Adjuvant activity of PCP-II, a polysaccharide from Poria cocos, on a whole killed rabies vaccine.

•Polysaccharide PCP-II was first used as adjuvant in rabies vaccine.•PCP-2 could induce rapid and high antibody responses in mice and dogs.•PCP-II could activate lymphocytes and promote cytokines secretion in mice.•PCP-II is a good candidate for adjuvant on inactivated rabies vaccine for animal and human use.