1
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Zhang Y, Wang J, Fang Y, Liang W, Lei L, Wang J, Gao X, Ma C, Li M, Guo H, Wei L. IFN-α affects Th17/Treg cell balance through c-Maf and associated with the progression of EBV- SLE. Mol Immunol 2024; 171:22-35. [PMID: 38749236 DOI: 10.1016/j.molimm.2024.05.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2024] [Revised: 04/25/2024] [Accepted: 05/06/2024] [Indexed: 06/13/2024]
Abstract
OBJECTIVES Systemic lupus erythematosus (SLE) is a multi-organ autoimmune disease, of which the pathogens is remains obscure. Viral infection, particularly Epstein Barr viru (EBV) infection, has been considered a common pathogenic factor. This study suggests that c-Maf may be an important target in T cell differentiation during SLE progression, providing a potentially new perspective on the role of viral infection in the pathogenesis of autoimmune diseases. METHODS Cytokines of EBV-infected SLE patients were measured by ELISA and assessed in conjunction with their clinical data. IFN-α, c-Maf, and the differentiation of Th17/Treg cells in SLE patients and MRL/LPR mice were analyzed using FCM, WB, RT-PCR, etc. Following the infection of cells and mice with EBV or viral mimic poly (dA:dT), the changes of the aforementioned indicators were investigated. The relationship among IFN-α, STAT3, c-Maf and Th17 cells was determined by si-RNA technique. RESULTS Many SLE patients are found to be complicated by viral infections; Further, studies have demonstrated that viral infection, especially EBV, is involved in SLE development. This study showed that viral infections might promote IFN-α secretion, inhibit c-Maf expression by activating STAT3, increase Th17 cell differentiation, and lead to the immune imbalance of Th17/Treg cells, thus playing a role in the onset and progression of SLE. CONCLUSION This study demonstrates that EBV infections may contribute to SLE development by activating STAT3 through IFN-α, inhibiting c-Maf, and causing Th17/Treg immune imbalance. Our work provided a new insight into the pathogenesis and treatment of SLE.
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Affiliation(s)
- Yue Zhang
- Department of Immunology, Hebei Medical University, Shijiazhuang, Hebei, China; Key Laboratory of Immune mechanism and Intervention on Serious Disease in Hebei Province, Shijiazhuang, Hebei, China; Department of Rheumatology, The Second Hospital of Hebei Medical University, Shijiazhuang, Hebei, China
| | - Jiachao Wang
- Department of Immunology, Hebei Medical University, Shijiazhuang, Hebei, China; Key Laboratory of Immune mechanism and Intervention on Serious Disease in Hebei Province, Shijiazhuang, Hebei, China
| | - Yaqi Fang
- Department of Immunology, Hebei Medical University, Shijiazhuang, Hebei, China; Key Laboratory of Immune mechanism and Intervention on Serious Disease in Hebei Province, Shijiazhuang, Hebei, China
| | - Wenzhang Liang
- Department of Immunology, Hebei Medical University, Shijiazhuang, Hebei, China; Key Laboratory of Immune mechanism and Intervention on Serious Disease in Hebei Province, Shijiazhuang, Hebei, China
| | - Lingyan Lei
- Department of Rheumatology, The Second Hospital of Hebei Medical University, Shijiazhuang, Hebei, China
| | - Junhai Wang
- Department of Immunology, Hebei Medical University, Shijiazhuang, Hebei, China; Key Laboratory of Immune mechanism and Intervention on Serious Disease in Hebei Province, Shijiazhuang, Hebei, China
| | - Xue Gao
- Department of Immunology, Hebei Medical University, Shijiazhuang, Hebei, China; Key Laboratory of Immune mechanism and Intervention on Serious Disease in Hebei Province, Shijiazhuang, Hebei, China
| | - Cuiqing Ma
- Department of Immunology, Hebei Medical University, Shijiazhuang, Hebei, China; Key Laboratory of Immune mechanism and Intervention on Serious Disease in Hebei Province, Shijiazhuang, Hebei, China
| | - Miao Li
- Department of Immunology, Hebei Medical University, Shijiazhuang, Hebei, China; Key Laboratory of Immune mechanism and Intervention on Serious Disease in Hebei Province, Shijiazhuang, Hebei, China
| | - Huifang Guo
- Department of Rheumatology, The Second Hospital of Hebei Medical University, Shijiazhuang, Hebei, China.
| | - Lin Wei
- Department of Immunology, Hebei Medical University, Shijiazhuang, Hebei, China; Key Laboratory of Immune mechanism and Intervention on Serious Disease in Hebei Province, Shijiazhuang, Hebei, China.
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2
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Ma T, Luo X, George AF, Mukherjee G, Sen N, Spitzer TL, Giudice LC, Greene WC, Roan NR. HIV efficiently infects T cells from the endometrium and remodels them to promote systemic viral spread. eLife 2020; 9:55487. [PMID: 32452381 PMCID: PMC7250576 DOI: 10.7554/elife.55487] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2020] [Accepted: 04/17/2020] [Indexed: 12/16/2022] Open
Abstract
The female reproductive tract (FRT) is the most common site of infection during HIV transmission to women, but viral remodeling complicates characterization of cells targeted for infection. Here, we report extensive phenotypic analyses of HIV-infected endometrial cells by CyTOF, and use a 'nearest neighbor' bioinformatics approach to trace cells to their original pre-infection phenotypes. Like in blood, HIV preferentially targets memory CD4+ T cells in the endometrium, but these cells exhibit unique phenotypes and sustain much higher levels of infection. Genital cell remodeling by HIV includes downregulating TCR complex components and modulating chemokine receptor expression to promote dissemination of infected cells to lymphoid follicles. HIV also upregulates the anti-apoptotic protein BIRC5, which when blocked promotes death of infected endometrial cells. These results suggest that HIV remodels genital T cells to prolong viability and promote viral dissemination and that interfering with these processes might reduce the likelihood of systemic viral spread.
