1
|
Collins DR, Hitschfel J, Urbach JM, Mylvaganam GH, Ly NL, Arshad U, Racenet ZJ, Yanez AG, Diefenbach TJ, Walker BD. Cytolytic CD8 + T cells infiltrate germinal centers to limit ongoing HIV replication in spontaneous controller lymph nodes. Sci Immunol 2023; 8:eade5872. [PMID: 37205767 DOI: 10.1126/sciimmunol.ade5872] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2022] [Accepted: 04/26/2023] [Indexed: 05/21/2023]
Abstract
Follicular CD8+ T cells (fCD8) mediate surveillance in lymph node (LN) germinal centers against lymphotropic infections and cancers, but the precise mechanisms by which these cells mediate immune control remain incompletely resolved. To address this, we investigated functionality, clonotypic compartmentalization, spatial localization, phenotypic characteristics, and transcriptional profiles of LN-resident virus-specific CD8+ T cells in persons who control HIV without medications. Antigen-induced proliferative and cytolytic potential consistently distinguished spontaneous controllers from noncontrollers. T cell receptor analysis revealed complete clonotypic overlap between peripheral and LN-resident HIV-specific CD8+ T cells. Transcriptional analysis of LN CD8+ T cells revealed gene signatures of inflammatory chemotaxis and antigen-induced effector function. In HIV controllers, the cytotoxic effectors perforin and granzyme B were elevated among virus-specific CXCR5+ fCD8s proximate to foci of HIV RNA within germinal centers. These results provide evidence consistent with cytolytic control of lymphotropic infection supported by inflammatory recruitment, antigen-specific proliferation, and cytotoxicity of fCD8s.
Collapse
Affiliation(s)
- David R Collins
- Ragon Institute of MGH, MIT, and Harvard, Cambridge, MA, USA
- Howard Hughes Medical Institute, Chevy Chase, MD, USA
| | - Julia Hitschfel
- Ragon Institute of MGH, MIT, and Harvard, Cambridge, MA, USA
- Institute of Clinical and Molecular Virology, Friedrich-Alexander Universität Erlangen-Nürnberg, Erlangen, Germany
| | | | - Geetha H Mylvaganam
- Ragon Institute of MGH, MIT, and Harvard, Cambridge, MA, USA
- Howard Hughes Medical Institute, Chevy Chase, MD, USA
| | - Ngoc L Ly
- Ragon Institute of MGH, MIT, and Harvard, Cambridge, MA, USA
| | - Umar Arshad
- Ragon Institute of MGH, MIT, and Harvard, Cambridge, MA, USA
| | | | - Adrienne G Yanez
- Ragon Institute of MGH, MIT, and Harvard, Cambridge, MA, USA
- Howard Hughes Medical Institute, Chevy Chase, MD, USA
| | | | - Bruce D Walker
- Ragon Institute of MGH, MIT, and Harvard, Cambridge, MA, USA
- Howard Hughes Medical Institute, Chevy Chase, MD, USA
- Institute for Medical Engineering and Sciences and Department of Biology, Massachusetts Institute of Technology, Cambridge, MA, USA
| |
Collapse
|
2
|
Dias J, Fabozzi G, March K, Asokan M, Almasri CG, Fintzi J, Promsote W, Nishimura Y, Todd JP, Lifson JD, Martin MA, Gama L, Petrovas C, Pegu A, Mascola JR, Koup RA. Concordance of immunological events between intrarectal and intravenous SHIVAD8-EO infection when assessed by Fiebig-equivalent staging. J Clin Invest 2021; 131:e151632. [PMID: 34623326 PMCID: PMC8409578 DOI: 10.1172/jci151632] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2021] [Accepted: 07/22/2021] [Indexed: 11/17/2022] Open
Abstract
Primary HIV-1 infection can be classified into six Fiebig stages based on virological and serological laboratory testing, whereas simian-HIV (SHIV) infection in nonhuman primates (NHPs) is defined in time post-infection, making it difficult to extrapolate NHP experiments to the clinics. We identified and extensively characterized the Fiebig-equivalent stages in NHPs challenged intrarectally or intravenously with SHIVAD8-EO. During the first month post-challenge, intrarectally challenged monkeys were up to 1 week delayed in progression through stages. However, regardless of the challenge route, stages I-II predominated before, and stages V-VI predominated after, peak viremia. Decrease in lymph node (LN) CD4+ T cell frequency and rise in CD8+ T cells occurred at stage V. LN virus-specific CD8+ T cell responses, dominated by degranulation and TNF, were first detected at stage V and increased at stage VI. A similar late elevation in follicular CXCR5+ CD8+ T cells occurred, consistent with higher plasma CXCL13 levels at these stages. LN SHIVAD8-EO RNA+ cells were present at stage II, but appeared to decline at stage VI when virions accumulated in follicles. Fiebig-equivalent staging of SHIVAD8-EO infection revealed concordance of immunological events between intrarectal and intravenous infection despite different infection progressions, and can inform comparisons of NHP studies with clinical data.
Collapse
Affiliation(s)
- Joana Dias
- Immunology Laboratory, Vaccine Research Center
| | | | - Kylie March
- Tissue Analysis Core, Vaccine Research Center
| | | | | | | | | | | | - John-Paul Todd
- Translational Research Program, Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | - Jeffrey D. Lifson
- AIDS and Cancer Virus Program, Leidos Biomedical Research Inc., Frederick National Laboratory for Cancer Research, Frederick, Maryland, USA
| | | | - Lucio Gama
- Immunology Laboratory, Vaccine Research Center
| | | | | | | | | |
Collapse
|
3
|
Ferrando-Martinez S, Moysi E, Pegu A, Andrews S, Nganou Makamdop K, Ambrozak D, McDermott AB, Palesch D, Paiardini M, Pavlakis GN, Brenchley JM, Douek D, Mascola JR, Petrovas C, Koup RA. Accumulation of follicular CD8+ T cells in pathogenic SIV infection. J Clin Invest 2018; 128:2089-2103. [PMID: 29664020 DOI: 10.1172/jci96207] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2017] [Accepted: 03/06/2018] [Indexed: 01/06/2023] Open
Abstract
LN follicles constitute major reservoir sites for HIV/SIV persistence. Cure strategies could benefit from the characterization of CD8+ T cells able to access and eliminate HIV-infected cells from these areas. In this study, we provide a comprehensive analysis of the phenotype, frequency, localization, and functionality of follicular CD8+ T cells (fCD8+) in SIV-infected nonhuman primates. Although disorganization of follicles was a major factor, significant accumulation of fCD8+ cells during chronic SIV infection was also observed in intact follicles, but only in pathogenic SIV infection. In line with this, tissue inflammatory mediators were strongly associated with the accumulation of fCD8+ cells, pointing to tissue inflammation as a major factor in this process. These fCD8+ cells have cytolytic potential and can be redirected to target and kill HIV-infected cells using bispecific antibodies. Altogether, our data support the use of SIV infection to better understand the dynamics of fCD8+ cells and to develop bispecific antibodies as a strategy for virus eradication.
Collapse
Affiliation(s)
| | | | | | | | - Krystelle Nganou Makamdop
- Human Immunology Section, Vaccine Research Center (VRC), National Institute of Allergy and Infectious Diseases (NIAID), NIH, Bethesda, Maryland, USA
| | | | | | - David Palesch
- Department of Pathology, Emory University School of Medicine and Yerkes National Primate Research Center, Atlanta, Georgia, USA
| | - Mirko Paiardini
- Department of Pathology, Emory University School of Medicine and Yerkes National Primate Research Center, Atlanta, Georgia, USA
| | - George N Pavlakis
- Human Retrovirus Section, Center for Cancer Research, National Cancer Institute (NCI), Frederick, Maryland, USA
| | - Jason M Brenchley
- Barrier Immunity Section, Laboratory of Parasitic Diseases, NIAID, NIH, Bethesda, Maryland, USA
| | - Daniel Douek
- Human Immunology Section, Vaccine Research Center (VRC), National Institute of Allergy and Infectious Diseases (NIAID), NIH, Bethesda, Maryland, USA
| | | | | | | |
Collapse
|
4
|
Perdomo-Celis F, Taborda NA, Rugeles MT. Follicular CD8 + T Cells: Origin, Function and Importance during HIV Infection. Front Immunol 2017; 8:1241. [PMID: 29085360 PMCID: PMC5649150 DOI: 10.3389/fimmu.2017.01241] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2017] [Accepted: 09/19/2017] [Indexed: 12/14/2022] Open
Abstract
The lymphoid follicle is critical for the development of humoral immune responses. Cell circulation to this site is highly regulated by the differential expression of chemokine receptors. This feature contributes to the establishment of viral reservoirs in lymphoid follicles and the development of some types of malignancies that are able to evade immune surveillance, especially conventional CD8+ T cells. Interestingly, a subtype of CD8+ T cells located within the lymphoid follicle (follicular CD8+ T cells) was recently described; these cells have been proposed to play an important role in viral and tumor control, as well as to modulate humoral and T follicular helper cell responses. In this review, we summarize the knowledge on this novel CD8+ T cell population, its origin, function, and potential role in health and disease, in particular, in the context of the infection by the human immunodeficiency virus.
