Abstract: Agaricus blazei Murill (ABM) is rich in polysaccharides, and has obvious treatment and prevention efficacy for cancers. A bioactive polysaccharide fraction (ABMB3) was isolated from hot water extract of A. blazei fruit bodies and purified by ethanol precipitation, anion-exchange and gel filtration chromatography. Phase-contrast microscopic observations revealed that the size of mouse macrophages was increased after exposure to ABMB3. ABMB3-activated macrophages could secret TNF-α and IL-1β, and produce a large amount of NO in vitro. Meanwhile, the capacity of the cells for phagocytizing latex beads was also significantly increased. Moreover, ABMB-3-induced activation of mouse macrophages in the presence of L929 tumor cells for 48 h could result in an increased percentage of phagocytes target cells when compared with untreated controls. Therefore, ABMB3 alone had no effect on the growth of L929 cells.

Key words: Agaricus blazei Murill (ABM), immunoactivity, macrophage