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Affiliation(s)
- Tongcui Ma
- Gladstone Institute of Virology and Immunology, San Francisco, United States.,Department of Urology, University of California, San Francisco, San Francisco, United States
| | - Xiaoyu Luo
- Gladstone Institute of Virology and Immunology, San Francisco, United States
| | - Ashley F George
- Gladstone Institute of Virology and Immunology, San Francisco, United States.,Department of Urology, University of California, San Francisco, San Francisco, United States
| | - Gourab Mukherjee
- Department of Data Sciences and Operations, University of Southern California, Los Angeles, United States
| | - Nandini Sen
- Departments of Pediatrics and Microbiology and Immunology, Stanford School of Medicine, Stanford, United States
| | - Trimble L Spitzer
- Lt Col, United States AF; Women's Health Clinic, Naval Medical Center, Portsmouth, United States
| | - Linda C Giudice
- Center for Reproductive Sciences, Department of Obstetrics, Gynecology and Reproductive Sciences, University of California, San Francisco, San Francisco, United States
| | - Warner C Greene
- Gladstone Institute of Virology and Immunology, San Francisco, United States.,Department of Medicine, University of California, San Francisco, San Francisco, United States
| | - Nadia R Roan
- Gladstone Institute of Virology and Immunology, San Francisco, United States.,Department of Urology, University of California, San Francisco, San Francisco, United States
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3
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Putatunda R, Ho WZ, Hu W. HIV-1 and Compromised Adult Neurogenesis: Emerging Evidence for a New Paradigm of HAND Persistence. AIDS Rev 2019; 21:11-22. [PMID: 30899112 DOI: 10.24875/aidsrev.19000003] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The face of the HIV-1/AIDS pandemic has changed significantly thanks to the development of antiretroviral therapy (ART) regimens. Unfortunately, several HIV-associated comorbidities continuously occur in the clinical population, most notably HIV-associated neurocognitive disorders (HAND). While many molecular and cellular mechanisms have been characterized by describing HAND pathology (specifically neuroinflammatory insults and oxidative stress) in the ART era, compromised adult neurogenesis is emerging as a potential new mechanism. Neurogenesis is a dynamic process that generates new neurons and glial cells from neural stem cells (NSCs) and neural progenitor cells (NPCs) in specific areas of the brain. There are increasing observations that HIV-1 can productively and non-productively infect NSCs and NPCs. HIV-1 proteins and/or secondary immune/inflammatory responses impair the initial differentiation process of NSCs to NPCs, restrict neuronal lineage differentiation, and aberrantly promote astrocytic lineage differentiation. Recent studies with HIV-1 transgenic animal models demonstrate varying degrees of adult neurogenic deficits, which correlate with milder to moderate forms of neurocognitive impairments. The neurogenic dysfunction underlying HAND highlights the importance of developing potential therapeutics to restore adult neurogenic homeostasis in HIV-1 patients.
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Affiliation(s)
- Raj Putatunda
- Department of Pathology and Laboratory Medicine, Philadelphia, Pennsylvania, USA
- Center for Metabolic Disease Research, Temple University Lewis Katz School of Medicine, Philadelphia, Pennsylvania, USA
| | - Wen-Zhe Ho
- Department of Pathology and Laboratory Medicine, Philadelphia, Pennsylvania, USA
| | - Wenhui Hu
- Department of Pathology and Laboratory Medicine, Philadelphia, Pennsylvania, USA
- Center for Metabolic Disease Research, Temple University Lewis Katz School of Medicine, Philadelphia, Pennsylvania, USA
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4
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Prasad A, Kulkarni R, Shrivastava A, Jiang S, Lawson K, Groopman JE. Methamphetamine functions as a novel CD4 + T-cell activator via the sigma-1 receptor to enhance HIV-1 infection. Sci Rep 2019; 9:958. [PMID: 30700725 PMCID: PMC6353873 DOI: 10.1038/s41598-018-35757-x] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2018] [Accepted: 11/05/2018] [Indexed: 11/09/2022] Open
Abstract
Methamphetamine (Meth) exacerbates HIV-1 pathobiology by increasing virus transmission and replication and accelerating clinical progression to AIDS. Meth has been shown to alter the expression of HIV-1 co-receptors and impair intrinsic resistance mechanisms of immune cells. However, the exact molecular mechanisms involved in augmenting HIV-1 replication in T-cells are still not yet clear. Here, we demonstrate that pretreatment with Meth of CD4+ T-cells enhanced HIV-1 replication. We observed upregulation of CD4+ T-cell activation markers and enhanced expression of miR-34c-5p and miR-155 in these cells. Further, we noted activation of the sigma-1 receptor and enhanced intracellular Ca2+ concentration and cAMP release in CD4+ T-cells upon Meth treatment, which resulted in increased phosphorylation and nuclear translocation of transcription factors NFκB, CREB, and NFAT1. Increased gene expression of IL-4 and IL-10 was also observed in Meth treated CD4+ T-cells. Moreover, proteasomal degradation of Ago1 occurred upon Meth treatment, further substantiating the drug as an activator of T-cells. Taken together, these findings show a previously unreported mechanism whereby Meth functions as a novel T-cell activator via the sigma-1 signaling pathway, enhancing replication of HIV-1 with expression of miR-34c-5p, and transcriptional activation of NFκB, CREB and NFAT1.