Collapse
Affiliation(s)
- Federico Perdomo-Celis
- Grupo Inmunovirología, Facultad de Medicina, Universidad de Antioquia (UdeA), Medellín, Colombia
| | - Natalia Andrea Taborda
- Grupo Inmunovirología, Facultad de Medicina, Universidad de Antioquia (UdeA), Medellín, Colombia.,Grupo de Investigaciones Biomédicas Uniremington, Programa de Medicina, Facultad de Ciencias de la Salud, Corporación Universitaria Remington, Medellín, Colombia
| | - María Teresa Rugeles
- Grupo Inmunovirología, Facultad de Medicina, Universidad de Antioquia (UdeA), Medellín, Colombia
| |
Collapse
|
5
|
Xu Y, Phetsouphanh C, Suzuki K, Aggrawal A, Graff-Dubois S, Roche M, Bailey M, Alcantara S, Cashin K, Sivasubramaniam R, Koelsch KK, Autran B, Harvey R, Gorry PR, Moris A, Cooper DA, Turville S, Kent SJ, Kelleher AD, Zaunders J. HIV-1 and SIV Predominantly Use CCR5 Expressed on a Precursor Population to Establish Infection in T Follicular Helper Cells. Front Immunol 2017; 8:376. [PMID: 28484447 PMCID: PMC5399036 DOI: 10.3389/fimmu.2017.00376] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2016] [Accepted: 03/15/2017] [Indexed: 01/28/2023] Open
Abstract
Background T follicular helper (Tfh) cells are increasingly recognized as a major reservoir of HIV infection that will likely need to be addressed in approaches to curing HIV. However, Tfh express minimal CCR5, the major coreceptor for HIV-1, and the mechanism by which they are infected is unclear. We have previously shown that macaque Tfh lack CCR5, but are infected in vivo with CCR5-using SIV at levels comparable to other memory CD4+ T cells. Similarly, human splenic Tfh cells are highly infected with HIV-1 DNA. Therefore, we set out to examine the mechanism of infection of Tfh cells. Methodology Tfh and other CD4+ T cell subsets from macaque lymph nodes and spleens, splenic Tfh from HIV+ subjects, and tonsillar Tfh from HIV-uninfected subjects were isolated by cell sorting prior to cell surface and molecular characterization. HIV proviral gp120 sequences were submitted to genotypic and phenotypic tropism assays. Entry of CCR5- and CXCR4-using viruses into Tfh from uninfected tonsillar tissue was measured using a fusion assay. Results Phylogenetic analysis, genotypic, and phenotypic analysis showed that splenic Tfh cells from chronic HIV+ subjects were predominantly infected with CCR5-using viruses. In macaques, purified CCR5+PD-1intermediate(int)+ memory CD4+ T cells were shown to include pre-Tfh cells capable of differentiating in vitro to Tfh by upregulation of PD-1 and Bcl6, confirmed by qRT-PCR and single-cell multiplex PCR. Infected PD-1int cells survive, carry SIV provirus, and differentiate into PD-1hi Tfh after T cell receptor stimulation, suggesting a pathway for SIV infection of Tfh. In addition, a small subset of macaque and human PD-1hi Tfh can express low levels of CCR5, which makes them susceptible to infection. Fusion assays demonstrated CCR5-using HIV-1 entry into CCR5+ Tfh and pre-Tfh cells from human tonsils. Conclusion The major route of infection of Tfh in macaques and humans appears to be via a CCR5-expressing pre-Tfh population. As the generation of Tfh are important for establishing effective immune responses during primary infections, Tfh are likely to be an early target of HIV-1 following transmission, creating an important component of the reservoir that has the potential to expand over time.
Collapse
Affiliation(s)
- Yin Xu
- The Kirby Institute, The University of New South Wales, Sydney, NSW, Australia
| | | | - Kazuo Suzuki
- The Kirby Institute, The University of New South Wales, Sydney, NSW, Australia.,St Vincent's Centre for Applied Medical Research, St Vincent's Hospital, Sydney, NSW, Australia
| | - Anu Aggrawal
- The Kirby Institute, The University of New South Wales, Sydney, NSW, Australia
| | - Stephanie Graff-Dubois
- Sorbonne Universités, UPMC Univ Paris 06, INSERM U1135, CNRS ERL 8255, Center for Immunology and Microbial Infections - CIMI-Paris, Paris, France
| | - Michael Roche
- Department of Microbiology and Immunology, Peter Doherty Institute, University of Melbourne, Melbourne, VIC, Australia.,Center for Biomedical Research, Burnet Institute, Melbourne, VIC, Australia
| | - Michelle Bailey
- The Kirby Institute, The University of New South Wales, Sydney, NSW, Australia
| | - Sheilajen Alcantara
- Department of Microbiology and Immunology, Peter Doherty Institute, University of Melbourne, Melbourne, VIC, Australia
| | - Kieran Cashin
- Center for Biomedical Research, Burnet Institute, Melbourne, VIC, Australia
| | - Rahuram Sivasubramaniam
- St Vincent's Centre for Applied Medical Research, St Vincent's Hospital, Sydney, NSW, Australia
| | - Kersten K Koelsch
- The Kirby Institute, The University of New South Wales, Sydney, NSW, Australia
| | - Brigitte Autran
- Sorbonne Universités, UPMC University Paris 06, INSERM U1135, Center for Immunology and Microbial Infections - CIMI-Paris, Paris, France.,AP-HP, Hôpital Pitié-Salpêtière, Department of Immunology, Paris, France
| | - Richard Harvey
- St Vincent's Centre for Applied Medical Research, St Vincent's Hospital, Sydney, NSW, Australia
| | - Paul R Gorry
- Center for Biomedical Research, Burnet Institute, Melbourne, VIC, Australia.,School of Health and Biomedical Sciences, College of Science, Engineering and Health, RMIT University, Bundoora, VIC, Australia
| | - Arnaud Moris
- Sorbonne Universités, UPMC Univ Paris 06, INSERM U1135, CNRS ERL 8255, Center for Immunology and Microbial Infections - CIMI-Paris, Paris, France.,AP-HP, Hôpital Pitié-Salpêtière, Department of Immunology, Paris, France
| | - David A Cooper
- The Kirby Institute, The University of New South Wales, Sydney, NSW, Australia.,St Vincent's Centre for Applied Medical Research, St Vincent's Hospital, Sydney, NSW, Australia
| | - Stuart Turville
- The Kirby Institute, The University of New South Wales, Sydney, NSW, Australia
| | - Stephen J Kent
- Department of Microbiology and Immunology, Peter Doherty Institute, University of Melbourne, Melbourne, VIC, Australia.,Department of Infectious Diseases, Alfred Hospital, Monash University, Melbourne, VIC, Australia
| | - Anthony D Kelleher
- The Kirby Institute, The University of New South Wales, Sydney, NSW, Australia.,St Vincent's Centre for Applied Medical Research, St Vincent's Hospital, Sydney, NSW, Australia
| | - John Zaunders
- The Kirby Institute, The University of New South Wales, Sydney, NSW, Australia.,St Vincent's Centre for Applied Medical Research, St Vincent's Hospital, Sydney, NSW, Australia
| |
Collapse
|
6
|
Petrovas C, Ferrando-Martinez S, Gerner MY, Casazza JP, Pegu A, Deleage C, Cooper A, Hataye J, Andrews S, Ambrozak D, Del Río Estrada PM, Boritz E, Paris R, Moysi E, Boswell KL, Ruiz-Mateos E, Vagios I, Leal M, Ablanedo-Terrazas Y, Rivero A, Gonzalez-Hernandez LA, McDermott AB, Moir S, Reyes-Terán G, Docobo F, Pantaleo G, Douek DC, Betts MR, Estes JD, Germain RN, Mascola JR, Koup RA. Follicular CD8 T cells accumulate in HIV infection and can kill infected cells in vitro via bispecific antibodies. Sci Transl Med 2017; 9:eaag2285. [PMID: 28100833 PMCID: PMC5497679 DOI: 10.1126/scitranslmed.aag2285] [Citation(s) in RCA: 121] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2016] [Accepted: 12/22/2016] [Indexed: 12/12/2022]
Abstract
Cytolytic CD8 T cells play a crucial role in the control and elimination of virus-infected cells and are a major focus of HIV cure efforts. However, it has been shown that HIV-specific CD8 T cells are infrequently found within germinal centers (GCs), a predominant site of active and latent HIV infection. We demonstrate that HIV infection induces marked changes in the phenotype, frequency, and localization of CD8 T cells within the lymph node (LN). Significantly increased frequencies of CD8 T cells in the B cell follicles and GCs were found in LNs from treated and untreated HIV-infected individuals. This profile was associated with persistent local immune activation but did not appear to be directly related to local viral replication. Follicular CD8 (fCD8) T cells, despite compromised cytokine polyfunctionality, showed good cytolytic potential characterized by high ex vivo expression of granzyme B and perforin. We used an anti-HIV/anti-CD3 bispecific antibody in a redirected killing assay and found that fCD8 T cells had better killing activity than did non-fCD8 T cells. Our results indicate that CD8 T cells with potent cytolytic activity are recruited to GCs during HIV infection and, if appropriately redirected to kill HIV-infected cells, could be an effective component of an HIV cure strategy.
