An extract based on the medicinal mushroom Agaricus blazei Murill stimulates monocyte-derived dendritic cells to cytokine and chemokine production in vitro

The edible mushroom Agaricus blazei Murill (AbM), which has been used in traditional medicine against a range of diseases and possess immunomodulating properties, probably due to its high content of β-glucans. Others and we have demonstrated stimulatory effects of extracts of this mushroom on different immune cells. Dendritic cells are major directors of immune function. We wanted to examine the effect of AbM stimulation on signal substance release from monocyte-derived dendritic cells (MDDC). After 6 d incubation with IL-4 and GM-CSF, the cells were true MDDC. Then the cells were further incubated with up to 10% of the AbM-based extract, AndoSan™, LPS (0.5 μg/ml) or PBS control. We found that the AbM extract promoted dose-dependent increased levels of IL-8, G-CSF, TNFα, IL-1β, IL-6 and MIP-1β, in that order. The synthesis of IL-2, IL-8 and IFNγ were similar for the AbM extract and LPS. However, AndoSan™ induced a 10- to 2-fold higher production than did LPS of G-CSF, TNFα and IL-1β, respectively. AbM did not induce increased synthesis of Th2 or anti-inflammatory cytokines or the Th1 cytokine IL-12. We conclude that stimulation of MDDC with an AbM-based extract resulted in increased production of proinflammatory, chemotactic and some Th1-type cytokines in vitro.