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Affiliation(s)
- Anil Prasad
- Division of Experimental Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, 02215, USA
| | - Rutuja Kulkarni
- Division of Experimental Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, 02215, USA
| | - Ashutosh Shrivastava
- Division of Experimental Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, 02215, USA
- Molecular Biology Unit, Center for Advance Research, King George's Medical University, Lucknow, India
| | - Shuxian Jiang
- Division of Experimental Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, 02215, USA
| | - Kaycie Lawson
- Division of Experimental Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, 02215, USA
| | - Jerome E Groopman
- Division of Experimental Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, 02215, USA.
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5
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Agosto LM, Henderson AJ. CD4 + T Cell Subsets and Pathways to HIV Latency. AIDS Res Hum Retroviruses 2018; 34:780-789. [PMID: 29869531 DOI: 10.1089/aid.2018.0105] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Latent infection of CD4+ T cells is the main barrier to eradicating HIV-1 infection from infected patients. The cellular and molecular mechanisms involved in the establishment and maintenance of latent infection are directly linked to the transcriptional program of the different CD4+ T cell subsets targeted by the virus. In this review, we provide an overview of how T cell activation, T cell differentiation into functional subsets, and the mode of initial viral infection influence HIV proviral transcription and entry into latency.
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Affiliation(s)
- Luis M. Agosto
- Section of Infectious Diseases, Department of Medicine, Boston University Medical Center, Boston, Massachusetts
| | - Andrew J. Henderson
- Section of Infectious Diseases, Department of Medicine, Boston University Medical Center, Boston, Massachusetts
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6
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Schulert GS, Zhang M, Husami A, Fall N, Brunner H, Zhang K, Cron RQ, Grom AA. Brief Report: Novel UNC13D Intronic Variant Disrupting an NF-κB Enhancer in a Patient With Recurrent Macrophage Activation Syndrome and Systemic Juvenile Idiopathic Arthritis. Arthritis Rheumatol 2018; 70:963-970. [PMID: 29409136 DOI: 10.1002/art.40438] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2017] [Accepted: 01/30/2018] [Indexed: 01/24/2023]
Abstract
OBJECTIVE Macrophage activation syndrome (MAS) is a life-threatening complication of systemic juvenile idiopathic arthritis (JIA) and has pathologic similarity to hemophagocytic lymphohistiocytosis (HLH). Intronic variants in UNC13D are found in patients with familial HLH type 3 (FHLH3), but the role of noncoding variants in MAS is unknown. The objective of this study was to identify deep intronic UNC13D variants in patients with MAS. METHODS A custom enrichment library was constructed to sequence a genomic region of ~1 Mb flanking UNC13D in 24 patients with systemic JIA, recurrent MAS, and negative results of prior genetic (exon/coding) testing. The functional consequences of intronic variants were assessed using quantitative polymerase chain reaction in patient-derived peripheral blood mononuclear cells (PBMCs), electromobility shift assay, in vitro transcriptional enhancer assays, and natural killer (NK) cell degranulation assays. RESULTS We evaluated a patient with systemic JIA and recurrent MAS in whom a novel functional intronic variant in UNC13D, c.117+143A>G, was observed. This variant occurred in a proposed regulatory region that drives lymphocyte-specific UNC13D expression and is associated with reduced transcript levels in patient PBMCs. This variant also disrupted NF-κB binding to a functional transcriptional enhancer, leading to reduced enhancer activity in vitro. Partial knockdown of UNC13D expression also led to impaired NK cell degranulation. An additional patient was identified with a previously described UNC13D intronic variant, for a total noncoding variant hit rate of 8.3% (2 of 24). CONCLUSION These findings highlight the notion that intronic variants in key regulatory regions may be associated with MAS in patients with systemic JIA and support deep sequencing approaches when causative coding variants are not identified.
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Affiliation(s)
- Grant S Schulert
- Cincinnati Children's Hospital Medical Center and University of Cincinnati College of Medicine, Cincinnati, Ohio
| | - Mingce Zhang
- Children's Hospital of Alabama, University of Alabama at Birmingham
| | - Ammar Husami
- Cincinnati Children's Hospital Medical Center and University of Cincinnati College of Medicine, Cincinnati, Ohio
| | - Ndate Fall
- Cincinnati Children's Hospital Medical Center and University of Cincinnati College of Medicine, Cincinnati, Ohio
| | - Hermine Brunner
- Cincinnati Children's Hospital Medical Center and University of Cincinnati College of Medicine, Cincinnati, Ohio
| | - Kejian Zhang
- Cincinnati Children's Hospital Medical Center and University of Cincinnati College of Medicine, Cincinnati, Ohio
| | - Randy Q Cron
- Children's Hospital of Alabama, University of Alabama at Birmingham
| | - Alexei A Grom
- Cincinnati Children's Hospital Medical Center and University of Cincinnati College of Medicine, Cincinnati, Ohio
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7
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Zhang M, Robinson TO, Duverger A, Kutsch O, Heath SL, Cron RQ. Regulatory CD4 T cells inhibit HIV-1 expression of other CD4 T cell subsets via interactions with cell surface regulatory proteins. Virology 2018; 516:21-29. [PMID: 29324358 DOI: 10.1016/j.virol.2017.12.036] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2017] [Revised: 12/28/2017] [Accepted: 12/29/2017] [Indexed: 01/16/2023]
Abstract
During chronic HIV-1 infection, regulatory CD4 T cells (Tregs) frequently represent the largest subpopulation of CD4 T cell subsets, implying relative resistant to HIV-1. When HIV-1 infection of CD4 T cells was explored in vitro and ex vivo from patient samples, Tregs possessed lower levels of HIV-1 DNA and RNA in comparison with conventional effector and memory CD4 T cells. Moreover, Tregs suppressed HIV-1 expression in other CD4 T cells in an in vitro co-culture system. This suppression was mediated in part via multiple inhibitory surface proteins expressed on Tregs. Antibody blockade of CTLA-4, PD-1, and GARP on Tregs resulted in increased HIV-1 DNA integration and mRNA expression in neighboring CD4 T cells. Moreover, antibody blockade of Tregs inhibitory proteins resulted in increased HIV-1 LTR transcription in co-cultured CD4 T cells. Thus, Tregs inhibit HIV-1 infection of other CD4 T cell subsets via interactions with inhibitory cell surface proteins.
