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Karsten CB, Buettner FFR, Cajic S, Nehlmeier I, Roshani B, Klippert A, Sauermann U, Stolte-Leeb N, Reichl U, Gerardy-Schahn R, Rapp E, Stahl-Hennig C, Pöhlmann S. Macrophage- and CD4+ T cell-derived SIV differ in glycosylation, infectivity and neutralization sensitivity. PLoS Pathog 2024; 20:e1012190. [PMID: 38805549 PMCID: PMC11161069 DOI: 10.1371/journal.ppat.1012190] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2024] [Revised: 06/07/2024] [Accepted: 04/11/2024] [Indexed: 05/30/2024] Open
Abstract
The human immunodeficiency virus (HIV) envelope protein (Env) mediates viral entry into host cells and is the primary target for the humoral immune response. Env is extensively glycosylated, and these glycans shield underlying epitopes from neutralizing antibodies. The glycosylation of Env is influenced by the type of host cell in which the virus is produced. Thus, HIV is distinctly glycosylated by CD4+ T cells, the major target cells, and macrophages. However, the specific differences in glycosylation between viruses produced in these cell types have not been explored at the molecular level. Moreover, it remains unclear whether the production of HIV in CD4+ T cells or macrophages affects the efficiency of viral spread and resistance to neutralization. To address these questions, we employed the simian immunodeficiency virus (SIV) model. Glycan analysis implied higher relative levels of oligomannose-type N-glycans in SIV from CD4+ T cells (T-SIV) compared to SIV from macrophages (M-SIV), and the complex-type N-glycans profiles seem to differ between the two viruses. Notably, M-SIV demonstrated greater infectivity than T-SIV, even when accounting for Env incorporation, suggesting that host cell-dependent factors influence infectivity. Further, M-SIV was more efficiently disseminated by HIV binding cellular lectins. We also evaluated the influence of cell type-dependent differences on SIV's vulnerability to carbohydrate binding agents (CBAs) and neutralizing antibodies. T-SIV demonstrated greater susceptibility to mannose-specific CBAs, possibly due to its elevated expression of oligomannose-type N-glycans. In contrast, M-SIV exhibited higher susceptibility to neutralizing sera in comparison to T-SIV. These findings underscore the importance of host cell-dependent attributes of SIV, such as glycosylation, in shaping both infectivity and the potential effectiveness of intervention strategies.
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Affiliation(s)
- Christina B. Karsten
- Institute for the Research on HIV and AIDS-associated Diseases, University Hospital Essen, University of Duisburg-Essen, Essen, Germany
| | - Falk F. R. Buettner
- Institute of Clinical Biochemistry, Hannover Medical School, Hannover, Germany
- Proteomics, Institute of Theoretical Medicine, Faculty of Medicine, University of Augsburg, Augsburg, Germany
| | - Samanta Cajic
- glyXera GmbH, Magdeburg, Germany
- Bioprocess Engineering Group, Max Planck Institute for Dynamics of Complex Technical Systems, Magdeburg, Germany
| | - Inga Nehlmeier
- Infection Biology Unit, German Primate Center–Leibniz Institute for Primate Research, Göttingen, Germany
| | - Berit Roshani
- Unit of Infection Models, German Primate Center–Leibniz Institute for Primate Research, Göttingen, Germany
| | | | - Ulrike Sauermann
- Unit of Infection Models, German Primate Center–Leibniz Institute for Primate Research, Göttingen, Germany
| | - Nicole Stolte-Leeb
- Unit of Infection Models, German Primate Center–Leibniz Institute for Primate Research, Göttingen, Germany
| | - Udo Reichl
- Bioprocess Engineering Group, Max Planck Institute for Dynamics of Complex Technical Systems, Magdeburg, Germany
| | - Rita Gerardy-Schahn
- Institute of Clinical Biochemistry, Hannover Medical School, Hannover, Germany
| | - Erdmann Rapp
