhouChina
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18
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Ding J, Wang S, Wang Z, Chen S, Zhao J, Solomon M, Liu Z, Guo F, Ma L, Wen J, Li X, Liang C, Cen S. Schlafen 5 suppresses human immunodeficiency virus type 1 transcription by commandeering cellular epigenetic machinery. Nucleic Acids Res 2022; 50:6137-6153. [PMID: 35687115 PMCID: PMC9226525 DOI: 10.1093/nar/gkac489] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2022] [Revised: 05/17/2022] [Accepted: 05/26/2022] [Indexed: 11/14/2022] Open
Abstract
Schlafen-5 (SLFN5) is an interferon-induced protein of the Schlafen family, which are involved in immune responses and oncogenesis. To date, little is known regarding its anti-HIV-1 function. Here, the authors report that overexpression of SLFN5 inhibits HIV-1 replication and reduces viral mRNA levels, whereas depletion of endogenous SLFN5 promotes HIV-1 replication. Moreover, they show that SLFN5 markedly decreases the transcriptional activity of HIV-1 long terminal repeat (LTR) via binding to two sequences in the U5-R region, which consequently represses the recruitment of RNA polymerase II to the transcription initiation site. Mutagenesis studies show the importance of nuclear localization and the N-terminal 1-570 amino acids fragment in the inhibition of HIV-1. Further mechanistic studies demonstrate that SLFN5 interacts with components of the PRC2 complex, G9a and Histone H3, thereby promoting H3K27me2 and H3K27me3 modification leading to silencing HIV-1 transcription. In concert with this, they find that SLFN5 blocks the activation of latent HIV-1. Altogether, their findings demonstrate that SLFN5 is a transcriptional repressor of HIV-1 through epigenetic modulation and a potential determinant of HIV-1 latency.
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Affiliation(s)
- Jiwei Ding
- Institute of Medicinal Biotechnology, Chinese Academy of Medical Science, Beijing, China
| | - Shujie Wang
- Institute of Medicinal Biotechnology, Chinese Academy of Medical Science, Beijing, China
| | - Zhen Wang
- Lady Davis Institute for Medical Research and McGill AIDS Centre, Jewish General Hospital, Montreal, Quebec, Canada
| | - Shumin Chen
- Institute of Medicinal Biotechnology, Chinese Academy of Medical Science, Beijing, China
| | - Jianyuan Zhao
- Institute of Medicinal Biotechnology, Chinese Academy of Medical Science, Beijing, China
| | - Magan Solomon
- Lady Davis Institute for Medical Research and McGill AIDS Centre, Jewish General Hospital, Montreal, Quebec, Canada
| | - Zhenlong Liu
- Lady Davis Institute for Medical Research and McGill AIDS Centre, Jewish General Hospital, Montreal, Quebec, Canada
| | - Fei Guo
- Institute of Pathogen Biology, Chinese Academy of Medical Science, Beijing, China
| | - Ling Ma
- Institute of Medicinal Biotechnology, Chinese Academy of Medical Science, Beijing, China
| | - Jiajia Wen
- Institute of Medicinal Biotechnology, Chinese Academy of Medical Science, Beijing, China
| | - Xiaoyu Li
- Institute of Medicinal Biotechnology, Chinese Academy of Medical Science, Beijing, China
| | - Chen Liang
- Lady Davis Institute for Medical Research and McGill AIDS Centre, Jewish General Hospital, Montreal, Quebec, Canada
| | - Shan Cen
- Institute of Medicinal Biotechnology, Chinese Academy of Medical Science, Beijing, China.,CAMS Key Laboratory of Antiviral Drug Research, Chinese Academy of Medical Science, Beijing, China
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19
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Ne E, Crespo R, Izquierdo-Lara R, Rao S, Koçer S, Górska A, van Staveren T, Kan TW, van de Vijver D, Dekkers D, Rokx C, Moulos P, Hatzis P, Palstra RJ, Demmers J, Mahmoudi T. Catchet-MS identifies IKZF1-targeting thalidomide analogues as novel HIV-1 latency reversal agents. Nucleic Acids Res 2022; 50:5577-5598. [PMID: 35640596 PMCID: PMC9177988 DOI: 10.1093/nar/gkac407] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2021] [Revised: 04/11/2022] [Accepted: 05/24/2022] [Indexed: 12/27/2022] Open
Abstract
A major pharmacological strategy toward HIV cure aims to reverse latency in infected cells as a first step leading to their elimination. While the unbiased identification of molecular targets physically associated with the latent HIV-1 provirus would be highly valuable to unravel the molecular determinants of HIV-1 transcriptional repression and latency reversal, due to technical limitations, this has been challenging. Here we use a dCas9 targeted chromatin and histone enrichment strategy coupled to mass spectrometry (Catchet-MS) to probe the differential protein composition of the latent and activated HIV-1 5′LTR. Catchet-MS identified known and novel latent 5′LTR-associated host factors. Among these, IKZF1 is a novel HIV-1 transcriptional repressor, required for Polycomb Repressive Complex 2 recruitment to the LTR. We find the clinically advanced thalidomide analogue iberdomide, and the FDA approved analogues lenalidomide and pomalidomide, to be novel LRAs. We demonstrate that, by targeting IKZF1 for degradation, these compounds reverse HIV-1 latency in CD4+ T-cells isolated from virally suppressed people living with HIV-1 and that they are able to synergize with other known LRAs.
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Affiliation(s)
- Enrico Ne
- Department of Biochemistry, Erasmus University Medical Center, Ee622 PO Box 2040, 3000CA Rotterdam, The Netherlands
| | - Raquel Crespo
- Department of Biochemistry, Erasmus University Medical Center, Ee622 PO Box 2040, 3000CA Rotterdam, The Netherlands
| | - Ray Izquierdo-Lara
- Department of Biochemistry, Erasmus University Medical Center, Ee622 PO Box 2040, 3000CA Rotterdam, The Netherlands
| | - Shringar Rao
- Department of Biochemistry, Erasmus University Medical Center, Ee622 PO Box 2040, 3000CA Rotterdam, The Netherlands
| | - Selin Koçer
- Department of Biochemistry, Erasmus University Medical Center, Ee622 PO Box 2040, 3000CA Rotterdam, The Netherlands
| | - Alicja Górska
- Department of Biochemistry, Erasmus University Medical Center, Ee622 PO Box 2040, 3000CA Rotterdam, The Netherlands
| | - Thomas van Staveren
- Department of Biochemistry, Erasmus University Medical Center, Ee622 PO Box 2040, 3000CA Rotterdam, The Netherlands
| | - Tsung Wai Kan
- Department of Biochemistry, Erasmus University Medical Center, Ee622 PO Box 2040, 3000CA Rotterdam, The Netherlands.,Department of Pathology, Erasmus University Medical Center, The Netherlands.,Department of Urology, Erasmus University Medical Center, The Netherlands
| | - David van de Vijver
- Department of Viroscience, Erasmus University Medical Center, The Netherlands
| | - Dick Dekkers
- Proteomics Center, Erasmus University Medical Center, Ee679a PO Box 2040, 3000CA Rotterdam, The Netherlands
| | - Casper Rokx
- Department of Internal Medicine, Section of Infectious Diseases, Erasmus University Medical Center, Rg-530, PO Box 2040, 3000CA Rotterdam, The Netherlands
| | - Panagiotis Moulos
- Institute for Fundamental Biomedical Research, Biomedical Sciences Research Center "Alexander Fleming", 16672, Vari, Greece
| | - Pantelis Hatzis
- Institute for Fundamental Biomedical Research, Biomedical Sciences Research Center "Alexander Fleming", 16672, Vari, Greece
| | - Robert-Jan Palstra
- Department of Biochemistry, Erasmus University Medical Center, Ee622 PO Box 2040, 3000CA Rotterdam, The Netherlands.,Department of Pathology, Erasmus University Medical Center, The Netherlands.,Department of Urology, Erasmus University Medical Center, The Netherlands
| | - Jeroen Demmers
- Proteomics Center, Erasmus University Medical Center, Ee679a PO Box 2040, 3000CA Rotterdam, The Netherlands
| | - Tokameh Mahmoudi
- Department of Biochemistry, Erasmus University Medical Center, Ee622 PO Box 2040, 3000CA Rotterdam, The Netherlands.,Department of Pathology, Erasmus University Medical Center, The Netherlands.,Department of Urology, Erasmus University Medical Center, The Netherlands
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20
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Falcinelli SD, Peterson JJ, Turner AMW, Irlbeck D, Read J, Raines SL, James KS, Sutton C, Sanchez A, Emery A, Sampey G, Ferris R, Allard B, Ghofrani S, Kirchherr JL, Baker C, Kuruc JD, Gay CL, James LI, Wu G, Zuck P, Rioja I, Furze RC, Prinjha RK, Howell BJ, Swanstrom R, Browne EP, Strahl BD, Dunham RM, Archin NM, Margolis DM. Combined noncanonical NF-κB agonism and targeted BET bromodomain inhibition reverse HIV latency ex vivo. J Clin Invest 2022; 132:e157281. [PMID: 35426377 PMCID: PMC9012286 DOI: 10.1172/jci157281] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2021] [Accepted: 03/01/2022] [Indexed: 11/23/2022] Open
Abstract
Latency reversal strategies for HIV cure using inhibitor of apoptosis protein (IAP) antagonists (IAPi) induce unprecedented levels of latent reservoir expression without immunotoxicity during suppressive antiretroviral therapy (ART). However, full targeting of the reservoir may require combinatorial approaches. A Jurkat latency model screen for IAPi combination partners demonstrated synergistic latency reversal with bromodomain (BD) and extraterminal domain protein inhibitors (BETi). Mechanistic investigations using CRISPR-CAS9 and single-cell RNA-Seq informed comprehensive ex vivo evaluations of IAPi plus pan-BET, bD-selective BET, or selective BET isoform targeting in CD4+ T cells from ART-suppressed donors. IAPi+BETi treatment resulted in striking induction of cell-associated HIV gag RNA, but lesser induction of fully elongated and tat-rev RNA compared with T cell activation-positive controls. IAPi+BETi resulted in HIV protein induction in bulk cultures of CD4+ T cells using an ultrasensitive p24 assay, but did not result in enhanced viral outgrowth frequency using a standard quantitative viral outgrowth assay. This study defines HIV transcriptional elongation and splicing as important barriers to latent HIV protein expression following latency reversal, delineates the roles of BET proteins and their BDs in HIV latency, and provides a rationale for exploration of IAPi+BETi in animal models of HIV latency.
