immunomedulatory effect of Ganoderma Lucidum polysachharide extract on BALB/c peritoneal macrophage function

Ganoderma Lucidum has been regarded as a natural immunomodulator. The exact carbohydrate epitope responsible for the immunomodulatory activity and its receptor have not been identified, but it seems likely that it is the receptor CR3 [complement receptor 3] which can bind to beta-glucan polysachharide. Because glucose-6-phosphate dehydrogenase [G6PD] activity has a critical role in the regulation of macrophage functions such as nitric oxide [NO] production, we assessed the immunomodulatory effect of GL-PS in BALB/c peritoneal macrophages. For this purpose, BALB/c mice peritoneal macrophages were isolated and treated with various concentrations of GL-PS [0.001, 0.01, 0.1, 1, 10, 100 microg/ml]. After 24 hours, the viability of treated macrophages was measured by MTT assay at 540 nm and the effective dose was determined to be 0.1 microg/ml. Then, macrophages were sonicated and special activity of G6PD was measured in the cell extracts by measuring the alterations in NADPH absorption at 339nm and protein concentration by Bradford method. Also, NO production was determined by use of Griess-reagent after 18 hours. Results of this study showed that 0.1 microg/ ml of GL-PS had the maximal effect on cell viability [stimulation Index] in comparison to other doses [0.05