Abstract: Objective To study the effects of PTD-HBcAg inducing HBV specific cytotoxic T lymphocytes in mice on inhibiting HBV replication in HepG2.2.15 cells. Methods BALB/c mice were subcutaneously immunized at the tail base with 100μl of freshly prepared emulsion containing with PTD-HBcAg,HBcAg,PTD,PBS and an equal volume of CFA. 14days later,T lymphocytes in spleen were isolated and stimulated with corresponding proteins to detect the level of IFN-γ,IL-12,IL-4 and IL-10 in the supernatants. The stimulated T lymphocytes as effective cells were cocultured with HepG2.2.15 cells to determine the levels of HBsAg and HBV DNA and to observe the cytotoxicity of effective cells to HepG2.2.15 cells. Results The cytokines in PTD-HBcAg groups were markedly higher than HBcAg groups and normal controlled groups;In comparison with normal controlled groups and HBcAg groups,HBsAg and HBV DNA decreased more obviously in PTD-HBcAg groups;The T lymphocytes stimulated by PTD-HBcAg could kill HepG2.2.15 cells more effectively than others. Conclusions PTD-HBcAg can highly promote HBV specific CTL to inhibit HBV replication in HepG2.2.15 cells.

Key words: Hepatitis B virus, PTD-HBcAg, Fusion protein, Cytotoxic T lymphocyte, HepG2.2.15 cell line