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Affiliation(s)
- Shane D. Falcinelli
- UNC HIV Cure Center, University of North Carolina (UNC), Chapel Hill, North Carolina, USA
- Department of Microbiology and Immunology, UNC School of Medicine, Chapel Hill, North Carolina, USA
| | - Jackson J. Peterson
- UNC HIV Cure Center, University of North Carolina (UNC), Chapel Hill, North Carolina, USA
- Department of Microbiology and Immunology, UNC School of Medicine, Chapel Hill, North Carolina, USA
| | - Anne-Marie W. Turner
- UNC HIV Cure Center, University of North Carolina (UNC), Chapel Hill, North Carolina, USA
- Division of Infectious Diseases, Department of Medicine, UNC, Chapel Hill, North Carolina, USA
| | - David Irlbeck
- UNC HIV Cure Center, University of North Carolina (UNC), Chapel Hill, North Carolina, USA
- HIV Drug Discovery, ViiV Healthcare, Research Triangle Park, North Carolina, USA
| | - Jenna Read
- UNC HIV Cure Center, University of North Carolina (UNC), Chapel Hill, North Carolina, USA
| | - Samuel L.M. Raines
- UNC HIV Cure Center, University of North Carolina (UNC), Chapel Hill, North Carolina, USA
| | - Katherine S. James
- UNC HIV Cure Center, University of North Carolina (UNC), Chapel Hill, North Carolina, USA
| | - Cameron Sutton
- UNC HIV Cure Center, University of North Carolina (UNC), Chapel Hill, North Carolina, USA
- Department of Biochemistry and Biophysics, UNC School of Medicine, Chapel Hill, North Carolina, USA
| | - Anthony Sanchez
- UNC HIV Cure Center, University of North Carolina (UNC), Chapel Hill, North Carolina, USA
| | - Ann Emery
- UNC HIV Cure Center, University of North Carolina (UNC), Chapel Hill, North Carolina, USA
- Department of Biochemistry and Biophysics, UNC School of Medicine, Chapel Hill, North Carolina, USA
| | - Gavin Sampey
- UNC HIV Cure Center, University of North Carolina (UNC), Chapel Hill, North Carolina, USA
| | - Robert Ferris
- UNC HIV Cure Center, University of North Carolina (UNC), Chapel Hill, North Carolina, USA
- HIV Drug Discovery, ViiV Healthcare, Research Triangle Park, North Carolina, USA
| | - Brigitte Allard
- UNC HIV Cure Center, University of North Carolina (UNC), Chapel Hill, North Carolina, USA
| | - Simon Ghofrani
- UNC HIV Cure Center, University of North Carolina (UNC), Chapel Hill, North Carolina, USA
| | - Jennifer L. Kirchherr
- UNC HIV Cure Center, University of North Carolina (UNC), Chapel Hill, North Carolina, USA
| | - Caroline Baker
- Division of Infectious Diseases, Department of Medicine, UNC, Chapel Hill, North Carolina, USA
| | - JoAnn D. Kuruc
- UNC HIV Cure Center, University of North Carolina (UNC), Chapel Hill, North Carolina, USA
- Division of Infectious Diseases, Department of Medicine, UNC, Chapel Hill, North Carolina, USA
| | - Cynthia L. Gay
- UNC HIV Cure Center, University of North Carolina (UNC), Chapel Hill, North Carolina, USA
- Division of Infectious Diseases, Department of Medicine, UNC, Chapel Hill, North Carolina, USA
| | - Lindsey I. James
- UNC HIV Cure Center, University of North Carolina (UNC), Chapel Hill, North Carolina, USA
- Division of Chemical Biology and Medicinal Chemistry, UNC Eshelman School of Pharmacy, Chapel Hill, North Carolina, USA
| | - Guoxin Wu
- Department of Infectious Disease, Merck & Co. Inc., Kenilworth, New Jersey, USA
| | - Paul Zuck
- Department of Infectious Disease, Merck & Co. Inc., Kenilworth, New Jersey, USA
| | - Inmaculada Rioja
- Immuno-Epigenetics, Immunology Research Unit, GSK Medicines Research Centre, Stevenage, United Kingdom
| | - Rebecca C. Furze
- Immuno-Epigenetics, Immunology Research Unit, GSK Medicines Research Centre, Stevenage, United Kingdom
| | - Rab K. Prinjha
- Immuno-Epigenetics, Immunology Research Unit, GSK Medicines Research Centre, Stevenage, United Kingdom
| | - Bonnie J. Howell
- Department of Infectious Disease, Merck & Co. Inc., Kenilworth, New Jersey, USA
| | - Ronald Swanstrom
- UNC HIV Cure Center, University of North Carolina (UNC), Chapel Hill, North Carolina, USA
- Department of Biochemistry and Biophysics, UNC School of Medicine, Chapel Hill, North Carolina, USA
| | - Edward P. Browne
- UNC HIV Cure Center, University of North Carolina (UNC), Chapel Hill, North Carolina, USA
- Department of Microbiology and Immunology, UNC School of Medicine, Chapel Hill, North Carolina, USA
- Division of Infectious Diseases, Department of Medicine, UNC, Chapel Hill, North Carolina, USA
| | - Brian D. Strahl
- UNC HIV Cure Center, University of North Carolina (UNC), Chapel Hill, North Carolina, USA
- Department of Biochemistry and Biophysics, UNC School of Medicine, Chapel Hill, North Carolina, USA
| | - Richard M. Dunham
- UNC HIV Cure Center, University of North Carolina (UNC), Chapel Hill, North Carolina, USA
- HIV Drug Discovery, ViiV Healthcare, Research Triangle Park, North Carolina, USA
| | - Nancie M. Archin
- UNC HIV Cure Center, University of North Carolina (UNC), Chapel Hill, North Carolina, USA
- Division of Infectious Diseases, Department of Medicine, UNC, Chapel Hill, North Carolina, USA
| | - David M. Margolis
- UNC HIV Cure Center, University of North Carolina (UNC), Chapel Hill, North Carolina, USA
- Department of Microbiology and Immunology, UNC School of Medicine, Chapel Hill, North Carolina, USA
- Division of Infectious Diseases, Department of Medicine, UNC, Chapel Hill, North Carolina, USA
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21
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Miller JS, Davis ZB, Helgeson E, Reilly C, Thorkelson A, Anderson J, Lima NS, Jorstad S, Hart GT, Lee JH, Safrit JT, Wong H, Cooley S, Gharu L, Chung H, Soon-Shiong P, Dobrowolski C, Fletcher CV, Karn J, Douek DC, Schacker TW. Safety and virologic impact of the IL-15 superagonist N-803 in people living with HIV: a phase 1 trial. Nat Med 2022; 28:392-400. [DOI: 10.1038/s41591-021-01651-9] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2020] [Accepted: 11/30/2021] [Indexed: 12/26/2022]
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22
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Joussef-Piña S, Nankya I, Nalukwago S, Baseke J, Rwambuya S, Winner D, Kyeyune F, Chervenak K, Thiel B, Asaad R, Dobrowolski C, Luttge B, Lawley B, Kityo CM, Boom WH, Karn J, Quiñones-Mateu ME. Reduced and highly diverse peripheral HIV-1 reservoir in virally suppressed patients infected with non-B HIV-1 strains in Uganda. Retrovirology 2022; 19:1. [PMID: 35033105 PMCID: PMC8760765 DOI: 10.1186/s12977-022-00587-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2021] [Accepted: 01/03/2022] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Our understanding of the peripheral human immunodeficiency virus type 1 (HIV-1) reservoir is strongly biased towards subtype B HIV-1 strains, with only limited information available from patients infected with non-B HIV-1 subtypes, which are the predominant viruses seen in low- and middle-income countries (LMIC) in Africa and Asia. RESULTS In this study, blood samples were obtained from well-suppressed ART-experienced HIV-1 patients monitored in Uganda (n = 62) or the U.S. (n = 50), with plasma HIV-1 loads < 50 copies/ml and CD4+ T-cell counts > 300 cells/ml. The peripheral HIV-1 reservoir, i.e., cell-associated HIV-1 RNA and proviral DNA, was characterized using our novel deep sequencing-based EDITS assay. Ugandan patients were slightly younger (median age 43 vs 49 years) and had slightly lower CD4+ counts (508 vs 772 cells/ml) than U.S. individuals. All Ugandan patients were infected with non-B HIV-1 subtypes (31% A1, 64% D, or 5% C), while all U.S. individuals were infected with subtype B viruses. Unexpectedly, we observed a significantly larger peripheral inducible HIV-1 reservoir in U.S. patients compared to Ugandan individuals (48 vs. 11 cell equivalents/million cells, p < 0.0001). This divergence in reservoir size was verified measuring proviral DNA (206 vs. 88 cell equivalents/million cells, p < 0.0001). However, the peripheral HIV-1 reservoir was more diverse in Ugandan than in U.S. individuals (8.6 vs. 4.7 p-distance, p < 0.0001). CONCLUSIONS The smaller, but more diverse, peripheral HIV-1 reservoir in Ugandan patients might be associated with viral (e.g., non-B subtype with higher cytopathicity) and/or host (e.g., higher incidence of co-infections or co-morbidities leading to less clonal expansion) factors. This highlights the need to understand reservoir dynamics in diverse populations as part of ongoing efforts to find a functional cure for HIV-1 infection in LMICs.
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Affiliation(s)
- Samira Joussef-Piña
- Departments of Molecular Biology and Microbiology, Case Western Reserve University, Cleveland, OH, USA
| | - Immaculate Nankya
- Center for AIDS Research Uganda Laboratories, Joint Clinical Research Centre, Kampala, Uganda
| | - Sophie Nalukwago
- Center for AIDS Research Uganda Laboratories, Joint Clinical Research Centre, Kampala, Uganda
| | - Joy Baseke
- Center for AIDS Research Uganda Laboratories, Joint Clinical Research Centre, Kampala, Uganda
| | - Sandra Rwambuya
- Center for AIDS Research Uganda Laboratories, Joint Clinical Research Centre, Kampala, Uganda
| | - Dane Winner
- Departments of Molecular Biology and Microbiology, Case Western Reserve University, Cleveland, OH, USA
| | - Fred Kyeyune
- Center for AIDS Research Uganda Laboratories, Joint Clinical Research Centre, Kampala, Uganda
| | - Keith Chervenak
- Departments of Medicine, Case Western Reserve University, Cleveland, OH, USA
| | - Bonnie Thiel
- Departments of Medicine, Case Western Reserve University, Cleveland, OH, USA
| | - Robert Asaad
- Departments of Medicine, Case Western Reserve University, Cleveland, OH, USA
| | - Curtis Dobrowolski
- Departments of Molecular Biology and Microbiology, Case Western Reserve University, Cleveland, OH, USA
| | - Benjamin Luttge
- Departments of Molecular Biology and Microbiology, Case Western Reserve University, Cleveland, OH, USA
| | - Blair Lawley
- Department of Microbiology and Immunology, School of Biomedical Sciences, University of Otago, 720 Cumberland Street, P.O. Box 56, Dunedin, New Zealand
| | - Cissy M Kityo
- Center for AIDS Research Uganda Laboratories, Joint Clinical Research Centre, Kampala, Uganda
| | - W Henry Boom
- Center for AIDS Research Uganda Laboratories, Joint Clinical Research Centre, Kampala, Uganda
- Departments of Medicine, Case Western Reserve University, Cleveland, OH, USA
| | - Jonathan Karn
- Departments of Molecular Biology and Microbiology, Case Western Reserve University, Cleveland, OH, USA
- Center for AIDS Research Uganda Laboratories, Joint Clinical Research Centre, Kampala, Uganda
| | - Miguel E Quiñones-Mateu
- Center for AIDS Research Uganda Laboratories, Joint Clinical Research Centre, Kampala, Uganda.
