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Herd CL, Mellet J, Mashingaidze T, Durandt C, Pepper MS. Consequences of HIV infection in the bone marrow niche. Front Immunol 2023; 14:1163012. [PMID: 37497228 PMCID: PMC10366613 DOI: 10.3389/fimmu.2023.1163012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2023] [Accepted: 06/21/2023] [Indexed: 07/28/2023] Open
Abstract
Dysregulation of the bone marrow niche resulting from the direct and indirect effects of HIV infection contributes to haematological abnormalities observed in HIV patients. The bone marrow niche is a complex, multicellular environment which functions primarily in the maintenance of haematopoietic stem/progenitor cells (HSPCs). These adult stem cells are responsible for replacing blood and immune cells over the course of a lifetime. Cells of the bone marrow niche support HSPCs and help to orchestrate the quiescence, self-renewal and differentiation of HSPCs through chemical and molecular signals and cell-cell interactions. This narrative review discusses the HIV-associated dysregulation of the bone marrow niche, as well as the susceptibility of HSPCs to infection by HIV.
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2
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Kim J, Behzadi ES, Nehring M, Carver S, Cowan SR, Conry MK, Rawlinson JE, VandeWoude S, Miller CA. Combination Antiretroviral Therapy and Immunophenotype of Feline Immunodeficiency Virus. Viruses 2023; 15:822. [PMID: 37112803 PMCID: PMC10146003 DOI: 10.3390/v15040822] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2023] [Revised: 03/17/2023] [Accepted: 03/22/2023] [Indexed: 04/29/2023] Open
Abstract
Feline Immunodeficiency Virus (FIV) causes progressive immune dysfunction in cats similar to human immunodeficiency virus (HIV) in humans. Although combination antiretroviral therapy (cART) is effective against HIV, there is no definitive therapy to improve clinical outcomes in cats with FIV. This study therefore evaluated pharmacokinetics and clinical outcomes of cART (2.5 mg/kg Dolutegravir; 20 mg/kg Tenofovir; 40 mg/kg Emtricitabine) in FIV-infected domestic cats. Specific pathogen free cats were experimentally infected with FIV and administered either cART or placebo treatments (n = 6 each) for 18 weeks, while n = 6 naïve uninfected cats served as controls. Blood, saliva, and fine needle aspirates from mandibular lymph nodes were collected to quantify viral and proviral loads via digital droplet PCR and to assess lymphocyte immunophenotypes by flow cytometry. cART improved blood dyscrasias in FIV-infected cats, which normalized by week 16, while placebo cats remained neutropenic, although no significant difference in viremia was observed in the blood or saliva. cART-treated cats exhibited a Th2 immunophenotype with increasing proportions of CD4+CCR4+ cells compared to placebo cats, and cART restored Th17 cells compared to placebo-treated cats. Of the cART drugs, dolutegravir was the most stable and long-lasting. These findings provide a critical insight into novel cART formulations in FIV-infected cats and highlight their role as a potential animal model to evaluate the impact of cART on lentiviral infection and immune dysregulation.
