51
|
Srinivasachar Badarinarayan S, Shcherbakova I, Langer S, Koepke L, Preising A, Hotter D, Kirchhoff F, Sparrer KMJ, Schotta G, Sauter D. HIV-1 infection activates endogenous retroviral promoters regulating antiviral gene expression. Nucleic Acids Res 2020; 48:10890-10908. [PMID: 33021676 PMCID: PMC7641743 DOI: 10.1093/nar/gkaa832] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2020] [Revised: 09/14/2020] [Accepted: 09/17/2020] [Indexed: 12/13/2022] Open
Abstract
Although endogenous retroviruses (ERVs) are known to harbor cis-regulatory elements, their role in modulating cellular immune responses remains poorly understood. Using an RNA-seq approach, we show that several members of the ERV9 lineage, particularly LTR12C elements, are activated upon HIV-1 infection of primary CD4+ T cells. Intriguingly, HIV-1-induced ERVs harboring transcription start sites are primarily found in the vicinity of immunity genes. For example, HIV-1 infection activates LTR12C elements upstream of the interferon-inducible genes GBP2 and GBP5 that encode for broad-spectrum antiviral factors. Reporter assays demonstrated that these LTR12C elements drive gene expression in primary CD4+ T cells. In line with this, HIV-1 infection triggered the expression of a unique GBP2 transcript variant by activating a cryptic transcription start site within LTR12C. Furthermore, stimulation with HIV-1-induced cytokines increased GBP2 and GBP5 expression in human cells, but not in macaque cells that naturally lack the GBP5 gene and the LTR12C element upstream of GBP2. Finally, our findings suggest that GBP2 and GBP5 have already been active against ancient viral pathogens as they suppress the maturation of the extinct retrovirus HERV-K (HML-2). In summary, our findings uncover how human cells can exploit remnants of once-infectious retroviruses to regulate antiviral gene expression.
Collapse
Affiliation(s)
| | - Irina Shcherbakova
- Molecular Biology Division, Biomedical Center, Ludwig-Maximilians-University Munich, Planegg-Martinsried 82152, Germany
| | - Simon Langer
- Institute of Molecular Virology, Ulm University Medical Center, Ulm 89081, Germany.,Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA 92037, USA
| | - Lennart Koepke
- Institute of Molecular Virology, Ulm University Medical Center, Ulm 89081, Germany
| | - Andrea Preising
- Institute of Molecular Virology, Ulm University Medical Center, Ulm 89081, Germany
| | - Dominik Hotter
- Institute of Molecular Virology, Ulm University Medical Center, Ulm 89081, Germany
| | - Frank Kirchhoff
- Institute of Molecular Virology, Ulm University Medical Center, Ulm 89081, Germany
| | | | - Gunnar Schotta
- Molecular Biology Division, Biomedical Center, Ludwig-Maximilians-University Munich, Planegg-Martinsried 82152, Germany
| | - Daniel Sauter
- Institute of Molecular Virology, Ulm University Medical Center, Ulm 89081, Germany
| |
Collapse
|
52
|
Li W, Singh PK, Sowd GA, Bedwell GJ, Jang S, Achuthan V, Oleru AV, Wong D, Fadel HJ, Lee K, KewalRamani VN, Poeschla EM, Herschhorn A, Engelman AN. CPSF6-Dependent Targeting of Speckle-Associated Domains Distinguishes Primate from Nonprimate Lentiviral Integration. mBio 2020; 11:e02254-20. [PMID: 32994325 PMCID: PMC7527728 DOI: 10.1128/mbio.02254-20] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2020] [Accepted: 08/28/2020] [Indexed: 12/19/2022] Open
Abstract
Lentiviral DNA integration favors transcriptionally active chromatin. We previously showed that the interaction of human immunodeficiency virus type 1 (HIV-1) capsid with cleavage and polyadenylation specificity factor 6 (CPSF6) localizes viral preintegration complexes (PICs) to nuclear speckles for integration into transcriptionally active speckle-associated domains (SPADs). In the absence of the capsid-CPSF6 interaction, PICs uncharacteristically accumulate at the nuclear periphery and target heterochromatic lamina-associated domains (LADs) for integration. The integrase-binding protein lens epithelium-derived growth factor (LEDGF)/p75 in contrast to CPSF6 predominantly functions to direct HIV-1 integration to interior regions of transcription units. Though CPSF6 and LEDGF/p75 can reportedly interact with the capsid and integrase proteins of both primate and nonprimate lentiviruses, the extents to which these different viruses target SPADs versus LADs, as well as their dependencies on CPSF6 and LEDGF/p75 for integration targeting, are largely unknown. Here, we mapped 5,489,157 primate and nonprimate lentiviral integration sites in HEK293T and Jurkat T cells as well as derivative cells that were knocked out or knocked down for host factor expression. Despite marked preferences of all lentiviruses to target genes for integration, nonprimate lentiviruses only marginally favored SPADs, with corresponding upticks in LAD-proximal integration. While LEDGF/p75 knockout disrupted the intragenic integration profiles of all lentiviruses similarly, CPSF6 depletion specifically counteracted SPAD integration targeting by primate lentiviruses. CPSF6 correspondingly failed to appreciably interact with nonprimate lentiviral capsids. We conclude that primate lentiviral capsid proteins evolved to interact with CPSF6 to optimize PIC localization for integration into transcriptionally active SPADs.IMPORTANCE Integration is the defining step of the retroviral life cycle and underlies the inability to cure HIV/AIDS through the use of intensified antiviral therapy. The reservoir of latent, replication-competent proviruses that forms early during HIV infection reseeds viremia when patients discontinue medication. HIV cure research is accordingly focused on the factors that guide provirus formation and associated chromatin environments that regulate transcriptional reactivation, and studies of orthologous infectious agents such as nonprimate lentiviruses can inform basic principles of HIV biology. HIV-1 utilizes the integrase-binding protein LEDGF/p75 and the capsid interactor CPSF6 to target speckle-associated domains (SPADs) for integration. However, the extent to which these two host proteins regulate integration of other lentiviruses is largely unknown. Here, we mapped millions of retroviral integration sites in cell lines that were depleted for LEDGF/p75 and/or CPSF6. Our results reveal that primate lentiviruses uniquely target SPADs for integration in a CPSF6-dependent manner.