- Department of Microbiology and Immunology, School of Biomedical Sciences, University of Otago, 720 Cumberland Street, P.O. Box 56, Dunedin, New Zealand.
- Webster Centre for Infectious Diseases, University of Otago, Dunedin, New Zealand.
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23
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Margolis DM. Latency Reversal and Clearance of Persistent HIV Infection. Methods Mol Biol 2022; 2407:375-389. [PMID: 34985677 DOI: 10.1007/978-1-0716-1871-4_25] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Efforts to prevent and treat human immunodeficiency virus type 1 (HIV) infection have begun to blunt the spread of HIV infection. Potent, safe, and well-tolerated antiretroviral therapy (ART) allows those infected with HIV to attain a life expectancy similar to that of HIV-uninfected individuals. But the persistence of the quiescent retroviral genome, enforced by the natural proliferative responses of the immune system itself, and a delicate balance of regulators viral expression, mandates lifelong ART suppression to prevent rebound viremia and the return of disease.The approach to HIV eradication that has been studied the most extensively envisions adding therapies to induce the expression of quiescent HIV-1 genomes following the control of viremia by ART, paired with immunotherapies to clear persistent infection. Paired testing of latency reversal and clearance strategies has begun, but the field is still in its infancy and additional obstacles to HIV eradication may emerge. However, there is reason for optimism that together with advances in ART delivery and HIV prevention strategies, efforts in HIV cure research will markedly diminish the effect of the HIV pandemic on society.
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Affiliation(s)
- David M Margolis
- UNC HIV Cure Center, Department of Medicine, and Microbiology and Immunology, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, NC, USA.
- Department of Epidemiology, University of North Carolina at Chapel Hill School of Public Health, Chapel Hill, NC, USA.
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24
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A Reliable Primary Cell Model for HIV Latency: The QUECEL (Quiescent Effector Cell Latency) Method. Methods Mol Biol 2022; 2407:57-68. [PMID: 34985657 DOI: 10.1007/978-1-0716-1871-4_5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
One of the main methods to generate the HIV reservoir is during the transition of infected activated effector CD4 T cells to a memory phenotype. The QUECEL (Quiescent Effector Cell Latency) protocol mimics this process efficiently and allows for production of large numbers of latently infected CD4+ T cells. After polarization and expansion, CD4+ T cells are infected with a single round reporter virus which expressed GFP/CD8a. The infected cells are purified and coerced into quiescence using a defined cocktail of cytokines including TGF-β, IL-10, and IL-8, producing a homogeneous population of latently infected cells. Since homogeneous populations of latently infected cells can be recovered, the QUECEL model has an excellent signal-to-noise ratio, and has been extremely consistent and reproducible in numerous experiments performed during the last 5 years. The ease, efficiency, and accurate mimicking of physiological conditions make the QUECEL model a robust and reproducible tool to study the molecular mechanisms underlying HIV latency.
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25
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Bosque A. The Cultured T CM Model of HIV Latency. Methods Mol Biol 2022; 2407:45-55. [PMID: 34985656 DOI: 10.1007/978-1-0716-1871-4_4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Models to study HIV latency have improved our understanding of the mechanisms involved in this process and have helped in the discovery and development of therapeutic strategies to eradicate HIV. Primary cell models are based on the in vitro generation of latently infected cells using CD4T cells isolated from blood, lymph nodes or other lymphoid organs. In this chapter, we describe the generation of HIV latently infected memory CD4T cells using blood naïve CD4T cells from peripheral blood with a phenotype resembling that of central memory CD4T cells. This model can be used to investigate the mechanisms involved in latency as well to develop strategies to target it.
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Affiliation(s)
- Alberto Bosque
- Department of Microbiology, Immunology and Tropical Medicine, George Washington University, Washington, DC, USA.
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26
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Yang X, Huang T, Wang T, Gao H, Zhang H, Peng W, Zhao J, Hu S, Lu P, Hong Z, Li B, Deng K. MAT2A-Mediated S-Adenosylmethionine Level in CD4 + T Cells Regulates HIV-1 Latent Infection. Front Immunol 2021; 12:745784. [PMID: 34616406 PMCID: PMC8488394 DOI: 10.3389/fimmu.2021.745784] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2021] [Accepted: 08/26/2021] [Indexed: 12/02/2022] Open
Abstract
Antiretroviral drugs effectively halt HIV-1 replication and disease progression, however, due to the presence of a stable viral latent reservoir, the infection cannot be cured by antiretroviral drugs alone. Elucidating the molecular mechanisms underlying HIV-1 latent infection remains a critical hurdle that precludes the development of novel therapeutic strategies aiming for a potential functional cure. Cellular metabolism has been reported to affect HIV-1 replication in CD4+ T cells, but it remains largely unclear whether it is involved in the regulation of HIV-1 latency. Here, we performed a sub-pooled CRISPR library knockout screen targeting 1773 metabolic-related genes in a cell model of HIV-1 latent infection and found that Methionine Adenosyltransferase 2A (MAT2A) contributes to HIV-1 latency. MAT2A knockout enhanced the reactivation of latent HIV-1 while MAT2A overexpression did the opposite. Mechanistically, MAT2A modulates HIV-1 latency through S-Adenosylmethionine (SAM)-mediated one-carbon flux. MAT2A knockout resulted in a significant downregulation of DNA and histone methylation at the HIV-1 5’-LTR. Importantly, we found that the plasma level of SAM is positively correlated with HIV-1 DNA in PBMCs from ART-treated infected individuals, suggesting SAM could serve as a potential biomarker for the latent viral reservoir. Overall, this study reveals an important role of MAT2A-mediated one-carbon metabolism in regulating HIV-1 latency and provides a promising target for the development of new strategies for a functional cure of HIV-1.
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Affiliation(s)
- Xiaofan Yang
- Institute of Human Virology, Key Laboratory of Tropical Disease Control of Ministry of Education, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China.,Department of Immunology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China
| | - Ting Huang
- Institute of Human Virology, Key Laboratory of Tropical Disease Control of Ministry of Education, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China.,School of Medicine, Sun Yat-sen University, Shenzhen, China
| | - Tiantian Wang
- Institute of Human Virology, Key Laboratory of Tropical Disease Control of Ministry of Education, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China.,Department of Immunology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China
| | - Hongbo Gao
- Institute of Human Virology, Key Laboratory of Tropical Disease Control of Ministry of Education, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China.,Department of Immunology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China
| | - Haitao Zhang
- Department of Infectious Diseases, Fifth Affiliated Hospital, Sun Yat-sen University, Zhuhai, China
| | - Wen Peng
- Institute of Human Virology, Key Laboratory of Tropical Disease Control of Ministry of Education, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China.,Department of Immunology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China
| | - Jiacong Zhao
- Institute of Human Virology, Key Laboratory of Tropical Disease Control of Ministry of Education, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China.,Department of Immunology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China
| | - Shujing Hu
- Institute of Human Virology, Key Laboratory of Tropical Disease Control of Ministry of Education, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China.,Department of Immunology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China
| | - Panpan Lu
- School of Medicine, Sun Yat-sen University, Shenzhen, China
| | - Zhongsi Hong
- Department of Infectious Diseases, Fifth Affiliated Hospital, Sun Yat-sen University, Zhuhai, China
| | - Bo Li
- Department of Biochemistry, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China
| | - Kai Deng
- Institute of Human Virology, Key Laboratory of Tropical Disease Control of Ministry of Education, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China.,Department of Immunology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China
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27
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Nguyen K, Dobrowolski C, Shukla M, Cho WK, Luttge B, Karn J. Inhibition of the H3K27 demethylase UTX enhances the epigenetic silencing of HIV proviruses and induces HIV-1 DNA hypermethylation but fails to permanently block HIV reactivation. PLoS Pathog 2021; 17:e1010014. [PMID: 34673825 PMCID: PMC8562785 DOI: 10.1371/journal.ppat.1010014] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2021] [Revised: 11/02/2021] [Accepted: 10/07/2021] [Indexed: 01/09/2023] Open
Abstract
One strategy for a functional cure of HIV-1 is "block and lock", which seeks to permanently suppress the rebound of quiescent HIV-1 by epigenetic silencing. For the bivalent promoter in the HIV LTR, both histone 3 lysine 27 tri-methylation (H3K27me3) and DNA methylation are associated with viral suppression, while H3K4 tri-methylation (H3K4me3) is correlated with viral expression. However, H3K27me3 is readily reversed upon activation of T-cells through the T-cell receptor. In an attempt to suppress latent HIV-1 in a stable fashion, we knocked down the expression or inhibited the activity of UTX/KDM6A, the major H3K27 demethylase, and investigated its impact on latent HIV-1 reactivation in T cells. Inhibition of UTX dramatically enhanced H3K27me3 levels at the HIV LTR and was associated with increased DNA methylation. In latently infected cells from patients, GSK-J4, which is a potent dual inhibitor of the H3K27me3/me2-demethylases JMJD3/KDM6B and UTX/KDM6A, effectively suppressed the reactivation of latent HIV-1 and also induced DNA methylation at specific sites in the 5'LTR of latent HIV-1 by the enhanced recruitment of DNMT3A to HIV-1. Nonetheless, suppression of HIV-1 through epigenetic silencing required the continued treatment with GSK-J4 and was rapidly reversed after removal of the drug. DNA methylation was also rapidly lost after removal of drug, suggesting active and rapid DNA-demethylation of the HIV LTR. Thus, induction of epigenetic silencing by histone and DNA methylation appears to be insufficient to permanently silence HIV-1 proviral transcription.
