Compound Chinese herbal medicinal ingredients can enhance immune response and efficacy of RHD vaccine in rabbit

In order to validate the immune-enhancement efficacy of compound Chinese herbal medicinal ingredients (cCHMIs), made with astragalus polysaccharide (APS), epimedium polysaccharide (EPS), propolis flavone (PF) and ginsenosides (GS), as immune potentiator or vaccine adjuvants for rabbits, the effects of two cCHMIs on rabbit lymphocyte proliferation and IFN-γ and IL-10 mRNA expression of T lymphocyte in vitro were determined. At the same time, two cCHMIs were injected into 35-day-old rabbits after mixed with rabbit hemorrhagic disease (RHD) vaccine taking aluminum adjuvant and phosphate-buffered saline (PBS) as controls. On days 7, 14, 21, 35 and 49 after the vaccination, the dynamic changes of peripheral lymphocyte proliferation and serum antibody titers of the rabbits were analyzed. On day 63, all rabbits were challenged with RHD virus. The results showed that the two cCHMIs could significantly promote rabbit lymphocyte proliferation and IFN-γ and IL-10 mRNA expression of T lymphocyte in vitro. In vivo, two cCHMIs could significantly enhance serum antibody titers and lymphocyte proliferation. Their adjuvanticity was slightly superior to aluminum adjuvant. All the rabbits vaccinated with the cCHMIs adjuvant vaccine were protected. These findings confirmed that two cCHMIs possessed better immune-enhancement efficacy and would be used as effective immune adjuvant of RHD vaccine.