Collapse
Affiliation(s)
- Constantinos Petrovas
- Immunology Laboratory, Vaccine Research Center, National Institute of Allergy and Infectious Diseases (NIAID), National Institutes of Health (NIH), Bethesda, MD 20892, USA.
| | - Sara Ferrando-Martinez
- Immunology Laboratory, Vaccine Research Center, National Institute of Allergy and Infectious Diseases (NIAID), National Institutes of Health (NIH), Bethesda, MD 20892, USA
| | - Michael Y Gerner
- Laboratory of Systems Biology, Lymphocyte Biology Section, NIAID, NIH, Bethesda, MD 20892, USA
| | - Joseph P Casazza
- Immunology Laboratory, Vaccine Research Center, National Institute of Allergy and Infectious Diseases (NIAID), National Institutes of Health (NIH), Bethesda, MD 20892, USA
| | - Amarendra Pegu
- Virology Laboratory, Vaccine Research Center, NIAID, NIH, Bethesda, MD 20892, USA
| | - Claire Deleage
- AIDS and Cancer Virus Program, Leidos Biomedical Research Inc., Frederick National Laboratory for Cancer Research, BG 535, Post Office Box B, Frederick, MD 21702, USA
| | - Arik Cooper
- Virology Laboratory, Vaccine Research Center, NIAID, NIH, Bethesda, MD 20892, USA
| | - Jason Hataye
- Immunology Laboratory, Vaccine Research Center, National Institute of Allergy and Infectious Diseases (NIAID), National Institutes of Health (NIH), Bethesda, MD 20892, USA
| | - Sarah Andrews
- Immunology Core Section, Vaccine Research Center, NIAID, NIH, Bethesda, MD 20892, USA
| | - David Ambrozak
- Immunology Laboratory, Vaccine Research Center, National Institute of Allergy and Infectious Diseases (NIAID), National Institutes of Health (NIH), Bethesda, MD 20892, USA
| | - Perla M Del Río Estrada
- Departamento de Investigación en Enfermedades Infecciosas, Instituto Nacional de Enfermedades Respiratorias, Mexico City, Mexico
| | - Eli Boritz
- Human Immunology Section, Vaccine Research Center, NIAID, NIH, Bethesda, MD 20892, USA
| | - Robert Paris
- Walter Reed Army Institute of Research, Silver Spring, MD 20910, USA
| | - Eirini Moysi
- Immunology Laboratory, Vaccine Research Center, National Institute of Allergy and Infectious Diseases (NIAID), National Institutes of Health (NIH), Bethesda, MD 20892, USA
| | - Kristin L Boswell
- Immunology Laboratory, Vaccine Research Center, National Institute of Allergy and Infectious Diseases (NIAID), National Institutes of Health (NIH), Bethesda, MD 20892, USA
| | - Ezequiel Ruiz-Mateos
- Laboratory of Immunovirology, Hospital Universitario Virgen del Rocío, Instituto de Biomedicina de Sevilla, Universidad de Sevilla, Consejo Superior de Investigaciones Cientificas, Sevilla 41013, Spain
| | - Ilias Vagios
- Department of Histopathology, Venizeleio Hospital, Iraklion, Crete, Greece
| | - Manuel Leal
- Laboratory of Immunovirology, Hospital Universitario Virgen del Rocío, Instituto de Biomedicina de Sevilla, Universidad de Sevilla, Consejo Superior de Investigaciones Cientificas, Sevilla 41013, Spain
| | - Yuria Ablanedo-Terrazas
- Departamento de Investigación en Enfermedades Infecciosas, Instituto Nacional de Enfermedades Respiratorias, Mexico City, Mexico
| | - Amaranta Rivero
- Departamento de Investigación en Enfermedades Infecciosas, Instituto Nacional de Enfermedades Respiratorias, Mexico City, Mexico
| | - Luz Alicia Gonzalez-Hernandez
- Departamento de Investigación en Enfermedades Infecciosas, Instituto Nacional de Enfermedades Respiratorias, Mexico City, Mexico
| | - Adrian B McDermott
- Immunology Core Section, Vaccine Research Center, NIAID, NIH, Bethesda, MD 20892, USA
| | - Susan Moir
- Laboratory of Immunoregulation, NIAID, NIH, Bethesda, MD 20892, USA
| | - Gustavo Reyes-Terán
- Departamento de Investigación en Enfermedades Infecciosas, Instituto Nacional de Enfermedades Respiratorias, Mexico City, Mexico
| | - Fernando Docobo
- Laboratory of Immunovirology, Hospital Universitario Virgen del Rocío, Instituto de Biomedicina de Sevilla, Universidad de Sevilla, Consejo Superior de Investigaciones Cientificas, Sevilla 41013, Spain
| | - Giuseppe Pantaleo
- Service of Immunology and Allergy, Service of Infectious Diseases, Department of Medicine and Swiss Vaccine Research Institute, Lausanne University Hospital, University of Lausanne, CH-1011 Lausanne, Switzerland
| | - Daniel C Douek
- Human Immunology Section, Vaccine Research Center, NIAID, NIH, Bethesda, MD 20892, USA
| | - Michael R Betts
- Department of Microbiology, Center for AIDS Research, and Institute for Immunology Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Jacob D Estes
- AIDS and Cancer Virus Program, Leidos Biomedical Research Inc., Frederick National Laboratory for Cancer Research, BG 535, Post Office Box B, Frederick, MD 21702, USA
| | - Ronald N Germain
- Laboratory of Systems Biology, Lymphocyte Biology Section, NIAID, NIH, Bethesda, MD 20892, USA
| | - John R Mascola
- Virology Laboratory, Vaccine Research Center, NIAID, NIH, Bethesda, MD 20892, USA
| | - Richard A Koup
- Immunology Laboratory, Vaccine Research Center, National Institute of Allergy and Infectious Diseases (NIAID), National Institutes of Health (NIH), Bethesda, MD 20892, USA
| |
Collapse
|
7
|
Lythgoe KA, Blanquart F, Pellis L, Fraser C. Large Variations in HIV-1 Viral Load Explained by Shifting-Mosaic Metapopulation Dynamics. PLoS Biol 2016; 14:e1002567. [PMID: 27706164 PMCID: PMC5051940 DOI: 10.1371/journal.pbio.1002567] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2016] [Accepted: 09/08/2016] [Indexed: 12/17/2022] Open
Abstract
The viral population of HIV-1, like many pathogens that cause systemic infection, is structured and differentiated within the body. The dynamics of cellular immune trafficking through the blood and within compartments of the body has also received wide attention. Despite these advances, mathematical models, which are widely used to interpret and predict viral and immune dynamics in infection, typically treat the infected host as a well-mixed homogeneous environment. Here, we present mathematical, analytical, and computational results that demonstrate that consideration of the spatial structure of the viral population within the host radically alters predictions of previous models. We study the dynamics of virus replication and cytotoxic T lymphocytes (CTLs) within a metapopulation of spatially segregated patches, representing T cell areas connected by circulating blood and lymph. The dynamics of the system depend critically on the interaction between CTLs and infected cells at the within-patch level. We show that for a wide range of parameters, the system admits an unexpected outcome called the shifting-mosaic steady state. In this state, the whole body’s viral population is stable over time, but the equilibrium results from an underlying, highly dynamic process of local infection and clearance within T-cell centers. Notably, and in contrast to previous models, this new model can explain the large differences in set-point viral load (SPVL) observed between patients and their distribution, as well as the relatively low proportion of cells infected at any one time, and alters the predicted determinants of viral load variation. A novel metapopulation model of HIV suggests that within-host infections are characterized by a highly dynamic process of localized infection followed by clearance within T cell centers. When a person is infected with HIV, the initial peak level of virus in the blood is usually very high before a lower, relatively stable level is reached and maintained for the duration of the chronic infection. This stable level is known as the set-point viral load (SPVL) and is associated with severity of infection. SPVL is also highly variable among patients, ranging from 100 to a million copies of the virus per mL of blood. The replicative capacity of the infecting virus and the strength of the immune response both influence SPVL. However, standard mathematical models show that variation in these two factors cannot easily reproduce the observed distribution of SPVL among patients. Standard models typically treat infected individuals as well-mixed systems, but in reality viral replication is localised in T-cell centres, or patches, found in secondary lymphoid tissue. To account for this population structure, we developed a carefully parameterised metapopulation model. We find the system can reach a steady state at which the viral load in the blood is relatively stable, representing SPVL, but surprisingly, the patches are highly dynamic, characterised by bursts of infection followed by elimination of virus due to localised host immune responses. Significantly, this model can reproduce the wide distribution of SPVLs found among infected individuals for realistic distributions of viral replicative capacity and strength of immune response. Our model can also be used in the future to understand other aspects of chronic HIV infection.