- glyXera GmbH, Magdeburg, Germany
- Bioprocess Engineering Group, Max Planck Institute for Dynamics of Complex Technical Systems, Magdeburg, Germany
| | - Christiane Stahl-Hennig
- Unit of Infection Models, German Primate Center–Leibniz Institute for Primate Research, Göttingen, Germany
| | - Stefan Pöhlmann
- Infection Biology Unit, German Primate Center–Leibniz Institute for Primate Research, Göttingen, Germany
- Faculty of Biology and Psychology, Georg-August-University Göttingen, Göttingen, Germany
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Okafo G, Valdebenito S, Donoso M, Luu R, Ajasin D, Prideaux B, Gorantla S, Eugenin EA. Role of Tunneling Nanotube-like Structures during the Early Events of HIV Infection: Novel Features of Tissue Compartmentalization and Mechanism of HIV Spread. THE JOURNAL OF IMMUNOLOGY 2020; 205:2726-2741. [PMID: 33037140 DOI: 10.4049/jimmunol.2000803] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/07/2020] [Accepted: 09/04/2020] [Indexed: 12/11/2022]
Abstract
HIV has become a chronic disease despite the effective use of antiretroviral therapy (ART). However, the mechanisms of tissue colonization, viral evolution, generation of viral reservoirs, and compartmentalization are still a matter of debate due to the challenges involved in examining early events of infection at the cellular and molecular level. Thus, there is still an urgent need to explore these areas to develop effective HIV cure strategies. In this study, we describe the early events of tissue colonization and compartmentalization as well as the role of tunneling nanotube-like structures during viral spread in the presence and absence of effective antiretroviral treatment. To examine these mechanisms, NOD/SCID IL-2 RG-/- humanized mice were either directly infected with HIVADA or with low numbers of HIVADA-infected leukocytes to limit tissue colonization in the presence and absence of TAK779, an effective CCR5 blocker of HIV entry. We identify that viral seeding in tissues occurs early in a tissue- and cell type-specific manner (24-72 h). Reduction in systemic HIV replication by TAK779 treatment did not affect tissue seeding or spreading, despite reduced systemic viral replication. Tissue-associated HIV-infected cells had different properties than cells in the circulation because the virus continues to spread in tissues in a tunneling nanotube-like structure-dependent manner, despite ART. Thus, understanding these mechanisms can provide new approaches to enhance the efficacy of existing ART and HIV infection cure strategies.
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Affiliation(s)
- George Okafo
- GO Pharma Consulting Ltd., Welwyn AL6 0QT, United Kingdom
| | - Silvana Valdebenito
- Department of Neuroscience, Cell Biology and Anatomy, University of Texas Medical Branch, Galveston, TX 77555; and
| | - Maribel Donoso
- Department of Neuroscience, Cell Biology and Anatomy, University of Texas Medical Branch, Galveston, TX 77555; and
| | - Ross Luu
- Department of Neuroscience, Cell Biology and Anatomy, University of Texas Medical Branch, Galveston, TX 77555; and
| | - David Ajasin
- Department of Neuroscience, Cell Biology and Anatomy, University of Texas Medical Branch, Galveston, TX 77555; and
| | - Brendan Prideaux
- Department of Neuroscience, Cell Biology and Anatomy, University of Texas Medical Branch, Galveston, TX 77555; and
| | - Santhi Gorantla
- Department of Pharmacology and Experimental Neuroscience, College of Medicine, University of Nebraska Medical Center, Omaha, NE 68198
| | - Eliseo A Eugenin
- Department of Neuroscience, Cell Biology and Anatomy, University of Texas Medical Branch, Galveston, TX 77555; and
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3
