A New Immunostimulatory Proteoglycan-GLIS from Ganoderma lucidum

摘要

A bioactive fraction (GLIS) was isolated from the fruiting body of the fungus Ganoderma lucidum using successive chromatographic steps. GLIS is a proteoglycan and has a carbohydrate: protein in a ratio of 11.5:1. The carbohydrate portion is composed of seven different monosaccharides, predominantly D- galactose. D-glucose and D-mannose in the molar ratio of 1:3.8:1. GLIS stimulated the proliferation of normal mouse and tumor bearing mouse spleen lymphocytes. The proliferation by the factor 4.0 in MSL and the factor 2.5 in MSB. By analysis of flow cytometry and immunofluorescence microscope. it was found that the B cells were enlarged and expressed CD71 and CD25 on the cell surface, this mean that GLIS activated mouse spleen lymphocytes. In addition most of the activated cells were found to be B cells by double staining with CD19/CD25 and CD19/CD71. Lymphocytes also showed a significantly increased production of IL-2. whereas the secretion of IL-4 Was not influenced by GLIS. Furthermore, GLIS did not influence the intracellular Ca<'2+> concentration of lymphocytes, but it enhanced the expression of protein kinase C α and protein kinase C γ in B cells. According to our results GLIS is a new B cell-stimulating factor.