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Affiliation(s)
- Jeffrey Kim
- Comparative Medicine Research Unit, School of Medicine, University of Louisville, Louisville, KY 40292, USA
| | - Elisa S. Behzadi
- Department of Microbiology, Immunology, and Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO 80523, USA
| | - Mary Nehring
- Department of Microbiology, Immunology, and Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO 80523, USA
| | - Scott Carver
- School of Natural Sciences, University of Tasmania, Hobart, TAS 7001, Australia
| | - Shannon R. Cowan
- Department of Veterinary Pathobiology, Oklahoma State University, Stillwater, OK 74078, USA
| | - Megan K. Conry
- Department of Microbiology, Immunology, and Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO 80523, USA
| | - Jennifer E. Rawlinson
- Department of Clinical Sciences, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO 80523, USA
| | - Sue VandeWoude
- Department of Microbiology, Immunology, and Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO 80523, USA
| | - Craig A. Miller
- Department of Veterinary Pathobiology, Oklahoma State University, Stillwater, OK 74078, USA
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3
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T-cell evasion and invasion during HIV-1 infection: The role of HIV-1 Tat protein. Cell Immunol 2022; 377:104554. [DOI: 10.1016/j.cellimm.2022.104554] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2022] [Revised: 05/22/2022] [Accepted: 05/23/2022] [Indexed: 12/22/2022]
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4
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Expression Profile and Biological Role of Immune Checkpoints in Disease Progression of HIV/SIV Infection. Viruses 2022; 14:v14030581. [PMID: 35336991 PMCID: PMC8955100 DOI: 10.3390/v14030581] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2022] [Revised: 03/09/2022] [Accepted: 03/09/2022] [Indexed: 01/27/2023] Open
Abstract
During HIV/SIV infection, the upregulation of immune checkpoint (IC) markers, programmed cell death protein-1 (PD-1), cytotoxic T-lymphocyte-associated antigen-4 (CTLA-4), T cell immunoglobulin and ITIM domain (TIGIT), lymphocyte-activation gene-3 (LAG-3), T cell immunoglobulin and mucin domain-3 (Tim-3), CD160, 2B4 (CD244), and V-domain Ig suppressor of T cell activation (VISTA), can lead to chronic T cell exhaustion. These ICs play predominant roles in regulating the progression of HIV/SIV infection by mediating T cell responses as well as enriching latent viral reservoirs. It has been demonstrated that enhanced expression of ICs on CD4+ and CD8+ T cells could inhibit cell proliferation and cytokine production. Overexpression of ICs on CD4+ T cells could also format and prolong HIV/SIV persistence. IC blockers have shown promising clinical results in HIV therapy, implying that targeting ICs may optimize antiretroviral therapy in the context of HIV suppression. Here, we systematically review the expression profile, biological regulation, and therapeutic efficacy of targeted immune checkpoints in HIV/SIV infection.
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5
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Beckford-Vera DR, Flavell RR, Seo Y, Martinez-Ortiz E, Aslam M, Thanh C, Fehrman E, Pardons M, Kumar S, Deitchman AN, Ravanfar V, Schulte B, Wu IWK, Pan T, Reeves JD, Nixon CC, Iyer NS, Torres L, Munter SE, Hyunh T, Petropoulos CJ, Hoh R, Franc BL, Gama L, Koup RA, Mascola JR, Chomont N, Deeks SG, VanBrocklin HF, Henrich TJ. First-in-human immunoPET imaging of HIV-1 infection using 89Zr-labeled VRC01 broadly neutralizing antibody. Nat Commun 2022; 13:1219. [PMID: 35264559 PMCID: PMC8907355 DOI: 10.1038/s41467-022-28727-5] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2021] [Accepted: 02/01/2022] [Indexed: 11/09/2022] Open
Abstract
A major obstacle to achieving long-term antiretroviral (ART) free remission or functional cure of HIV infection is the presence of persistently infected cells that establish a long-lived viral reservoir. HIV largely resides in anatomical regions that are inaccessible to routine sampling, however, and non-invasive methods to understand the longitudinal tissue-wide burden of HIV persistence are urgently needed. Positron emission tomography (PET) imaging is a promising strategy to identify and characterize the tissue-wide burden of HIV. Here, we assess the efficacy of using immunoPET imaging to characterize HIV reservoirs and identify anatomical foci of persistent viral transcriptional activity using a radiolabeled HIV Env-specific broadly neutralizing antibody, 89Zr-VRC01, in HIV-infected individuals with detectable viremia and on suppressive ART compared to uninfected controls (NCT03729752). We also assess the relationship between PET tracer uptake in tissues and timing of ART initiation and direct HIV protein expression in CD4 T cells obtained from lymph node biopsies. We observe significant increases in 89Zr-VRC01 uptake in various tissues (including lymph nodes and gut) in HIV-infected individuals with detectable viremia (N = 5) and on suppressive ART (N = 5) compared to uninfected controls (N = 5). Importantly, PET tracer uptake in inguinal lymph nodes in viremic and ART-suppressed participants significantly and positively correlates with HIV protein expression measured directly in tissue. Our strategy may allow non-invasive longitudinal characterization of residual HIV infection and lays the framework for the development of immunoPET imaging in a variety of other infectious diseases.