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Affiliation(s)
- Kien Nguyen
- Department of Molecular Biology and Microbiology, Case Western Reserve University Medical School, Cleveland, Ohio, United States of America
| | - Curtis Dobrowolski
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory School of Medicine, Atlanta, Georgia, United States of America
| | - Meenakshi Shukla
- Department of Molecular Biology and Microbiology, Case Western Reserve University Medical School, Cleveland, Ohio, United States of America
| | - Won-Kyung Cho
- Korean Medicine (KM)-Application Center, Korea Institute of Oriental Medicine (KIOM), Dong-gu, Daegu, Republic of Korea
| | - Benjamin Luttge
- Department of Molecular Biology and Microbiology, Case Western Reserve University Medical School, Cleveland, Ohio, United States of America
| | - Jonathan Karn
- Department of Molecular Biology and Microbiology, Case Western Reserve University Medical School, Cleveland, Ohio, United States of America
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28
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Mbonye U, Leskov K, Shukla M, Valadkhan S, Karn J. Biogenesis of P-TEFb in CD4+ T cells to reverse HIV latency is mediated by protein kinase C (PKC)-independent signaling pathways. PLoS Pathog 2021; 17:e1009581. [PMID: 34529720 PMCID: PMC8478230 DOI: 10.1371/journal.ppat.1009581] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2021] [Revised: 09/28/2021] [Accepted: 09/04/2021] [Indexed: 01/09/2023] Open
Abstract
The switch between HIV latency and productive transcription is regulated by an auto-feedback mechanism initiated by the viral trans-activator Tat, which functions to recruit the host transcription elongation factor P-TEFb to proviral HIV. A heterodimeric complex of CDK9 and one of three cyclin T subunits, P-TEFb is expressed at vanishingly low levels in resting memory CD4+ T cells and cellular mechanisms controlling its availability are central to regulation of the emergence of HIV from latency. Using a well-characterized primary T-cell model of HIV latency alongside healthy donor memory CD4+ T cells, we characterized specific T-cell receptor (TCR) signaling pathways that regulate the generation of transcriptionally active P-TEFb, defined as the coordinate expression of cyclin T1 and phospho-Ser175 CDK9. Protein kinase C (PKC) agonists, such as ingenol and prostratin, stimulated active P-TEFb expression and reactivated latent HIV with minimal cytotoxicity, even in the absence of intracellular calcium mobilization with an ionophore. Unexpectedly, inhibition-based experiments demonstrated that PKC agonists and TCR-mobilized diacylglycerol signal through MAP kinases ERK1/2 rather than through PKC to effect the reactivation of both P-TEFb and latent HIV. Single-cell and bulk RNA-seq analyses revealed that of the four known isoforms of the Ras guanine nucleotide exchange factor RasGRP, RasGRP1 is by far the predominantly expressed diacylglycerol-dependent isoform in CD4+ T cells. RasGRP1 should therefore mediate the activation of ERK1/2 via Ras-Raf signaling upon TCR co-stimulation or PKC agonist challenge. Combined inhibition of the PI3K-mTORC2-AKT-mTORC1 pathway and the ERK1/2 activator MEK prior to TCR co-stimulation abrogated active P-TEFb expression and substantially suppressed latent HIV reactivation. Therefore, contrary to prevailing models, the coordinate reactivation of P-TEFb and latent HIV in primary T cells following either TCR co-stimulation or PKC agonist challenge is independent of PKC but rather involves two complementary signaling arms of the TCR cascade, namely, RasGRP1-Ras-Raf-MEK-ERK1/2 and PI3K-mTORC2-AKT-mTORC1.
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Affiliation(s)
- Uri Mbonye
- Department of Molecular Biology and Microbiology, Case Western Reserve University School of Medicine, Cleveland, Ohio, United States of America
- * E-mail: (UM); (JK)
| | - Konstantin Leskov
- Department of Molecular Biology and Microbiology, Case Western Reserve University School of Medicine, Cleveland, Ohio, United States of America
| | - Meenakshi Shukla
- Department of Molecular Biology and Microbiology, Case Western Reserve University School of Medicine, Cleveland, Ohio, United States of America
| | - Saba Valadkhan
- Department of Molecular Biology and Microbiology, Case Western Reserve University School of Medicine, Cleveland, Ohio, United States of America
| | - Jonathan Karn
- Department of Molecular Biology and Microbiology, Case Western Reserve University School of Medicine, Cleveland, Ohio, United States of America
- * E-mail: (UM); (JK)
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29
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Tomassi S, Romanelli A, Zwergel C, Valente S, Mai A. Polycomb Repressive Complex 2 Modulation through the Development of EZH2-EED Interaction Inhibitors and EED Binders. J Med Chem 2021; 64:11774-11797. [PMID: 34351144 PMCID: PMC8404197 DOI: 10.1021/acs.jmedchem.1c00226] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
![]()
Epigenetics is nowadays
a well-accepted area of research. In the
last years, tremendous progress was made regarding molecules targeting
EZH2, directly or indirectly. Recently tazemetostat hit the market
after FDA-approval for the treatment of lymphoma. However, the impairment
of EZH2 activity by orthosteric intervention has proven to be effective
only in a limited subset of cancers. Considering the multiproteic
nature of the PRC2 complex and the marked dependence of EZH2 functions
on the other core subunits such as EED, in recent years, a new targeting
approach ascended to prominence. The possibility to cripple the function
of the PRC2 complex by interfering with its multimeric integrity fueled
the interest in developing EZH2–EED protein–protein
interaction and EED inhibitors as indirect modulators of PRC2-dependent
methyltransferase activity. In this Perspective, we aim to summarize
the latest findings regarding the development and the biological activity
of these emerging classes of PRC2 modulators from a medicinal chemist’s
viewpoint.
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Affiliation(s)
- Stefano Tomassi
- Department of Pharmacy, University of Naples "Federico II", Via D. Montesano 49, 80131 Naples, Italy
| | - Annalisa Romanelli
- Department of Chemistry and Technology of Drugs, "Sapienza" University of Rome, P.le A. Moro 5, 00185 Rome, Italy
| | - Clemens Zwergel
- Department of Chemistry and Technology of Drugs, "Sapienza" University of Rome, P.le A. Moro 5, 00185 Rome, Italy
| | - Sergio Valente
- Department of Chemistry and Technology of Drugs, "Sapienza" University of Rome, P.le A. Moro 5, 00185 Rome, Italy
| | - Antonello Mai
- Department of Chemistry and Technology of Drugs, "Sapienza" University of Rome, P.le A. Moro 5, 00185 Rome, Italy
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FKBP3 Induces Human Immunodeficiency Virus Type 1 Latency by Recruiting Histone Deacetylase 1/2 to the Viral Long Terminal Repeat. mBio 2021; 12:e0079521. [PMID: 34281390 PMCID: PMC8406261 DOI: 10.1128/mbio.00795-21] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Human immunodeficiency virus type 1 (HIV-1) cannot be completely eliminated because of existence of the latent HIV-1 reservoir. However, the facts of HIV-1 latency, including its establishment and maintenance, are incomplete. FKBP3, encoded by the FKBP3 gene, belongs to the immunophilin family of proteins and is involved in immunoregulation and such cellular processes as protein folding. In a previous study, we found that FKBP3 may be related to HIV-1 latency using CRISPR screening. In this study, we knocked out the FKBP3 gene in multiple latently infected cell lines to promote latent HIV-1 activation. We found that FKBP3 could indirectly bind to the HIV-1 long terminal repeat through interaction with YY1, thereby recruiting histone deacetylase 1/2 to it. This promotes histone deacetylation and induces HIV-1 latency. Finally, in a primary latent cell model, we confirmed the effect of FKBP3 knockout on the latent activation of HIV-1. Our results suggest a new mechanism for the epigenetic regulation of HIV-1 latency and a new potential target for activating latent HIV-1.
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31
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Ding J, Liu Y, Lai Y. Knowledge From London and Berlin: Finding Threads to a Functional HIV Cure. Front Immunol 2021; 12:688747. [PMID: 34122453 PMCID: PMC8190402 DOI: 10.3389/fimmu.2021.688747] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2021] [Accepted: 05/04/2021] [Indexed: 01/07/2023] Open
Abstract
Despite the ability of combination antiretroviral therapy (cART) to increase the life expectancy of patients infected with human immunodeficiency virus (HIV), viral reservoirs persist during life-long treatment. Notably, two cases of functional cure for HIV have been reported and are known as the "Berlin Patient" and the "London Patient". Both patients received allogeneic hematopoietic stem cell transplantation from donors with homozygous CCR5 delta32 mutation for an associated hematological malignancy. Therefore, there is growing interest in creating an HIV-resistant immune system through the use of gene-modified autologous hematopoietic stem cells with non-functional CCR5. Moreover, studies in CXCR4-targeted gene therapy for HIV have also shown great promise. Developing a cure for HIV infection remains a high priority. In this review, we discuss the increasing progress of coreceptor-based hematopoietic stem cell gene therapy, cART, milder conditioning regimens, and shock and kill strategies that have important implications for designing potential strategies aiming to achieve a functional cure for the majority of people with HIV.
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Affiliation(s)
- Jingyi Ding
- Hospital of Chengdu University of Traditional Chinese Medicine, Chengdu, China
| | - Yanxi Liu
- University of California, Los Angeles, Los Angeles, CA, United States
| | - Yu Lai
- School of Basic Medicine, Chengdu University of Traditional Chinese Medicine, Chengdu, China,*Correspondence: Yu Lai,
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32
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Epigenetic Mechanisms of HIV-1 Persistence. Vaccines (Basel) 2021; 9:vaccines9050514. [PMID: 34067608 PMCID: PMC8156729 DOI: 10.3390/vaccines9050514] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2021] [Revised: 05/01/2021] [Accepted: 05/11/2021] [Indexed: 12/14/2022] Open
Abstract
Eradicating HIV-1 in infected individuals will not be possible without addressing the persistence of the virus in its multiple reservoirs. In this context, the molecular characterization of HIV-1 persistence is key for the development of rationalized therapeutic interventions. HIV-1 gene expression relies on the redundant and cooperative recruitment of cellular epigenetic machineries to cis-regulatory proviral regions. Furthermore, the complex repertoire of HIV-1 repression mechanisms varies depending on the nature of the viral reservoir, although, so far, few studies have addressed the specific regulatory mechanisms of HIV-1 persistence in other reservoirs than the well-studied latently infected CD4+ T cells. Here, we present an exhaustive and updated picture of the heterochromatinization of the HIV-1 promoter in its different reservoirs. We highlight the complexity, heterogeneity and dynamics of the epigenetic mechanisms of HIV-1 persistence, while discussing the importance of further understanding HIV-1 gene regulation for the rational design of novel HIV-1 cure strategies.
