OBJECTIVETo observe the regulating effect of hepatitis C virus (HCV) envelop (E) 2 gene immunization-induced immune responses by adenovirus mediated interleukin 12 (IL-12).

METHODSHCV E2 protein was expressed and purified from NIH 3T3 and then used as an antigen to detect antibodies against HCV E2. With 51Cr release, SP2/0 expressing HCV E2 was used as target cell to detect specific cytotoxic T lymphocytes (CTL) response; adenovirus recombined IL-12 was propagated by 293 cell. HCV E2 recombinant and adenovirus recombined IL-12 were injected into the quadriceps femoris muscles and abdominal cavities of 6-8 weeks old BALB/C mice. Sera were collected at 2, 3, and 4 weeks and detected for antibodies for E2. Spleen cells isolated at 4 weeks were analyzed for specific CTL response.

RESULTSIt was found that expression of IL-12 at an undetectable level did enhance HCV E2 gene immunization-induced CTL activity and there was no effect on its hormonal immune response.

CONCLUSIONUsing adenovirus to express interleukin 12 was helpful for regulation of HCV E2 gene immunization-induced immune response. Combined HCV E2 and IL-12 can render a strong anti-HCV CTL activity and may be of use in the development of HCV gene vaccine in the future.