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Boritz E, Rapaport EL, Campbell TB, Koeppe JR, Wilson CC. CD4+ T cell targeting of human immunodeficiency virus type 1 (HIV-1) peptide sequences present in vivo during chronic, progressive HIV-1 disease. Virology 2006; 361:34-44. [PMID: 17169395 PMCID: PMC5058783 DOI: 10.1016/j.virol.2006.10.040] [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: 06/27/2006] [Revised: 08/28/2006] [Accepted: 10/27/2006] [Indexed: 12/17/2022]
Abstract
We previously detected HIV-1 Gag-specific CD4+ T cells recognizing reference strain viral epitopes in subjects with progressive, chronic infection. To test whether these CD4+ T cells persist in vivo by failing to recognize autologous HIV-1 epitopes, we compared autologous plasma HIV-1 p24 nucleotide sequences with targeted HXB.2 strain Gag p24 CD4+ T cell epitopes in nine chronically infected, untreated subjects. In five responding subjects, 10 of 26 HXB.2 strain p24 peptides targeted by CD4+ T cells exactly matched autologous plasma viral sequences. Four subjects with plasma viral loads >100,000 copies/mL had no measurable p24-specific CD4+ T cell responses despite carrying HIV-1 strains that matched HXB.2 sequences at predicted epitopes. These results show that HIV-1-specific CD4+ T cells can persist in chronic HIV-1 infection despite recognition of epitopes present in vivo. However, with high-level in vivo HIV-1 replication, CD4+ T cells targeting autologous HIV-1 may be non-responsive or absent.
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Affiliation(s)
- Eli Boritz
- Department of Immunology, University of Colorado Health Sciences Center, Denver, CO, USA.
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52
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Munier ML, Kelleher AD. Acutely dysregulated, chronically disabled by the enemy within: T-cell responses to HIV-1 infection. Immunol Cell Biol 2006; 85:6-15. [PMID: 17146463 DOI: 10.1038/sj.icb.7100015] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Human immunodeficiency virus (HIV) infection causes chronic progressive immunodeficiency and immune dysregulaton. Although simple depletion of the major target of HIV infection, the CD4+ T cell, can explain much of the immunosuppression seen, there are multiple other factors contributing to the immune dysregulation. CD4+ T-cell depletion induces a range of homeostatic mechanisms that contribute to immune activation and cell turnover, providing a milieu conducive to further viral replication and cell destruction, resulting in functional defects in various lymphoid organs. These changes are progressive and in turn compromise the homeostatic processes. Further, the infection, like any other viral infection, provokes an active immune response consisting of both CD4+ and CD8+ T-cell responses. Both appear compromised, displaying aberrant memory cell production. While some of these defects result from viral variation and the chronicity of antigen presentation, other defects of memory cell production appear very early during the primary immune response limiting the viral specific T-cell responses from the outset. This, combined with the ability of the virus to escape any successful immune responses, results in an attenuated immune response that eventually becomes exhausted, characterized by progressive deficits in T-cell repertoire. Furthermore, negative regulatory mechanisms that normally control the immune response may be aberrantly invoked, perhaps directly by the virus, further compromising the efficacy of the immune response. Rational design of effective immunotherapies depends on a clear understanding of the processes compromising the immune response to HIV.
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Affiliation(s)
- M L Munier
- Centre for Immunology, St Vincent's Hospital, Sydney, Australia
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53
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Tilton JC, Johnson AJ, Luskin MR, Manion MM, Yang J, Adelsberger JW, Lempicki RA, Hallahan CW, McLaughlin M, Mican JM, Metcalf JA, Iyasere C, Connors M. Diminished production of monocyte proinflammatory cytokines during human immunodeficiency virus viremia is mediated by type I interferons. J Virol 2006; 80:11486-97. [PMID: 17005663 PMCID: PMC1642603 DOI: 10.1128/jvi.00324-06] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2006] [Accepted: 08/29/2006] [Indexed: 12/24/2022] Open
Abstract
The effect of human immunodeficiency virus (HIV) infection and high-level HIV replication on the function of monocytes was investigated. HIV-positive patients had elevated levels of spontaneous production of some or all of the monocyte proinflammatory cytokines measured (interleukin-1beta [IL-1beta], IL-6, and tumor necrosis factor alpha [TNF-alpha]) compared to uninfected controls. In patients on therapy with high frequencies of monocytes producing proinflammatory cytokines, this frequency was diminished in the context of viremia during an interruption of therapy. Diminished production of proinflammatory cytokines during viremia was restored by culture with autologous CD4(+) T cells or monocytes from an on-therapy time point or lipopolysaccharide (LPS). Microarray analysis demonstrated that diminished monocyte production of proinflammatory cytokines was correlated with elevated type I interferon-stimulated gene transcripts. The addition of exogenous alpha 2A interferon diminished the spontaneous production of IL-1beta, IL-6, and TNF-alpha but did not affect responses to LPS, recapitulating the changes observed for HIV-viremic patients. These results suggest that monocyte function is diminished during high-level HIV viremia and that this effect is mediated by chronic stimulation by type I interferons. This effect on monocytes during viremia may play a role in diminished innate or adaptive immune system functions in HIV-infected patients. In addition, the restoration of these functions may also play a role in some immune reconstitution syndromes observed during initiation of therapy.