Collapse
Affiliation(s)
- Katrina A. Lythgoe
- Department of Zoology, Tinbergen Building, University of Oxford, Oxford, United Kingdom
- Department of Infectious Disease Epidemiology, School of Public Health, Imperial College London, St. Mary’s Campus, London, United Kingdom
- * E-mail:
| | - François Blanquart
- Department of Infectious Disease Epidemiology, School of Public Health, Imperial College London, St. Mary’s Campus, London, United Kingdom
| | - Lorenzo Pellis
- Mathematics Institute, Zeeman Building, University of Warwick, Coventry, United Kingdom
| | - Christophe Fraser
- Department of Infectious Disease Epidemiology, School of Public Health, Imperial College London, St. Mary’s Campus, London, United Kingdom
- Big Data Institute, Li Ka Shing Centre for Health Information and Discovery, Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom
| |
Collapse
|
8
|
Colineau L, Rouers A, Yamamoto T, Xu Y, Urrutia A, Pham HP, Cardinaud S, Samri A, Dorgham K, Coulon PG, Cheynier R, Hosmalin A, Oksenhendler E, Six A, Kelleher AD, Zaunders J, Koup RA, Autran B, Moris A, Graff-Dubois S. HIV-Infected Spleens Present Altered Follicular Helper T Cell (Tfh) Subsets and Skewed B Cell Maturation. PLoS One 2015; 10:e0140978. [PMID: 26501424 PMCID: PMC4621058 DOI: 10.1371/journal.pone.0140978] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2015] [Accepted: 09/16/2015] [Indexed: 12/27/2022] Open
Abstract
Follicular helper T (Tfh) cells within secondary lymphoid organs control multiple steps of B cell maturation and antibody (Ab) production. HIV-1 infection is associated with an altered B cell differentiation and Tfh isolated from lymph nodes of HIV-infected (HIV+) individuals provide inadequate B cell help in vitro. However, the mechanisms underlying this impairment of Tfh function are not fully defined. Using a unique collection of splenocytes, we compared the frequency, phenotype and transcriptome of Tfh subsets in spleens from HIV negative (HIV-) and HIV+ subjects. We observed an increase of CXCR5+PD-1highCD57-Tfh and germinal center (GC) CD57+ Tfh in HIV+ spleens. Both subsets showed a reduced mRNA expression of the transcription factor STAT-3, co-stimulatory, regulatory and signal transduction molecules as compared to HIV- spleens. Similarly, Foxp3 expressing follicular regulatory T (Tfr) cells were increased, suggesting sustained GC reactions in chronically HIV+ spleens. As a consequence, GC B cell populations were expanded, however, complete maturation into memory B cells was reduced in HIV+ spleens where we evidenced a compromised production of B cell-activating cytokines such as IL-4 and IL-10. Collectively our data indicate that, although Tfh proliferation and GC reactions seem to be ongoing in HIV-infected spleens, Tfh “differentiation” and expression of costimulatory molecules is skewed with a profound effect on B cell maturation.
Collapse
Affiliation(s)
- Lucie Colineau
- Sorbonne Universités, UPMC Université Paris 06, Center for Immunology and Microbial Infections—CIMI-Paris, Paris, France
- INSERM, U1135, Center for Immunology and Microbial Infections—CIMI-Paris, Paris, France
- CNRS, ERL 8255, Center for Immunology and Microbial Infections—CIMI-Paris, Paris, France
| | - Angeline Rouers
- Sorbonne Universités, UPMC Université Paris 06, Center for Immunology and Microbial Infections—CIMI-Paris, Paris, France
- INSERM, U1135, Center for Immunology and Microbial Infections—CIMI-Paris, Paris, France
- CNRS, ERL 8255, Center for Immunology and Microbial Infections—CIMI-Paris, Paris, France
| | - Takuya Yamamoto
- Immunology Laboratory, Vaccine research center, National Institute of Allergy and Infectious Diseases (NIAID), NIH, Bethesda, Maryland, United States of America
| | - Yin Xu
- The Kirby Institute for Infection and Immunity in Society, University of New South Wales, Sydney, Australia
| | - Alejandra Urrutia
- Sorbonne Universités, UPMC Université Paris 06, Center for Immunology and Microbial Infections—CIMI-Paris, Paris, France
- INSERM, U1135, Center for Immunology and Microbial Infections—CIMI-Paris, Paris, France
- CNRS, ERL 8255, Center for Immunology and Microbial Infections—CIMI-Paris, Paris, France
| | - Hang-Phuong Pham
- Sorbonne Universités UPMC Université Paris 06, UMRS 959, Immunology-Immunopathology-Immunotherapy (I3), Paris, France
- INSERM, UMRS 959, Immunology-Immunopathology-Immunotherapy (I3), Paris, France
- CNRS, FRE3632, Immunology-Immunopathology-Immunotherapy (I3), Paris, France
| | - Sylvain Cardinaud
- Sorbonne Universités, UPMC Université Paris 06, Center for Immunology and Microbial Infections—CIMI-Paris, Paris, France
- INSERM, U1135, Center for Immunology and Microbial Infections—CIMI-Paris, Paris, France
- CNRS, ERL 8255, Center for Immunology and Microbial Infections—CIMI-Paris, Paris, France
| | - Assia Samri
- Sorbonne Universités, UPMC Université Paris 06, Center for Immunology and Microbial Infections—CIMI-Paris, Paris, France
- INSERM, U1135, Center for Immunology and Microbial Infections—CIMI-Paris, Paris, France
- AP-HP, Hôpital Pitié-Salpêtière, Department of Immunology, Paris, France
| | - Karim Dorgham
- Sorbonne Universités, UPMC Université Paris 06, Center for Immunology and Microbial Infections—CIMI-Paris, Paris, France
- INSERM, U1135, Center for Immunology and Microbial Infections—CIMI-Paris, Paris, France
- AP-HP, Hôpital Pitié-Salpêtière, Department of Immunology, Paris, France
| | - Pierre-Grégoire Coulon
- Sorbonne Universités, UPMC Université Paris 06, Center for Immunology and Microbial Infections—CIMI-Paris, Paris, France
- INSERM, U1135, Center for Immunology and Microbial Infections—CIMI-Paris, Paris, France
- CNRS, ERL 8255, Center for Immunology and Microbial Infections—CIMI-Paris, Paris, France
| | - Rémi Cheynier
- INSERM, U1016, Institut Cochin, Paris, France
- CNRS, UMR8104, Paris, France
- Université Paris Descartes, Sorbonne Paris Cité, Paris, France
| | - Anne Hosmalin
- INSERM, U1016, Institut Cochin, Paris, France
- CNRS, UMR8104, Paris, France
- Université Paris Descartes, Sorbonne Paris Cité, Paris, France
- AP-HP, Hôpital Cochin, Paris, France
| | - Eric Oksenhendler
- Université Paris Diderot, Assistance Publique-Hôpitaux de Paris, Département d’Immunologie Clinique, Hôpital Saint-Louis, Paris, France
| | - Adrien Six
- Sorbonne Universités UPMC Université Paris 06, UMRS 959, Immunology-Immunopathology-Immunotherapy (I3), Paris, France
- INSERM, UMRS 959, Immunology-Immunopathology-Immunotherapy (I3), Paris, France
- CNRS, FRE3632, Immunology-Immunopathology-Immunotherapy (I3), Paris, France
| | - Anthony D. Kelleher
- The Kirby Institute for Infection and Immunity in Society, University of New South Wales, Sydney, Australia
| | - John Zaunders
- St. Vincent's Centre for Applied Medical Research, St. Vincent's Hospital, Sydney, Australia
| | - Richard A. Koup
- Immunology Laboratory, Vaccine research center, National Institute of Allergy and Infectious Diseases (NIAID), NIH, Bethesda, Maryland, United States of America
| | - Brigitte Autran
- Sorbonne Universités, UPMC Université Paris 06, Center for Immunology and Microbial Infections—CIMI-Paris, Paris, France
- INSERM, U1135, Center for Immunology and Microbial Infections—CIMI-Paris, Paris, France
- AP-HP, Hôpital Pitié-Salpêtière, Department of Immunology, Paris, France
| | - Arnaud Moris
- Sorbonne Universités, UPMC Université Paris 06, Center for Immunology and Microbial Infections—CIMI-Paris, Paris, France
- INSERM, U1135, Center for Immunology and Microbial Infections—CIMI-Paris, Paris, France
- CNRS, ERL 8255, Center for Immunology and Microbial Infections—CIMI-Paris, Paris, France
- AP-HP, Hôpital Pitié-Salpêtière, Department of Immunology, Paris, France
| | - Stéphanie Graff-Dubois
- Sorbonne Universités, UPMC Université Paris 06, Center for Immunology and Microbial Infections—CIMI-Paris, Paris, France
- INSERM, U1135, Center for Immunology and Microbial Infections—CIMI-Paris, Paris, France
- CNRS, ERL 8255, Center for Immunology and Microbial Infections—CIMI-Paris, Paris, France
- * E-mail:
| |
Collapse
|
9
|
Suspène R, Meyerhans A. Quantification of unintegrated HIV-1 DNA at the single cell level in vivo. PLoS One 2012; 7:e36246. [PMID: 22574142 PMCID: PMC3344866 DOI: 10.1371/journal.pone.0036246] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2012] [Accepted: 03/28/2012] [Indexed: 02/06/2023] Open
Abstract
In the nucleus of HIV-1 infected cells, unintegrated HIV-1 DNA molecules exist in the form of one and two LTR circles and linear molecules with degraded extremities. In tissue culture they are invariably more numerous than the provirus, the relative proportion of integrated to unintegrated forms varies widely from ∼1∶1 to 1∶10 and even over 1∶100. In vivo, this ratio is unknown. To determine it, single nuclei from two infected patients with a known provirus copy number were microdissected, HIV DNA was amplified by nested PCR, cloned and individual clones sequenced. Given the extraordinary sequence complexity, we made the assumption that the total number of distinct sequences approximated to real number of amplifiable HIV-1 DNA templates in the nucleus. We found that the number of unintegrated DNA molecules increased linearly with the proviral copy number there being on average 86 unintegrated molecules per provirus.