Collapse
Affiliation(s)
- Wen Li
- Department of Cancer Immunology and Virology, Dana-Farber Cancer Institute, Boston, Massachusetts, USA
- Department of Medicine, Harvard Medical School, Boston, Massachusetts, USA
| | - Parmit K Singh
- Department of Cancer Immunology and Virology, Dana-Farber Cancer Institute, Boston, Massachusetts, USA
- Department of Medicine, Harvard Medical School, Boston, Massachusetts, USA
| | - Gregory A Sowd
- Department of Cancer Immunology and Virology, Dana-Farber Cancer Institute, Boston, Massachusetts, USA
- Department of Medicine, Harvard Medical School, Boston, Massachusetts, USA
| | - Gregory J Bedwell
- Department of Cancer Immunology and Virology, Dana-Farber Cancer Institute, Boston, Massachusetts, USA
- Department of Medicine, Harvard Medical School, Boston, Massachusetts, USA
| | - Sooin Jang
- Department of Cancer Immunology and Virology, Dana-Farber Cancer Institute, Boston, Massachusetts, USA
- Department of Medicine, Harvard Medical School, Boston, Massachusetts, USA
| | - Vasudevan Achuthan
- Department of Cancer Immunology and Virology, Dana-Farber Cancer Institute, Boston, Massachusetts, USA
- Department of Medicine, Harvard Medical School, Boston, Massachusetts, USA
| | - Amarachi V Oleru
- Department of Cancer Immunology and Virology, Dana-Farber Cancer Institute, Boston, Massachusetts, USA
| | - Doris Wong
- Department of Cancer Immunology and Virology, Dana-Farber Cancer Institute, Boston, Massachusetts, USA
| | - Hind J Fadel
- Department of Internal Medicine, Mayo Clinic, Rochester, Minnesota, USA
| | - KyeongEun Lee
- Basic Research Laboratory, Center for Cancer Research, National Cancer Institute, Frederick, Maryland, USA
| | - Vineet N KewalRamani
- Basic Research Laboratory, Center for Cancer Research, National Cancer Institute, Frederick, Maryland, USA
| | - Eric M Poeschla
- Division of Infectious Diseases, University of Colorado Denver School of Medicine, Aurora, Colorado, USA
| | - Alon Herschhorn
- Department of Cancer Immunology and Virology, Dana-Farber Cancer Institute, Boston, Massachusetts, USA
- Department of Medicine, Harvard Medical School, Boston, Massachusetts, USA
| | - Alan N Engelman
- Department of Cancer Immunology and Virology, Dana-Farber Cancer Institute, Boston, Massachusetts, USA
- Department of Medicine, Harvard Medical School, Boston, Massachusetts, USA
| |
Collapse
|
53
|
Rocha S, Hendrix J, Borrenberghs D, Debyser Z, Hofkens J. Imaging the Replication of Single Viruses: Lessons Learned from HIV and Future Challenges To Overcome. ACS NANO 2020; 14:10775-10783. [PMID: 32820634 DOI: 10.1021/acsnano.0c06369] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
The molecular composition of viral particles indicates that a single virion is capable of initiating an infection. However, the majority of viruses that come into contact with cells fails to infect them. Understanding what makes one viral particle more successful than others requires visualizing the infection process directly in living cells, one virion at a time. In this Perspective, we explain how single-virus imaging using fluorescence microscopy can provide answers to unsolved questions in virology. We discuss fluorescent labeling of virus particles, resolution at the subviral and molecular levels, tracking in living cells, and imaging of interactions between viral and host proteins. We end this Perspective with a set of remaining questions in understanding the life cycle of retroviruses and how imaging a single virus can help researchers address these questions. Although we use examples from the HIV field, these methods are of value for the study of other viruses as well.
