title: CD8+ T-Cell Responses in Hepatitis B and C: The (HLA-) A, B, and C of Hepatitis B and C.
abstract: Approximately 500 million people are chronically infected with the hepatitis B virus (HBV) or hepatitis C virus (HCV) worldwide and are thus at high risk of progressive liver disease, leading to liver fibrosis, cirrhosis and ultimately hepatocellular cancer. Virus-specific CD8+ T-cells play a major role in viral clearance in >90% of adult patients who clear HBV and in approximately 30% of patients who clear HCV in acute infection. However, several mechanisms contribute to the failure of the adaptive CD8+ T-cell response in those patients who progress to chronic infection. These include viral mutations leading to escape from the CD8+ T-cell response as well as exhaustion and dysfunction of virus-specific CD8+ T-cells. Antiviral efficacy of the virus-specific CD8+ T-cell response also strongly depends on its restriction by specific human leukocyte antigens (HLA) class I alleles. Our review will summarize the role of HLA-A, B and C-restricted CD8+ T-cells in HBV and HCV infection. Due to the current lack of a comprehensive database of HBV- and HCV-specific CD8+ T-cell epitopes, we also provide a summary of the repertoire of currently well-described HBV- and HCV-specific CD8+ T-cell epitopes. A better understanding of the factors that contribute to the success or failure of virus-specific CD8+ T-cells may help to develop new therapeutic options for HBV eradication in patients with chronic HBV infection (therapeutic vaccination and/or immunomodulation) as well as a prophylactic vaccine against HCV infection.
authors.affiliation: Department of Medicine II, Freiburg University Medical Center, Freiburg, Germany.
authors.forename: Katja
authors.initials: K
authors.lastname: Nitschke
authors.forename: Hendrik
authors.initials: H
authors.lastname: Luxenburger
authors.forename: Muthamia M
authors.initials: MM
authors.lastname: Kiraithe
authors.forename: Robert
authors.initials: R
authors.lastname: Thimme
authors.forename: Christoph
authors.initials: C
authors.lastname: Neumann-Haefelin
mesh_terms: D000328:Adult; D000998:Antiviral Agents / Q000276:immunology; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology*; D018984:Epitopes, T-Lymphocyte / Q000276:immunology; D016174:Hepacivirus / Q000276:immunology; D006509:Hepatitis B / Q000276:immunology*; D006515:Hepatitis B virus / Q000276:immunology; D006526:Hepatitis C / Q000276:immunology*; D015395:Histocompatibility Antigens Class I / Q000276:immunology*; D006801:Humans
chemical_list: D000998:Antiviral Agents; D018984:Epitopes, T-Lymphocyte; D015395:Histocompatibility Antigens Class I