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Moar P, Sushmita K, Kateriya S, Tandon R. Transcriptional profiling indicates cAMP-driven reversal of HIV latency in monocytes occurs via transcription factor SP-1. Virology 2020; 542:40-53. [PMID: 32056667 DOI: 10.1016/j.virol.2020.01.006] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2019] [Revised: 01/11/2020] [Accepted: 01/14/2020] [Indexed: 01/16/2023]
Abstract
Latent HIV reservoir is a major barrier to absolute HIV cure. Studies on latency reversal agents (LRA) have by far focused mainly on CD4+ T-lymphocytes, while myeloid reservoirs remain under-represented despite their persistence and key contribution to HIV pathogenesis. cAMP has been shown to increase HIV-1 transcription in latently-infected monocytes/macrophages. In this communication, we explored the potential of commercially available pharmacological drugs and phosphodiesterase inhibitors to reactivate HIV in latently-infected monocytic cell-line, U1. We showed that increased levels of intracellular cAMP reverse HIV latency in vitro, which is specific to cells of the myeloid lineage. High throughput RNA-seq analysis revealed that cAMP modulates transcriptional profile of latently HIV-infected cells and provides favourable cellular environment for HIV to produce viral proteins. This reactivation of latent HIV was inhibited by Mithramycin A, a selective Sp1 inhibitor, indicating that the reversal of HIV latency in monocytes is driven by transcription factor Sp1.
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Affiliation(s)
- Preeti Moar
- Laboratory of AIDS Research and Immunology, School of Biotechnology, Jawaharlal Nehru University, New Delhi, India
| | - Kumari Sushmita
- Laboratory of Optobiology, School of Biotechnology, Jawaharlal Nehru University, New Delhi, India
| | - Suneel Kateriya
- Laboratory of Optobiology, School of Biotechnology, Jawaharlal Nehru University, New Delhi, India
| | - Ravi Tandon
- Laboratory of AIDS Research and Immunology, School of Biotechnology, Jawaharlal Nehru University, New Delhi, India.
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4
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Abstract
PURPOSE OF REVIEW Gallant efforts are ongoing to achieve sustained antiretroviral therapy (ART)-free HIV remission in the HIV-infected person; however, most, if not all, current human clinical studies have primarily focused these efforts on targeting viral persistence in CD4 T cells in blood and tissue sanctuaries. The lack of myeloid centered HIV clinical trials, either as primary or secondary end points, has hindered our understanding of the contribution of myeloid cells in unsuccessful trials but may also guide successes in future HIV eradication clinical strategies. RECENT FINDINGS Recent advances have highlighted the importance of myeloid reservoirs as sanctuaries of HIV persistence and therefore may partially be responsible for viral recrudescence following ART treatment interruption in several clinical trials where HIV was not detectable or recovered from CD4 T cells. Given these findings, novel innovative therapeutic approaches specifically focused on HIV clearance in myeloid cell populations need to be vigorously pursued if we are to achieve additional cases of sustained ART-free remission. This review will highlight new research efforts defining myeloid persistence and recent advances in HIV remission and cure trials that would be relevant in targeting this compartment and make an argument as to their clinical relevancy as we progress towards sustained ART-free HIV remission in all HIV-infected persons.
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Affiliation(s)
- Brooks I Mitchell
- John A. Burns School of Medicine, University of Hawaii, 651 Ilalo St., Honolulu, HI, USA
| | - Elizabeth I Laws
- John A. Burns School of Medicine, University of Hawaii, 651 Ilalo St., Honolulu, HI, USA
| | - Lishomwa C Ndhlovu
- John A. Burns School of Medicine, University of Hawaii, 651 Ilalo St., Honolulu, HI, USA.