Collapse
Affiliation(s)
- Susana Rocha
- Molecular Imaging and Photonics, Chemistry Department, KU Leuven, B-3001 Heverlee, Flanders, Belgium
| | - Jelle Hendrix
- Molecular Imaging and Photonics, Chemistry Department, KU Leuven, B-3001 Heverlee, Flanders, Belgium
- Dynamic Bioimaging Lab, Advanced Optical Microscopy Centre and Biomedical Research Institute (BIOMED), Hasselt University, B-3590 Diepenbeek, Flanders, Belgium
| | - Doortje Borrenberghs
- Molecular Imaging and Photonics, Chemistry Department, KU Leuven, B-3001 Heverlee, Flanders, Belgium
| | - Zeger Debyser
- Laboratory for Molecular Virology and Gene Therapy, Department of Pharmaceutical and Pharmacological Sciences, KU Leuven, B-3001 Heverlee, Flanders, Belgium
| | - Johan Hofkens
- Molecular Imaging and Photonics, Chemistry Department, KU Leuven, B-3001 Heverlee, Flanders, Belgium
- Max Planck Institute for Polymer Research, 55128 Mainz, Germany
| |
Collapse
|
54
|
Jiang C, Lian X, Gao C, Sun X, Einkauf KB, Chevalier JM, Chen SMY, Hua S, Rhee B, Chang K, Blackmer JE, Osborn M, Peluso MJ, Hoh R, Somsouk M, Milush J, Bertagnolli LN, Sweet SE, Varriale JA, Burbelo PD, Chun TW, Laird GM, Serrao E, Engelman AN, Carrington M, Siliciano RF, Siliciano JM, Deeks SG, Walker BD, Lichterfeld M, Yu XG. Distinct viral reservoirs in individuals with spontaneous control of HIV-1. Nature 2020; 585:261-267. [PMID: 32848246 PMCID: PMC7837306 DOI: 10.1038/s41586-020-2651-8] [Citation(s) in RCA: 218] [Impact Index Per Article: 54.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2019] [Accepted: 07/15/2020] [Indexed: 02/01/2023]
Abstract
Sustained, drug-free control of HIV-1 replication is naturally achieved in less than 0.5% of infected individuals (here termed 'elite controllers'), despite the presence of a replication-competent viral reservoir1. Inducing such an ability to spontaneously maintain undetectable plasma viraemia is a major objective of HIV-1 cure research, but the characteristics of proviral reservoirs in elite controllers remain to be determined. Here, using next-generation sequencing of near-full-length single HIV-1 genomes and corresponding chromosomal integration sites, we show that the proviral reservoirs of elite controllers frequently consist of oligoclonal to near-monoclonal clusters of intact proviral sequences. In contrast to individuals treated with long-term antiretroviral therapy, intact proviral sequences from elite controllers were integrated at highly distinct sites in the human genome and were preferentially located in centromeric satellite DNA or in Krüppel-associated box domain-containing zinc finger genes on chromosome 19, both of which are associated with heterochromatin features. Moreover, the integration sites of intact proviral sequences from elite controllers showed an increased distance to transcriptional start sites and accessible chromatin of the host genome and were enriched in repressive chromatin marks. These data suggest that a distinct configuration of the proviral reservoir represents a structural correlate of natural viral control, and that the quality, rather than the quantity, of viral reservoirs can be an important distinguishing feature for a functional cure of HIV-1 infection. Moreover, in one elite controller, we were unable to detect intact proviral sequences despite analysing more than 1.5 billion peripheral blood mononuclear cells, which raises the possibility that a sterilizing cure of HIV-1 infection, which has previously been observed only following allogeneic haematopoietic stem cell transplantation2,3, may be feasible in rare instances.
Collapse
Affiliation(s)
- Chenyang Jiang
- Ragon Institute of MGH, MIT and Harvard, Cambridge, MA, USA
- Infectious Disease Division, Brigham and Women's Hospital, Boston, MA, USA
| | - Xiaodong Lian
- Ragon Institute of MGH, MIT and Harvard, Cambridge, MA, USA
- Infectious Disease Division, Brigham and Women's Hospital, Boston, MA, USA
| | - Ce Gao
- Ragon Institute of MGH, MIT and Harvard, Cambridge, MA, USA
| | - Xiaoming Sun
- Ragon Institute of MGH, MIT and Harvard, Cambridge, MA, USA
| | - Kevin B Einkauf
- Ragon Institute of MGH, MIT and Harvard, Cambridge, MA, USA
- Infectious Disease Division, Brigham and Women's Hospital, Boston, MA, USA
| | - Joshua M Chevalier
- Ragon Institute of MGH, MIT and Harvard, Cambridge, MA, USA
- Infectious Disease Division, Brigham and Women's Hospital, Boston, MA, USA
| | | | - Stephane Hua
- Ragon Institute of MGH, MIT and Harvard, Cambridge, MA, USA
| | - Ben Rhee
- Ragon Institute of MGH, MIT and Harvard, Cambridge, MA, USA
- Infectious Disease Division, Brigham and Women's Hospital, Boston, MA, USA
| | - Kaylee Chang
- Ragon Institute of MGH, MIT and Harvard, Cambridge, MA, USA
| | | | - Matthew Osborn
- Ragon Institute of MGH, MIT and Harvard, Cambridge, MA, USA
| | - Michael J Peluso
- Department of Medicine, University of California at San Francisco, San Francisco, CA, USA
| | - Rebecca Hoh
- Department of Medicine, University of California at San Francisco, San Francisco, CA, USA
| | - Ma Somsouk
- Department of Medicine, University of California at San Francisco, San Francisco, CA, USA
| | - Jeffrey Milush
- Department of Medicine, University of California at San Francisco, San Francisco, CA, USA
| | - Lynn N Bertagnolli
- Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Sarah E Sweet
- Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Joseph A Varriale
- Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Peter D Burbelo
- Dental Clinical Research Core, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD, USA
| | - Tae-Wook Chun
- National Institute of Allergies and Infectious Diseases, Bethesda, MD, USA
| | | | - Erik Serrao
- Department of Cancer Immunology and Virology, Dana-Farber Cancer Institute, Boston, MA, USA
- Department of Medicine, Harvard Medical School, Boston, MA, USA
| | - Alan N Engelman
- Department of Cancer Immunology and Virology, Dana-Farber Cancer Institute, Boston, MA, USA
- Department of Medicine, Harvard Medical School, Boston, MA, USA
| | - Mary Carrington
