Adjuvant effect of Atractylodis macrocephalae Koidz. polysaccharides on the immune response to foot-and-mouth disease vaccine

Present study was designed to investigate the polysaccharide (RAMPS) extracted from the rhizome of Atractylodis macrocephalae Koidz. (RAM) for its effect on the immune responses to foot-and-mouth (FMD) vaccine. Thirty-five ICR mice were randomly distributed into 5 groups with 7 mice in each. After oral administration of RAMPS for 4 days at a dose of 0, 0.025, 0.05, 0.1 g or 0.25 g of RAM, respectively, the animals were immunized twice with FMD vaccine at 2-week intervals. Three weeks later, serum IgG, IFN-γ/IL-5, splenocyte proliferation, and mRNA expression of cytokines by splenocytes were measured. Results indicated that RAMPS and RAM significantly enhanced IgG titers, IgG subclasses, IFN-γ, IL-5 and the splenocyte proliferations stimulated by concanavalin A, lipopolysacharide, and FMDV (P < 0.05). Therefore, RAMPS and RAM increased both cellular and humoral immune responses to vaccination, and may have a potential as an oral adjuvant to improve vaccination.