Antiproliferative and immunostimulatory protein fraction from edible mushrooms

Fruit bodies and mycelia of various higher Basidiomycetes were studied in search of biological effector molecules. In this study, we evaluated the antiproliferative and immunomodulatory properties of a protein fraction designated as Cibacron blue affinity eluted protein (CBAEP) isolated from five different species of edible mushrooms (Termitomyces clypeatus, Pleurotus florida, Calocybe indica, Astraeus hygrometricus, and Volvariella volvacea). This protein fraction (10–100 μg/ml) mediated antiproliferative activity on several tumor cell lines through the induction of apoptosis. Also the isolated protein fraction from all five mushrooms had a stimulatory effect on splenocytes, thymocytes and bone marrow cells. Further it enhanced mouse natural killer (NK) cell cytotoxicity and stimulated macrophages to produce nitric oxide (NO). The highest immunostimulatory activity was determined in the CBAEP from T. clypeatus and the highest antiproliferative activity from C. indica.