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33
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Svensson JP. Targeting Epigenetics to Cure HIV-1: Lessons From (and for) Cancer Treatment. Front Cell Infect Microbiol 2021; 11:668637. [PMID: 34026665 PMCID: PMC8137950 DOI: 10.3389/fcimb.2021.668637] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2021] [Accepted: 04/21/2021] [Indexed: 11/17/2022] Open
Abstract
The Human Immunodeficiency Virus type 1 (HIV-1) integrates in the host genome as a provirus resulting in a long-lived reservoir of infected CD4 cells. As a provirus, HIV-1 has several aspects in common with an oncogene. Both the HIV-1 provirus and oncogenes only cause disease when expressed. A successful cure of both cancer and HIV-1 includes elimination of all cells with potential to regenerate the disease. For over two decades, epigenetic drugs developed against cancer have been used in the HIV-1 field to modulate the state of the proviral chromatin. Cells with an intact HIV-1 provirus exist in three states of infection: productive, inducible latent, and non-inducible latent. Here focus is on HIV-1, transcription control and chromatin structure; how the inducible proviruses are maintained in a chromatin structure that allows reactivation of transcription; and how transcription switches between different stages to allow for an abundance of different transcripts from a single promoter. Recently it was shown that a functional cure of HIV can be achieved by encapsulating all intact HIV-1 proviruses in heterochromatin, giving hope that epigenetic interventions may be used to end the HIV-1 epidemic.
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Affiliation(s)
- J Peter Svensson
- Department of Biosciences and Nutrition, Karolinska Institutet (KI), Huddinge, Sweden
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34
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Beshore DC, Adam GC, Barnard RJO, Burlein C, Gallicchio SN, Holloway MK, Krosky D, Lemaire W, Myers RW, Patel S, Plotkin MA, Powell DA, Rada V, Cox CD, Coleman PJ, Klein DJ, Wolkenberg SE. Redefining the Histone Deacetylase Inhibitor Pharmacophore: High Potency with No Zinc Cofactor Interaction. ACS Med Chem Lett 2021; 12:540-547. [PMID: 33854701 PMCID: PMC8040053 DOI: 10.1021/acsmedchemlett.1c00074] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2021] [Accepted: 02/24/2021] [Indexed: 01/04/2023] Open
Abstract
A novel series of histone deacetylase (HDAC) inhibitors lacking a zinc-binding moiety has been developed and described herein. HDAC isozyme profiling and kinetic studies indicate that these inhibitors display a selectivity preference for HDACs 1, 2, 3, 10, and 11 via a rapid equilibrium mechanism, and crystal structures with HDAC2 confirm that these inhibitors do not interact with the catalytic zinc. The compounds are nonmutagenic and devoid of electrophilic and mutagenic structural elements and exhibit off-target profiles that are promising for further optimization. The efficacy of this new class in biochemical and cell-based assays is comparable to the marketed HDAC inhibitors belinostat and vorinostat. These results demonstrate that the long-standing pharmacophore model of HDAC inhibitors requiring a metal binding motif should be revised and offers a distinct class of HDAC inhibitors.
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Affiliation(s)
| | - Gregory C. Adam
- MRL, Merck & Co., Inc., Kenilworth, New Jersey 07033, United States
| | | | | | | | | | - Daniel Krosky
- MRL, Merck & Co., Inc., Kenilworth, New Jersey 07033, United States
| | - Wei Lemaire
- MRL, Merck & Co., Inc., Kenilworth, New Jersey 07033, United States
| | - Robert W. Myers
- MRL, Merck & Co., Inc., Kenilworth, New Jersey 07033, United States
| | - Sangita Patel
- MRL, Merck & Co., Inc., Kenilworth, New Jersey 07033, United States
| | | | - David A. Powell
- MRL, Merck & Co., Inc., Kenilworth, New Jersey 07033, United States
| | - Vanessa Rada
- MRL, Merck & Co., Inc., Kenilworth, New Jersey 07033, United States
| | | | - Paul J. Coleman
- MRL, Merck & Co., Inc., Kenilworth, New Jersey 07033, United States
| | - Daniel J. Klein
- MRL, Merck & Co., Inc., Kenilworth, New Jersey 07033, United States
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35
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McMillan A, Nguyen MK, Huynh CT, Sarett SM, Ge P, Chetverikova M, Nguyen K, Grosh D, Duvall CL, Alsberg E. Hydrogel microspheres for spatiotemporally controlled delivery of RNA and silencing gene expression within scaffold-free tissue engineered constructs. Acta Biomater 2021; 124:315-326. [PMID: 33465507 DOI: 10.1016/j.actbio.2021.01.013] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2020] [Revised: 01/08/2021] [Accepted: 01/12/2021] [Indexed: 12/18/2022]
Abstract
Delivery systems for controlled release of RNA interference (RNAi) molecules, including small interfering (siRNA) and microRNA (miRNA), have the potential to direct stem cell differentiation for regenerative musculoskeletal applications. To date, localized RNA delivery platforms in this area have focused predominantly on bulk scaffold-based approaches, which can interfere with cell-cell interactions important for recapitulating some native musculoskeletal developmental and healing processes in tissue regeneration strategies. In contrast, scaffold-free, high density human mesenchymal stem cell (hMSC) aggregates may provide an avenue for creating a more biomimetic microenvironment. Here, photocrosslinkable dextran microspheres (MS) encapsulating siRNA-micelles were prepared via an aqueous emulsion method and incorporated within hMSC aggregates for localized and sustained delivery of bioactive siRNA. siRNA-micelles released from MS in a sustained fashion over the course of 28 days, and the released siRNA retained its ability to transfect cells for gene silencing. Incorporation of fluorescently labeled siRNA (siGLO)-laden MS within hMSC aggregates exhibited tunable siGLO delivery and uptake by stem cells. Incorporation of MS loaded with siRNA targeting green fluorescent protein (siGFP) within GFP-hMSC aggregates provided sustained presentation of siGFP within the constructs and prolonged GFP silencing for up to 15 days. This platform system enables sustained gene silencing within stem cell aggregates and thus shows great potential in tissue regeneration applications. STATEMENT OF SIGNIFICANCE: This work presents a new strategy to deliver RNA-nanocomplexes from photocrosslinked dextran microspheres for tunable presentation of bioactive RNA. These microspheres were embedded within scaffold-free, human mesenchymal stem cell (hMSC) aggregates for sustained gene silencing within three-dimensional cell constructs while maintaining cell viability. Unlike exogenous delivery of RNA within culture medium that suffers from diffusion limitations and potential need for repeated transfections, this strategy provides local and sustained RNA presentation from the microspheres to cells in the constructs. This system has the potential to inhibit translation of hMSC differentiation antagonists and drive hMSC differentiation toward desired specific lineages, and is an important step in the engineering of high-density stem cell systems with incorporated instructive genetic cues for application in tissue regeneration.
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36
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Janssens J, Bruggemans A, Christ F, Debyser Z. Towards a Functional Cure of HIV-1: Insight Into the Chromatin Landscape of the Provirus. Front Microbiol 2021; 12:636642. [PMID: 33868195 PMCID: PMC8044952 DOI: 10.3389/fmicb.2021.636642] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2020] [Accepted: 02/09/2021] [Indexed: 12/19/2022] Open
Abstract
Despite potent combination antiretroviral therapy, HIV-1 infection persists due to irreversible integration of the virus in long-living cells of the immune system. The main focus of HIV-1 cure strategies has been on HIV-1 eradication, yet without great success so far. Therefore, HIV-1 remission or a functional cure, whereby the virus is silenced rather than eradicated, is considered as an alternative strategy. Elite controllers, individuals who spontaneously control HIV-1, may point us the way toward a functional HIV-1 cure. In order to achieve such a cure, a profound understanding of the mechanisms controlling HIV-1 expression and silencing is needed. In recent years, evidence has grown that the site of integration as well as the chromatin landscape surrounding the integration site affects the transcriptional state of the provirus. Still, at present, the impact of integration site selection on the establishment and maintenance of the HIV-1 reservoirs remains poorly understood. The discovery of LEDGF/p75 as a binding partner of HIV-1 integrase has led to a better understanding of integration site selection. LEDGF/p75 is one of the important determinants of integration site selection and targets integration toward active genes. In this review, we will provide an overview of the most important determinants of integration site selection. Secondly, we will discuss the chromatin landscape at the integration site and its implications on HIV-1 gene expression and silencing. Finally, we will discuss how interventions that affect integration site selection or modifications of the chromatin could yield a functional cure of HIV-1 infection.
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Affiliation(s)
- Julie Janssens
- Laboratory for Molecular Virology and Gene Therapy, Department of Pharmaceutical and Pharmacological Sciences, KU Leuven, Leuven, Belgium
| | - Anne Bruggemans
- Laboratory for Molecular Virology and Gene Therapy, Department of Pharmaceutical and Pharmacological Sciences, KU Leuven, Leuven, Belgium
| | - Frauke Christ
- Laboratory for Molecular Virology and Gene Therapy, Department of Pharmaceutical and Pharmacological Sciences, KU Leuven, Leuven, Belgium
| | - Zeger Debyser
- Laboratory for Molecular Virology and Gene Therapy, Department of Pharmaceutical and Pharmacological Sciences, KU Leuven, Leuven, Belgium
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37
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Chandar Charles MR, Li MC, Hsieh HP, Coumar MS. Mimicking H3 Substrate Arginine in the Design of G9a Lysine Methyltransferase Inhibitors for Cancer Therapy: A Computational Study for Structure-Based Drug Design. ACS OMEGA 2021; 6:6100-6111. [PMID: 33718701 PMCID: PMC7948220 DOI: 10.1021/acsomega.0c04710] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/24/2020] [Accepted: 02/09/2021] [Indexed: 05/30/2023]
Abstract
G9a protein methyltransferase is a potential epigenetic drug target in different cancers and other disease conditions overexpressing the enzyme. G9a is responsible for the H3K9 dimethylation mark, which epigenetically regulates gene expression. Arg8 and Lys9 of the H3 substrate peptide are the two crucial residues for substrate-specific recognition and methylation. Several substrate competitive inhibitors are reported for the potent inhibition of G9a by incorporating lysine mimic groups in the inhibitor design. In this study, we explored the concept of arginine mimic strategy. The hydrophobic segment of the reported inhibitors BIX-01294 and UNC0638 was replaced by a guanidine moiety (side-chain moiety of arginine). The newly substituted guanidine moieties of the inhibitors were positioned similar to the Arg8 of the substrate peptide in molecular docking. Additionally, improved reactivity of the guanidine-substituted inhibitors was observed in density functional theory studies. Molecular dynamics, molecular mechanics Poisson-Boltzmann surface area binding free energy, linear interaction energy, and potential mean force calculated from steered molecular dynamics simulations of the newly designed analogues show enhanced conformational stability and improved H-bond potential and binding affinity toward the target G9a. Moreover, the presence of both lysine and arginine mimics together shows a drastic increase in the binding affinity of the inhibitor towards G9a. Hence, we propose incorporating a guanidine group to imitate the substrate arginine's side chain in the inhibitor design to improve the potency of G9a inhibitors.
