Atractylodis macrocephalae Koidz. polysaccharides enhance both serum IgG response and gut mucosal immunity

► Atractylodis macrocephalae Koidz. polysaccharide (RAMPS) is an oral adjuvant. ► Oral administration of RAMPS enhances gut mucosal immunity in mice. ► Serum specific IgG response is high in mice with enhanced gut mucosal immunity by RAMPS. ► Serum specific IgG response is low in mice without enhanced gut mucosal immunity. ► RAMPS-enhanced serum IgG response is associated with enhanced gut mucosal immunity.