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Affiliation(s)
- Mingce Zhang
- Division of Rheumatology, Department of Pediatrics, University of Alabama at Birmingham, Birmingham, AL, USA.
| | - Tanya O Robinson
- Division of Rheumatology, Department of Pediatrics, University of Alabama at Birmingham, Birmingham, AL, USA.
| | - Alexandra Duverger
- Division of Infectious Diseases, Department of Medicine, University of Alabama at Birmingham, Birmingham, AL, USA.
| | - Olaf Kutsch
- Division of Infectious Diseases, Department of Medicine, University of Alabama at Birmingham, Birmingham, AL, USA.
| | - Sonya L Heath
- Division of Infectious Diseases, Department of Medicine, University of Alabama at Birmingham, Birmingham, AL, USA.
| | - Randy Q Cron
- Division of Rheumatology, Department of Pediatrics, University of Alabama at Birmingham, Birmingham, AL, USA.
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8
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Lee GQ, Orlova-Fink N, Einkauf K, Chowdhury FZ, Sun X, Harrington S, Kuo HH, Hua S, Chen HR, Ouyang Z, Reddy K, Dong K, Ndung'u T, Walker BD, Rosenberg ES, Yu XG, Lichterfeld M. Clonal expansion of genome-intact HIV-1 in functionally polarized Th1 CD4+ T cells. J Clin Invest 2017. [PMID: 28628034 DOI: 10.1172/jci93289] [Citation(s) in RCA: 224] [Impact Index Per Article: 32.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
HIV-1 causes a chronic, incurable disease due to its persistence in CD4+ T cells that contain replication-competent provirus, but exhibit little or no active viral gene expression and effectively resist combination antiretroviral therapy (cART). These latently infected T cells represent an extremely small proportion of all circulating CD4+ T cells but possess a remarkable long-term stability and typically persist throughout life, for reasons that are not fully understood. Here we performed massive single-genome, near-full-length next-generation sequencing of HIV-1 DNA derived from unfractionated peripheral blood mononuclear cells, ex vivo-isolated CD4+ T cells, and subsets of functionally polarized memory CD4+ T cells. This approach identified multiple sets of independent, near-full-length proviral sequences from cART-treated individuals that were completely identical, consistent with clonal expansion of CD4+ T cells harboring intact HIV-1. Intact, near-full-genome HIV-1 DNA sequences that were derived from such clonally expanded CD4+ T cells constituted 62% of all analyzed genome-intact sequences in memory CD4 T cells, were preferentially observed in Th1-polarized cells, were longitudinally detected over a duration of up to 5 years, and were fully replication- and infection-competent. Together, these data suggest that clonal proliferation of Th1-polarized CD4+ T cells encoding for intact HIV-1 represents a driving force for stabilizing the pool of latently infected CD4+ T cells.
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Affiliation(s)
- Guinevere Q Lee
- Infectious Disease Division, Brigham and Women's Hospital, Boston, Massachusetts, USA.,Ragon Institute of MGH, MIT, and Harvard, Cambridge, Massachusetts, USA
| | - Nina Orlova-Fink
- Ragon Institute of MGH, MIT, and Harvard, Cambridge, Massachusetts, USA
| | - Kevin Einkauf
- Ragon Institute of MGH, MIT, and Harvard, Cambridge, Massachusetts, USA
| | | | - Xiaoming Sun
- Ragon Institute of MGH, MIT, and Harvard, Cambridge, Massachusetts, USA
| | - Sean Harrington
- Ragon Institute of MGH, MIT, and Harvard, Cambridge, Massachusetts, USA
| | - Hsiao-Hsuan Kuo
- Infectious Disease Division, Brigham and Women's Hospital, Boston, Massachusetts, USA.,Ragon Institute of MGH, MIT, and Harvard, Cambridge, Massachusetts, USA
| | - Stephane Hua
- Ragon Institute of MGH, MIT, and Harvard, Cambridge, Massachusetts, USA
| | - Hsiao-Rong Chen
- Ragon Institute of MGH, MIT, and Harvard, Cambridge, Massachusetts, USA
| | - Zhengyu Ouyang
- Ragon Institute of MGH, MIT, and Harvard, Cambridge, Massachusetts, USA
| | - Kavidha Reddy
- HIV Pathogenesis Programme, Doris Duke Medical Research Institute, and
| | - Krista Dong
- HIV Pathogenesis Programme, Doris Duke Medical Research Institute, and
| | - Thumbi Ndung'u
- Ragon Institute of MGH, MIT, and Harvard, Cambridge, Massachusetts, USA.,HIV Pathogenesis Programme, Doris Duke Medical Research Institute, and.,KwaZulu-Natal Research Institute for Tuberculosis and HIV (K-RITH), Nelson R. Mandela School of Medicine, University of KwaZulu-Natal, Durban, South Africa.,Max Planck Institute for Infection Biology, Berlin, Germany
| | - Bruce D Walker
- Ragon Institute of MGH, MIT, and Harvard, Cambridge, Massachusetts, USA.,Howard Hughes Medical Institute, Chevy Chase, Maryland, USA
| | - Eric S Rosenberg
- Infectious Disease Division, Massachusetts General Hospital, Boston, Massachusetts, USA
| | - Xu G Yu
- Infectious Disease Division, Brigham and Women's Hospital, Boston, Massachusetts, USA.,Ragon Institute of MGH, MIT, and Harvard, Cambridge, Massachusetts, USA
| | - Mathias Lichterfeld