- Ragon Institute of MGH, MIT and Harvard, Cambridge, MA, USA
- Basic Science Program, Frederick National Laboratory for Cancer Research, Frederick, MD, USA
| | - Robert F Siliciano
- Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA
- Howard Hughes Medical Institute, Chevy Chase, MD, USA
| | - Janet M Siliciano
- Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA
- Howard Hughes Medical Institute, Chevy Chase, MD, USA
| | - Steven G Deeks
- Department of Medicine, University of California at San Francisco, San Francisco, CA, USA
| | - Bruce D Walker
- Ragon Institute of MGH, MIT and Harvard, Cambridge, MA, USA
- Howard Hughes Medical Institute, Chevy Chase, MD, USA
- Institute for Medical Engineering and Sciences, Massachusetts Institute of Technology, Cambridge, MA, USA
- Department of Biology, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Mathias Lichterfeld
- Ragon Institute of MGH, MIT and Harvard, Cambridge, MA, USA
- Infectious Disease Division, Brigham and Women's Hospital, Boston, MA, USA
- Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | - Xu G Yu
- Ragon Institute of MGH, MIT and Harvard, Cambridge, MA, USA.
- Infectious Disease Division, Brigham and Women's Hospital, Boston, MA, USA.
| |
Collapse
|
55
|
Laukkanen S, Oksa L, Nikkilä A, Lahnalampi M, Parikka M, Seki M, Takita J, Degerman S, de Bock CE, Heinäniemi M, Lohi O. SIX6 is a TAL1-regulated transcription factor in T-ALL and associated with inferior outcome. Leuk Lymphoma 2020; 61:3089-3100. [PMID: 32835548 DOI: 10.1080/10428194.2020.1804560] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
T-cell acute lymphoblastic leukemia (T-ALL) is a hematological malignancy driven by abnormal activity of transcription factors. Here we report an aberrant expression of the developmental transcription factor SIX6 in the TAL1-subtype of T-ALL. Our results demonstrate that the binding of TAL1 and GATA3 transcription factors into an upstream enhancer element directly regulates SIX6 expression. High expression of SIX6 was associated with inferior event-free survival within three independent patient cohorts. At a functional level, CRISPR-Cas9-mediated knockout of the SIX6 gene in TAL1 positive Jurkat cells induced changes in genes associated with the mTOR-, K-RAS-, and TNFα-related molecular signatures but did not impair cell proliferation or viability. There was also no acceleration of T-ALL development within a Myc driven zebrafish tumor model in vivo. Taken together, our results show that SIX6 belongs to the TAL1 regulatory gene network in T-ALL but is alone insufficient to influence the development or maintenance of T-ALL.
Collapse
Affiliation(s)
- Saara Laukkanen
- Faculty of Medicine and Health Technology, Tampere Center for Child Health Research, Tampere University, Tampere, Finland
| | - Laura Oksa
- Faculty of Medicine and Health Technology, Tampere Center for Child Health Research, Tampere University, Tampere, Finland
| | - Atte Nikkilä
- Faculty of Medicine and Health Technology, Tampere Center for Child Health Research, Tampere University, Tampere, Finland
| | - Mari Lahnalampi
- The Institute of Biomedicine, University of Eastern Finland, Kuopio, Finland
| | - Mataleena Parikka
- Faculty of Medicine and Health Technology, BioMediTech, Tampere University, Tampere, Finland.,Oral and Maxillofacial Unit, Tampere University Hospital, Tampere, Finland
| | - Masafumi Seki
- Department of Cell and Molecular Biology, Karolinska Institutet, Solna, Sweden
| | - Junko Takita
- Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Sofie Degerman
- Department of Medical Biosciences and Department of Clinical Microbiology, Umeå University, Umeå, Sweden
| | - Charles E de Bock
- Children's Cancer Institute, Lowy Cancer Research Centre, Sydney, Australia.,School of Women's and Children's Health, University of New South Wales Sydney, Sydney, Australia
| | - Merja Heinäniemi
- The Institute of Biomedicine, University of Eastern Finland, Kuopio, Finland
| | - Olli Lohi
- Faculty of Medicine and Health Technology, Tampere Center for Child Health Research, Tampere University, Tampere, Finland.,Tays Cancer Centre, Tampere University Hospital, Tampere, Finland
| |
Collapse
|
56
|
Francis AC, Marin M, Singh PK, Achuthan V, Prellberg MJ, Palermino-Rowland K, Lan S, Tedbury PR, Sarafianos SG, Engelman AN, Melikyan GB. HIV-1 replication complexes accumulate in nuclear speckles and integrate into speckle-associated genomic domains. Nat Commun 2020; 11:3505. [PMID: 32665593 PMCID: PMC7360574 DOI: 10.1038/s41467-020-17256-8] [Citation(s) in RCA: 74] [Impact Index Per Article: 18.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2019] [Accepted: 06/19/2020] [Indexed: 12/12/2022] Open
Abstract
The early steps of HIV-1 infection, such as uncoating, reverse transcription, nuclear import, and transport to integration sites are incompletely understood. Here, we imaged nuclear entry and transport of HIV-1 replication complexes in cell lines, primary monocyte-derived macrophages (MDMs) and CD4+ T cells. We show that viral replication complexes traffic to and accumulate within nuclear speckles and that these steps precede the completion of viral DNA synthesis. HIV-1 transport to nuclear speckles is dependent on the interaction of the capsid proteins with host cleavage and polyadenylation specificity factor 6 (CPSF6), which is also required to stabilize the association of the viral replication complexes with nuclear speckles. Importantly, integration site analyses reveal a strong preference for HIV-1 to integrate into speckle-associated genomic domains. Collectively, our results demonstrate that nuclear speckles provide an architectural basis for nuclear homing of HIV-1 replication complexes and subsequent integration into associated genomic loci. Early steps of HIV infection of primary human cells remain poorly understood. Here, Francis et al. show that early viral replication complexes accumulate within nuclear speckles, in reliance on viral capsid/host CPSF6 interactions, and preferentially integrate in speckle-associated genomic domains.