Collapse
Affiliation(s)
- Rodolphe Suspène
- Department of Virology, Institute of Medical Microbiology, University of the Saarland, Homburg/Saar, Germany.
| | | |
Collapse
|
10
|
Abstract
Tetraspanins are small integral membrane proteins that are known to control a variety of cellular processes, including signaling, migration and cell-cell fusion. Research over the past few years established that they are also regulators of various steps in the HIV-1 replication cycle, but the mechanisms through which these proteins either enhance or repress virus spread remain largely unknown.
Collapse
Affiliation(s)
- Markus Thali
- Department of Microbiology and Molecular Genetics, College of Medicine and CALS, University of Vermont, 318 Stafford Hall, 95 Carrigan Drive, Burlington, VT 05405-0084, USA.
| |
Collapse
|
11
|
Plasmacytoid dendritic cells accumulate in spleens from chronically HIV-infected patients but barely participate in interferon-α expression. Blood 2009; 113:6112-9. [DOI: 10.1182/blood-2008-07-170803] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
AbstractWe characterized the localization, phenotype, and some functions of plasmacytoid dendritic cells (pDCs) in the human spleen. pDCs were localized in the marginal zone and the periarteriolar region. Some were also found in the red pulp. pDCs were immature by phenotypic labeling, consistently with their capacity to internalize Dextran in a functional assay. In spleens from HIV-infected patients with thrombocytopenic purpura, these characteristics were unaffected. However, an accumulation of pDCs, but not myeloid dendritic cells (mDCs), was observed in some HIV+ patients, correlating with high proviral loads. Moreover, although undetectable in most HIV− patients, interferon-α (IFN-α) production was evidenced in situ and by flow cytometry in most HIV+ patients. IFN-α was located in the marginal zone. Surprisingly, IFN-α colocalized only with few pDCs, but rather with other cells, including T and B lymphocytes, mDCs, and macrophages. Therefore, pDCs accumulated in spleens from HIV+ patients with high proviral loads, but they did not seem to be the main IFN-α producers.
Collapse
|
12
|
van Grevenynghe J, Halwani R, Chomont N, Ancuta P, Peretz Y, Tanel A, Procopio FA, shi Y, Said EA, Haddad EK, Sekaly RP. Lymph node architecture collapse and consequent modulation of FOXO3a pathway on memory T- and B-cells during HIV infection. Semin Immunol 2008; 20:196-203. [PMID: 18757210 DOI: 10.1016/j.smim.2008.07.008] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/29/2008] [Accepted: 07/30/2008] [Indexed: 11/16/2022]
Abstract
Lymph nodes (LNs) represent the principal site where antigen-specific memory T- and B-cell responses are primed and differentiated into memory and effector cells. During chronic viral infections such as HIV, these lymphoid tissues undergo substantial structural changes. These changes are mostly caused by an imbalanced cytokine milieu, hyper-immune activation and collagen deposition leading to fibrotic LNs. The structural integrity of the LNs is essential to prime and maintain memory responses. Because cellular signalling events both up- and down-stream of FOXO3a are critical to the generation and the maintenance of lymphocyte memory, this review will focus on the interplay between the deregulation of the immune system caused by the virus and its impact on FOXO3a.
Collapse
Affiliation(s)
- Julien van Grevenynghe
- Laboratoire d'Immunologie, Centre de Recherche, Hôpital Saint-Luc, Centre Hospitalier de l'Université de Montréal, Montréal, Québec, Canada
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
13
|
O'Neill DW, Bhardwaj N. Armed and ready: how effector T cells deploy in reactive lymph nodes to modulate immunity. Nat Immunol 2007; 8:679-81. [PMID: 17579644 DOI: 10.1038/ni0707-679] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
|
14
|
Connick E, Mattila T, Folkvord JM, Schlichtemeier R, Meditz AL, Ray MG, McCarter MD, Mawhinney S, Hage A, White C, Skinner PJ. CTL fail to accumulate at sites of HIV-1 replication in lymphoid tissue. THE JOURNAL OF IMMUNOLOGY 2007; 178:6975-83. [PMID: 17513747 DOI: 10.4049/jimmunol.178.11.6975] [Citation(s) in RCA: 179] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The inability of HIV-1-specific CTL to fully suppress virus replication as well as the failure of administration of exogenous CTL to lower viral loads are not understood. To evaluate the hypothesis that these phenomena are due to a failure of CTL to localize at sites of HIV-1 replication, we assessed the distribution of HIV-1 RNA and HIV-1-specific CTL identified by HIV-1 peptide/HLA class I tetrameric complexes (tetramers) within lymph nodes of 14 HIV-1-infected individuals who were not receiving antiretroviral therapy. A median of 0.04% of follicular compared with 0.001% of extrafollicular CD4(+) cells were estimated to be producing HIV-1 RNA, a 40-fold difference (p = 0.0001). Tetramer-stained cells were detected by flow cytometry in disaggregated lymph node cells from 11 subjects and constituted a significantly higher fraction of CD8(+) cells in lymph node (mean, 2.15%) than in PBMC (mean, 1.52%; p = 0.02). In situ tetramer staining in three subjects' lymph nodes, in which high frequencies of tetramer-stained cells were detected, revealed that tetramer-stained cells were primarily concentrated in extrafollicular regions of lymph node and were largely absent within lymphoid follicles. These data confirm that HIV-1-specific CTL are abundant within lymphoid tissues, but fail to accumulate within lymphoid follicles where HIV-1 replication is concentrated, suggesting that lymphoid follicles may be immune-privileged sites. Mechanisms underlying the exclusion of CTL from lymphoid follicles as well as the role of lymphoid follicles in perpetuating other chronic pathogens merit further investigation.
Collapse
Affiliation(s)
- Elizabeth Connick
- Division of Infectious Diseases, University of Colorado at Denver and Health Sciences Center, Denver, CO 80262, USA.
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
15
|
Guarda G, Hons M, Soriano SF, Huang AY, Polley R, Martín-Fontecha A, Stein JV, Germain RN, Lanzavecchia A, Sallusto F. L-selectin-negative CCR7- effector and memory CD8+ T cells enter reactive lymph nodes and kill dendritic cells. Nat Immunol 2007; 8:743-52. [PMID: 17529983 DOI: 10.1038/ni1469] [Citation(s) in RCA: 165] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2007] [Accepted: 04/17/2007] [Indexed: 01/21/2023]
Abstract
T lymphocytes lacking the lymph node-homing receptors L-selectin and CCR7 do not migrate to lymph nodes in the steady state. Instead, we found here that lymph nodes draining sites of mature dendritic cells or adjuvant inoculation recruited L-selectin-negative CCR7- effector and memory CD8+ T cells. This recruitment required CXCR3 expression on T cells and occurred through high endothelial venules in concert with lumenal expression of the CXCR3 ligand CXCL9. In reactive lymph nodes, recruited T cells established stable interactions with and killed antigen-bearing dendritic cells, limiting the ability of these dendritic cells to activate naive CD4+ and CD8+ T cells. The inducible recruitment of blood-borne effector and memory T cells to lymph nodes may represent a mechanism for terminating primary and limiting secondary immune responses.