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Affiliation(s)
- M. Ramya Chandar Charles
- Centre
for Bioinformatics, School of Life Sciences, Pondicherry University, Kalapet, Puducherry 605014, India
| | - Mu-Chun Li
- Institute
of Biotechnology and Pharmaceutical Research, National Health Research Institutes, 35 Keyan Road, Zhunan, Miaoli
County, Taiwan 350, ROC
- Department
of Chemistry, National Tsing Hua University, No. 101, Section 2, Kuang-Fu Road, Hsinchu 300, Taiwan
| | - Hsing-Pang Hsieh
- Institute
of Biotechnology and Pharmaceutical Research, National Health Research Institutes, 35 Keyan Road, Zhunan, Miaoli
County, Taiwan 350, ROC
- Department
of Chemistry, National Tsing Hua University, No. 101, Section 2, Kuang-Fu Road, Hsinchu 300, Taiwan
- Biomedical
Translation Research Center, Academia Sinica, Taipei 115, Taiwan
| | - Mohane Selvaraj Coumar
- Centre
for Bioinformatics, School of Life Sciences, Pondicherry University, Kalapet, Puducherry 605014, India
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Zhang XN, Wu LJ, Kong X, Zheng BY, Zhang Z, He ZW. Regulation of the expression of proinflammatory cytokines induced by SARS-CoV-2. World J Clin Cases 2021; 9:1513-1523. [PMID: 33728295 PMCID: PMC7942047 DOI: 10.12998/wjcc.v9.i7.1513] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/13/2020] [Revised: 12/08/2020] [Accepted: 12/25/2020] [Indexed: 02/06/2023] Open
Abstract
An outbreak of a novel coronavirus was reported in Wuhan, China, in late 2019. It has spread rapidly through China and many other countries, causing a global pandemic. Since February 2020, over 28 countries/regions have reported confirmed cases. Individuals with the infection known as coronavirus disease-19 (COVID-19) have similar clinical features as severe acute respiratory syndrome first encountered 17 years ago, with fever, cough, and upper airway congestion, along with high production of proinflammatory cytokines (PICs), which form a cytokine storm. PICs induced by COVID-19 include interleukin (IL)-6, IL-17, and monocyte chemoattractant protein-1. The production of cytokines is regulated by activated nuclear factor-kB and involves downstream pathways such as Janus kinase/signal transducers and activators transcription. Protein expression is also regulated by post-translational modification of chromosomal markers. Lysine residues in the peptide tails stretching out from the core of histones bind the sequence upstream of the coding portion of genomic DNA. Covalent modification, particularly methylation, activates or represses gene transcription. PICs have been reported to be induced by histone modification and stimulate exudation of hyaluronic acid, which is implicated in the occurrence of COVID-19. These findings indicate the impact of the expression of PICs on the pathogenesis and therapeutic targeting of COVID-19.
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Affiliation(s)
- Xiang-Ning Zhang
- Department of Pathophysiology, Guangdong Medical University, Dongguan 523808, Guangdong Province, China
| | - Long-Ji Wu
- Department of Pathophysiology, Guangdong Medical University, Dongguan 523808, Guangdong Province, China
| | - Xia Kong
- Department of Pathophysiology, Guangdong Medical University, Dongguan 523808, Guangdong Province, China
| | - Bi-Ying Zheng
- Department of Clinical Microbiology, Institute of Laboratory Medicine, Guangdong Medical University, Dongguan 523808, Guangdong Province, China
| | - Zhe Zhang
- Department of ENT and Head and Neck Surgery, First Affiliated Hospital of Guangxi Medical University, Nanning 531000, Guangxi Zhuang Autonomous Region, China
| | - Zhi-Wei He
- Department of Pathophysiology, Guangdong Medical University, Dongguan 523808, Guangdong Province, China
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39
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HIV latency reversal agents: A potential path for functional cure? Eur J Med Chem 2021; 213:113213. [PMID: 33540228 DOI: 10.1016/j.ejmech.2021.113213] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2020] [Revised: 11/16/2020] [Accepted: 01/12/2021] [Indexed: 12/28/2022]
Abstract
Despite the advances in Human Immunodeficiency Virus (HIV) treatment, the cure for all HIV patients still poses a major challenge, which needs to be surpassed in the coming years. Among the strategies pursuing this aim, the 'kick-and-kill' approach, which involves the reactivation and elimination of a latent HIV reservoir that resides in some CD4+ T cells, appears promising. The first step of this approach requires the use of latency reversal agents (LRAs) that induce the reactivation of the latent virus. Although several classes of LRAs have been reported so far, some limitations of these compounds still need to be overcome before their clinical use. The complete exhaustion of the reservoir of latent virus will contribute to promote the second step of this approach, facilitating the elimination of the reactivated HIV. Therefore, potent, safe, and non-toxic LRAs are necessary to promote efficient elimination of the HIV-1 virus from its reservoir. In this review article, we focus on the promising LRAs that have been described in the literature over the past few years, highlighting the advantages and disadvantages of their use in the 'kick and kill' approach, thus opening a new avenue in the development of a potential cure.
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40
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Krasnopolsky S, Novikov A, Kuzmina A, Taube R. CRISPRi-mediated depletion of Spt4 and Spt5 reveals a role for DSIF in the control of HIV latency. BIOCHIMICA ET BIOPHYSICA ACTA-GENE REGULATORY MECHANISMS 2020; 1864:194656. [PMID: 33333262 DOI: 10.1016/j.bbagrm.2020.194656] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Received: 06/29/2020] [Revised: 11/15/2020] [Accepted: 11/16/2020] [Indexed: 01/03/2023]
Abstract
Pivotal studies on the control of HIV transcription has laid the foundations for our understanding of how metazoan transcription is executed, and what are the factors that control this step. Part of this work established a role for DRB Sensitivity Inducing Factor (DSIF), consisting of Spt4 and Spt5, in promoting pause-release of RNA Polymerase II (Pol II) for optimal elongation. However, while there has been substantial progress in understanding the role of DSIF in mediating HIV gene transcription, its involvement in establishing viral latency has not been explored. Moreover, the effects of depleting Spt4 or Spt5, or simultaneously knocking down both subunits of DSIF have not been examined. In this study, we employed CRISPR interference (CRIPSRi) to knockdown the expression of Spt4, Spt5 or the entire DSIF complex, and monitored effects on HIV transcription and viral latency. Knocking down DSIF, or each of its subunits, inhibited HIV transcription, primarily at the step of Tat transactivation. This was accompanied by a decrease in promoter occupancy of Pol II and Cdk9, and to a lesser extent, AFF4. Interestingly, targeting the expression of one subunit of DSIF, reduced the protein stability of its counterpart partner. Moreover, depletion of Spt4, Spt5 or DSIF complex impaired cell growth, but did not cause cell death. Finally, knockdown of Spt4, Spt5 or DSIF, facilitated entry of HIV into latency. We conclude that each DSIF subunit plays a role in maintaining the stability of its other partner, achieving optimal function of the DSIF to enhance viral gene transcription.
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Affiliation(s)
- Simona Krasnopolsky
- The Shraga Segal Department of Microbiology Immunology and Genetics Faculty of Health Sciences, Ben-Gurion University of the Negev, Israel
| | - Alex Novikov
- The Shraga Segal Department of Microbiology Immunology and Genetics Faculty of Health Sciences, Ben-Gurion University of the Negev, Israel
| | - Alona Kuzmina
- The Shraga Segal Department of Microbiology Immunology and Genetics Faculty of Health Sciences, Ben-Gurion University of the Negev, Israel
| | - Ran Taube
- The Shraga Segal Department of Microbiology Immunology and Genetics Faculty of Health Sciences, Ben-Gurion University of the Negev, Israel.
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Fujinaga K, Cary DC. Experimental Systems for Measuring HIV Latency and Reactivation. Viruses 2020; 12:v12111279. [PMID: 33182414 PMCID: PMC7696534 DOI: 10.3390/v12111279] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2020] [Revised: 11/02/2020] [Accepted: 11/05/2020] [Indexed: 02/07/2023] Open
Abstract
The final obstacle to achieving a cure to HIV/AIDS is the presence of latent HIV reservoirs scattered throughout the body. Although antiretroviral therapy maintains plasma viral loads below the levels of detection, upon cessation of therapy, the latent reservoir immediately produces infectious progeny viruses. This results in elevated plasma viremia, which leads to clinical progression to AIDS. Thus, if a HIV cure is ever to become a reality, it will be necessary to target and eliminate the latent reservoir. To this end, tremendous effort has been dedicated to locate the viral reservoir, understand the mechanisms contributing to latency, find optimal methods to reactivate HIV, and specifically kill latently infected cells. Although we have not yet identified a therapeutic approach to completely eliminate HIV from patients, these efforts have provided many technological breakthroughs in understanding the underlying mechanisms that regulate HIV latency and reactivation in vitro. In this review, we summarize and compare experimental systems which are frequently used to study HIV latency. While none of these models are a perfect proxy for the complex systems at work in HIV+ patients, each aim to replicate HIV latency in vitro.