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Affiliation(s)
- John C Tilton
- Laboratory of Immunoregulation, National Institute of Allergy and Infectious Diseases/NIH, Bldg 10, Rm 11B-09, 10 Center Drive, Bethesda, MD 20892-1876, USA
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54
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Ondondo BO, Yang H, Dong T, di Gleria K, Suttill A, Conlon C, Brown D, Williams P, Rowland-Jones SL, Hanke T, McMichael AJ, Dorrell L. Immunisation with recombinant modified vaccinia virus Ankara expressing HIV-1 gag in HIV-1-infected subjects stimulates broad functional CD4+ T cell responses. Eur J Immunol 2006; 36:2585-94. [PMID: 17013989 DOI: 10.1002/eji.200636508] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Virus-specific CD4+ T cells with IL-2-secreting and/or proliferative capacity are detected readily in HIV-1-infected long-term nonprogressors and rarely in persons with untreated progressive infection. The contribution of these cells to viraemia control is uncertain, but this question might be addressed in clinical therapeutic vaccination studies. However, the quality of T helper responses induced by currently available HIV-1 vaccine candidates has not been explored in depth. We determined the effect of vaccination with modified vaccinia virus Ankara (MVA) expressing HIV-1 gag p24/p17 (MVA.HIVA) on HIV-1-specific CD4+ T cell responses in 16 chronically infected, highly active antiretroviral therapy (HAART)-treated subjects using CD8-depleted IFN-gamma ELISPOT assays, intracellular cytokine staining assays for IL-2 and IFN-gamma, and a CFSE-based proliferation assay. Gag-specific CD4+ T cell responses were significantly increased in magnitude and breadth after vaccination and targeted both known and new epitopes, several of which were also recognised by healthy HIV-uninfected volunteers immunised with the same vaccines. The frequencies of CD4+ T cells expressing IL-2 or IFN-gamma, alone or simultaneously, were also augmented. These findings indicate that functional virus-specific T helper cells can be boosted by vaccination in chronic HIV-1 infection. Further evaluation of their role in viraemia control is warranted.
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Affiliation(s)
- Beatrice O Ondondo
- MRC Human Immunology Unit, Weatherall Institute of Molecular Medicine, John Radcliffe Hospital, Oxford, UK
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55
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Harari A, Dutoit V, Cellerai C, Bart PA, Du Pasquier RA, Pantaleo G. Functional signatures of protective antiviral T-cell immunity in human virus infections. Immunol Rev 2006; 211:236-54. [PMID: 16824132 DOI: 10.1111/j.0105-2896.2006.00395.x] [Citation(s) in RCA: 201] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
The most common human viruses have different abilities to establish persistent chronic infection. Virus-specific T-cell responses are critical in the control of virus replication and in the prevention of disease in chronic infection. A large number of phenotypic markers and a series of functions have been used to characterize virus-specific CD4+ and CD8+ T-cell responses, and these studies have shown great phenotypic and functional heterogeneity of the T-cell responses against different viruses. The heterogeneity of the T-cell response has been proposed to be specific to each virus. However, over the past 2 years, several studies have provided evidence that the phenotypic and functional heterogeneity of CD4+ and CD8+ T-cell responses is predominantly regulated by the levels of antigen load. The levels of antigen load modulate the phenotypic and functional patterns of the T-cell response within the same virus infection. Furthermore, the functional characterization of virus-specific CD4+ and CD8+ T-cell responses has identified signatures of protective antiviral immunity. Polyfunctional, i.e. interleukin-2 and interferon-gamma (IFN-gamma) secretion and proliferation, and not monofunctional, i.e. IFN-gamma secretion, CD4+ and CD8+ T-cell responses represent correlates of protective antiviral immunity in chronic virus infections.
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Affiliation(s)
- Alexandre Harari
- Laboratory of AIDS Immunopathogenesis, Division of Immunology and Allergy, Department of Medicine, Centre Hospitalier Universitaire Vaudois, University of Lausanne, Lausanne, Switzerland
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56
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Preclinical primate studies of HIV-1-envelope-based vaccines: towards human clinical trials. Curr Opin HIV AIDS 2006; 1:336-43. [DOI: 10.1097/01.coh.0000232350.61650.f0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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57
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Cohen WM, Pouvelle-Moratille S, Wang XF, Farci S, Munier G, Charron D, Ménez A, Busson M, Maillère B. Scanning the HIV genome for CD4+ T cell epitopes restricted to HLA-DP4, the most prevalent HLA class II molecule. THE JOURNAL OF IMMUNOLOGY 2006; 176:5401-8. [PMID: 16622007 DOI: 10.4049/jimmunol.176.9.5401] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
HLA-DP4 alleles are carried by 75% of individuals and are the most frequent HLA II alleles worldwide. Because we have recently characterized the peptide-binding specificity of HLA-DP4 molecules, we developed a peptide-binding prediction method to identify HLA-DP4-restricted peptides in multiple Ags. CD4(+) T cell response plays a key role in the immune control of HIV infection, but few HIV-specific T cell epitopes with multi-individual specificity have been identified. They are mostly restricted to HLA-DR molecules, which are very polymorphic molecules. We therefore looked for HLA-DP4-restricted CD4(+) T cell epitopes in the whole genome of HIV. Twenty-one peptides were selected from the HXB2 HIV genome based on the prediction of binding to HLA-DP4 molecules. They were submitted to HLA-DP4-binding assays. Seventeen peptides bound to the HLA-DP401 molecule, whereas 15 peptides bound to HLA-DP402. Six peptides bound very tightly to HLA-DP401 and were investigated for their capacity to induce specific CD4(+) T cell lines in vitro using dendritic cells and CD4(+) T cells collected from eight seronegative HLA-DP4(+) donors. Four peptides from env and reverse transcriptase proteins induced in vitro-specific T cell lines restricted to HLA-DP4 molecules. Peptide-induced T cells recognized variants other than the HXB2 sequence and were stimulated by native Ags processed by immature dendritic cells. The reverse transcriptase peptide is present in 65% of the isolated HIV variants. To our knowledge, we describe the first HIV epitopes restricted to HLA-DP4 molecules.
