Regulation of RAW 264.7 cell-mediated immunity by polysaccharides from Agaricus blazei Murill via the MAPK signal transduction pathway

Agaricus blazei Murill (ABM) is a common anticancer folk remedy. Its active ingredients, i.e. , polysaccharides, have been isolated and exhibit indirect tumor-suppressing activity via immunological activation. The effects of polysaccharides derived from A. blazei Murill (ABMP) on RAW 264.7 cells were examined by western blotting and real-time reverse transcription polymerase chain reaction (RT-PCR). The effects of 500, 1000, and 2000 μg mL −1 ABMP on the growth of RAW 264.7 cells were evaluated by measuring the OD 490 value; the optimum concentration was found to be 1000 μg mL −1 . Based on the RT-PCR results, the expression levels of JNK , ERK , and p38 decreased substantially in lipopolysaccharide (LPS)-induced RAW 264.7 cells treated with ABMP. In RAW 264.7 cells treated with LPS, the protein expression levels of JNK , ERK , and p38 were decreased, as were the levels of phosphorylated JNK , ERK , and p38 . These results indicate that the MAPK signal transduction pathway is a potential mechanism by which ABMP regulates the cell-mediated immunity of RAW 264.7 cells. Agaricus blazei Murill (ABM) is a common anticancer folk remedy.