SOD1 and hepatitis B virus infection: For example, Poria cocos polysaccharides (PCP) were found to increase the number of circulating cytotoxic T-lymphocyte [21], improve macrophage phagocytosis, thymus index and spleen index [12], increase serum levels of IgA, IgG, and IgM [22], decrease reactive oxygen species (ROS) and increase SOD [23] and have been used as an adjuvant in the rabies and hepatitis B vaccines [24, 25].