A human T-cell clone cytotoxic for hepatocytes from patients with chronic non-A, non-B hepatitis

A human T-cell clone (TA-NB-2) which could lyse hepatocytes from patients with chronic non-A, non-B (NANB) hepatitis was established (Proc Natl Acad Sci USA 1989;86:2883-2887). TA-NB-2 cells belonged to CD3+ CD8+ cytotoxic T lymphocytes, and recognized the target hepatocytes by T-cell receptor without restriction by major histocompatibility complex (MHC) antigens. TA-NB-2 cells significantly lysed hepatocytes from 22 of 23 patients with chronic NANB hepatitis, whereas they lysed hepatocytes from only one of 17 control patients with chronic type B hepatitis, acute hepatitis B or acute hepatitis A. TA-NB-2 cells also significantly lysed hepatocytes from 4 of 5 patients with autoimmune liver disease. The results suggest that TA-NB-2 cells specifically recognize a NANB hepatitis-related antigen expressed on NANB hepatitis virus-infected hepatocytes by T-cell receptor in non-MHC-restricted manner. The results also suggest that most, if not all, cases of chronic NANB hepatitis are caused by one agent and that a portion of cases of autoimmune liver disease may be induced by infection with a NANB hepatitis virus.