IDENTIFICATION AND CHARACTERIZATION OF A CYTOTOXIC T-CELL EPITOPE OF HEPATITIS-C VIRUS PRESENTED BY HLA-B-ASTERISK-3501 IN ACUTE HEPATITIS

In order to clarify the role of cytotoxic T lymphocytes (CTL) in hepat itis C virus (HCV) infection, an HLA-B35-restricted cytotoxic T cell e pitope of HCV was identified using a strategy called reverse immunogen etics. Twenty-eight of 53 HCV peptides carrying two anchor residues we re selected as HLA-B3501 binding peptides. These peptides were used t o induce the specific cytotoxic T cells in peripheral blood lymphocyte s from a patient with acute hepatitis C. Six HLA-B3501 binding peptid es induced the peptide-specific CTL. One (HPNIEEVAL) of five peptides was confirmed as the epitope by the specific T cell clones. A sequence identical to the epitope was detected in isolates of the virus from t he patient and a strong CTL response to this epitope was observed in t he acute phase of hepatitis C but not in the recovery phase. The speci fic CTL for this epitope were not detected in peripheral blood lymphoc ytes from patients with chronic hepatitis C. Together these results su ggest that the CTL specific for this epitope have an important role in the elimination of the virus in the patient.