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Affiliation(s)
- William M Cohen
- Protein Engineering and Research Department, bâtiment 152, Commissariat à l'Energie Atomique Saclay, 91191 Gif sur Yvette, France
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58
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Moris A, Pajot A, Blanchet F, Guivel-Benhassine F, Salcedo M, Schwartz O. Dendritic cells and HIV-specific CD4+ T cells: HIV antigen presentation, T-cell activation, and viral transfer. Blood 2006; 108:1643-51. [PMID: 16675708 DOI: 10.1182/blood-2006-02-006361] [Citation(s) in RCA: 104] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Human immunodeficiency virus (HIV)-specific CD4+ lymphocytes are preferentially infected in HIV-positive individuals. To study this preferential infection, we have derived several HIV-specific (HS) CD4+ clones. We show that in dendritic cells (DCs), HIV virion capture led to major histocompatibility complex class-II (MHC-II)-restricted viral antigen presentation and to activation of HS cells. In contrast, neither cell-free virions nor infected lymphocytes activated HS cells. In DCs, the dendritic cell-specific intercellular adhesion molecule 3-grabbing nonintegrin (DC-SIGN/CD209), which internalizes virions, promoted MHC-II presentation of HIV antigens. Activation of HS cells by HIV-exposed DCs triggered an efficient viral spread in lymphocytes. CD4+ clones with irrelevant antigenic specificities were not activated by HIV-exposed DCs and poorly supported viral replication under this setting. Our results unravel the mechanisms of MHC-II-restricted HIV antigen presentation by DCs and describe how HIV gains access to the very cells designed by the immune system to counteract this pathogen.
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Affiliation(s)
- Arnaud Moris
- Groupe Virus et Immunité, Unité de Recherche Associée (URA) Centre National de la Recherche Scientifique (CNRS) 1930, Paris, France
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59
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Pantaleo G, Harari A. Functional signatures in antiviral T-cell immunity for monitoring virus-associated diseases. Nat Rev Immunol 2006; 6:417-23. [PMID: 16622477 DOI: 10.1038/nri1840] [Citation(s) in RCA: 156] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
At present, we only have indirect knowledge of the protective role of antigen-specific T cells in human viral infections, and it has been difficult to show a direct correlation between quantitative and qualitative measures of T-cell immunity and virus-associated diseases. However, as described in this Opinion article, recent advances in the characterization of T-cell functions and in the development of standardized T-cell assays have led to the identification of distinct functional signatures of T-cell responses that correlate with levels of viral replication and disease activity.
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Affiliation(s)
- Giuseppe Pantaleo
- Laboratory of AIDS Immunopathogenesis, Division of Immunology and Allergy, Department of Medicine, Centre Hospitalier Universitaire Vaudois, University of Lausanne, 1011 Lausanne, Switzerland.
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60
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Palmer BE, Blyveis N, Fontenot AP, Wilson CC. Functional and phenotypic characterization of CD57+CD4+ T cells and their association with HIV-1-induced T cell dysfunction. THE JOURNAL OF IMMUNOLOGY 2006; 175:8415-23. [PMID: 16339584 DOI: 10.4049/jimmunol.175.12.8415] [Citation(s) in RCA: 110] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
HIV-1 replication is associated with reduced or absent HIV-1-specific CD4+ T cell proliferation and skewing of HIV-1-specific CD4+ T cells toward an IFN-gamma-producing, CCR7- phenotype. The CCR7- T cell population is heterogeneous and can be subdivided based on the expression of CD57. Although CD57 expression on CD8+ T cells is associated with proliferation incompetence and replicative senescence, less is known about the function of CD57-expressing CD4+ T cells. In this study, the frequency, phenotype, and function of CD57+CD4+ T cells were evaluated in 25 HIV-1-infected subjects and 10 seronegative controls. CD57+CD4+ T cells were found to be proliferation incompetent, even after strong mitogen stimulation. Percentages of CD4+ T cells that expressed CD57 were significantly higher in untreated HIV-1-infected subjects than in HIV-1-seronegative donors, and CD57 expression did not normalize in subjects receiving at least 6 mo of effective antiretroviral therapy. CD57 was predominately expressed on the CCR7- fraction of the CD4+ T cell compartment and accounted for the majority of cells in the CCR7-CD45RA+ population from untreated HIV-1-infected subjects. HIV-1-specific CD4+ T cells producing only IFN-gamma had the highest expression of CD57, whereas few cells producing IL-2 alone expressed CD57. These findings further define a novel population of proliferation-incompetent CD4+ T cells that are generated in the presence of chronic Ag exposure. A better understanding of the generation and persistence of CD57+ T cells in HIV-1 infection could provide important insights into the immunopathogenesis of this disease.