Collapse
Affiliation(s)
- Ashwanth C Francis
- Division of Infectious Diseases, Department of Pediatrics, Emory University School of Medicine, Atlanta, GA, 30322, USA.
| | - Mariana Marin
- Division of Infectious Diseases, Department of Pediatrics, Emory University School of Medicine, Atlanta, GA, 30322, USA
| | - Parmit K Singh
- Department of Cancer Immunology and Virology, Dana-Farber Cancer Institute, Boston, MA, 02115, USA.,Department of Medicine, Harvard Medical School, Boston, MA, 02115, USA
| | - Vasudevan Achuthan
- Department of Cancer Immunology and Virology, Dana-Farber Cancer Institute, Boston, MA, 02115, USA.,Department of Medicine, Harvard Medical School, Boston, MA, 02115, USA
| | - Mathew J Prellberg
- Division of Infectious Diseases, Department of Pediatrics, Emory University School of Medicine, Atlanta, GA, 30322, USA
| | - Kristina Palermino-Rowland
- Division of Infectious Diseases, Department of Pediatrics, Emory University School of Medicine, Atlanta, GA, 30322, USA
| | - Shuiyun Lan
- Laboratory of Biochemical Pharmacology, Department of Pediatrics, Emory University School of Medicine, Atlanta, GA, 30322, USA
| | - Philip R Tedbury
- Laboratory of Biochemical Pharmacology, Department of Pediatrics, Emory University School of Medicine, Atlanta, GA, 30322, USA
| | - Stefan G Sarafianos
- Laboratory of Biochemical Pharmacology, Department of Pediatrics, Emory University School of Medicine, Atlanta, GA, 30322, USA
| | - Alan N Engelman
- Department of Cancer Immunology and Virology, Dana-Farber Cancer Institute, Boston, MA, 02115, USA.,Department of Medicine, Harvard Medical School, Boston, MA, 02115, USA
| | - Gregory B Melikyan
- Division of Infectious Diseases, Department of Pediatrics, Emory University School of Medicine, Atlanta, GA, 30322, USA. .,Children's Healthcare of Atlanta, Atlanta, GA, 30322, USA.
| |
Collapse
|
57
|
Ivanov S, Lagunin A, Filimonov D, Tarasova O. Network-Based Analysis of OMICs Data to Understand the HIV-Host Interaction. Front Microbiol 2020; 11:1314. [PMID: 32625189 PMCID: PMC7311653 DOI: 10.3389/fmicb.2020.01314] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2020] [Accepted: 05/25/2020] [Indexed: 12/22/2022] Open
Abstract
The interaction of human immunodeficiency virus with human cells is responsible for all stages of the viral life cycle, from the infection of CD4+ cells to reverse transcription, integration, and the assembly of new viral particles. To date, a large amount of OMICs data as well as information from functional genomics screenings regarding the HIV–host interaction has been accumulated in the literature and in public databases. We processed databases containing HIV–host interactions and found 2910 HIV-1-human protein-protein interactions, mostly related to viral group M subtype B, 137 interactions between human and HIV-1 coding and non-coding RNAs, essential for viral lifecycle and cell defense mechanisms, 232 transcriptomics, 27 proteomics, and 34 epigenomics HIV-related experiments. Numerous studies regarding network-based analysis of corresponding OMICs data have been published in recent years. We overview various types of molecular networks, which can be created using OMICs data, including HIV–human protein–protein interaction networks, co-expression networks, gene regulatory and signaling networks, and approaches for the analysis of their topology and dynamics. The network-based analysis can be used to determine the critical pathways and key proteins involved in the HIV life cycle, cellular and immune responses to infection, viral escape from host defense mechanisms, and mechanisms mediating different susceptibility of humans to infection. The proteins and pathways identified in these studies represent a basis for developing new anti-HIV therapeutic strategies such as new drugs preventing infection of CD4+ cells and viral replication, effective vaccines, “shock and kill” and “block and lock” approaches to cure latent infection.