- Infectious Disease Division, Brigham and Women's Hospital, Boston, Massachusetts, USA.,Ragon Institute of MGH, MIT, and Harvard, Cambridge, Massachusetts, USA
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9
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Functional Incompatibility between the Generic NF-κB Motif and a Subtype-Specific Sp1III Element Drives the Formation of the HIV-1 Subtype C Viral Promoter. J Virol 2016; 90:7046-7065. [PMID: 27194770 DOI: 10.1128/jvi.00308-16] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2016] [Accepted: 05/12/2016] [Indexed: 12/22/2022] Open
Abstract
UNLABELLED Of the various genetic subtypes of human immunodeficiency virus types 1 and 2 (HIV-1 and HIV-2) and simian immunodeficiency virus (SIV), only in subtype C of HIV-1 is a genetically variant NF-κB binding site found at the core of the viral promoter in association with a subtype-specific Sp1III motif. How the subtype-associated variations in the core transcription factor binding sites (TFBS) influence gene expression from the viral promoter has not been examined previously. Using panels of infectious viral molecular clones, we demonstrate that subtype-specific NF-κB and Sp1III motifs have evolved for optimal gene expression, and neither of the motifs can be replaced by a corresponding TFBS variant. The variant NF-κB motif binds NF-κB with an affinity 2-fold higher than that of the generic NF-κB site. Importantly, in the context of an infectious virus, the subtype-specific Sp1III motif demonstrates a profound loss of function in association with the generic NF-κB motif. An additional substitution of the Sp1III motif fully restores viral replication, suggesting that the subtype C-specific Sp1III has evolved to function with the variant, but not generic, NF-κB motif. A change of only two base pairs in the central NF-κB motif completely suppresses viral transcription from the provirus and converts the promoter into heterochromatin refractory to tumor necrosis factor alpha (TNF-α) induction. The present work represents the first demonstration of functional incompatibility between an otherwise functional NF-κB motif and a unique Sp1 site in the context of an HIV-1 promoter. Our work provides important leads as to the evolution of the HIV-1 subtype C viral promoter with relevance for gene expression regulation and viral latency. IMPORTANCE Subtype-specific genetic variations provide a powerful tool to examine how these variations offer a replication advantage to specific viral subtypes, if any. Only in subtype C of HIV-1 are two genetically distinct transcription factor binding sites positioned at the most critical location of the viral promoter. Since a single promoter regulates viral gene expression, the promoter variations can play a critical role in determining the replication fitness of the viral strains. Our work for the first time provides a scientific explanation for the presence of a unique NF-κB binding motif in subtype C, a major HIV-1 genetic family responsible for half of the global HIV-1 infections. The results offer compelling evidence that the subtype C viral promoter not only is stronger but also is endowed with a qualitative gain-of-function advantage. The genetically variant NF-κB and the Sp1III motifs may be respond differently to specific cell signal pathways, and these mechanisms must be examined.
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10
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Hodgson A, Wan F. Interference with nuclear factor kappaB signaling pathway by pathogen-encoded proteases: global and selective inhibition. Mol Microbiol 2016; 99:439-52. [PMID: 26449378 PMCID: PMC5003429 DOI: 10.1111/mmi.13245] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/08/2015] [Indexed: 01/26/2023]
Abstract
Pathogens have evolved a myriad of ways to abrogate and manipulate the host response to infections. Of the various mechanisms involved, pathogen-encoded and sometimes host-encoded proteases are an important category of virulence factors that cause robust changes on the host response by targeting key proteins along signaling cascades. The nuclear factor kappaB (NF-κB) signaling pathway is a crucial regulatory mechanism for the cell, controlling the expression of survival, immune and proliferation genes. Proteases from pathogens of almost all types have been demonstrated to target and cleave members of the NF-κB signaling pathway at nearly every level. This review provides discussion of proteases targeting the most abundant NF-κB subunit, p65, and the impact of protease-mediated p65 cleavage on the immune responses and survival of the infected host cell. After examining various examples of protease interference, it becomes evident that the cleavage fragments produced by pathogen-driven proteolytic processing should be further characterized to determine whether they have novel and unique functions within the cell. The selective targeting of p65 and its effect on gene transcription reveals unique mechanisms by which pathogens acutely alter their microenvironment, and further research may open new opportunities for novel therapeutics to combat pathogens.