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Basova L, Najera JA, Bortell N, Wang D, Moya R, Lindsey A, Semenova S, Ellis RJ, Marcondes MCG. Dopamine and its receptors play a role in the modulation of CCR5 expression in innate immune cells following exposure to Methamphetamine: Implications to HIV infection. PLoS One 2018; 13:e0199861. [PMID: 29944719 PMCID: PMC6019408 DOI: 10.1371/journal.pone.0199861] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2017] [Accepted: 06/14/2018] [Indexed: 01/08/2023] Open
Abstract
The Human Immunodeficiency Virus (HIV) infects cells in the Central Nervous System (CNS), where the access of antiretrovirals and antibodies that can kill the virus may be challenging. As a result of the early HIV entry in the brain, infected individuals develop inflammation and neurological deficits at various levels, which are aggravated by drugs of abuse. In the non-human primate model of HIV, we have previously shown that drugs of abuse such as Methamphetamine (Meth) increase brain viral load in correlation with a higher number of CCR5-expressing myeloid cells. CCR5 is a chemokine receptor that may be involved in increasing inflammation, but also, it is a co-receptor for viral entry into target cells. CCR5-expressing myeloid cells are the main targets of HIV in the CNS. Thus, the identification of factors and mechanisms that impact the expression of CCR5 in the brain is critical, as changes in CCR5 levels may affect the infection in the brain. Using a well-characterized in vitro system, with the THP1 human macrophage cell line, we have investigated the hypothesis that the expression of CCR5 is acutely affected by Meth, and examined pathways by which this effect could happen. We found that Meth plays a direct role by regulating the abundance and nuclear translocation of transcription factors with binding sites in the CCR5 promoter. However, we found that the main factor that modifies the CCR5 gene promoter at the epigenetic level towards transcription is Dopamine (DA), a neurotransmitter that is produced primarily in brain regions that are rich in dopaminergic neurons. In THP1 cells, the effect of DA on innate immune CCR5 transcription was mediated by DA receptors (DRDs), mainly DRD4. We also identified a role for DRD1 in suppressing CCR5 expression in this myeloid cell system, with potential implications for therapy. The effect of DA on innate immune CCR5 expression was also detectable on the cell surface during acute time-points, using low doses. In addition, HIV Tat acted by enhancing the surface expression of CCR5, in spite of its poor effect on transcription. Overall, our data suggests that the exposure of myeloid cells to Meth in the context of presence of HIV peptides such as Tat, may affect the number of HIV targets by modulating CCR5 expression, through a combination of DA-dependent and–independent mechanisms. Other drugs that increase DA may affect similar mechanisms. The implications of these epigenetic and translational mechanisms in enhancing HIV infection in the brain and elsewhere are demonstrated.
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Affiliation(s)
- Liana Basova
- San Diego Biomedical Research Institute, San Diego, CA, United States of America
- Department of Neurosciences, The Scripps Research Institute, La Jolla, CA, United States of America
| | - Julia A. Najera
- Department of Neurosciences, The Scripps Research Institute, La Jolla, CA, United States of America
| | - Nikki Bortell
- Department of Neurosciences, The Scripps Research Institute, La Jolla, CA, United States of America
| | - Di Wang
- Department of Neurosciences, The Scripps Research Institute, La Jolla, CA, United States of America
- University of California San Diego, Department of Psychiatry, San Diego, CA, United States of America
| | - Rosita Moya
- San Diego Biomedical Research Institute, San Diego, CA, United States of America
| | - Alexander Lindsey
- San Diego Biomedical Research Institute, San Diego, CA, United States of America
| | - Svetlana Semenova
- University of California San Diego, Department of Psychiatry, San Diego, CA, United States of America
| | - Ronald J. Ellis
- University of California San Diego, Department of Psychiatry, San Diego, CA, United States of America
| | - Maria Cecilia Garibaldi Marcondes
- San Diego Biomedical Research Institute, San Diego, CA, United States of America
- Department of Neurosciences, The Scripps Research Institute, La Jolla, CA, United States of America
- * E-mail:
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6
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Abstract
PURPOSE OF REVIEW A central question for the HIV cure field is to determine new ways to target clinically relevant, latently and actively replicating HIV-infected cells beyond resting memory CD4 T cells, particularly in anatomical areas of low drug penetrability. RECENT FINDINGS HIV eradication strategies being positioned for targeting HIV for extinction in the CD4 T-cell compartment may also show promise in non-CD4 T-cells reservoirs. Furthermore, several exciting novel therapeutic approaches specifically focused on HIV clearance from non-CD4 T-cell populations are being developed. SUMMARY Although reservoir validity in these non-CD4 T cells continues to remain debated, this review will highlight recent advances and make an argument as to their clinical relevancy as we progress towards an HIV cure.