Collapse
Affiliation(s)
- Sergey Ivanov
- Department of Bioinformatics, Institute of Biomedical Chemistry, Moscow, Russia.,Department of Bioinformatics, Pirogov Russian National Research Medical University, Moscow, Russia
| | - Alexey Lagunin
- Department of Bioinformatics, Institute of Biomedical Chemistry, Moscow, Russia.,Department of Bioinformatics, Pirogov Russian National Research Medical University, Moscow, Russia
| | - Dmitry Filimonov
- Department of Bioinformatics, Institute of Biomedical Chemistry, Moscow, Russia
| | - Olga Tarasova
- Department of Bioinformatics, Institute of Biomedical Chemistry, Moscow, Russia
| |
Collapse
|
58
|
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”.
Collapse
|
59
|
Key Players in HIV-1 Transcriptional Regulation: Targets for a Functional Cure. Viruses 2020; 12:v12050529. [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] [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.
Collapse
|
60
|
Tan Y, Li Y, Tang F. Oncogenic seRNA functional activation: a novel mechanism of tumorigenesis. Mol Cancer 2020; 19:74. [PMID: 32278350 PMCID: PMC7149907 DOI: 10.1186/s12943-020-01195-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2019] [Accepted: 03/30/2020] [Indexed: 02/06/2023] Open
Abstract
seRNA is a noncoding RNA (ncRNA) transcribed from active super-enhancer (SE), through which SE exerts biological functions and participates in various physiological and pathological processes. seRNA recruits cofactor, RNA polymerase II and mediator to constitute and stabilize chromatin loop SE and promoter region, which regulates target genes transcription. In tumorigenesis, DNA insertion, deletion, translocation, focal amplification and carcinogen factor mediate oncogenic SE generation, meanwhile, oncogenic SE transcribes into tumor-related seRNA, termed as oncogenic seRNA. Oncogenic seRNA participates in tumorigenesis through activating various signal-pathways. The recent reports showed that oncogenic seRNA implicates in a widespread range of cytopathological processes in cancer progression including cell proliferation, apoptosis, autophagy, epithelial-mesenchymal transition, extracellular matrix stiffness and angiogenesis. In this article, we comprehensively summarized seRNA’s characteristics and functions, and emphatically introduced inducible formation of oncogenic seRNA and its functional mechanisms. Lastly, some research strategies on oncogenic seRNA were introduced, and the perspectives on cancer therapy that targets oncogenic seRNA were also discussed.
Collapse
Affiliation(s)
- Yuan Tan
- Department of Clinical Laboratory and Hunan Key Laboratory of Oncotarget gene, Hunan Cancer Hospital & The affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, Changsha, 410013, China
| | - Yuejin Li
- Department of Clinical Laboratory and Hunan Key Laboratory of Oncotarget gene, Hunan Cancer Hospital & The affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, Changsha, 410013, China
| | - Faqing Tang
- Department of Clinical Laboratory and Hunan Key Laboratory of Oncotarget gene, Hunan Cancer Hospital & The affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, Changsha, 410013, China.
| |
Collapse
|
61
|
Bullock SL, Visa N, Pederson T. Meeting report - Nuclear and cytoplasmic molecular machines at work. J Cell Sci 2020; 133:133/7/jcs245134. [PMID: 32253357 DOI: 10.1242/jcs.245134] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
This report summarizes an international conference on molecular machines convened at New York University, Abu Dhabi by Piergiorgio Percipalle, George Shubeita and Serdal Kirmizialtin. The meeting was conceived around the epistemological question of what do we understand, or not understand (if we have open minds), about the degree to which cells operate by the individual actions of single enzymes or non-catalytic protein effectors, versus combinations of these in which their heterotypic association creates an entity that is more finely tuned and efficient - a machine. This theme was explored through a vivid series of talks, summarizing the latest findings on macromolecular complexes that operate in the nucleus or cytoplasm.
Collapse
Affiliation(s)
| | - Neus Visa
- Department of Molecular Biosciences, Wenner Gren Institute, Stockholm University, Stockholm 10 691, Sweden
| | - Thoru Pederson
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, MA 01605, USA
| |
Collapse
|
62
|
Wang W, Fasolino M, Cattau B, Goldman N, Kong W, Frederick MA, McCright SJ, Kiani K, Fraietta JA, Vahedi G. Joint profiling of chromatin accessibility and CAR-T integration site analysis at population and single-cell levels. Proc Natl Acad Sci U S A 2020; 117:5442-5452. [PMID: 32094195 PMCID: PMC7071901 DOI: 10.1073/pnas.1919259117] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Chimeric antigen receptor (CAR)-T immunotherapy has yielded impressive results in several B cell malignancies, establishing itself as a powerful means to redirect the natural properties of T lymphocytes. In this strategy, the T cell genome is modified by the integration of lentiviral vectors encoding CAR that direct tumor cell killing. However, this therapeutic approach is often limited by the extent of CAR-T cell expansion in vivo. A major outstanding question is whether or not CAR-T integration itself enhances the proliferative competence of individual T cells by rewiring their regulatory landscape. To address this question, it is critical to define the identity of an individual CAR-T cell and simultaneously chart where the CAR-T vector integrates into the genome. Here, we report the development of a method called EpiVIA (https://github.com/VahediLab/epiVIA) for the joint profiling of the chromatin accessibility and lentiviral integration site analysis at the population and single-cell levels. We validate our technique in clonal cells with previously defined integration sites and further demonstrate the ability to measure lentiviral integration sites and chromatin accessibility of host and viral genomes at the single-cell resolution in CAR-T cells. We anticipate that EpiVIA will enable the single-cell deconstruction of gene regulation during CAR-T therapy, leading to the discovery of cellular factors associated with durable treatment.