Collapse
Affiliation(s)
- Greta Guarda
- Institute for Research in Biomedicine, CH-6500 Bellinzona, Switzerland
| | | | | | | | | | | | | | | | | | | |
Collapse
|
16
|
Lemey P, Kosakovsky Pond SL, Drummond AJ, Pybus OG, Shapiro B, Barroso H, Taveira N, Rambaut A. Synonymous substitution rates predict HIV disease progression as a result of underlying replication dynamics. PLoS Comput Biol 2007; 3:e29. [PMID: 17305421 PMCID: PMC1797821 DOI: 10.1371/journal.pcbi.0030029] [Citation(s) in RCA: 142] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2006] [Accepted: 12/29/2006] [Indexed: 12/02/2022] Open
Abstract
Upon HIV transmission, some patients develop AIDS in only a few months, while others remain disease free for 20 or more years. This variation in the rate of disease progression is poorly understood and has been attributed to host genetics, host immune responses, co-infection, viral genetics, and adaptation. Here, we develop a new “relaxed-clock” phylogenetic method to estimate absolute rates of synonymous and nonsynonymous substitution through time. We identify an unexpected association between the synonymous substitution rate of HIV and disease progression parameters. Since immune activation is the major determinant of HIV disease progression, we propose that this process can also determine viral generation times, by creating favourable conditions for HIV replication. These conclusions may apply more generally to HIV evolution, since we also observed an overall low synonymous substitution rate for HIV-2, which is known to be less pathogenic than HIV-1 and capable of tempering the detrimental effects of immune activation. Humoral immune responses, on the other hand, are the major determinant of nonsynonymous rate changes through time in the envelope gene, and our relaxed-clock estimates support a decrease in selective pressure as a consequence of immune system collapse. During the clinical course of HIV infection, an asymptomatic phase always precedes the acquired immunodeficiency syndrome (AIDS). The duration of this asymptomatic phase is highly variable among patients and reflects the rate at which the immune system gradually deteriorates. Although humoral and cell-mediated immune responses are mounted against HIV, continuous replication and adaptation allows the virus to escape host immune responses. To gain a better understanding of the role of viral evolution in disease progression, we developed a new computational technique that can estimate changes in the absolute rates of synonymous and nonsynonymous divergence through time from molecular sequences. Using this type of evolutionary inference, we have identified a previously unknown association between the “silent” evolutionary rate of HIV and the rate of disease progression in infected individuals. This finding demonstrates that cellular immune processes, which are already known to determine HIV pathogenesis, also determine viral replication rates and therefore impose important constraints on HIV evolution.
Collapse
Affiliation(s)
- Philippe Lemey
- Department of Zoology, University of Oxford, Oxford, United Kingdom.
| | | | | | | | | | | | | | | |
Collapse
|
17
|
Petito CK, Torres-Muñoz JE, Zielger F, McCarthy M. Brain CD8+ and cytotoxic T lymphocytes are associated with, and may be specific for, human immunodeficiency virus type 1 encephalitis in patients with acquired immunodeficiency syndrome. J Neurovirol 2006; 12:272-83. [PMID: 16966218 DOI: 10.1080/13550280600879204] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
CD8+ T cells infiltrate brains with human immunodeficiency virus type-1 (HIV-1) encephalitis (HIVE) and related animal models; their perineuronal localization suggests cytotoxic T cell (CTL)-mediated neuronal killing. Because CTLs have not been identified in acquired immunodeficiency syndrome (AIDS) brains, the authors identified their cytotoxic granules in autopsy AIDS brains with HIVE and without HIVE (HIVnE) plus controls (7 to 13 cases/group) and determined gene expression profiles of CTL-associated genes in a separate series of cases. CD3+ and CD8+ T cells were significantly increased (P < .01) in perivascular spaces and inflammatory nodules in HIVE but were rare or absent in brain parenchyma in HIVnE and control brains. Eight HIVE brains contained granzyme B+ T cells and five contained perforin+ T cells. Their T-cell origin was confirmed by colocalization of CD8 and granzyme B in the same cell and the absence of CD56+ natural killer cells. The CTLs directly contacted with neurons, as the authors showed previously for CD3+ and CD8+ T cells. CTLs were rare or absent in HIV nonencephalitis (HIVnE) and controls. Granzyme B and H precursor gene expression was up-regulated and interleukin (IL)-12A precursor, a maturation factor for natural killer cells and CTLs, was down-regulated in HIVE versus HIVnE brain. This study demonstrates, for the first time, CTLs in HIVE and shows that parenchymal T cells and CTLs are sensitive biomarkers for HIVE. Consequently, CD8+ T cells and CTLs could mediate brain injury in HIVE and may represent an important biomarker for productive brain infection by HIV-1.
Collapse
Affiliation(s)
- Carol K Petito
- Department of Pathology, Miller School of Medicine, University of Miami, Miami, Florida 33136, USA.
| | | | | | | |
Collapse
|
18
|
Grossman Z, Meier-Schellersheim M, Paul WE, Picker LJ. Pathogenesis of HIV infection: what the virus spares is as important as what it destroys. Nat Med 2006; 12:289-95. [PMID: 16520776 DOI: 10.1038/nm1380] [Citation(s) in RCA: 304] [Impact Index Per Article: 16.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Upon transmission to a new host, HIV targets CCR5+ CD4+ effector memory T cells, resulting in acute, massive depletion of these cells from mucosal effector sites. This depletion does not initially compromise the regenerative capacity of the immune system because naive and most central memory T cells are spared. Here, we discuss evidence suggesting that frequent activation of these spared cells during the chronic phase of HIV infection supplies mucosal tissues with short-lived CCR5+ CD4+ effector cells that prevent life-threatening infections. This immune activation also facilitates continued viral replication, but infection and killing of target T cells by HIV are selective and the impact on effector-cell lifespan is limited. We propose, however, that persistent activation progressively disrupts the functional organization of the immune system, reducing its regenerative capacity and facilitating viral evolution that leads to loss of the exquisite target cell-sparing selectivity of viral replication, ultimately resulting in AIDS.
Collapse
Affiliation(s)
- Zvi Grossman
- Laboratory of Immunology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland 20892, USA.
| | | | | | | |
Collapse
|
19
|
Dumaurier MJ, Gratton S, Wain-Hobson S, Cheynier R. The majority of human immunodeficiency virus type 1 particles present within splenic germinal centres are produced locally. J Gen Virol 2005; 86:3369-3373. [PMID: 16298984 DOI: 10.1099/vir.0.81133-0] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
In most stages of human immunodeficiency virus (HIV) infection, cell-free viral particles can be detected in germinal centres (GCs) that are principally retained, in the form of immune complexes, on the surface of follicular dendritic cells (FDCs). The source of this virus remains unknown, although it is agreed that the FDCs themselves are not infected productively. By sequencing HIV viral DNA, genomic RNA and spliced mRNA isolated from individual splenic white pulps, it was shown here that the majority of HIV-1 viral particles are produced locally within the supporting lymphoid structure and do not result from trapping of circulating viruses or immune complexes. These findings underline the exquisite spatial organization of HIV-1 replication in vivo, suggesting a local origin for viruses trapped in splenic GCs.
Collapse
Affiliation(s)
| | - Sophie Gratton
- Unité de Rétrovirologie Moléculaire, Institut Pasteur, Paris, France
| | - Simon Wain-Hobson
- Unité de Rétrovirologie Moléculaire, Institut Pasteur, Paris, France
| | - Rémi Cheynier
- Unité de Rétrovirologie Moléculaire, Institut Pasteur, Paris, France
| |
Collapse
|
20
|
Renoux C, Wain-Hobson S, Hurtrel B, Cheynier R. Antigenic stimulation specifically reactivates the replication of archived simian immunodeficiency virus genomes in chronically infected macaques. J Virol 2005; 79:11231-8. [PMID: 16103175 PMCID: PMC1193569 DOI: 10.1128/jvi.79.17.11231-11238.2005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Human immunodeficiency virus/simian immunodeficiency virus (SIV) diversification is a direct consequence of viral replication and occurs principally in secondary lymphoid organs where CD4(+) T cells are activated and proliferate. However, the evolution of viral quasispecies may also be driven by various nonexclusive mechanisms, including adaptation to specific immune responses and modification of viral fitness. Analysis of viral quasispecies in SIV-infected macaques subjected to repeated antigenic stimulations allowed us to demonstrate transient expansions of SIV populations that were highly dependent upon activation of antigen-specific T cells. T-cell clones expanded in response to a particular antigen were infected by a specific viral population and persisted for prolonged periods. Upon a second stimulation by encounter with the same antigen, these specific genomes were at the origin of a new burst of replication, leading to rapid but transient replacement of the viral quasispecies in blood. Finally, longitudinal analysis of SIV sequence variation during and between antigenic stimulations revealed that viral evolution is mostly constrained to periods of strong immunological activity.