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Affiliation(s)
- Denis R Beckford-Vera
- Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, CA, USA
| | - Robert R Flavell
- Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, CA, USA
| | - Youngho Seo
- Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, CA, USA
| | - Enrique Martinez-Ortiz
- Division of HIV, Infectious Diseases and Global Medicine, University of California San Francisco, San Francisco, CA, USA
| | - Maya Aslam
- Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, CA, USA
| | - Cassandra Thanh
- Division of Experimental Medicine, University of California San Francisco, San Francisco, CA, USA
| | - Emily Fehrman
- Division of HIV, Infectious Diseases and Global Medicine, University of California San Francisco, San Francisco, CA, USA
| | - Marion Pardons
- Department of Microbiology, Infectiology and Immunology, Centre de Recherche du CHUM, Université de Montréal, Montreal, QC, Canada
| | - Shreya Kumar
- Division of Experimental Medicine, University of California San Francisco, San Francisco, CA, USA
| | - Amelia N Deitchman
- Department of Clinical Pharmacy, University of California, San Francisco, USA
| | - Vahid Ravanfar
- Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, CA, USA
| | - Brailee Schulte
- Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, CA, USA
| | - I-Wei Katherine Wu
- Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, CA, USA
| | - Tony Pan
- Division of Experimental Medicine, University of California San Francisco, San Francisco, CA, USA
| | - Jacqueline D Reeves
- Division of Experimental Medicine, University of California San Francisco, San Francisco, CA, USA
| | - Christopher C Nixon
- Division of Experimental Medicine, University of California San Francisco, San Francisco, CA, USA
| | - Nikita S Iyer
- Division of Experimental Medicine, University of California San Francisco, San Francisco, CA, USA
| | - Leonel Torres
- Division of Experimental Medicine, University of California San Francisco, San Francisco, CA, USA
| | - Sadie E Munter
- Division of Experimental Medicine, University of California San Francisco, San Francisco, CA, USA
| | - Tony Hyunh
- Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, CA, USA
| | - Christos J Petropoulos
- Monogram Biosciences, Inc., Laboratory Corporation of America, South San Francisco, San Francisco, USA
| | - Rebecca Hoh
- Division of HIV, Infectious Diseases and Global Medicine, University of California San Francisco, San Francisco, CA, USA
| | - Benjamin L Franc
- Department of Radiology, Stanford University, Palo Alto, CA, USA
| | - Lucio Gama
- Vaccine Research Center, National Institute for Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Richard A Koup
- Vaccine Research Center, National Institute for Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - John R Mascola
- Vaccine Research Center, National Institute for Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Nicolas Chomont
- Department of Microbiology, Infectiology and Immunology, Centre de Recherche du CHUM, Université de Montréal, Montreal, QC, Canada
| | - Steven G Deeks
- Division of HIV, Infectious Diseases and Global Medicine, University of California San Francisco, San Francisco, CA, USA
| | - Henry F VanBrocklin
- Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, CA, USA.
| | - Timothy J Henrich
- Division of Experimental Medicine, University of California San Francisco, San Francisco, CA, USA.
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6
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Le Hingrat Q, Sereti I, Landay AL, Pandrea I, Apetrei C. The Hitchhiker Guide to CD4 + T-Cell Depletion in Lentiviral Infection. A Critical Review of the Dynamics of the CD4 + T Cells in SIV and HIV Infection. Front Immunol 2021; 12:695674. [PMID: 34367156 PMCID: PMC8336601 DOI: 10.3389/fimmu.2021.695674] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2021] [Accepted: 06/09/2021] [Indexed: 01/02/2023] Open
Abstract
CD4+ T-cell depletion is pathognomonic for AIDS in both HIV and simian immunodeficiency virus (SIV) infections. It occurs early, is massive at mucosal sites, and is not entirely reverted by antiretroviral therapy (ART), particularly if initiated when T-cell functions are compromised. HIV/SIV infect and kill activated CCR5-expressing memory and effector CD4+ T-cells from the intestinal lamina propria. Acute CD4+ T-cell depletion is substantial in progressive, nonprogressive and controlled infections. Clinical outcome is predicted by the mucosal CD4+ T-cell recovery during chronic infection, with no recovery occurring in rapid progressors, and partial, transient recovery, the degree of which depends on the virus control, in normal and long-term progressors. The nonprogressive infection of African nonhuman primate SIV hosts is characterized by partial mucosal CD4+ T-cell restoration, despite high viral replication. Complete, albeit very slow, recovery of mucosal CD4+ T-cells occurs in controllers. Early ART does not prevent acute mucosal CD4+ T-cell depletion, yet it greatly improves their restoration, sometimes to preinfection levels. Comparative studies of the different models of SIV infection support a critical role of immune activation/inflammation (IA/INFL), in addition to viral replication, in CD4+ T-cell depletion, with immune restoration occurring only when these parameters are kept at bay. CD4+ T-cell depletion is persistent, and the recovery is very slow, even