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Affiliation(s)
- Andrea Hodgson
- Department of Biochemistry and Molecular Biology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD 21025, USA
- W. Harry Feinstone Department of Molecular Microbiology and Immunology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD 21025, USA
| | - Fengyi Wan
- Department of Biochemistry and Molecular Biology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD 21025, USA
- Department of Oncology, Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University, Baltimore, MD 21287, USA
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11
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Chan CN, Trinité B, Lee CS, Mahajan S, Anand A, Wodarz D, Sabbaj S, Bansal A, Goepfert PA, Levy DN. HIV-1 latency and virus production from unintegrated genomes following direct infection of resting CD4 T cells. Retrovirology 2016; 13:1. [PMID: 26728316 PMCID: PMC4700562 DOI: 10.1186/s12977-015-0234-9] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2015] [Accepted: 12/21/2015] [Indexed: 12/31/2022] Open
Abstract
Background HIV-1 integration is prone to a high rate of failure, resulting in the accumulation of unintegrated viral genomes (uDNA) in vivo and in vitro. uDNA can be transcriptionally active, and circularized uDNA genomes are biochemically stable in non-proliferating cells. Resting, non-proliferating CD4 T cells are prime targets of HIV-1 infection and latently infected resting CD4 T cells are the major barrier to HIV cure. Our prior studies demonstrated that uDNA generates infectious virions when T cell activation follows rather than precedes infection. Results Here, we characterize in primary resting CD4 T cells the dynamics of integrated and unintegrated virus expression, genome persistence and sensitivity to latency reversing agents. Unintegrated HIV-1 was abundant in directly infected resting CD4 T cells. Maximal gene expression from uDNA was delayed compared with integrated HIV-1 and was less toxic, resulting in uDNA enrichment over time relative to integrated proviruses. Inhibiting integration with raltegravir shunted the generation of durable latency from integrated to unintegrated genomes. Latent uDNA was activated to de novo virus production by latency reversing agents that also activated latent integrated proviruses, including PKC activators, histone deacetylase inhibitors and P-TEFb agonists. However, uDNA responses displayed a wider dynamic range, indicating differential regulation of expression relative to integrated proviruses. Similar to what has recently been demonstrated for latent integrated proviruses, one or two applications of latency reversing agents failed to activate all latent unintegrated genomes. Unlike integrated proviruses, uDNA gene expression did not down modulate expression of HLA Class I on resting CD4 T cells. uDNA did, however, efficiently prime infected cells for killing by HIV-1-specific cytotoxic T cells. Conclusions These studies demonstrate that contributions by unintegrated genomes to HIV-1 gene expression, virus production, latency and immune responses are inherent properties of the direct infection of resting CD4 T cells. Experimental models of HIV-1 latency employing directly infected resting CD4 T cells should calibrate the contribution of unintegrated HIV-1. Electronic supplementary material The online version of this article (doi:10.1186/s12977-015-0234-9) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Chi N Chan
- Department of Basic Science, New York University College of Dentistry, New York, NY, 10010, USA.
| | - Benjamin Trinité
- Department of Basic Science, New York University College of Dentistry, New York, NY, 10010, USA.
| | - Caroline S Lee
- Department of Basic Science, New York University College of Dentistry, New York, NY, 10010, USA.
| | - Saurabh Mahajan
- Department of Basic Science, New York University College of Dentistry, New York, NY, 10010, USA.
| | - Akanksha Anand
- Department of Basic Science, New York University College of Dentistry, New York, NY, 10010, USA.
| | - Dominik Wodarz
- Department of Ecology and Evolutionary Biology, University of California, Irvine, School of Biological, Sciences, Irvine, CA, 92697, USA.
| | - Steffanie Sabbaj
- Department of Medicine, University of Alabama at Birmingham, Birmingham, AL, 35294, USA.
| | - Anju Bansal
- Department of Medicine, University of Alabama at Birmingham, Birmingham, AL, 35294, USA.
| | - Paul A Goepfert
- Department of Medicine, University of Alabama at Birmingham, Birmingham, AL, 35294, USA.
| | - David N Levy
- Department of Basic Science, New York University College of Dentistry, New York, NY, 10010, USA.
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12
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Kaczmarek Michaels K, Natarajan M, Euler Z, Alter G, Viglianti G, Henderson AJ. Blimp-1, an intrinsic factor that represses HIV-1 proviral transcription in memory CD4+ T cells. THE JOURNAL OF IMMUNOLOGY 2015; 194:3267-74. [PMID: 25710909 DOI: 10.4049/jimmunol.1402581] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
CD4(+) T cell subsets differentially support HIV-1 replication. For example, quiescent CD4(+) memory T cells are susceptible to HIV-1 infection but do not support robust HIV-1 transcription and have been implicated as the primary reservoir of latent HIV-1. T cell transcription factors that regulate maturation potentially limit HIV-1 transcription and mediate the establishment and maintenance of HIV-1 latency. We report that B lymphocyte-induced maturation protein-1 (Blimp-1), a critical regulator of B and T cell differentiation, is highly expressed in memory CD4(+) T cells compared with naive CD4(+) T cells and represses basal and Tat-mediated HIV-1 transcription. Blimp-1 binds an IFN-stimulated response element within HIV-1 provirus, and it is displaced following T cell activation. Reduction of Blimp-1 in infected primary T cells including CD4(+) memory T cells increases RNA polymerase II processivity, histone acetylation, and baseline HIV-1 transcription. Therefore, the transcriptional repressor, Blimp-1, is an intrinsic factor that predisposes CD4(+) memory T cells to latent HIV-1 infection.
