Epitopes described in "Characterization of CD8+ T-cell response in acute and resolved hepatitis A virus infection."

Reference
Article Authors:I Schulte; T Hitziger; S Giugliano; J Timm; H Gold; F M Heinemann; Y Khudyakov; M Strasser; C K├Ânig; E Castermans; J Y Mok; W J E van Esch; A Bertoletti; T N Schumacher; M Roggendorf
Article Title:Characterization of CD8+ T-cell response in acute and resolved hepatitis A virus infection.
Reference Detail
Reference ID:1021620
Abstract:BACKGROUND & AIMS: In contrast to the infection with other hepatotropic viruses, hepatitis A virus (HAV) always causes acute self-limited hepatitis, although the role for virus-specific CD8 T cells in viral containment is unclear. Herein, we analyzed the T cell response in patients with acute hepatitis by utilizing a set of overlapping peptides and predicted HLA-A2 binders from the polyprotein. METHODS: A set of 11 predicted peptides from the HAV polyprotein, identified as potential binders, were synthesized. Peripheral blood mononuclear cells (PBMCs) from patients were tested for IFN secretion after stimulation with these peptides and ex vivo with HLA-A2 tetramers. Phenotyping was carried out by staining with the activation marker CD38 and the memory marker CD127. RESULTS: Eight out of 11 predicted HLA-A2 binders showed a high binding affinity and five of them were recognized by CD8+ T cells from patients with hepatitis A. There were significant differences in the magnitude of the responses to these five peptides. One was reproducibly immunodominant and the only one detectable ex vivo by tetramer staining of CD8+ T cells. These cells have an activated phenotype (CD38hi CD127lo) during acute infection. Three additional epitopes were identified in HLA-A2 negative patients, most likely representing epitopes restricted by other HLA-class I-alleles (HLA-A11, B35, B40). CONCLUSIONS: Patients with acute hepatitis A have a strong multi-specific T cell response detected by ICS. With the tetramer carrying the dominant HLA-A2 epitope, HAV-specific and activated CD8+ T cells could be detected ex vivo. This first description of the HAV specific CTL-epitopes will allow future studies on strength, breadth, and kinetics of the T-cell response in hepatitis A.
Affiliations:Institute of Virology, University of Duisburg-Essen, Virchowstrasse 179, D-45147 Essen, Germany.
Date:2011
Reference Type:Literature
PubMed ID:21056495
Journal:J Hepatol
Journal Volume:54
Article Pages:201-8
Journal ISSN:0168-8278
Article Chemical List:Epitopes;HLA-A2 Antigen
Article MeSH List:Acute Disease; Adolescent; Adult; Aged; CD8-Positive T-Lymphocytes(immunology); Epitopes; Female; HLA-A2 Antigen(metabolism); Hepatitis A(immunology); Hepatitis A virus(immunology); Humans; Male; Middle Aged
Curation Last Updated:2014-10-03 22:18:09