when both the virus and IA/INFL are completely controlled. Nevertheless, partial mucosal CD4+ T-cell recovery is sufficient for a healthy life in natural hosts. Cell death and loss of CD4+ T-cell subsets critical for gut health contribute to mucosal inflammation and enteropathy, which weaken the mucosal barrier, leading to microbial translocation, a major driver of IA/INFL. In turn, IA/INFL trigger CD4+ T-cells to become either viral targets or apoptotic, fueling their loss. CD4+ T-cell depletion also drives opportunistic infections, cancers, and comorbidities. It is thus critical to preserve CD4+ T cells (through early ART) during HIV/SIV infection. Even in early-treated subjects, residual IA/INFL can persist, preventing/delaying CD4+ T-cell restoration. New therapeutic strategies limiting mucosal pathology, microbial translocation and IA/INFL, to improve CD4+ T-cell recovery and the overall HIV prognosis are needed, and SIV models are extensively used to this goal.
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Affiliation(s)
- Quentin Le Hingrat
- Division of Infectious Diseases, DOM, School of Medicine, University of Pittsburgh, Pittsburgh, PA, United States
| | - Irini Sereti
- HIV Pathogenesis Section, Laboratory of Immunoregulation, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, United States
| | - Alan L Landay
- Department of Internal Medicine, Rush University Medical Center, Chicago, IL, United States
| | - Ivona Pandrea
- Department of Pathology, School of Medicine, University of Pittsburgh, Pittsburgh, PA, United States.,Department of Infectious Diseases and Immunology, Graduate School of Public Health, University of Pittsburgh, Pittsburgh, PA, United States
| | - Cristian Apetrei
- Division of Infectious Diseases, DOM, School of Medicine, University of Pittsburgh, Pittsburgh, PA, United States.,Department of Infectious Diseases and Immunology, Graduate School of Public Health, University of Pittsburgh, Pittsburgh, PA, United States
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7
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León-Rivera R, Morsey B, Niu M, Fox HS, Berman JW. Interactions of Monocytes, HIV, and ART Identified by an Innovative scRNAseq Pipeline: Pathways to Reservoirs and HIV-Associated Comorbidities. mBio 2020; 11:e01037-20. [PMID: 32723919 PMCID: PMC7387797 DOI: 10.1128/mbio.01037-20] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2020] [Accepted: 06/22/2020] [Indexed: 12/31/2022] Open
Abstract
HIV reservoirs persist despite successful antiretroviral therapy (ART) and are a major obstacle to the eradication and cure of HIV. The mature monocyte subset, CD14+CD16+, contributes to viral reservoirs and HIV-associated comorbidities. Only a subset of monocytes harbors HIV (HIV+), while the rest remain uninfected, exposed cells (HIVexp). We developed an innovative single cell RNA sequencing (scRNAseq) pipeline that detects HIV and host transcripts simultaneously, enabling us to examine differences between HIV+ and HIVexp mature monocytes. Using this, we characterized uninfected, HIV+, and HIVexp primary human mature monocytes with and without ART. We showed that HIV+ mature monocytes do not form their own cluster separately from HIVexp but can be distinguished by significant differential gene expression. We found that ART decreased levels of unspliced HIV transcripts potentially by modulating host transcriptional regulators shown to decrease viral infection and replication. We also identified and characterized mature monocyte subpopulations differentially impacted by HIV and ART. We identified genes dysregulated by ART in HIVexp monocytes compared to their uninfected counterpart and, of interest, the junctional protein ALCAM, suggesting that ART impacts monocyte functions. Our data provide a novel method for simultaneous detection of HIV and host transcripts. We identify potential targets, such as those genes whose expression is increased in HIV+ mature monocytes compared to HIVexp, to block their entry into tissues, preventing establishment/replenishment of HIV reservoirs even with ART, thereby reducing and/or eliminating viral burden and HIV-associated comorbidities. Our data also highlight the heterogeneity of mature monocyte subsets and their potential contributions to HIV pathogenesis in the ART era.IMPORTANCE HIV enters tissues early after infection, leading to establishment and persistence of HIV reservoirs despite antiretroviral therapy (ART). Viral reservoirs are a major obstacle to the eradication and cure of HIV. CD14+CD16+ (mature) monocytes may contribute to establishment and reseeding of reservoirs. A subset of monocytes, consisting mainly of CD14+CD16+ cells, harbors HIV (HIV+), while the rest remain uninfected, exposed cells (HIVexp). It is important to identify cells harboring virus to eliminate reservoirs. Using an innovative single-cell RNA sequencing (scRNAseq) pipeline to detect HIV and host transcripts simultaneously, we characterized HIV+ and HIVexp primary human mature monocytes with and without ART. HIV+ mature monocytes are not a unique subpopulation but rather can be distinguished from HIVexp by differential gene expression. We characterized mature monocyte subpopulations differently impacted by HIV and ART, highlighting their potential contributions to HIV-associated comorbidities. Our data propose therapeutic targets to block HIV+ monocyte entry into tissues, preventing establishment and replenishment of reservoirs even with ART.