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Affiliation(s)
- Katarzyna Kaczmarek Michaels
- Section of Infectious Diseases, Department of Medicine, Boston University School of Medicine, Boston, MA 02118; Graduate Program in Molecular and Translational Medicine, Boston University School of Medicine, Boston, MA 02118
| | | | - Zelda Euler
- Ragon Institute of MGH, MIT and Harvard University, Boston, MA 02139; and
| | - Galit Alter
- Ragon Institute of MGH, MIT and Harvard University, Boston, MA 02139; and
| | - Gregory Viglianti
- Department of Microbiology, Boston University School of Medicine, Boston, MA 02118
| | - Andrew J Henderson
- Section of Infectious Diseases, Department of Medicine, Boston University School of Medicine, Boston, MA 02118; Graduate Program in Molecular and Translational Medicine, Boston University School of Medicine, Boston, MA 02118; Department of Microbiology, Boston University School of Medicine, Boston, MA 02118
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13
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Zhang M, Ma Z, Selliah N, Weiss G, Genin A, Finkel TH, Cron RQ. The impact of Nucleofection® on the activation state of primary human CD4 T cells. J Immunol Methods 2014; 408:123-31. [PMID: 24910411 DOI: 10.1016/j.jim.2014.05.014] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2014] [Revised: 05/29/2014] [Accepted: 05/29/2014] [Indexed: 12/13/2022]
Abstract
Gene transfer into primary human CD4 T lymphocytes is a critical tool in studying the mechanism of T cell-dependent immune responses and human immunodeficiency virus-1 (HIV-1) infection. Nucleofection® is an electroporation technique that allows efficient gene transfer into primary human CD4 T cells that are notoriously resistant to traditional electroporation. Despite its popularity in immunological research, careful characterization of its impact on the physiology of CD4 T cells has not been documented. Herein, using freshly-isolated primary human CD4 T cells, we examine the effects of Nucleofection® on CD4 T cell morphology, intracellular calcium levels, cell surface activation markers, and transcriptional activity. We find that immediately after Nucleofection®, CD4 T cells undergo dramatic morphological changes characterized by wrinkled and dilated plasma membranes before recovering 1h later. The intracellular calcium level also increases after Nucleofection®, peaking after 1h before recovering 8h post transfection. Moreover, Nucleofection® leads to increased expression of T cell activation markers, CD154 and CD69, for more than 24h, and enhances the activation effects of phytohemagglutinin (PHA) stimulation. In addition, transcriptional activity is increased in the first 24h after Nucleofection®, even in the absence of exogenous stimuli. Therefore, Nucleofection® significantly alters the activation state of primary human CD4 T cells. The effect of transferred gene products on CD4 T cell function by Nucleofection® should be assessed after sufficient resting time post transfection or analyzed in light of the activation caveats mentioned above.
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Affiliation(s)
- Mingce Zhang
- Division of Pediatric Rheumatology, University of Alabama at Birmingham, 1825 University Blvd,. Shelby Building, Rm. 371, Birmingham, AL 35233, United States.
| | - Zhengyu Ma
- Nemours/A. I. duPont Hospital for Children, 1600 Rockland Road, Wilmington, DE 19803, United States.
| | - Nithianandan Selliah
- Celgene Cellular Therapeutics, 7 Powder Horn Dr., Warren, NJ 07059, United States.
| | - Greta Weiss
- Burnet Institute, 85 Commercial Road, Melbourne, Victoria 3004, Australia.
| | - Anna Genin
- Division of Pediatric Rheumatology, University of Alabama at Birmingham, 1825 University Blvd,. Shelby Building, Rm. 371, Birmingham, AL 35233, United States.
| | - Terri H Finkel
- Nemours Children's Hospital, 13535 Nemours Parkway, Orlando, FL 32827, United States.
| | - Randy Q Cron
- Division of Pediatric Rheumatology, University of Alabama at Birmingham, 1825 University Blvd,. Shelby Building, Rm. 371, Birmingham, AL 35233, United States.
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14
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Sriram U, Xu J, Chain RW, Varghese L, Chakhtoura M, Bennett HL, Zoltick PW, Gallucci S. IL-4 suppresses the responses to TLR7 and TLR9 stimulation and increases the permissiveness to retroviral infection of murine conventional dendritic cells. PLoS One 2014; 9:e87668. [PMID: 24489947 PMCID: PMC3906189 DOI: 10.1371/journal.pone.0087668] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2013] [Accepted: 12/28/2013] [Indexed: 12/11/2022] Open
Abstract
Th2-inducing pathological conditions such as parasitic diseases increase susceptibility to viral infections through yet unclear mechanisms. We have previously reported that IL-4, a pivotal Th2 cytokine, suppresses the response of murine bone-marrow-derived conventional dendritic cells (cDCs) and splenic DCs to Type I interferons (IFNs). Here, we analyzed cDC responses to TLR7 and TLR9 ligands, R848 and CpGs, respectively. We found that IL-4 suppressed the gene expression of IFNβ and IFN-responsive genes (IRGs) upon TLR7 and TLR9 stimulation. IL-4 also inhibited IFN-dependent MHC Class I expression and amplification of IFN signaling pathways triggered upon TLR stimulation, as indicated by the suppression of IRF7 and STAT2. Moreover, IL-4 suppressed TLR7- and TLR9-induced cDC production of pro-inflammatory cytokines such as TNFα, IL-12p70 and IL-6 by inhibiting IFN-dependent and NFκB-dependent responses. IL-4 similarly suppressed TLR responses in splenic DCs. IL-4 inhibition of IRGs and pro-inflammatory cytokine production upon TLR7 and TLR9 stimulation was STAT6-dependent, since DCs from STAT6-KO mice were resistant to the IL-4 suppression. Analysis of SOCS molecules (SOCS1, −2 and −3) showed that IL-4 induces SOCS1 and SOCS2 in a STAT6 dependent manner and suggest that IL-4 suppression could be mediated by SOCS molecules, in particular SOCS2. IL-4 also decreased the IFN response and increased permissiveness to viral infection of cDCs exposed to a HIV-based lentivirus. Our results indicate that IL-4 modulates and counteracts pro-inflammatory stimulation induced by TLR7 and TLR9 and it may negatively affect responses against viruses and intracellular parasites.
