Immunomodulatory activities of mushroom sclerotial polysaccharides

The fight against cancer cells in the human body involves a defense system that is comprised of the innate and adaptive immunities which is controlled by a series of immune responses mediated by different immune cells and their secretory substances including cytokines and chemokines. Polysaccharides, especially those of fungal origin are well-known immunopotentiators that can boost up the immune system. Polysaccharides isolated from the fruit bodies and mycelia of both medicinal and edible mushrooms have been found to exert immunomodulatory function and antitumor activity in numerous in vivo and in vitro studies. In contrast, the potential of polysaccharides isolated from mushroom sclerotia as immunomodulators is only emerging. This paper gives a mini review on how the immunomodulatory actions of mushroom polysaccharides can eradicate tumor cells and also includes a recent study on the activation of innate immune cells and T-helper cells in normal and athymic BALB/c mice by three mushroom sclerotial polysaccharides with different structural characteristics extracted from Pleurotus tuber-regium and Polyporus rhinocerus.