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Affiliation(s)
- Brent E Palmer
- Department of Medicine, University of Colorado Health Sciences Center, Denver, CO 80262, USA
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61
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Jansen CA, van Baarle D, Miedema F. HIV-specific CD4+ T cells and viremia: who's in control? Trends Immunol 2006; 27:119-24. [PMID: 16458605 DOI: 10.1016/j.it.2006.01.004] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2005] [Revised: 12/19/2005] [Accepted: 01/17/2006] [Indexed: 12/14/2022]
Abstract
It has been proposed that HIV-specific CD4+ T cells with a central memory phenotype might be involved in controlling HIV replication. Based on recent data (lack of protective effects of HIV-specific CD4+ T-cell responses in acutely infected patients undergoing treatment interruptions; loss of initially strong T-helper cell responses in progressors to AIDS; and lack of prognostic value of HIV-specific CD4+ T cells in a prospective study) we argue that the level of persistent viremia determines the fate of HIV-specific CD4+ T cells. We postulate that, rather than the absence of HIV-specific T cells, it is the viral and immune activation set points that are major determinants of progression to AIDS. This influences ideas about the type of cellular immunity a protective HIV vaccine should induce.
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Affiliation(s)
- Christine A Jansen
- Department of Clinical Viro-Immunology, Sanquin Research and Landsteiner Laboratory of the Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
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62
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Koeppe JR, Campbell TB, Rapaport EL, Wilson CC. HIV-1-Specific CD4+ T-Cell Responses Are Not Associated With Significant Viral Epitope Variation in Persons With Persistent Plasma Viremia. J Acquir Immune Defic Syndr 2006; 41:140-8. [PMID: 16394844 DOI: 10.1097/01.qai.0000195608.32885.38] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVES To determine whether increased sequence variation occurs in regions of endogenous HIV-1 targeted by HIV-1-specific CD4 T cells. The presence of increased variation would be suggestive of immune evasion by HIV-1. DESIGN We performed a cross-sectional study of untreated HIV-1-infected subjects measuring HIV-1-specific interferon (IFN)-gamma-secreting CD4 T-cell responses against epitopes in Gag p17 and p24 and concurrent endogenous plasma HIV-1 RNA epitope sequence variation. METHODS CD8- depleted IFNgamma enzyme-linked immunospot assays were used to identify regions of HIV-1 Gag recognized by CD4 T cells. Reverse transcriptase polymerase chain reaction and TA cloning were used to sequence endogenous plasma HIV-1 virus and identify variants. RESULTS CD4 T-cell epitopes in Gag p17 and p24 were identified in 5 individuals, and concurrent sequence information on endogenous HIV-1 was obtained in 4 of these individuals. Endogenous plasma HIV-1 RNA sequencing revealed no intrapatient amino acid sequence variation through identified epitopes. CONCLUSIONS In these chronically infected viremic subjects, circulating IFNgamma-secreting CD4 T-cell responses were directed against epitope sequences found in the predominant strain of endogenous circulating plasma HIV-1, suggesting that escape from CD4 T-cell responses is not a common process in vivo.
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Affiliation(s)
- John R Koeppe
- Division of Infectious Diseases and Clinical Immunology, University of Colorado Health Sciences Center, Denver, CO 80262, USA.
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63
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Seth N, Kaufmann D, Lahey T, Rosenberg ES, Wucherpfennig KW. Expansion and contraction of HIV-specific CD4 T cells with short bursts of viremia, but physical loss of the majority of these cells with sustained viral replication. THE JOURNAL OF IMMUNOLOGY 2006; 175:6948-58. [PMID: 16272355 PMCID: PMC3414417 DOI: 10.4049/jimmunol.175.10.6948] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Chronic infection with the HIV results in poor HIV-specific CD4 T cell proliferation, but more recent analyses using intracellular cytokine staining demonstrated that IFN-gamma-producing, HIV-specific CD4 T cells can be detected for years in HIV-infected subjects. Because it is not known whether the majority of HIV-specific T cells are lost or become dysfunctional, we examined the kinetics of the T cell response over an extended period of time using a panel of 10 HLA-DR tetramers loaded with HIV p24 peptides. Tetramer+ CD4 T cells were present at a relatively high frequency during acute infection, but the size of these populations substantially contracted following suppression of viral replication. Short-term cessation of antiretroviral therapy resulted in a burst of viral replication and concomitant expansion of tetramer+ CD4 T cells, and these populations again contracted following reinitiation of therapy. The kinetics with which these cell populations contracted were characteristic of effector T cells, a conclusion that was supported by their phenotypic (CCR7-CD45RA-) and functional properties (IFN-gamma+). Continued high-level viremia resulted in the physical loss of the majority of tetramer+ CD4 T cells, and the decline of HIV p24-specific CD4 T cells occurred more rapidly and was more substantial than the reduction of total CD4 T cell numbers. We conclude that the population of HIV p24-specific CD4 T cells is initially responsive to changes in the levels of viral Ags, but that the majority of these cells are lost in a setting of chronic viremia.
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Affiliation(s)
- Nilufer Seth
- Department of Cancer Immunology & AIDS, Dana-Farber Cancer Institute, Boston MA 02115
- Department of Pathology, Harvard Medical School, Boston, MA 02115
| | - Daniel Kaufmann
- Infectious Disease Unit, Massachusetts General Hospital, Boston, MA 02114
- Department of Medicine, Harvard Medical School, Boston, MA 02115
| | - Timothy Lahey
- Infectious Disease Unit, Massachusetts General Hospital, Boston, MA 02114
- Infectious Diseases and International Health, Dartmouth-Hitchcock Medical Center, Lebanon, NH 03755
- Division of Infectious Diseases, Beth Israel Deaconess Medical Center, Boston, MA 02215
- Department of Medicine, Harvard Medical School, Boston, MA 02115
| | - Eric S. Rosenberg
- Infectious Disease Unit, Massachusetts General Hospital, Boston, MA 02114
- Department of Medicine, Harvard Medical School, Boston, MA 02115
| | - Kai W. Wucherpfennig
- Department of Cancer Immunology & AIDS, Dana-Farber Cancer Institute, Boston MA 02115
- Department of Neurology, Harvard Medical School, Boston, MA 02115
- Program in Immunology, Harvard Medical School, Boston, MA 02115
- Address correspondence and reprint requests to Dr. Kai Wucherpfennig, Department of Cancer Immunology & AIDS, Dana-Farber Cancer Institute, 44 Binney Street, Boston, MA 02115.
