title: Humoral immunity to immunodominant epitopes of Hepatitis C virus in individuals infected with genotypes 1a or 1b.
abstract: Cellular immunity against multiple Hepatitis C virus (HCV) proteins is observed in patients acutely infected with HCV most of whom later resolve infection. We wished to assess humoral immunity in patients infected with HCV 1a or 1b genotypes in relation to viral load using plasma samples from HCV-infected individuals and a panel of peptides representing immunodominant epitopes of HCV structural and nonstructural proteins. Plasma from HCV 1a- and 1b-infected patients, respectively, were divided into two groups: patients with low viral load (<==100,000 RNA copies/ml) and patients with high viral load (>/=10,000,000 RNA copies/ml). The antigens were peptides representing epitopes from immunodominant regions of HCV core, E2, NS3, and NS4 proteins, as well as the hypervariable (HVR) epitopes in E2 from genotypes 1a and 1b. Individuals infected with HCV 1a evoked a stronger immune response to many immunodominant epitopes of HCV relative to individuals infected with HCV 1b. Moreover, among individuals infected with HCV 1a, those with low viral loads mounted significantly greater responses against these epitopes than did individuals with high viral loads. Our observations demonstrate that quantitatively different antibody responses are elicited against HCV depending on the genotype of infecting virus, and suggest that humoral immunity directed against multiple immunodominant epitopes in HCV 1a-infected individuals may help lower viral load in vivo.
authors.affiliation: Department of Medical Microbiology and Immunology, School of Medicine, University of California, Davis, CA 95616, USA.
authors.forename: Maria P
authors.initials: MP
authors.lastname: Carlos
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Yamamura
authors.forename: Quynh
authors.initials: Q
authors.lastname: Vu
authors.forename: Kendra
authors.initials: K
authors.lastname: Conzen
authors.forename: David E
authors.initials: DE
authors.lastname: Anderson
authors.forename: José V
authors.initials: JV
authors.lastname: Torres
mesh_terms: D000917:Antibody Formation; D004797:Enzyme-Linked Immunosorbent Assay; D005838:Genotype; D016174:Hepacivirus / Q000235:genetics / Q000276:immunology*; D018937:Hepatitis C Antibodies / Q000276:immunology*; D006801:Humans; D016056:Immunodominant Epitopes; D010455:Peptides / Q000276:immunology; D014758:Viral Core Proteins / Q000276:immunology; D019562:Viral Load
chemical_list: D018937:Hepatitis C Antibodies; D016056:Immunodominant Epitopes; D010455:Peptides; D014758:Viral Core Proteins