Collapse
Affiliation(s)
- Céline Renoux
- Unité de Rétrovirologie Moléculaire, Unité de Recherche et d'Expertise Physiopathologue des Infections Lentivirales, Paris, France
| | | | | | | |
Collapse
|
21
|
Bernardin F, Magierowska M, Dandekar S, Van Rompay KKA, Delwart EL. Number of CD4+ and CD8+ T-cell CDR3 clonotypes expanding during acute infection of macaques with simian immunodeficiency virus. Virology 2004; 322:105-17. [PMID: 15063121 DOI: 10.1016/j.virol.2004.01.022] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2003] [Revised: 01/05/2004] [Accepted: 01/20/2004] [Indexed: 10/26/2022]
Abstract
The total number of circulating CD4+ and CD8+ T-cells undergoing clonal expansions following SIV(mac251) infection was determined using a T-cell receptor Vbeta chain (TRBV) third complementarity-determining region (CDR3) DNA heteroduplex tracking assay (HTA). This assay measures the number of newly expanding T-cell clones but not their antigenic specificity. Fewer expanding CD4+ (3-23 per animal) than CD8+ (18-37 per animal) clonotypes were observed during the acute phase of SIV infection. CD8+ T-cell expansions peaked at 4 weeks postinfection (wpi) concomitant with early reductions in viremia. Expanding clone TRBV transcripts ranged in frequency from the limit of detection of 2% to 40% of their TRBV subfamily's transcripts. The number of expanding CD4+ or CD8+ clones correlated with neither peak, subsequent slope, nor steady-state viremia. CDR3 repertoires in CD8-expressing cells in different anatomical compartments were also analyzed. Repertoires were polyclonal in the thymus, oligoclonal in mesenteric lymph nodes, peripheral blood mononuclear cells (PBMC), and spleen, and extremely oligoclonal in intra-epithelial lymphocytes (IEL) and lamina propria lymphocytes (LPL). The lack of correlation between the number of expanding T-cell clonotypes and viremia levels may reflect the highly variable selection pressure imposed on SIV by T-cell responses targeting different epitopes in outbred macaques.
Collapse
|
22
|
Karlsson AC, Younger SR, Martin JN, Grossman Z, Sinclair E, Hunt PW, Hagos E, Nixon DF, Deeks SG. Immunologic and virologic evolution during periods of intermittent and persistent low-level viremia. AIDS 2004; 18:981-9. [PMID: 15096800 DOI: 10.1097/00002030-200404300-00005] [Citation(s) in RCA: 91] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
BACKGROUND HIV replication, HIV-specific T-cell responses and T-cell activation each contributes to disease outcome during untreated HIV infection. The interaction of these factors is not well understood, particularly in the setting of antiretroviral therapy. METHODS This is a longitudinal study of antiretroviral-treated patients with plasma HIV RNA levels < 1000 copies/ml. Patients were divided into three groups: suppressed viremia, intermittent viremia ('blips') and persistent low-level viremia. HIV-specific immunity was measured using interferon-gamma ELISPOT. T-cell activation was defined by CD38 and HLA-DR co-expression. Drug resistance was quantified using a phenotypic susceptibility assay. RESULTS The breadth and the magnitude of the HIV-specific CD8 T-cell response was greater in patients with either intermittent or persistent viremia compared to patients with suppressed viremia. In contrast, T-cell activation was significantly elevated only in those patients with persistent viremia. Patients with persistent low-level viremia had moderate levels of phenotypic antiretroviral drug resistance that increased over time. Virologic failure (confirmed increase in viral load > 1000 HIV RNA copies/ml) was primarily observed in the persistently viremic group. CONCLUSIONS Antiretroviral-treated individuals with intermittent viremia appear to mount an effective HIV-specific T-cell response while not experiencing increases in the level of immune activation. This may limit viral evolution and emergence of drug resistance. In contrast, antiretroviral-treated individuals with persistent low-level viremia exhibit significant increases in overall immune activation and a substantial risk of subsequent treatment failure. It is likely that higher viremia and stronger immune activation act synergistically to accelerate the development of systemic drug resistance.
Collapse
Affiliation(s)
- Annika C Karlsson
- Gladstone Institute of Virology and Immunology, University of California, San Francisco, USA
| | | | | | | | | | | | | | | | | |
Collapse
|
23
|
Iyengar S, Chin B, Margolick JB, Sabundayo BP, Schwartz DH. Anatomical loci of HIV-associated immune activation and association with viraemia. Lancet 2003; 362:945-50. [PMID: 14511927 DOI: 10.1016/s0140-6736(03)14363-2] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND Lymphocyte activation, associated with vaccination or infection, can be measured by positron emission tomography (PET). We investigated the ability of PET to detect and measure magnitude of lymph-node activation among asymptomatic HIV-1-infected individuals. METHODS Initially we assessed PET response in eight HIV-1-uninfected individuals who had received licensed killed influenza vaccine. In an urban teaching hospital, we recruited 12 patients recently infected with HIV-1 (<18 months since seroconversion) and 11 chronic long-term HIV-1 patients who had stable viraemia by RT-PCR (non-progressors). After injection with fluorine-18-labelled fluorodeoxyglucose, patients underwent PET. We correlated summed PET signal from nodes with viral load by linear regression on log-transformed values. FINDINGS Node activation was more localised after vaccination than after HIV-1 infection. In early and chronic HIV-1 disease, node activation was greater in cervical and axillary than in inguinal and iliac chains (p<0.0001), and summed PET signal correlated with viraemia across a 4 log range (r2=0.98, p<0.0001). Non-progressors had small numbers of persistently active nodes, most of which were surgically accessible. INTERPRETATION The anatomical restriction we noted may reflect microenvironmental niche selection, and tight correlation of PET signal with viraemia suggests target-cell activation determines steady-state viral replication.
Collapse
Affiliation(s)
- Sujatha Iyengar
- Bloomberg School of Public Health, Department of Molecular Microbiology and Immunology, Johns Hopkins University, Baltimore, MD 21205, USA
| | | | | | | | | |
Collapse
|
24
|
Chitnis V, Pahwa R, Pahwa S. Determinants of HIV-specific CD8 T-cell responses in HIV-infected pediatric patients and enhancement of HIV-gag-specific responses with exogenous IL-15. Clin Immunol 2003; 107:36-45. [PMID: 12738248 DOI: 10.1016/s1521-6616(02)00051-7] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Cellular immune responses play a central role in controlling HIV-1 infection. HIV-specific IFN-gamma production by CD8 T cells was evaluated in 17 HLA-A2+ HIV-infected pediatric patients (age range 1 month to 16 years) in an ELISPOT assay. Most patients (15/17) exhibited responses to HIV-gag, followed by responses to envelope gp120, gp41, and V3 loop. Only 7 patients responded to all four antigenic peptides. Treatment-related immune reconstitution of CD4 T cells was associated with increase in gag-specific responses, but these declined with prolonged viral suppression. Exogenous IL-15 resulted in augmentation of HIV-gag-specific response in 71% of patients, while IL-2 and IL-7 had variable effects, augmenting responses in 25% patients. Thus, HIV-specific CD8 T-cell responses are dependent on both CD4 T-cell help and antigenic stimulation. The cytokine IL-15 may be a useful modality as adjunctive therapy to augment HIV-specific memory CD8 T cells.
Collapse
Affiliation(s)
- Vivek Chitnis
- Immunology and Inflammation Center of Excellence, North Shore-Long Island Jewish Research Institute, Manhasset, NY 11030, USA
| | | | | |
Collapse
|
25
|
Andrieu M, Desoutter JF, Loing E, Gaston J, Hanau D, Guillet JG, Hosmalin A. Two human immunodeficiency virus vaccinal lipopeptides follow different cross-presentation pathways in human dendritic cells. J Virol 2003; 77:1564-70. [PMID: 12502869 PMCID: PMC140847 DOI: 10.1128/jvi.77.2.1564-1570.2003] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
An efficient vaccine against human immunodeficiency virus (HIV) must induce good cellular immune responses. To do this, it must be processed and presented by dendritic cells, which are required for primary T-lymphocyte stimulation. We have previously shown that a model lipopeptide containing a short epitopic peptide from HIV-1 was endocytosed and presented in association with major histocompatibility complex class I molecules by human dendritic cells to specific CD8(+) T lymphocytes, but the cross-presentation pathway needed to be precisely determined. We have studied a longer lipopeptide (Pol(461-484)) and another lipopeptide (Nef(66-97)) currently being used in vaccine trials. Like the shorter lipopeptide, the rhodamine-labeled Pol(461-484) lipopeptide was internalized by endocytosis, as assessed by confocal microscopy. The lipopeptides were processed by dendritic cells and presented to CD8(+) T cells specific for the HLA-A*0201-restricted Pol(476-484) and the HLA-A*0301-restricted Nef(73-82) epitope, respectively. Presentation of both lipopeptides was inhibited by brefeldin A. Presentation of the Pol lipopeptide was inhibited by epoxomycin, a proteasome-specific inhibitor, but not by monensin. This shows that it gained access to the cytosol to be digested by the proteasome. In contrast, presentation of the Nef lipopeptide was not inhibited by epoxomycin but was inhibited by monensin, a classical inhibitor of acid-dependent endosomal enzyme activity, indicating an endocytic processing pathway yielding to major histocompatibility complex class I-restricted presentation. Therefore, the two lipopeptides followed different cross-presentation pathways, both resulting in efficient presentation to CD8(+) T lymphocytes.