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64
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Jansen CA, Piriou E, De Cuyper IM, van Dort K, Lange JMA, Miedema F, van Baarle D. Long-Term Highly Active Antiretroviral Therapy in Chronic HIV-1 Infection: Evidence for Reconstitution of Antiviral Immunity. Antivir Ther 2006. [DOI: 10.1177/135965350601100104] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
In this study we investigated the long-term effect of highly active antiretroviral therapy (HAART) on HIV-specific CD4+ T-cell responses in comparison with virus-specific CD4+ T-cell responses against the persistent herpes viruses cytomegalovirus (CMV) and Epstein-Barr virus (EBV). To this end, HIV- and herpes virus-specific cellular immune responses were measured longitudinally in 10 seroconverters with long-term follow-up including 55 months of successful suppression of viral load by HAART. HIV- and CMV-specific CD4+ T cells producing interferon-γ (IFNγ) or interleukin-2 (IL-2) were analysed as well as proliferative capacity. EBV-specific CD4+ T cells were determined using a 12-day ex vivo assay. Initiation of HAART resulted in a transient increase of HIV-specific IL-2+IFNγ+CD4+ T cells and, to a lesser extent, IL-2+CD4+ T cells. Long-term HAART resulted in an increase in HIV-, CMV- and EBV-specific CD4+ T-cell proliferative capacity. The increase in HIV- and herpes-virus-specific CD4+ T-cell proliferative capacity after 55 months of HAART suggests that the improved proliferative response is not specific for HIV, but reflects a more general improvement of antiviral immune responses, which is induced by HAART.
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Affiliation(s)
- Christine A Jansen
- Department of Clinical Viro-Immunology, Sanquin Research at CLB and Landsteiner Laboratory
| | - Erwan Piriou
- Department of Clinical Viro-Immunology, Sanquin Research at CLB and Landsteiner Laboratory
| | - Iris M De Cuyper
- Department of Clinical Viro-Immunology, Sanquin Research at CLB and Landsteiner Laboratory
| | - Karel van Dort
- Department of Clinical Viro-Immunology, Sanquin Research at CLB and Landsteiner Laboratory
| | - Joep MA Lange
- Department of Human Retrovirology, Academic Medical Center, University of Amsterdam, Amsterdam, the Netherlands
- Department of Internal Medicine, Division of Infectious Diseases, Tropical Medicine and AIDS, Academic Medical Center, University of Amsterdam, the Netherlands
| | - Frank Miedema
- Department of Clinical Viro-Immunology, Sanquin Research at CLB and Landsteiner Laboratory
| | - Debbie van Baarle
- Department of Clinical Viro-Immunology, Sanquin Research at CLB and Landsteiner Laboratory
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65
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Spectrum of CD4 T-cell recovery during prolonged treatment with highly active antiretroviral therapy. Curr Opin HIV AIDS 2006; 1:50-5. [DOI: 10.1097/01.coh.0000194107.20439.91] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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66
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67
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Geels MJ, Jansen CA, Baan E, De Cuyper IM, van Schijndel GJM, Schuitemaker H, Goudsmit J, Pollakis G, Miedema F, Paxton WA, van Baarle D. CTL escape and increased viremia irrespective of HIV-specific CD4+ T-helper responses in two HIV-infected individuals. Virology 2005; 345:209-19. [PMID: 16246391 DOI: 10.1016/j.virol.2005.09.023] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2005] [Revised: 08/26/2005] [Accepted: 09/15/2005] [Indexed: 12/15/2022]
Abstract
We investigated whether development of mutations leads to loss of CD8 T-cell recognition in HIV-1 infection and is possibly linked to alterations in HIV-1-specific CD4(+) T-cell responses in 2 HIV-infected individuals. In patient, H434 full genome sequencing of HIV-1 biological clones at early and late time points during disease progression showed development of fixed mutations in 16 predicted HIV-specific CTL epitopes. Loss of T-cell recognition and reactivity against wild-type and mutant epitopes was observed primarily for the HLA-B27-restricted KK10 epitope and HLA-A2-restricted SL9 epitope. Similarly, in patient H671, decreasing numbers of HLA-A3-restricted CD8(+) T cells specific for the wild-type RK9 epitope was observed after CTL escape. Only in patient H434 loss of CTL responses was paralleled by a decrease in HIV-specific IL-2(+) CD4(+) T-helper responses. This suggests that loss of T-cell reactivity may not be directly linked to HIV-specific CD4(+) T-cell responses but that increased viremia after CTL escape may influence CD4(+) T-helper responses.
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Affiliation(s)
- Mark J Geels
- Department of Human Retrovirology, Academic Medical Centre, University of Amsterdam, The Netherlands.
