Potent synergistic effect of sho-saiko-to, a herbal medicine, during vaccine therapy in a murine model of hepatitis B virus carrier.

Background: Traditional herbal medicine, sho-saiko-to (TJ-9), improves subjective symptoms, and a recently developed vaccine therapy reduces the viral replication in some chronic hepatitis B virus (HBV)-carriers. The study presented here considers the impact of a combination of vaccine therapy and TJ-9 and the mechanism underlying the therapeutic effect of TJ-9. Materials and methods: HBV-transgenic mice (HBV-Tg) expressing similar levels of HBV-related antigens and HBV DNA were used as an animal model of HBV-carrier state, and were assigned to receive either a TJ-9-enriched diet or a monthly injection of vaccine containing hepatitis B surface antigen (HBsAg), or both, for 12 consecutive months. Results: Twelve months after starting the therapy, 9% (1 of 11), 61% (11 of 18), and 100% (10 of 10) of HBV-Tg receiving only the TJ-9-treatment, only the monthly vaccine, and both the TJ-9 and vaccine, respectively, responded to therapy and became completely negative for HBsAg. Spleen lymphocytes and antigen presenting cells (APC) from TJ-9-treated HBV-Tg produced significantly higher levels of IgM, IgG and antibodies to keyhole limper hemocyanin (KLH) and showed significantly higher stimulatory capacity in allogenic mixed leukocyte reaction (MLR) compared with the spleen cells and APC from HBV-Tg receiving normal diet without TJ-9 (P < 0.05). Conclusion: These data confirm the therapeutic role of TJ-9 during HBV infection and inspire optimism of a widespread use of TJ-9 during immune therapies.