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Affiliation(s)
- Rosiris León-Rivera
- Department of Pathology, Albert Einstein College of Medicine, Bronx, New York, USA
| | - Brenda Morsey
- Department of Neurological Sciences, University of Nebraska Medical Center, Omaha, Nebraska, USA
| | - Meng Niu
- Department of Genetics, Cell Biology & Anatomy, University of Nebraska Medical Center, Omaha, Nebraska, USA
| | - Howard S Fox
- Department of Neurological Sciences, University of Nebraska Medical Center, Omaha, Nebraska, USA
| | - Joan W Berman
- Department of Pathology, Albert Einstein College of Medicine, Bronx, New York, USA
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8
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Chen H, Moussa M, Catalfamo M. The Role of Immunomodulatory Receptors in the Pathogenesis of HIV Infection: A Therapeutic Opportunity for HIV Cure? Front Immunol 2020; 11:1223. [PMID: 32714317 PMCID: PMC7343933 DOI: 10.3389/fimmu.2020.01223] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2019] [Accepted: 05/15/2020] [Indexed: 12/12/2022] Open
Abstract
Immune activation is the hallmark of HIV infection and plays a role in the pathogenesis of the disease. In the context of suppressed HIV RNA replication by combination antiretroviral therapy (cART), there remains immune activation which is associated to the HIV reservoirs. Persistent virus contributes to a sustained inflammatory environment promoting accumulation of "activated/exhausted" T cells with diminished effector function. These T cells show increased expression of immunomodulatory receptors including Programmed cell death protein (PD1), Cytotoxic T Lymphocyte Associated Protein 4 (CTLA4), Lymphocyte activation gene 3 (LAG3), T cell immunoglobulin and ITIM domain (TIGIT), T cell immunoglobulin and mucin domain containing 3 (TIM3) among others. More importantly, recent reports had demonstrated that, HIV infected T cells express checkpoint receptors, contributing to their survival and promoting maintenance of the viral reservoir. Therapeutic strategies are focused on viral reservoir elimination and/or those to achieve sustained cART-free virologic remission. In this review, we will discuss the immunological basis and the latest advances of the use of checkpoint inhibitors to treat HIV infection.