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7
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Wang B, Wang Y, Frabutt DA, Zhang X, Yao X, Hu D, Zhang Z, Liu C, Zheng S, Xiang SH, Zheng YH. Mechanistic understanding of N-glycosylation in Ebola virus glycoprotein maturation and function. J Biol Chem 2017; 292:5860-5870. [PMID: 28196864 DOI: 10.1074/jbc.m116.768168] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2016] [Revised: 02/12/2017] [Indexed: 01/04/2023] Open
Abstract
The Ebola virus (EBOV) trimeric envelope glycoprotein (GP) precursors are cleaved into the receptor-binding GP1 and the fusion-mediating GP2 subunits and incorporated into virions to initiate infection. GP1 and GP2 form heterodimers that have 15 or two N-glycosylation sites (NGSs), respectively. Here we investigated the mechanism of how N-glycosylation contributes to GP expression, maturation, and function. As reported before, we found that, although GP1 NGSs are not critical, the two GP2 NGSs, Asn563 and Asn618, are essential for GP function. Further analysis uncovered that Asn563 and Asn618 regulate GP processing, demannosylation, oligomerization, and conformation. Consequently, these two NGSs are required for GP incorporation into EBOV-like particles and HIV type 1 (HIV-1) pseudovirions and determine viral transduction efficiency. Using CRISPR/Cas9 technology, we knocked out the two classical endoplasmic reticulum chaperones calnexin (CNX) and/or calreticulin (CRT) and found that both CNX and CRT increase GP expression. Nevertheless, NGSs are not required for the GP interaction with CNX or CRT. Together, we conclude that, although Asn563 and Asn618 are not required for EBOV GP expression, they synergistically regulate its maturation, which determines its functionality.
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Affiliation(s)
- Bin Wang
- From the Harbin Veterinary Research Institute, CAAS-Michigan State University Joint Laboratory of Innate Immunity, State Key Laboratory of Veterinary Biotechnology, Chinese Academy of Agricultural Sciences, Harbin 150059, China
| | - Yujie Wang
- From the Harbin Veterinary Research Institute, CAAS-Michigan State University Joint Laboratory of Innate Immunity, State Key Laboratory of Veterinary Biotechnology, Chinese Academy of Agricultural Sciences, Harbin 150059, China
| | - Dylan A Frabutt
- the Department of Microbiology and Molecular Genetics, Michigan State University, East Lansing, Michigan 48824
| | - Xihe Zhang
- the Department of Microbiology and Molecular Genetics, Michigan State University, East Lansing, Michigan 48824
| | - Xiaoyu Yao
- From the Harbin Veterinary Research Institute, CAAS-Michigan State University Joint Laboratory of Innate Immunity, State Key Laboratory of Veterinary Biotechnology, Chinese Academy of Agricultural Sciences, Harbin 150059, China
| | - Dan Hu
- From the Harbin Veterinary Research Institute, CAAS-Michigan State University Joint Laboratory of Innate Immunity, State Key Laboratory of Veterinary Biotechnology, Chinese Academy of Agricultural Sciences, Harbin 150059, China
| | - Zhuo Zhang
- From the Harbin Veterinary Research Institute, CAAS-Michigan State University Joint Laboratory of Innate Immunity, State Key Laboratory of Veterinary Biotechnology, Chinese Academy of Agricultural Sciences, Harbin 150059, China
| | - Chaonan Liu
- the College of Veterinary Medicine, Northeast Agricultural University, Harbin 150030, China
| | - Shimin Zheng
- the College of Veterinary Medicine, Northeast Agricultural University, Harbin 150030, China
| | - Shi-Hua Xiang
- the Nebraska Center for Virology and School of Veterinary Medicine and Biomedical Sciences, University of Nebraska, Lincoln, Nebraska 68583, and
| | - Yong-Hui Zheng
- From the Harbin Veterinary Research Institute, CAAS-Michigan State University Joint Laboratory of Innate Immunity, State Key Laboratory of Veterinary Biotechnology, Chinese Academy of Agricultural Sciences, Harbin 150059, China, .,the Department of Microbiology and Molecular Genetics, Michigan State University, East Lansing, Michigan 48824
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8