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Affiliation(s)
- Uma Sriram
- Laboratory of Dendritic Cell Biology, Department of Microbiology and Immunology, Temple University, School of Medicine, Philadelphia, Pennsylvania, United States of America
- * E-mail: (US); (SG)
| | - Jun Xu
- Laboratory of Dendritic Cell Biology, Department of Microbiology and Immunology, Temple University, School of Medicine, Philadelphia, Pennsylvania, United States of America
| | - Robert W. Chain
- Laboratory of Dendritic Cell Biology, Department of Microbiology and Immunology, Temple University, School of Medicine, Philadelphia, Pennsylvania, United States of America
| | - Linda Varghese
- Laboratory of Dendritic Cell Biology, Department of Microbiology and Immunology, Temple University, School of Medicine, Philadelphia, Pennsylvania, United States of America
| | - Marita Chakhtoura
- Laboratory of Dendritic Cell Biology, Department of Microbiology and Immunology, Temple University, School of Medicine, Philadelphia, Pennsylvania, United States of America
| | - Heather L. Bennett
- Joseph Stokes, Jr. Research Institute, Division of Rheumatology, Department of Pediatrics, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, United States of America
| | - Philip W. Zoltick
- Department of Surgery, The Children's Center for Fetal Research, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, United States of America
| | - Stefania Gallucci
- Laboratory of Dendritic Cell Biology, Department of Microbiology and Immunology, Temple University, School of Medicine, Philadelphia, Pennsylvania, United States of America
- * E-mail: (US); (SG)
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15
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Calcium/calcineurin synergizes with prostratin to promote NF-κB dependent activation of latent HIV. PLoS One 2013; 8:e77749. [PMID: 24204950 PMCID: PMC3813743 DOI: 10.1371/journal.pone.0077749] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2013] [Accepted: 09/06/2013] [Indexed: 01/19/2023] Open
Abstract
Attempts to eradicate HIV have been thwarted by the persistence of a small pool of quiescent memory CD4 T cells that harbor a transcriptionally silent, integrated form of the virus that can produce infectious virions following an anamnestic immune response. Transcription factors downstream of T-cell receptor activation, such as NF-κB/Rel and nuclear factor of activated T cells (NFAT) transcription members, are considered important regulators of HIV transcription during acute HIV infection. We now report studies exploring their precise role as antagonists of HIV latency using cell and primary CD4 T cell models of HIV-1 latency. Surprisingly, RNA interference studies performed in J-Lat CD4 T cells suggested that none of the NFATs, including NFATc1, NFATc2, NFATc3, and NFAT5, played a key role in the reactivation of latent HIV. However, cyclosporin A markedly inhibited the reactivation response. These results were reconciled when calcium signaling through calcineurin was shown to potentiate prostratin induced activation of NF-κB that in turn stimulated the latent HIV long terminal repeat (LTR). Similar effects of calcineurin were confirmed in a primary CD4 T cell model of HIV latency. These findings highlight an important role for calcineurin in NF-κB-dependent induction of latent HIV transcription. Innovative approaches exploiting the synergistic actions of calcineurin and prostratin in the absence of generalized T-cell activation merit exploration as a means to attack the latent viral reservoir.
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16
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Kinase control of latent HIV-1 infection: PIM-1 kinase as a major contributor to HIV-1 reactivation. J Virol 2013; 88:364-76. [PMID: 24155393 DOI: 10.1128/jvi.02682-13] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Despite the clinical relevance of latent HIV-1 infection as a block to HIV-1 eradication, the molecular biology of HIV-1 latency remains incompletely understood. We recently demonstrated the presence of a gatekeeper kinase function that controls latent HIV-1 infection. Using kinase array analysis, we here expand on this finding and demonstrate that the kinase activity profile of latently HIV-1-infected T cells is altered relative to that of uninfected T cells. A ranking of altered kinases generated from these kinome profile data predicted PIM-1 kinase as a key switch involved in HIV-1 latency control. Using genetic and pharmacologic perturbation strategies, we demonstrate that PIM-1 activity is indeed required for HIV-1 reactivation in T cell lines and primary CD4 T cells. The presented results thus confirm that kinases are key contributors to HIV-1 latency control. In addition, through mutational studies we link the inhibitory effect of PIM-1 inhibitor IV (PIMi IV) on HIV-1 reactivation to an AP-1 motif in the CD28-responsive element of the HIV-1 long terminal repeat (LTR). The results expand our conceptual understanding of the dynamic interactions of the host cell and the latent HIV-1 integration event and position kinome profiling as a research tool to reveal novel molecular mechanisms that can eventually be targeted to therapeutically trigger HIV-1 reactivation.
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17
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Kaczmarek K, Morales A, Henderson AJ. T Cell Transcription Factors and Their Impact on HIV Expression. Virology (Auckl) 2013; 2013:41-47. [PMID: 24436634 PMCID: PMC3891646 DOI: 10.4137/vrt.s12147] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
By targeting CD4+ effector T cells, HIV has a dramatic impact on the depletion, expansion and function of the different polarized T cell subsets. The maturation of T cell lineages is in part driven by intrinsic transcription factors that potentially influence how efficiently HIV replicates. In this review, we explore whether transcription factors that are required for polarizing T cells influence HIV replication. In particular, we examine provirus transcription as well as the establishment and maintenance of HIV latency. Furthermore, it is suggested these factors may provide novel cell-specific therapeutic strategies for targeting the HIV latent reservoir.
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Affiliation(s)
- Katarzyna Kaczmarek
- Graduate Program in Molecular and Translational Medicine, Boston University School of Medicine, Boston, MA
| | - Ayana Morales
- Section of Infectious Diseases and Department of Medicine, Boston University School of Medicine, Boston, MA
| | - Andrew J Henderson
- Graduate Program in Molecular and Translational Medicine, Boston University School of Medicine, Boston, MA. ; Section of Infectious Diseases and Department of Medicine, Boston University School of Medicine, Boston, MA
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18
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Piddubna A, Chemych M. IL-4, IL-10, TNF-α profile and immunological changes in North-Eastern Ukrainian HIV-infected individuals. HIV & AIDS REVIEW 2013. [DOI: 10.1016/j.hivar.2013.07.005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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