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Fontenot AP, Palmer BE, Sullivan AK, Joslin FG, Wilson CC, Maier LA, Newman LS, Kotzin BL. Frequency of beryllium-specific, central memory CD4+ T cells in blood determines proliferative response. J Clin Invest 2005; 115:2886-93. [PMID: 16151531 PMCID: PMC1199530 DOI: 10.1172/jci24908] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2005] [Accepted: 07/01/2005] [Indexed: 11/17/2022] Open
Abstract
Beryllium exposure can lead to the development of beryllium-specific CD4+ T cells and chronic beryllium disease (CBD), which is characterized by the presence of lung granulomas and a CD4+ T cell alveolitis. Studies have documented the presence of proliferating and cytokine-secreting CD4+ T cells in blood of CBD patients after beryllium stimulation. However, some patients were noted to have cytokine-secreting CD4 T cells in blood in the absence of beryllium-induced proliferation, and overall, the correlation between the 2 types of responses was poor. We hypothesized that the relative proportion of memory T cell subsets determined antigen-specific proliferation. In most CBD patients, the majority of beryllium-specific CD4+ T cells in blood expressed an effector memory T cell maturation phenotype. However, the ability of blood cells to proliferate in the presence of beryllium strongly correlated with the fraction expressing a central memory T cell phenotype. In addition, we found a direct correlation between the percentage of beryllium-specific CD4+ T(EM) cells in blood and T cell lymphocytosis in the lung. Together, these findings indicate that the functional capability of antigen-specific CD4+ T cells is determined by the relative proportion of memory T cell subsets, which may reflect internal organ involvement.
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Affiliation(s)
- Andrew P Fontenot
- Division of Clinical Immunology, Department of Medicine, University of Colorado Health Sciences Center, Denver, Colorado, USA.
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69
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Jansen CA, De Cuyper IM, Steingrover R, Jurriaans S, Sankatsing SUC, Prins JM, Lange JMA, van Baarle D, Miedema F. Analysis of the effect of highly active antiretroviral therapy during acute HIV-1 infection on HIV-specific CD4 T cell functions. AIDS 2005; 19:1145-54. [PMID: 15990567 DOI: 10.1097/01.aids.0000176214.17990.94] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND It has been reported that antiretroviral therapy (HAART) during acute HIV-1 infection may rescue HIV-1-specific CD4 T cell responses. OBJECTIVE To determine the duration of this preserved response by investigating the long-term effects of HAART during acute infection on HIV-specific CD4 T cell function related to possible immune control during subsequent therapy interruption. METHODS A longitudinal analysis followed HIV-specific CD4 T cell reactivity in 17 individuals with well-documented acute HIV-1 infection where five out of 11 HAART-treated patients stopped therapy and six were untreated. Peripheral blood mononuclear cells were stimulated with overlapping peptide pools derived from Gag and Nef. Production of interferon-gamma (IFN-gamma) and interleukin-2 (IL-2) by CD4 T cells was analysed together with proliferative responses. RESULTS Absolute numbers, but not percentages, of Gag-specific IFN-gamma-, IL-2- or IFN-gamma/IL-2-producing CD4 T cells were increased in treated compared with untreated individuals up to 2 years after seroconversion. HAART during acute HIV-1 infection was associated with lower viral load but did not result in increased proliferation of HIV-specific CD4 T cells. One out of five individuals who discontinued therapy showed evidence for immune control. However, patients who failed to control viraemia also had measurable proliferative HIV-specific CD4 T cell responses and preserved numbers of cytokine-producing CD4 T cells. CONCLUSIONS Early HAART during acute HIV-1 infection resulted in higher numbers of HIV-specific IFN-gamma- and IL-2-producing CD4 T cells, but this preservation in four out of five patients was not associated with control of viraemia upon treatment interruption.
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Affiliation(s)
- Christine A Jansen
- Department of Clinical Viro-Immunology, Sanquin Research and Landsteiner Laboratory, University of Amsterdam, the Netherlands
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70
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García F, Ruiz L, López-Bernaldo de Quirós JC, Moreno S, Domingo P. Inmunoterapia y vacunas terapéuticas en la infección por VIH. Enferm Infecc Microbiol Clin 2005. [DOI: 10.1016/s0213-005x(05)75164-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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71
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García F, Ruiz L, López-Bernaldo de Quirós JC, Moreno S, Domingo P. Immunotherapy and therapeutic vaccines in HIV infection. Enferm Infecc Microbiol Clin 2005. [DOI: 10.1016/s0213-005x(05)75165-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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72
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Zaunders JJ, Munier ML, Kaufmann DE, Ip S, Grey P, Smith D, Ramacciotti T, Quan D, Finlayson R, Kaldor J, Rosenberg ES, Walker BD, Cooper DA, Kelleher AD. Early proliferation of CCR5(+) CD38(+++) antigen-specific CD4(+) Th1 effector cells during primary HIV-1 infection. Blood 2005; 106:1660-7. [PMID: 15905189 DOI: 10.1182/blood-2005-01-0206] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
We investigated whether HIV-1 antigen-specific CD4(+) T cells expressed the viral coreceptor CCR5 during primary HIV-1 infection (PHI). In the peripheral blood of subjects with very early PHI (< 22 days after onset of symptoms), there was a 10- to 20-fold increase in the proportion of highly activated (CD38(+++)) and proliferating (Ki-67(+)) CD4(+) T cells that expressed CCR5(+), and were mostly T-cell intracellular antigen-1 (TIA-1)(+) perforin(+) granzyme B(+). Inthe same patient samples, CD4(+) T cells producing interferon (IFN)-gamma in response to HIV group-specific antigen (Gag) peptides were readily detected (median, 0.58%) by intracellular cytokine assay-these cells were again predominantly CD38(+++), Ki-67(+), and TIA-(++), as well as Bcl-2(low). On average, 20% of the Gag-specific CD4(+) T cells also expressed interleukin-2 (IL-2) and were CD127 (IL-7R)(+). Taken together, these results suggest that Gag-specific T-helper 1 (Th1) effector cells express CCR5 during the primary response and may include precursors of long-term self-renewing memory cells. However, in PHI subjects with later presentation, antigen-specific CD4(+) T cells could not be readily detected (median, 0.08%), coinciding with a 5-fold lower level of the CCR5(+)CD38(+++) CD4(+) T cells. These results suggest that the antiviral response to HIV-1 infection includes highly activated CCR5(+)CD4(+) cytotoxic effector cells, which are susceptible to both apoptosis and cytopathic infection with HIV-1, and rapidly decline.