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Exclusive Decoration of Simian Immunodeficiency Virus Env with High-Mannose Type N-Glycans Is Not Compatible with Mucosal Transmission in Rhesus Macaques. J Virol 2015; 89:11727-33. [PMID: 26355090 PMCID: PMC4645679 DOI: 10.1128/jvi.01358-15] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2015] [Accepted: 09/02/2015] [Indexed: 11/22/2022] Open
Abstract
Human immunodeficiency virus (HIV) and simian immunodeficiency virus (SIV) envelope (Env) proteins are extensively decorated with N-glycans, predominantly of the high-mannose type. However, it is unclear how high-mannose N-glycans on Env impact viral spread. We show that exclusive modification of SIV Env with these N-glycans reduces viral infectivity and abrogates mucosal transmission, despite increasing viral capture by immune cell lectins. Thus, high-mannose N-glycans have opposed effects on SIV infectivity and lectin reactivity, and a balance might be required for efficient mucosal transmission.
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9
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Reynolds MR, Piaskowski SM, Weisgrau KL, Weiler AM, Friedrich TC, Rakasz EG. Ex vivo analysis of SIV-infected cells by flow cytometry. Cytometry A 2011; 77:1059-66. [PMID: 20722008 DOI: 10.1002/cyto.a.20960] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Deciphering the complex interactions between human and simian immunodeficiency viruses (HIV/SIV) and their host cells is crucial to the development of improved therapies and vaccines. Investigating these relationships has been complicated by the inability to directly analyze infected cells among freshly isolated peripheral blood lymphocytes. Here, we describe a method to detect cells productively infected with SIVmac239 ex vivo from the blood or lymph nodes by flow cytometry. Using this method, we show a close correlation between the frequency of productively infected cells in both sample type and the plasma viral load. We define that the minimum threshold for detecting productively infected cells in lymph nodes by flow cytometry requires a plasma virus concentration of ∼2.5 × 10(4) vRNA copy Equivalents (Eq)/ml. Conversely, an approximately 2 logs higher plasma viral load is needed to detect productively infected cells in the peripheral blood. This novel protocol provides a direct analytical tool to assess interactions between SIV and host cells, which is of key importance to investigators in AIDS research.
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Affiliation(s)
- Matthew R Reynolds
- AIDS Vaccine Research Laboratory, University of Wisconsin-Madison, Madison, Wisconsin 53711, USA
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10
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Fitness disadvantage of transitional intermediates contributes to dynamic change in the infecting-virus population during coreceptor switch in R5 simian/human immunodeficiency virus-infected macaques. J Virol 2010; 84:12862-71. [PMID: 20943985 DOI: 10.1128/jvi.01478-10] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Fitness disadvantage of the transitional intermediates compared to the initial R5 viruses has been suggested to constitute one of the blockades to coreceptor switching, explaining the late appearance of X4 viruses. Using a simian model for human immunodeficiency virus type 1 (HIV-1) coreceptor switching, we demonstrate in this study that similar molecular evolutionary pathways to coreceptor switch occur in more than one R5 simian/human immunodeficiency virus (SHIV)(SF162P3N)-infected macaque. In infected animals where multiple pathways for expansion or switch to CXCR4 coexist, fitness of the transitional intermediates in coreceptor usage efficiency influences their outgrowth and representation in the infecting virus population. Dualtropic and X4 viruses appear at different disease stages, but they have lower entry efficiency than the coexisting R5 strains, which may explain why they do not outcompete the R5 viruses. Similar observations were made in two infected macaques with coreceptor switch, providing in vivo evidence that fitness disadvantage is an obstacle to X4 emergence and expansion.
