• α-interferon;
  • cytotoxic T cell;
  • hepatitis B virus.

Abstract To study the mechanism of the effects of α-interferon (α-IFN) on chronic hepatitis B, we examined its effect on hepatitis B virus (HBV)-specific cytotoxic T cells (CTL). Using two different HBV-DNA transfected human myeloma cell lines, one expressing hepatitis B core antigen (HBcAg; C4) and the other expressing hepatitis B surface antigen (HBsAg; S6) as targets in cytotoxic tests in vitro, peripheral blood mononuclear cells obtained from chronic hepatitis B patients who were treated with α-IFN were examined for their cytotoxic activity against these transfectants. During the treatment with α-IFN, in association with a decline of serum alanine amino transferase levels, CTL activities were significantly reduced. An inhibition study in vitro revealed that α-IFN did not directly inhibit these CTL activities, indicating that α-IFN may inhibit the induction of CTL, and thereby may be related to the reduction of hepatocyte injury.