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Affiliation(s)
- John J Zaunders
- Centre for Immunology, St Vincent's Hospital, Victoria St, Darlinghurst, NSW 2010 Australia.
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73
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Sun Y, Schmitz JE, Acierno PM, Santra S, Subbramanian RA, Barouch DH, Gorgone DA, Lifton MA, Beaudry KR, Manson K, Philippon V, Xu L, Maecker HT, Mascola JR, Panicali D, Nabel GJ, Letvin NL. Dysfunction of simian immunodeficiency virus/simian human immunodeficiency virus-induced IL-2 expression by central memory CD4+ T lymphocytes. THE JOURNAL OF IMMUNOLOGY 2005; 174:4753-60. [PMID: 15814700 DOI: 10.4049/jimmunol.174.8.4753] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Production of IL-2 and IFN-gamma by CD4+ T lymphocytes is important for the maintenance of a functional immune system in infected individuals. In the present study, we assessed the cytokine production profiles of functionally distinct subsets of CD4+ T lymphocytes in rhesus monkeys infected with pathogenic or attenuated SIV/simian human immunodeficiency virus (SHIV) isolates, and these responses were compared with those in vaccinated monkeys that were protected from immunodeficiency following pathogenic SHIV challenge. We observed that preserved central memory CD4+ T lymphocyte production of SIV/SHIV-induced IL-2 was associated with disease protection following primate lentivirus infection. Persisting clinical protection in vaccinated and challenged monkeys is thus correlated with a preserved capacity of the peripheral blood central memory CD4+ T cells to express this important immunomodulatory cytokine.
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Affiliation(s)
- Yue Sun
- Division of Viral Pathogenesis, Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02115, USA
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74
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Kolber MA. Impact of immune plasticity on development of cellular memory responses to human immunodeficiency virus type 1. CLINICAL AND DIAGNOSTIC LABORATORY IMMUNOLOGY 2005; 11:1002-7. [PMID: 15539497 PMCID: PMC524776 DOI: 10.1128/cdli.11.6.1002-1007.2004] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Affiliation(s)
- Michael A Kolber
- Division of Infectious Diseases, Department of Medicine, University of Miami School of Medicine, Miami, Florida 33101, USA.
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75
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Schenal M, Lo Caputo S, Fasano F, Vichi F, Saresella M, Pierotti P, Villa ML, Mazzotta F, Trabattoni D, Clerici M. Distinct patterns of HIV-specific memory T lymphocytes in HIV-exposed uninfected individuals and in HIV-infected patients. AIDS 2005; 19:653-61. [PMID: 15821391 DOI: 10.1097/01.aids.0000166088.85951.25] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
BACKGROUND Repeated exposure to HIV is not always associated with infection and multiple cohorts of HIV-exposed but seronegative individuals (ESN) have been described. HIV-specific CD4 and CD8 T lymphocytes are detected both in HIV patients and in ESN; we verified whether different patterns of HIV-specific memory T lymphocytes would be detected in individuals in whom exposure to HIV results or does not result in infection. METHODS Gag-specific T cells were analysed in 15 ESN, 14 HIV patients, and 15 healthy controls using extensive flow cytometry analysis. RESULTS Data confirmed that gag-specific T lymphocytes are present in ESN. Gag-specific T cells mainly secrete interleukin-2 in ESN and interferon-gamma in HIV patients. In addition the CD4/CD8 and the memory/naive ratios are altered, central memory (45RA-/CCR7+) CD4 and CD8 T lymphocytes are more abundant, and terminally differentiated (45RA+/CCR7- and 27-/28-) CD8 T lymphocytes are augmented in ESN individuals. CONCLUSIONS Exposure to HIV occurs in high risk seronegative individuals; the observation that naive cells and CM are skewed in ESN indicate that this exposure is robust enough to modulate the CM/EM ratio. The increase in late effectors and in natural killer cells seen in ESN suggests a role for these cells in preventing actual infection.
