Analysis of a successful immune response against hepatitis C virus.

The CD8+ CTL line 3C was shown to recognize the epitope restricted by B*2001. Epitope-specific CTL lines were established from positively-selected CD8+ T cells extracted from an eleventh week liver biopsy of a chimpanzee and non-antigenically expanded in culture. The animal resolved HCV infection within 11 weeks and concurrently mounted an intrahepatic CTL response against multiple HCV proteins. Epitope-specific CD8+ CTL were also derived from liver biopsies taken 81 weeks following termination of HCV infection and expanded non-antigenically in vitro. The authors conclude that the ability to recover epitope-specific CTL from a healthy liver 1.5 yr after resolution of infection provides evidence for the existence of HCV-specific memory.