Collapse
Affiliation(s)
- Wenliang Wang
- Department of Genetics, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104
- Institute for Immunology, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104
- Epigenetics Institute, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104
- Institute for Diabetes, Obesity and Metabolism, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104
| | - Maria Fasolino
- Department of Genetics, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104
- Institute for Immunology, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104
- Epigenetics Institute, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104
- Institute for Diabetes, Obesity and Metabolism, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104
| | - Benjamin Cattau
- Department of Genetics, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104
- Institute for Immunology, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104
- Epigenetics Institute, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104
- Institute for Diabetes, Obesity and Metabolism, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104
| | - Naomi Goldman
- Department of Genetics, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104
- Institute for Immunology, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104
- Epigenetics Institute, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104
- Institute for Diabetes, Obesity and Metabolism, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104
| | - Weimin Kong
- Department of Microbiology, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104
- Abramson Family Cancer Center, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104
- Center for Cellular Immunotherapies, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104
| | - Megan A Frederick
- Department of Genetics, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104
- Institute for Immunology, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104
- Epigenetics Institute, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104
- Institute for Diabetes, Obesity and Metabolism, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104
| | - Sam J McCright
- Department of Genetics, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104
- Institute for Immunology, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104
- Epigenetics Institute, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104
- Institute for Diabetes, Obesity and Metabolism, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104
| | - Karun Kiani
- Department of Genetics, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104
- Institute for Immunology, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104
- Epigenetics Institute, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104
- Institute for Diabetes, Obesity and Metabolism, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104
| | - Joseph A Fraietta
- Department of Microbiology, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104
- Abramson Family Cancer Center, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104
- Center for Cellular Immunotherapies, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104
- Parker Institute for Cancer Immunotherapy, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104
| | - Golnaz Vahedi
- Department of Genetics, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104;
- Institute for Immunology, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104
- Epigenetics Institute, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104
- Institute for Diabetes, Obesity and Metabolism, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104
- Abramson Family Cancer Center, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104
| |
Collapse
|
63
|
Abstract
Chromosome organisation is increasingly recognised as an essential component of genome regulation, cell fate and cell health. Within the realm of transposable elements (TEs) however, the spatial information of how genomes are folded is still only rarely integrated in experimental studies or accounted for in modelling. Whilst polymer physics is recognised as an important tool to understand the mechanisms of genome folding, in this commentary we discuss its potential applicability to aspects of TE biology. Based on recent works on the relationship between genome organisation and TE integration, we argue that existing polymer models may be extended to create a predictive framework for the study of TE integration patterns. We suggest that these models may offer orthogonal and generic insights into the integration profiles (or "topography") of TEs across organisms. In addition, we provide simple polymer physics arguments and preliminary molecular dynamics simulations of TEs inserting into heterogeneously flexible polymers. By considering this simple model, we show how polymer folding and local flexibility may generically affect TE integration patterns. The preliminary discussion reported in this commentary is aimed to lay the foundations for a large-scale analysis of TE integration dynamics and topography as a function of the three-dimensional host genome.
Collapse
|
64
|
Chromatin maturation of the HIV-1 provirus in primary resting CD4+ T cells. PLoS Pathog 2020; 16:e1008264. [PMID: 31999790 PMCID: PMC6991963 DOI: 10.1371/journal.ppat.1008264] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2019] [Accepted: 12/09/2019] [Indexed: 12/14/2022] Open
Abstract
Human immunodeficiency virus type 1 (HIV-1) infection is a chronic condition, where viral DNA integrates into the genome. Latently infected cells form a persistent, heterogeneous reservoir that at any time can reactivate the integrated HIV-1. Here we confirmed that latently infected cells from HIV-1 positive study participants exhibited active HIV-1 transcription but without production of mature spliced mRNAs. To elucidate the mechanisms behind this we employed primary HIV-1 latency models to study latency establishment and maintenance. We characterized proviral transcription and chromatin development in cultures of resting primary CD4+ T-cells for four months after ex vivo HIV-1 infection. As heterochromatin (marked with H3K9me3 or H3K27me3) gradually stabilized, the provirus became less accessible with reduced activation potential. In a subset of infected cells, active marks (e.g. H3K27ac) and elongating RNAPII remained detectable at the latent provirus, despite prolonged proviral silencing. In many aspects, latent HIV-1 resembled an active enhancer in a subset of resting cells. The enhancer chromatin actively promoted latency and the enhancer-specific CBP/P300-inhibitor GNE049 was identified as a new latency reversal agent. The division of the latent reservoir according to distinct chromatin compositions with different reactivation potential enforces the notion that even though a relatively large set of cells contains the HIV-1 provirus, only a discrete subset is readily able to reactivate the provirus and spread the infection. HIV infection is a devastating disease affecting 35 million people worldwide. Current anti-retroviral treatment is highly effective and has made the HIV infection chronic. However, despite more effective treatments, the prospects of a cure are distant. The problem for an HIV cure is that, even though the virus particles are eradicated, the infected cells maintain the information of remake the virus. This information is integrated in the host cell as a provirus. The provirus switches between active and inactive states. Thereby, the infected cells evade both the immune system and death associated with massive viral production. We have characterized the composition of proviral chromatin and how it connects with transcription and viral production. In resting primary CD4+ T-cells, we follow the fate of the provirus starting at infection until latency is firmly established. Only in a fraction of intact proviruses were we able to reverse latency and that this was highly regulated by the chromatin composition. Whereas the proviruses encompassed in heterochromatin were refractory to activation, latent proviruses with “enhancer” characteristics were readily activated. Our study provides key insights as to detect the remaining HIV-1 infected cells capable of reseeding the infection, and the mechanisms whereby they are maintained.