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11
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Gag- and Nef-specific CD4+ T cells recognize and inhibit SIV replication in infected macrophages early after infection. Proc Natl Acad Sci U S A 2009; 106:9791-6. [PMID: 19478057 DOI: 10.1073/pnas.0813106106] [Citation(s) in RCA: 84] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The precise immunological role played by CD4(+) T cells in retroviral infections is poorly defined. Here, we describe a new function of these cells, the elimination of retrovirus-infected macrophages. After experimental CD8(+) cell depletion, elite controlling macaques with set-point viral loads < or = 500 viral RNA copies/mL mounted robust Gag- and Nef-specific CD4(+) T cell responses during reestablishment of control with > or = 54% of all virus-specific CD4(+) T cells targeting these 2 proteins. Ex vivo, these simian immunodeficiency virus (SIV)-specific CD4(+) T cells neither recognized nor suppressed viral replication in SIV-infected CD4(+) T cells. In contrast, they recognized SIV-infected macrophages as early as 2 h postinfection because of presentation of epitopes derived from virion-associated Gag and Nef proteins. Furthermore, virus-specific CD4(+) T cells displayed direct effector function and eliminated SIV-infected macrophages. These results suggest that retrovirus-specific CD4(+) T cells may contribute directly to elite control by inhibiting viral replication in macrophages.
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12
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HIV-1 and microvesicles from T cells share a common glycome, arguing for a common origin. Nat Chem Biol 2009; 5:244-50. [PMID: 19234452 PMCID: PMC2713040 DOI: 10.1038/nchembio.151] [Citation(s) in RCA: 134] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2008] [Accepted: 02/03/2009] [Indexed: 01/17/2023]
Abstract
HIV-1 is a master at deceiving the immune system, usurping host biosynthetic machinery. Although HIV-1 is coated with host-derived glycoproteins only glycosylation of viral gp120 has been described. Herein we utilize lectin microarray technology to analyze the glycome of intact HIV-1 virions. We show that the glycan coat of human T-cell line-derived HIV-1 matches that of native immunomodulatory microvesicles. The carbohydrate composition of both virus and microvesicles is cell-line dependent, suggesting a mechanism to rapidly camouflage the virus within the host. In addition, binding of both virus and microvesicles to antiviral lectins is enriched over the host cell, raising concern about targeting these glycans for therapeutics. This work also sheds light on the binding of HIV-1 to galectin-1, an important human immune lectin. Overall, our work strongly supports the theory that HIV-1 co-opts the exocytic pathway of microvesicles, potentially explaining why eliciting a protective antiviral immune response is difficult.
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13
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Abstract
With the increased survival of human immunodeficiency virus (HIV)-infected individuals resulting from therapy, disorders in other target organs of the virus, such as the brain, are becoming more prevalent. Here the author reviews his laboratory's work on the simian immunodeficiency virus (SIV)/nonhuman model of acquired immunodeficiency syndrome (AIDS), which has revealed unique characteristics of both the virus that infects the brain, and the innate and adaptive immune response within the central nervous system (CNS) to infection. Similar to findings in humans, neurocognitive/neurobehavioral disorders during the chronic phase of infection can be detected in monkeys, and recent findings reveal potential mechanisms of CNS damage due to the virus-host interaction.
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Affiliation(s)
- Howard S Fox
- Molecular and Integrative Neurosciences Department, The Scripps Research Institute, La Jolla, California 92037, USA.
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