[Immune response to HBsAg can not be enhanced with B7-H1 protein vaccine].

Aim: To observe the immunization effect to HBsAg by B7-H1 protein vaccine in transgenic mice, and to explore new methods for the treatment of chronic hepatitis B.

Methods: After the joint immunization in HBV transgenic mice with different doses of hepatitis B virus (HBV) vaccine and B7-H1 protein, the anti-B7-H1 antibody titors, Th1 type of cytokines (IFN-γ and IL-2) from the spleen cells of mice, the number of the T cells secreting IFN-γ and the number of the mice lymphocyte proliferation were measrued by ELISA, ELISPOT and MTT technique respectively, to compare the immune effect of different immune methods and regimen.

Results: The immune plans were completed successfully. The anti-B7-H1 antibody was detected in the fifth week after immunization with B7-H1 vaccine, at the same time no obvious difference of antibodies titors between groups were found. IL-2 and the number of T cells secreting IFN-γ were significantly reduced(P<0.05)in joint immunization group with B7-H1 protein and HBsAg, but no difference in other immune tests, such as IFN-γ, lymphocyte proliferation.

Conclusion: A lower doses of HBsAg can cause the secretion of Th1 type of cytokines and lymphocyte proliferation. B7-H1 protein vaccines have a better immunogetic effect for HBV transgenic mice, but can notupregulate the immune response to HBsAg.