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Affiliation(s)
- Hui Chen
- Department of Microbiology and Immunology, Georgetown University School of Medicine, Washington, DC, United States
- CMRS/Laboratory of Immunoregulation, National Institutes of Allergy and Infectious Diseases, Bethesda, MD, United States
| | - Maha Moussa
- Department of Microbiology and Immunology, Georgetown University School of Medicine, Washington, DC, United States
| | - Marta Catalfamo
- Department of Microbiology and Immunology, Georgetown University School of Medicine, Washington, DC, United States
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Ladinsky MS, Khamaikawin W, Jung Y, Lin S, Lam J, An DS, Bjorkman PJ, Kieffer C. Mechanisms of virus dissemination in bone marrow of HIV-1-infected humanized BLT mice. eLife 2019; 8:46916. [PMID: 31657719 PMCID: PMC6839903 DOI: 10.7554/elife.46916] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2019] [Accepted: 10/27/2019] [Indexed: 02/06/2023] Open
Abstract
Immune progenitor cells differentiate in bone marrow (BM) and then migrate to tissues. HIV-1 infects multiple BM cell types, but virus dissemination within BM has been poorly understood. We used light microscopy and electron tomography to elucidate mechanisms of HIV-1 dissemination within BM of HIV-1–infected BM/liver/thymus (BLT) mice. Tissue clearing combined with confocal and light sheet fluorescence microscopy revealed distinct populations of HIV-1 p24-producing cells in BM early after infection, and quantification of these populations identified macrophages as the principal subset of virus-producing cells in BM over time. Electron tomography demonstrated three modes of HIV-1 dissemination in BM: (i) semi-synchronous budding from T-cell and macrophage membranes, (ii) mature virus association with virus-producing T-cell uropods contacting putative target cells, and (iii) macrophages engulfing HIV-1–producing T-cells and producing virus within enclosed intracellular compartments that fused to invaginations with access to the extracellular space. These results illustrate mechanisms by which the specialized environment of the BM can promote virus spread locally and to distant lymphoid tissues.
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Affiliation(s)
- Mark S Ladinsky
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, United States
| | - Wannisa Khamaikawin
- School of Nursing, UCLA AIDS Institute, University of California, Los Angeles, Los Angeles, United States
| | - Yujin Jung
- School of Nursing, UCLA AIDS Institute, University of California, Los Angeles, Los Angeles, United States
| | - Samantha Lin
- School of Nursing, UCLA AIDS Institute, University of California, Los Angeles, Los Angeles, United States
| | - Jennifer Lam
- School of Nursing, UCLA AIDS Institute, University of California, Los Angeles, Los Angeles, United States
| | - Dong Sung An
- School of Nursing, UCLA AIDS Institute, University of California, Los Angeles, Los Angeles, United States
| | - Pamela J Bjorkman
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, United States
| | - Collin Kieffer
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, United States
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10
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Fingolimod retains cytolytic T cells and limits T follicular helper cell infection in lymphoid sites of SIV persistence. PLoS Pathog 2019; 15:e1008081. [PMID: 31626660 PMCID: PMC6834281 DOI: 10.1371/journal.ppat.1008081] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2019] [Revised: 11/06/2019] [Accepted: 09/13/2019] [Indexed: 01/29/2023] Open
Abstract
Lymph nodes (LN) and their resident T follicular helper CD4+ T cells (Tfh) are a critical site for HIV replication and persistence. Therefore, optimizing antiviral activity in lymphoid tissues will be needed to reduce or eliminate the HIV reservoir. In this study, we retained effector immune cells in LN of cART-suppressed, SIV-infected rhesus macaques by treatment with the lysophospholipid sphingosine-1 phosphate receptor modulator FTY720 (fingolimod). FTY720 was remarkably effective in reducing circulating CD4+ and CD8+ T cells, including those with cytolytic potential, and in increasing the number of these T cells retained in LN, as determined directly in situ by histocytometry and immunohistochemistry. The FTY720-induced inhibition of T cell egress from LN resulted in a measurable decrease of SIV-DNA content in blood as well as in LN Tfh cells in most treated animals. In conclusion, FTY720 administration has the potential to limit viral persistence, including in the critical Tfh cellular reservoir. These findings provide rationale for strategies designed to retain antiviral T cells in lymphoid tissues to target HIV remission. FTY720 (fingolimod), a drug approved by the FDA for treatment of multiple sclerosis, blocks the egress of lymphocytes from the lymph node (LN). To determine whether FTY720 retention activity could improve cytolytic responses in the LN and affect SIV persistence, we studied for the first time tolerability and biological activity of two doses of FTY720 in cART-suppressed, SIV-infected rhesus macaques. FTY720 was remarkably effective in reducing circulating CD4+ and CD8+ T cells, including those with cytolytic potential, and in increasing the number of cytolytic T cells in LN. FTY720 administration reduced SIV-DNA content in blood as well as in LN Tfh cells in most of the animals. These results suggest that FTY720 limits viral persistence, including Tfh cellular reservoir, by increasing the number of cytolytic cells in the LN, critical site for HIV/SIV replication and persistence.
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