%0 Journal Article %A Minato, Ken-ichiro %D 2008 %I Begell House %N 3 %P 235-244 %R 10.1615/IntJMedMushr.v10.i3.40 %T Immunomodulation Activity of a Polysaccharide Fraction of a Culinary-Medicinal Mushroom, Pleurotus citrinopileatus Singer (Agaricomycetideae), in Vitro %U https://www.dl.begellhouse.com/journals/708ae68d64b17c52,1b05160a735f1b4e,5b9bfcd91fbccbd1.html %V 10 %X The hot water soluble extract of Pleurotus citrinopileatus (HWE-P) induced high expression of mRNA of tumor necrosis factor (TNF)-α, which is a proinflammatory cytokine, in the stimulated murine macrophage RAW264. However, unlike lipopolysaccharides (LPS), the extract did not induce the expression of mRNA in other cytokines, such as in IL-12 and IL-10. TNF-α production, which was induced from RAW264 stimulated with HWE-P (1 mg·mL−1), was approximately 400 pg·mL−1. These findings showed that the fruiting body of P. citrinopileatus stimulated an early immunological response of a murine macrophage. Furthermore, we chromatographically separated and purified an active fraction from the crude extract of P. citrinopileatus and measured its immunomodulating activity in cytokine production from the stimulated macrophages. This crude extract was separated into six fractions (HWE-P-I, II, III, IV, V, and VI) by anion exchange chromatography using DEAE-Sepharose gel. Then it was found that the HWE-P-IV fraction, which possessed a molecular mass approximately 450 kDa, showed the strongest immunomodulating activity in TNF-α production (4.9 ng·mL−1) from the macrophages. This fraction was mainly composed of a sugar. Moreover, production of nitric oxide (NO) was detected in the macrophages stimulated with this fraction. The amount of NO produced from stimulated RAW264 was 33.8 μM. These results indicate that a polysaccharide fraction from P. citrinopileatus possesses a potent immunomodulating activity. Thus, this culinary-medicinal species could become an effective component of a functional food. %8 2008-07-15