The improvement of the immune system has been indicated as the main reason of the anticancer effects of Maitake extracts, which potentiated the action of immune cells including macrophages, natural killer (NK) cells and cytotoxic T-cells that may attack carcinogenic cells.

Maitake's polysaccharide may be slightly different from the beta-glucans found in other fungi. The large molecular weight of the polysaccharide molecule and branch structure configurations may be important for its antitumor or immunostimulant effect. Ultimately, polysaccharides from the maitake mushroom act as immune system regulators.

Immunomodulation is the process of enhancing, stabilizing, or depressing the immune system depending on circumstances.  For example, stimulating the immune system is necessary in instances of viral or bacterial infection.  Depressing the immune system may be desirable when experiencing the effects of autoimmune diseases.  Beta-glucans from maitake mushrooms have been shown to play a key role in the immunomodulatory process.

in-vitro Study: Short-term oral application of natural immunomodulating glucans from Maitake mushrooms strongly stimulated both the cellular and humoral branch of immune reactions. (1)

in-vivo Study: Another promising study examined the effect of the MD-fraction from the maitake mushroom on cisplatin-induced myelosuppression in a mouse model. Mice given 8 mg/kg/d while treated with cisplatin did not experience a decrease in NK cells, DCs, and macrophages. These mice also maintained body weight and spleen weight compared to those treated with cisplatin alone (a drug commonly used to interfere with the growth of cancer cells). (2)

Clinical Study: In a phase I/II dose escalation trial, 34 postmenopausal breast cancer patients, free of disease after initial treatment, were enrolled sequentially in five cohorts. Maitake liquid extract was taken orally at 0.1, 0.5, 1.5, 3, or 5 mg/kg twice daily for 3 weeks. There was a statistically significant association between Maitake and immunologic function (p < 0.0005), concluding oral administration of Maitake mushroom is associated with both immunologically stimulatory and inhibitory measurable effects in peripheral blood. (3)


1. Vetvicka V, Vetvickova J. Immune-enhancing effects of Maitake (Grifola frondosa) and Shiitake (Lentinula edodes) extracts. Ann Transl Med. 2014;2(2):14. doi:10.3978/j.issn.2305-5839.2014.01.05