title: Differences in HCV-specific T cell responses between chronic HCV infection and HIV/HCV co-infection.
abstract: Hepatitis C virus (HCV)-specific CD4+ and CD8+ T cell responses were investigated using a panel of 728 overlapping peptides spanning the whole HCV genome in 47 HCV mono-infected and 26 HIV/HCV co-infected individuals using the IFN-gamma ELISPOT assay and flow cytometry. The frequency of HCV-specific T cell responses was similar (approximately 40%) in both groups, but the breadth of the T cell responses tended to be reduced in HIV/HCV co-infected individuals. Of interest, 23 new HCV-derived epitopes were identified, and CD4+ HCV-specific T cell responses were detected overall in a proportion similar to CD8+ T cell responses. A tendency towards a dominant CD8+ T cell response was associated with HIV/HCV co-infection. HCV-specific CD8+ T cells secreted both IL-2 and IFN-gamma, although a reduction in the percentage of IL-2/IFN-gamma-secreting cells was observed in HIV/HCV co-infected individuals. The increase in CD4+ T cell counts after antiretroviral therapy in HIV/HCV co-infected individuals was not associated with restoration of HCV-specific T cell responses. Altogether, these results provide new insights into the characterization of HCV-specific T cell responses in HCV mono-infected and HIV/HCV co-infected individuals.
authors.affiliation: Laboratory of AIDS Immunopathogenesis, Division of Immunology and Allergy, Department of Medicine, Centre Hospitalier Universitaire Vaudois, Lausanne, Switzerland.
authors.forename: Valérie
authors.initials: V
authors.lastname: Dutoit
authors.forename: Donatella
authors.initials: D
authors.lastname: Ciuffreda
authors.forename: Denis
authors.initials: D
authors.lastname: Comte
authors.forename: Jean-Jacques
authors.initials: JJ
authors.lastname: Gonvers
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Pantaleo
mesh_terms: D000328:Adult; D000595:Amino Acid Sequence; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology; D002908:Chronic Disease; D015897:Comorbidity; D005260:Female; D006678:HIV / Q000276:immunology*; D015658:HIV Infections / Q000276:immunology*; D016174:Hepacivirus / Q000276:immunology*; D006526:Hepatitis C / Q000276:immunology*; D006801:Humans; D008297:Male; D008969:Molecular Sequence Data; D013601:T-Lymphocytes / Q000276:immunology*