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Affiliation(s)
- Koh Fujinaga
- Division of Rheumatology, Department of Medicine, School of Medicine, University of California, San Francisco, CA 94143-0703, USA
- Correspondence: ; Tel.: +1-415-502-1908
| | - Daniele C. Cary
- Department of Medicine, Microbiology, and Immunology, School of Medicine, University of California, San Francisco, CA 94143-0703, USA;
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Regulation of Expression and Latency in BLV and HTLV. Viruses 2020; 12:v12101079. [PMID: 32992917 PMCID: PMC7601775 DOI: 10.3390/v12101079] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2020] [Revised: 09/20/2020] [Accepted: 09/21/2020] [Indexed: 12/14/2022] Open
Abstract
Human T-lymphotrophic virus type 1 (HTLV-1) and Bovine leukemia virus (BLV) belong to the Deltaretrovirus genus. HTLV-1 is the etiologic agent of the highly aggressive and currently incurable cancer adult T-cell leukemia (ATL) and a neurological disease HTLV-1-associated myelopathy (HAM)/tropical spastic paraparesis (TSP). BLV causes neoplastic proliferation of B cells in cattle: enzootic bovine leucosis (EBL). Despite the severity of these conditions, infection by HTLV-1 and BLV appear in most cases clinically asymptomatic. These viruses can undergo latency in their hosts. The silencing of proviral gene expression and maintenance of latency are central for the establishment of persistent infection, as well as for pathogenesis in vivo. In this review, we will present the mechanisms that control proviral activation and retroviral latency in deltaretroviruses, in comparison with other exogenous retroviruses. The 5′ long terminal repeats (5′-LTRs) play a main role in controlling viral gene expression. While the regulation of transcription initiation is a major mechanism of silencing, we discuss topics that include (i) the epigenetic control of the provirus, (ii) the cis-elements present in the LTR, (iii) enhancers with cell-type specific regulatory functions, (iv) the role of virally-encoded transactivator proteins, (v) the role of repressors in transcription and silencing, (vi) the effect of hormonal signaling, (vii) implications of LTR variability on transcription and latency, and (viii) the regulatory role of non-coding RNAs. Finally, we discuss how a better understanding of these mechanisms may allow for the development of more effective treatments against Deltaretroviruses.
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Vansant G, Chen HC, Zorita E, Trejbalová K, Miklík D, Filion G, Debyser Z. The chromatin landscape at the HIV-1 provirus integration site determines viral expression. Nucleic Acids Res 2020; 48:7801-7817. [PMID: 32597987 PMCID: PMC7641320 DOI: 10.1093/nar/gkaa536] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2020] [Revised: 06/07/2020] [Accepted: 06/12/2020] [Indexed: 02/06/2023] Open
Abstract
HIV-1 persists lifelong in memory cells of the immune system as latent provirus that rebounds upon treatment interruption. Therefore, the latent reservoir is the main target for an HIV cure. Here, we studied the direct link between integration site and transcription using LEDGINs and Barcoded HIV-ensembles (B-HIVE). LEDGINs are antivirals that inhibit the interaction between HIV-1 integrase and the chromatin-tethering factor LEDGF/p75. They were used as a tool to retarget integration, while the effect on HIV expression was measured with B-HIVE. B-HIVE tracks insert-specific HIV expression by tagging a unique barcode in the HIV genome. We confirmed that LEDGINs retarget integration out of gene-dense and actively transcribed regions. The distance to H3K36me3, the marker recognized by LEDGF/p75, clearly increased. LEDGIN treatment reduced viral RNA expression and increased the proportion of silent provirus. Finally, silent proviruses obtained after LEDGIN treatment were located further away from epigenetic marks associated with active transcription. Interestingly, proximity to enhancers stimulated transcription irrespective of LEDGIN treatment, while the distance to H3K36me3 only changed after treatment with LEDGINs. The fact that proximity to these markers are associated with RNA expression support the direct link between provirus integration site and viral expression.
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Affiliation(s)
- Gerlinde Vansant
- Laboratory for Molecular Virology and Gene Therapy, Department of Pharmaceutical and Pharmacological Sciences, KU Leuven, Leuven, Flanders, Belgium
| | - Heng-Chang Chen
- Center for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, Barcelona, Catalunya, Spain
| | - Eduard Zorita
- Center for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, Barcelona, Catalunya, Spain
| | - Katerina Trejbalová
- Institute of Molecular Genetics, Czech Academy of Sciences, Videnska, Prague, Czech Republic
| | - Dalibor Miklík
- Institute of Molecular Genetics, Czech Academy of Sciences, Videnska, Prague, Czech Republic
| | - Guillaume Filion
- Center for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, Barcelona, Catalunya, Spain.,University Pompeu Fabra, Barcelona, Catalunya, Spain
| | - Zeger Debyser
- Laboratory for Molecular Virology and Gene Therapy, Department of Pharmaceutical and Pharmacological Sciences, KU Leuven, Leuven, Flanders, Belgium
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Genome-wide CRISPR knockout screen identifies ZNF304 as a silencer of HIV transcription that promotes viral latency. PLoS Pathog 2020; 16:e1008834. [PMID: 32956422 PMCID: PMC7529202 DOI: 10.1371/journal.ppat.1008834] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2020] [Revised: 10/01/2020] [Accepted: 07/22/2020] [Indexed: 12/17/2022] Open
Abstract
Despite the widespread use of anti-retroviral therapy, human immunodeficiency virus (HIV) still persists in an infected cell reservoir that harbors transcriptionally silent yet replication-competent proviruses. While significant progress has been made in understanding how the HIV reservoir is established, transcription repression mechanisms that are enforced on the integrated viral promoter have not been fully revealed. In this study, we performed a whole-genome CRISPR knockout screen in HIV infected T cells to identify host genes that potentially promote HIV latency. Of several top candidates, the KRAB-containing zinc finger protein, ZNF304, was identified as the top hit. ZNF304 silences HIV gene transcription through associating with TRIM28 and recruiting to the viral promoter heterochromatin-inducing methyltransferases, including the polycomb repression complex (PRC) and SETB1. Depletion of ZNF304 expression reduced levels of H3K9me3, H3K27me3 and H2AK119ub repressive histone marks on the HIV promoter as well as SETB1 and TRIM28, ultimately enhancing HIV gene transcription. Significantly, ZNF304 also promoted HIV latency, as its depletion delayed the entry of HIV infected cells into latency. In primary CD4+ cells, ectopic expression of ZNF304 silenced viral transcription. We conclude that by associating with TRIM28 and recruiting host transcriptional repressive complexes, SETB1 and PRC, to the HIV promoter, ZNF304 silences HIV gene transcription and promotes viral latency. Antiretroviral therapy has significantly decreased the morbidity and mortality associated with HIV infection. However, a complete cure remains out of reach, as HIV persists in a cell reservoir that is highly stable in the face of therapy. While developing novel therapeutic strategies to eliminate the reservoir is a well-recognized goal, knowledge of the molecular events that establish HIV latency is still not complete. To obtain insights into the silencing mechanisms of HIV gene transcription and the establishment of viral latency, a genome-wide CRISPR screen was employed to identify host factors that control viral latency. We identified zinc-finger protein 304 (ZNF304) and showed that through association with TRIM28, it recruits the histone methyltransferases SETB1 and PRC to deposit repressive marks on chromatin of the HIV promoter, thereby facilitating the silencing of viral gene transcription. Moreover, we found that depletion of ZNF304 expression activated HIV gene expression, while ZNF304 overexpression repressed viral gene transcription both in a T cell line and in primary CD4+ cells. Finally, our study showed that ZNF304 is also involved in modulating HIV latency, as its depletion delayed entry of the virus into a latency state. Our results offer an additional mechanistic explanation for how host histone repression complexes are tethered to the HIV promoter to promote chromatin compaction, thereby defining a potentially new target for perturbing the establishment of the viral reservoir.
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CBF-1 Promotes the Establishment and Maintenance of HIV Latency by Recruiting Polycomb Repressive Complexes, PRC1 and PRC2, at HIV LTR. Viruses 2020; 12:v12091040. [PMID: 32961937 PMCID: PMC7551090 DOI: 10.3390/v12091040] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2020] [Revised: 09/09/2020] [Accepted: 09/16/2020] [Indexed: 12/18/2022] Open
Abstract
The C-promoter binding factor-1 (CBF-1) is a potent and specific inhibitor of the human immunodeficiency virus (HIV)-1 LTR promoter. Here, we demonstrate that the knockdown of endogenous CBF-1 in latently infected primary CD4+ T cells, using specific small hairpin RNAs (shRNA), resulted in the reactivation of latent HIV proviruses. Chromatin immunoprecipitation (ChIP) assays using latently infected primary T cells and Jurkat T-cell lines demonstrated that CBF-1 induces the establishment and maintenance of HIV latency by recruiting polycomb group (PcG/PRC) corepressor complexes or polycomb repressive complexes 1 and 2 (PRC1 and PRC2). Knockdown of CBF-1 resulted in the dissociation of PRCs corepressor complexes enhancing the recruitment of RNA polymerase II (RNAP II) at HIV LTR. Knockdown of certain components of PRC1 and PRC2 also led to the reactivation of latent proviruses. Similarly, the treatment of latently infected primary CD4+ T cells with the PRC2/EZH2 inhibitor, 3-deazaneplanocin A (DZNep), led to their reactivation.
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Turner AMW, Dronamraju R, Potjewyd F, James KS, Winecoff DK, Kirchherr JL, Archin NM, Browne EP, Strahl BD, Margolis DM, James LI. Evaluation of EED Inhibitors as a Class of PRC2-Targeted Small Molecules for HIV Latency Reversal. ACS Infect Dis 2020; 6:1719-1733. [PMID: 32347704 PMCID: PMC7359025 DOI: 10.1021/acsinfecdis.9b00514] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
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A hallmark of human
immunodeficiency type-1 (HIV) infection is
the integration of the viral genome into host chromatin, resulting
in a latent reservoir that persists despite antiviral therapy or immune
response. Thus, key priorities toward eradication of HIV infection
are to understand the mechanisms that allow HIV latency and to develop
latency reversal agents (LRAs) that can facilitate the clearance of
latently infected cells. The repressive H3K27me3 histone mark, catalyzed
by the PRC2 complex, plays a pivotal role in transcriptional repression
at the viral promoter in both cell line and primary CD4+ T cell models
of latency. EZH2 inhibitors which block H3K27 methylation have been
shown to act as LRAs, suggesting other PRC2 components could also
be potential targets for latency reversal. EED, a core component of
PRC2, ensures the propagation of H3K27me3 by allosterically activating
EZH2 methyltransferase activity. Therefore, we sought to investigate
if inhibition of EED would also reverse latency. Inhibitors of EED,
EED226 and A-395, demonstrated latency reversal activity as single
agents, and this activity was further enhanced when used in combination
with other known LRAs. Loss of H3K27me3 following EED inhibition significantly
increased the levels of H3K27 acetylation globally and at the HIV
LTR. These results further confirm that PRC2 mediated repression plays
a significant role in the maintenance of HIV latency and suggest that
EED may serve as a promising new target for LRA development.