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Affiliation(s)
- Monica Schenal
- Immunology DISP LITA Vialba, University of Milano, Milano, Italy
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76
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Scriba TJ, Zhang HT, Brown HL, Oxenius A, Tamm N, Fidler S, Fox J, Weber JN, Klenerman P, Day CL, Lucas M, Phillips RE. HIV-1-specific CD4+ T lymphocyte turnover and activation increase upon viral rebound. J Clin Invest 2005; 115:443-50. [PMID: 15668739 PMCID: PMC544605 DOI: 10.1172/jci23084] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2004] [Accepted: 11/23/2004] [Indexed: 11/17/2022] Open
Abstract
HIV-specific CD4+ T helper lymphocytes are preferred targets for infection. Although complete interruption of combination antiretroviral therapy (ART) can form part of therapeutic manipulations, there is grave concern that the resumption of viral replication might destroy, perhaps irreversibly, these T helper populations. High viremia blocks the proliferation capacity of HIV-specific helper cells. However, cytokine production assays imply that some antigen-specific effector function is retained. Despite this careful work, it remains unclear whether the return of HIV-1 replication physically destroys HIV-1-specific T helper cells in the peripheral blood. Difficulties in producing stable peptide-MHC class II complexes and the very low frequencies of antigen-specific CD4+ T cells have delayed the application of this powerful technique. Here we employ HLA class II tetramers and validate a sensitive, quantitative cell-enrichment technique to detect HIV-1 T helper cells. We studied patients with early-stage HIV infection who were given a short, fixed course of ART as part of a clinical study. We did not find significant deletion of these cells from the peripheral circulation when ART was stopped and unfettered HIV replication returned. The turnover of these virus-specific cells increased and they adopted an effector phenotype when viremia returned.
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Affiliation(s)
- Thomas J Scriba
- Peter Medawar Building for Pathogen Research and Nuffield Department of Clinical Medicine, University of Oxford, Oxford, United Kingdom
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Arrode G, Finke JS, Zebroski H, Siegal FP, Steinman RM. CD8+ T cells from most HIV-1-infected patients, even when challenged with mature dendritic cells, lack functional recall memory to HIV gag but not other viruses. Eur J Immunol 2005; 35:159-70. [PMID: 15580653 DOI: 10.1002/eji.200425744] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Chronically HIV-1-infected patients fail to contain their viremia despite high frequencies of HIV-1-specific, IFN-gamma-producing CD8(+) T cells. However, these cells are known to exhibit both phenotypic and functional defects. We tested if mature dendritic cells (DC) could correct defective HIV-1 gag-specific T cell responses and if responses to other viral antigens were comparably affected. The circulating gag-specific CD8(+) T cells in fresh blood reliably produced IFN-gamma but lacked IL-2 and high perforin levels and failed to expand significantly during culture with mature DC presenting HIV-1 gag peptides. In contrast, CD8(+) T cells from long-term nonprogressors contained gag-specific IFN-gamma and IL-2 double producers, and the numbers of IFN-gamma producers expanded approximately 15-fold during culture with DC. DC from chronically infected patients could expand IFN-gamma- and IL-2-producing cells specific for influenza, cytomegalovirus and Epstein Barr virus, and the expansions were comparable to those in healthy donors. When the proliferative capacity of CD8(+) T cells from progressor patients was assessed by CFSE dilution, proliferation to other viral antigens was more vigorous than to HIV-1 gag. Therefore, monocyte-derived DC from HIV patients present viral antigens effectively, but there is a selective inability to expand CD8(+) IFN-gamma-producing and IFN-gamma and IL-2 double-producing T cells when challenged with HIV-1 gag.
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Affiliation(s)
- Geraldine Arrode
- Laboratory of Cellular Physiology and Immunology, The Rockefeller University, New York, NY 10021, USA
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78
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Scriba TJ, Zhang HT, Brown HL, Oxenius A, Tamm N, Fidler S, Fox J, Weber JN, Klenerman P, Day CL, Lucas M, Phillips RE. HIV-1–specific CD4+ T lymphocyte turnover and activation increase upon viral rebound. J Clin Invest 2005. [DOI: 10.1172/jci200523084] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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79
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Boritz E, Palmer BE, Wilson CC. Human immunodeficiency virus type 1 (HIV-1)-specific CD4+ T cells that proliferate in vitro detected in samples from most viremic subjects and inversely associated with plasma HIV-1 levels. J Virol 2004; 78:12638-46. [PMID: 15507650 PMCID: PMC525069 DOI: 10.1128/jvi.78.22.12638-12646.2004] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Diminished in vitro proliferation of human immunodeficiency virus type 1 (HIV-1)-specific CD4+T cells has been associated with HIV-1 viremia and declining CD4+ T-cell counts during chronic infection. To better understand this phenomenon, we examined whether HIV-1 Gag p24 antigen-induced CD4+ T-cell proliferation might recover in vitro in a group of subjects with chronic HIV-1 viremia and no history of antiretroviral therapy (ART). We found that depletion of CD8+ cells from peripheral blood mononuclear cells (PBMC) before antigen stimulation was associated with a 6.5-fold increase in the median p24-induced CD4+ T-cell proliferative response and a 57% increase in the number of subjects with positive responses. These p24-induced CD4+ T-cell proliferative responses from CD8-depleted PBMC were associated with expansion of the numbers of p24-specific, gamma interferon (IFN-gamma)-producing CD4+ T cells. Among the 20 viremic, treatment-naive subjects studied, the only 5 subjects lacking proliferation-competent, p24-specific CD4+ T-cell responses from CD8-depleted PBMC showed plasma HIV-1 RNA levels > 100,000 copies/ml. Furthermore, both the magnitude of p24-induced CD4+ T-cell proliferative responses from CD8-depleted PBMC and the frequency of p24-specific, IFN-gamma-producing CD4+ T cells expanded from CD8-depleted PBMC were associated inversely with plasma HIV-1 RNA levels. Therefore, proliferation-competent, HIV-1-specific CD4+ T cells that might help control HIV-1 disease may persist during chronic, progressive HIV-1 disease except at very high levels of in vivo HIV-1 replication.
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Affiliation(s)
- Eli Boritz
- University of Colorado Health Sciences Center, Campus Box B-164, 4200 East 9th Avenue, Denver, CO 80262, USA
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