Collapse
|
65
|
Lambrechts L, Cole B, Rutsaert S, Trypsteen W, Vandekerckhove L. Emerging PCR-Based Techniques to Study HIV-1 Reservoir Persistence. Viruses 2020; 12:E149. [PMID: 32012811 PMCID: PMC7077278 DOI: 10.3390/v12020149] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2019] [Revised: 01/24/2020] [Accepted: 01/26/2020] [Indexed: 02/04/2023] Open
Abstract
While current antiretroviral therapies are able to halt HIV-1 progression, they are not curative, as an interruption of treatment usually leads to viral rebound. The persistence of this stable HIV-1 latent reservoir forms the major barrier in HIV-1 cure research. The need for a better understanding of the mechanisms behind reservoir persistence resulted in the development of several novel assays allowing to perform an extensive in-depth characterization. The objective of this review is to present an overview of the current state-of-the-art PCR-based technologies to study the replication-competent HIV-1 reservoir. Here, we outline the advantages, limitations, and clinical relevance of different approaches. Future HIV-1 eradication studies would benefit from information-rich, high-throughput assays as they provide a more efficient and standardized way of characterizing the persisting HIV-1 reservoir.
Collapse
Affiliation(s)
- Laurens Lambrechts
- HIV Cure Research Center, Department of Internal Medicine and Pediatrics, Ghent University, 9000 Ghent, Belgium; (L.L.); (B.C.); (S.R.); (W.T.)
- BioBix, Department of Data Analysis and Mathematical Modelling, Faculty of Bioscience Engineering, Ghent University, 9000 Ghent, Belgium
| | - Basiel Cole
- HIV Cure Research Center, Department of Internal Medicine and Pediatrics, Ghent University, 9000 Ghent, Belgium; (L.L.); (B.C.); (S.R.); (W.T.)
| | - Sofie Rutsaert
- HIV Cure Research Center, Department of Internal Medicine and Pediatrics, Ghent University, 9000 Ghent, Belgium; (L.L.); (B.C.); (S.R.); (W.T.)
| | - Wim Trypsteen
- HIV Cure Research Center, Department of Internal Medicine and Pediatrics, Ghent University, 9000 Ghent, Belgium; (L.L.); (B.C.); (S.R.); (W.T.)
| | - Linos Vandekerckhove
- HIV Cure Research Center, Department of Internal Medicine and Pediatrics, Ghent University, 9000 Ghent, Belgium; (L.L.); (B.C.); (S.R.); (W.T.)
| |
Collapse
|
66
|
Liu R, Simonetti FR, Ho YC. The forces driving clonal expansion of the HIV-1 latent reservoir. Virol J 2020; 17:4. [PMID: 31910871 PMCID: PMC6947923 DOI: 10.1186/s12985-019-1276-8] [Citation(s) in RCA: 39] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2019] [Accepted: 12/23/2019] [Indexed: 12/12/2022] Open
Abstract
Despite antiretroviral therapy (ART) which halts HIV-1 replication and reduces plasma viral load to clinically undetectable levels, viral rebound inevitably occurs once ART is interrupted. HIV-1-infected cells can undergo clonal expansion, and these clonally expanded cells increase over time. Over 50% of latent reservoirs are maintained through clonal expansion. The clonally expanding HIV-1-infected cells, both in the blood and in the lymphoid tissues, contribute to viral rebound. The major drivers of clonal expansion of HIV-1-infected cells include antigen-driven proliferation, homeostatic proliferation and HIV-1 integration site-dependent proliferation. Here, we reviewed how viral, immunologic and genomic factors contribute to clonal expansion of HIV-1-infected cells, and how clonal expansion shapes the HIV-1 latent reservoir. Antigen-specific CD4+ T cells specific for different pathogens have different clonal expansion dynamics, depending on antigen exposure, cytokine profiles and exhaustion phenotypes. Homeostatic proliferation replenishes the HIV-1 latent reservoir without inducing viral expression and immune clearance. Integration site-dependent proliferation, a mechanism also deployed by other retroviruses, leads to slow but steady increase of HIV-1-infected cells harboring HIV-1 proviruses integrated in the same orientation at specific sites of certain cancer-related genes. Targeting clonally expanding HIV-1 latent reservoir without disrupting CD4+ T cell function is a top priority for HIV-1 eradication.
Collapse
Affiliation(s)
- Runxia Liu
- Department of Microbial Pathogenesis, Yale University, New Haven, CT, 06519, USA
| | | | - Ya-Chi Ho
- Department of Microbial Pathogenesis, Yale University, New Haven, CT, 06519, USA.
| |
Collapse
|