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Affiliation(s)
- Anne-Marie W. Turner
- UNC HIV Cure Center, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, North Carolina 27599, United States
- Department of Medicine, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, North Carolina 27599, United States
| | - Raghuvar Dronamraju
- Department of Biochemistry & Biophysics, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, North Carolina 27599, United States
| | - Frances Potjewyd
- Center for Integrative Chemical Biology and Drug Discovery, Division of Chemical Biology and Medicinal Chemistry, Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States
| | - Katherine S. James
- UNC HIV Cure Center, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, North Carolina 27599, United States
| | - Daniel K. Winecoff
- UNC HIV Cure Center, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, North Carolina 27599, United States
| | - Jennifer L. Kirchherr
- UNC HIV Cure Center, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, North Carolina 27599, United States
| | - Nancie M. Archin
- UNC HIV Cure Center, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, North Carolina 27599, United States
- Department of Medicine, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, North Carolina 27599, United States
| | - Edward P. Browne
- UNC HIV Cure Center, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, North Carolina 27599, United States
- Department of Medicine, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, North Carolina 27599, United States
| | - Brian D. Strahl
- Department of Biochemistry & Biophysics, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, North Carolina 27599, United States
| | - David M. Margolis
- UNC HIV Cure Center, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, North Carolina 27599, United States
- Department of Medicine, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, North Carolina 27599, United States
- Department of Epidemiology, University of North Carolina at Chapel Hill School of Public Health, Chapel Hill, North Carolina 27599, United States
- Department of Microbiology and Immunology, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, North Carolina 27599, United States
| | - Lindsey I. James
- UNC HIV Cure Center, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, North Carolina 27599, United States
- Center for Integrative Chemical Biology and Drug Discovery, Division of Chemical Biology and Medicinal Chemistry, Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States
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Shukla A, Ramirez NGP, D’Orso I. HIV-1 Proviral Transcription and Latency in the New Era. Viruses 2020; 12:v12050555. [PMID: 32443452 PMCID: PMC7291205 DOI: 10.3390/v12050555] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2020] [Revised: 05/06/2020] [Accepted: 05/12/2020] [Indexed: 12/11/2022] Open
Abstract
Three decades of extensive work in the HIV field have revealed key viral and host cell factors controlling proviral transcription. Various models of transcriptional regulation have emerged based on the collective information from in vitro assays and work in both immortalized and primary cell-based models. Here, we provide a recount of the past and current literature, highlight key regulatory aspects, and further describe potential limitations of previous studies. We particularly delve into critical steps of HIV gene expression including the role of the integration site, nucleosome positioning and epigenomics, and the transition from initiation to pausing and pause release. We also discuss open questions in the field concerning the generality of previous regulatory models to the control of HIV transcription in patients under suppressive therapy, including the role of the heterogeneous integration landscape, clonal expansion, and bottlenecks to eradicate viral persistence. Finally, we propose that building upon previous discoveries and improved or yet-to-be discovered technologies will unravel molecular mechanisms of latency establishment and reactivation in a “new era”.
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Mori L, Valente ST. Key Players in HIV-1 Transcriptional Regulation: Targets for a Functional Cure. Viruses 2020; 12:E529. [PMID: 32403278 PMCID: PMC7291152 DOI: 10.3390/v12050529] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2020] [Revised: 05/07/2020] [Accepted: 05/08/2020] [Indexed: 12/13/2022] Open
Abstract
HIV-1 establishes a life-long infection when proviral DNA integrates into the host genome. The provirus can then either actively transcribe RNA or enter a latent state, without viral production. The switch between these two states is governed in great part by the viral protein, Tat, which promotes RNA transcript elongation. Latency is also influenced by the availability of host transcription factors, integration site, and the surrounding chromatin environment. The latent reservoir is established in the first few days of infection and serves as the source of viral rebound upon treatment interruption. Despite effective suppression of HIV-1 replication by antiretroviral therapy (ART), to below the detection limit, ART is ineffective at reducing the latent reservoir size. Elimination of this reservoir has become a major goal of the HIV-1 cure field. However, aside from the ideal total HIV-1 eradication from the host genome, an HIV-1 remission or functional cure is probably more realistic. The "block-and-lock" approach aims at the transcriptional silencing of the viral reservoir, to render suppressed HIV-1 promoters extremely difficult to reactivate from latency. There are unfortunately no clinically available HIV-1 specific transcriptional inhibitors. Understanding the mechanisms that regulate latency is expected to provide novel targets to be explored in cure approaches.
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Affiliation(s)
| | - Susana T. Valente
- Department of Immunology and Microbiology, The Scripps Research Institute, 130 Scripps Way, Jupiter, FL 33458, USA;
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PIWIL4 Maintains HIV-1 Latency by Enforcing Epigenetically Suppressive Modifications on the 5' Long Terminal Repeat. J Virol 2020; 94:JVI.01923-19. [PMID: 32161174 DOI: 10.1128/jvi.01923-19] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2019] [Accepted: 02/21/2020] [Indexed: 02/07/2023] Open
Abstract
Although substantial progress has been made in depicting the molecular pathogenesis of human immunodeficiency virus type 1 (HIV-1) infection, the comprehensive mechanism of HIV-1 latency and the most promising therapeutic strategies to effectively reactivate the HIV-1 latent reservoir to achieve a functional cure for AIDS remain to be systematically illuminated. Here, we demonstrated that piwi (P element-induced Wimpy)-like RNA-mediated gene silencing 4 (PIWIL4) played an important role in suppressing HIV-1 transcription and contributed to the latency state in HIV-1-infected cells through its recruitment of various suppressive factors, including heterochromatin protein 1α/β/γ, SETDB1, and HDAC4. The knockdown of PIWIL4 enhanced HIV-1 transcription and reversed HIV-1 latency in both HIV-1 latently infected Jurkat T cells and primary CD4+ T lymphocytes and resting CD4+ T lymphocytes from HIV-1-infected individuals on suppressive combined antiretroviral therapy (cART). Furthermore, in the absence of PIWIL4, HIV-1 latently infected Jurkat T cells were more sensitive to reactivation with vorinostat (suberoylanilide hydroxamic acid, or SAHA), JQ1, or prostratin. These findings indicated that PIWIL4 promotes HIV-1 latency by imposing repressive marks at the HIV-1 5' long terminal repeat. Thus, the manipulation of PIWIL4 could be a novel strategy for developing promising latency-reversing agents (LRAs).IMPORTANCE HIV-1 latency is systematically modulated by host factors and viral proteins. During this process, the suppression of HIV-1 transcription plays an essential role in promoting HIV-1 latency. In this study, we found that PIWIL4 repressed HIV-1 promoter activity and maintained HIV-1 latency. In particular, we report that PIWIL4 can regulate gene expression through its association with the suppressive activity of HDAC4. Therefore, we have identified a new function for PIWIL4: it is not only a suppressor of endogenous retrotransposons but also plays an important role in inhibiting transcription and leading to latent infection of HIV-1, a well-known exogenous retrovirus. Our results also indicate a novel therapeutic target to reactivate the HIV-1 latent reservoir.
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50
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Margolis DM, Archin NM, Cohen MS, Eron JJ, Ferrari G, Garcia JV, Gay CL, Goonetilleke N, Joseph SB, Swanstrom R, Turner AMW, Wahl A. Curing HIV: Seeking to Target and Clear Persistent Infection. Cell 2020; 181:189-206. [PMID: 32220311 DOI: 10.1016/j.cell.2020.03.005] [Citation(s) in RCA: 96] [Impact Index Per Article: 24.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2020] [Revised: 03/03/2020] [Accepted: 03/03/2020] [Indexed: 12/14/2022]
Abstract
Human immunodeficiency virus type 1 (HIV-1) infection persists despite years of antiretroviral therapy (ART). To remove the stigma and burden of chronic infection, approaches to eradicate or cure HIV infection are desired. Attempts to augment ART with therapies that reverse viral latency, paired with immunotherapies to clear infection, have advanced into the clinic, but the field is still in its infancy. We review foundational studies and highlight new insights in HIV cure research. Together with advances in ART delivery and HIV prevention strategies, future therapies that clear HIV infection may relieve society of the affliction of the HIV pandemic.
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Affiliation(s)
- David M Margolis
- UNC HIV Cure Center, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, NC 27599, USA; Department of Medicine, Division of Infectious Diseases, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, NC 27599, USA; Department of Microbiology and Immunology, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, NC 27599, USA; Department of Epidemiology, University of North Carolina at Chapel Hill School of Public Health, Chapel Hill, NC 27599, USA.
| | - Nancie M Archin
- UNC HIV Cure Center, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, NC 27599, USA; Department of Medicine, Division of Infectious Diseases, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, NC 27599, USA
| | - Myron S Cohen
- Department of Medicine, Division of Infectious Diseases, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, NC 27599, USA; Institute for Global Health and Infectious Diseases, University of North Carolina, Chapel Hill, NC 27599, USA
| | - Joseph J Eron
- UNC HIV Cure Center, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, NC 27599, USA; Department of Medicine, Division of Infectious Diseases, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, NC 27599, USA
| | - Guido Ferrari
- Department of Surgery and Duke Human Vaccine Institute, Duke University Medical Center, Durham, NC 27710, USA
| | - J Victor Garcia
- International Center for the Advancement of Translational Science, Division of Infectious Diseases, Department of Medicine, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, NC 27599, USA; Center for AIDS Research, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, NC 27599, USA
| | - Cynthia L Gay
- UNC HIV Cure Center, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, NC 27599, USA; Department of Medicine, Division of Infectious Diseases, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, NC 27599, USA
| | - Nilu Goonetilleke
- UNC HIV Cure Center, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, NC 27599, USA; Department of Microbiology and Immunology, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, NC 27599, USA
| | - Sarah B Joseph
- UNC HIV Cure Center, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, NC 27599, USA; Department of Microbiology and Immunology, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, NC 27599, USA; Center for AIDS Research, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, NC 27599, USA; Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Ronald Swanstrom
- Center for AIDS Research, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, NC 27599, USA; Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA; Department of Biochemistry & Biophysics, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, NC 27599, USA
| | - Anne-Marie W Turner
- UNC HIV Cure Center, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, NC 27599, USA; Department of Medicine, Division of Infectious Diseases, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, NC 27599, USA
| | - Angela Wahl
- International Center for the Advancement of Translational Science, Division of Infectious Diseases, Department of Medicine, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, NC 27599, USA; Center for AIDS Research, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, NC 27599, USA
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