Collapse
Affiliation(s)
- Muriel Andrieu
- Département d'Immunologie, Unité INSERM 567, UMR CNRS 8104, IFR 116, Institut Cochin, Paris, France
| | | | | | | | | | | | | |
Collapse
|
26
|
Zhang L, Rowe L, He T, Chung C, Yu J, Yu W, Talal A, Markowitz M, Ho DD. Compartmentalization of surface envelope glycoprotein of human immunodeficiency virus type 1 during acute and chronic infection. J Virol 2002; 76:9465-73. [PMID: 12186928 PMCID: PMC136436 DOI: 10.1128/jvi.76.18.9465-9473.2002] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Human immunodeficiency virus type 1 is characterized by extensive genetic heterogeneity. Having previously demonstrated that, in the peripheral blood, the initial viral population is more homogeneous than at subsequent stages of infection, we have extended our studies to tissue samples, allowing comparisons between viral populations in peripheral blood and tissues during both the acute and chronic stages of infection. We found that homogeneity in gp120 sequences during the acute infection phase is not just restricted to the peripheral blood but also extends to other tissue compartments. However, in chronically infected individuals, heterogeneous and distinct viral populations were found in different compartments. We therefore conclude that the dominant and homogeneous viral population observed during the acute infection phase is likely to infiltrate lymphoid tissues and form the genetic bases for subsequent diversification. It is therefore likely that the compartmentalization of viral sequences observed in chronically infected patients reflects a gradual diversification of a common dominant viral variant rather than the preferential migration of distinct viral populations to different tissue compartments at the beginning of infection.
Collapse
Affiliation(s)
- Linqi Zhang
- Aaron Diamond AIDS Research Center, The Rockefeller University, New York, New York 10016, USA.
| | | | | | | | | | | | | | | | | |
Collapse
|
27
|
Heintel T, Sester M, Rodríguez MMB, Krieg C, Sester U, Wagner R, Pees HW, Gärtner B, Maier R, Meyerhans A. The fraction of perforin-expressing HIV-specific CD8 T cells is a marker for disease progression in HIV infection. AIDS 2002; 16:1497-501. [PMID: 12131187 DOI: 10.1097/00002030-200207260-00006] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVE Perforin is an important component of the death machinery of cytotoxic T cells (CTL). To evaluate functional differences between HIV- and cytomegalovirus (CMV)-specific CTL of coinfected patients, the frequencies of the respective perforin-expressing T cells were analysed in a rapid whole blood assay. METHODS Whole blood of HIV- and CMV-infected individuals was specifically stimulated by HIV-1 Pr55(gag) or complete CMV antigen, and activation-induced intracellular cytokine and perforin expression in CD8 T cells was analysed by flow cytometry. RESULTS Perforin-expressing HIV-1- and CMV-specific CD8 T cells can be quantified simultaneously. Within a patient, the frequency of such HIV-specific CD8 T cells in peripheral blood was lower than the frequency of the respective CMV-specific cells. The number of the perforin-expressing HIV-specific CD8 T cells inversely correlated with the peripheral blood CD4 T cell count. CONCLUSIONS The differential fractions of perforin-expressing virus-specific CD8 T cells in HIV and CMV double infection might be caused by differences in priming and trafficking to or from replication sites. However, without knowing the underlying mechanism, the fraction of perforin-expressing HIV-specific CD8 T cells provides another surrogate marker for disease progression.
Collapse
Affiliation(s)
- Tanja Heintel
- Department of Virology, Institute of Medical Microbiology and Hygiene, University of the Saarland, Homburg, Germany
| | | | | | | | | | | | | | | | | | | |
Collapse
|
28
|
Altfeld M, van Lunzen J, Frahm N, Yu XG, Schneider C, Eldridge RL, Feeney ME, Meyer-Olson D, Stellbrink HJ, Walker BD. Expansion of pre-existing, lymph node-localized CD8+ T cells during supervised treatment interruptions in chronic HIV-1 infection. J Clin Invest 2002. [DOI: 10.1172/jci0214789] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
|
29
|
Altfeld M, van Lunzen J, Frahm N, Yu XG, Schneider C, Eldridge RL, Feeney ME, Meyer-Olson D, Stellbrink HJ, Walker BD. Expansion of pre-existing, lymph node-localized CD8+ T cells during supervised treatment interruptions in chronic HIV-1 infection. J Clin Invest 2002; 109:837-43. [PMID: 11901192 PMCID: PMC150914 DOI: 10.1172/jci14789] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2001] [Accepted: 02/04/2002] [Indexed: 11/17/2022] Open
Abstract
To date, most studies have focused on the characterization of HIV-1-specific cellular immune responses in the peripheral blood (PB) of infected individuals. Much less is known about the comparative magnitude and breadth of responses in the lymphoid tissue. This study analyzed HIV-1-specific CD8+ T cell responses simultaneously in PB and lymph nodes (LNs) of persons with chronic HIV-1 infection and assessed the dynamics of these responses during antiretroviral treatment and supervised treatment interruption (STI). In untreated chronic infection, the magnitude of epitope-specific CD8+ T cell activity was significantly higher in LNs than in PB. Responses decreased in both compartments during highly active antiretroviral therapy, but this decline was more pronounced in PB. During STI, HIV-1-specific CD8+ T cell responses in PB increased significantly. Enhancement in breadth and magnitude was largely due to the expansion of pre-existing responses in the LNs, with new epitopes infrequently targeted. Taken together, these data demonstrate that HIV-1-specific CD8+ T cells are preferentially located in the LNs, with a subset of responses exclusively detectable in this compartment. Furthermore, the enhanced CD8+ T cell responses observed during STI in chronically infected individuals is largely due to expansion of pre-existing virus-specific CD8+ T cells, rather than the induction of novel responses.
Collapse
Affiliation(s)
- Marcus Altfeld
- Partners AIDS Research Center and Infectious Disease Division, Massachusetts General Hospital and Division of AIDS, Harvard Medical School, Boston, MA 02129, USA
| | | | | | | | | | | | | | | | | | | |
Collapse
|
30
|
Blancou P, Chenciner N, Cumont MC, Wain-Hobson S, Hurtrel B, Cheynier R. The infiltration kinetics of simian immunodeficiency virus-specific T cells drawn to sites of high antigenic stimulation determines local in vivo viral escape. Proc Natl Acad Sci U S A 2001; 98:13237-42. [PMID: 11687626 PMCID: PMC60854 DOI: 10.1073/pnas.231348598] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
Despite vigorous cell-mediated immune responses to human and simian immunodeficiency viruses (HIV/SIV) the immune system is unable to clear latently infected resting T cells. These infected cells are reactivated by antigenic stimulation, leading to viral replication. By using the SIV/macaque model of HIV pathogenesis, the dynamics of T cell infiltration into delayed type hypersensitivity sites specific for the purified protein derivative of bacillus Calmette-Guérin have been studied. Early viral mRNA synthesis coincided with the infiltration of antigen-specific T cells. When the infiltration of anti-SIV-specific T cells was rapid compared with the kinetics of viral assembly, the sites were sterilized before the transition to late viral mRNA synthesis occurred. When their infiltration was slow, ephemeral foci of replication were identified. These findings were paralleled by plasma viremia; low viremia coincided with rapid sterilization of the delayed type hypersensitivity sites, whereas high load was found in association with local replication and delayed sterilization. These data suggest that although effective local control of SIV is possible once antiviral T lymphocytes have arrived on site, the slower deployment of these T cells may allow the virus to escape and thus to reseed the pool of memory T cells.
Collapse
Affiliation(s)
- P Blancou
- Unité de Rétrovirologie Moléculaire, Institut Pasteur, 28, Rue du Dr. Roux, 75724 Paris Cedex 15, France
| | | | | | | | | | | |
Collapse
|
31
|
Dyrhol-Riise AM, Ohlsson M, Skarstein K, Nygaard SJ, Olofsson J, Jonsson R, Asjö B. T cell proliferation and apoptosis in HIV-1-infected lymphoid tissue: impact of highly active antiretroviral therapy. Clin Immunol 2001; 101:180-91. [PMID: 11683577 DOI: 10.1006/clim.2001.5102] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
T cell turnover was studied in situ in tonsillar lymphoid tissue (LT) from HIV-1-infected individuals during 48 weeks of highly active antiretroviral therapy (HAART) and compared to that of HIV-1-negative controls. Prior to therapy, CD4 cell proliferation (%CD4+ Ki67+) and apoptosis (%CD4+ TUNEL+) were increased in HIV-1-infected LT and both parameters correlated with tonsillar viral load. CD8 cell proliferation (%CD8+ Ki67+) was increased 4- to 10-fold, mainly in the germinal centers. Apoptotic CD8+ T cell levels (%CD8+ TUNEL+) were raised preferentially in the tonsillar T cell zone. The frequency of CD8+ Ki67+ and CD8+ TUNEL+ T cells correlated with tonsillar viral load and with the fraction of CD8(+) T cells expressing activation markers. During HAART, CD4 cell turnover normalized while CD8 cell turnover was dramatically reduced. However, low level viral replication concomitant with slightly elevated levels of CD8 cell turnover indicated a persistent cellular immune response in LT. In conclusion, enhanced T cell turnover may reflect effector cells related to HIV-1 infection.
Collapse
Affiliation(s)
- A M Dyrhol-Riise
- Centre for Research in Virology, Department of Microbiology and Immunology, P.O. Box 7800, University of Bergen, N-5020 Bergen, Norway.
| | | | | | | | | | | | | |
Collapse
|