The Immunostimulatory and Anti-tumor Activities of Polysaccharide from <i>Agaricus bisporus</i> (brown)

Agaricus bisporus is one of the most consumed culinary mushrooms in the world. The white type of Agaricus bisporus has been demonstrated with various bioactivities beneficial to human health. However, little was known about its brown type. In this study, the anti-cancer and immunoregulatory potential of Agaricus bisporus (brown) polysaccharide were investigated in vitro and in vivo. In vitro, the polysaccharide had a significant antiproliferative effect on Hela cells (cervical cancer cells), especially at the high concentration of 200 μg/ml. The spleen index, thymus index and carbon clearance ability of mice were remarkably increased by the polysaccharide treatment, indicating the polysaccharide had a promising benefit for immunodulation in vivo. Furthermore, the polysaccharide increased the proliferation of RAW264.7 cells with 19.1% at 50µg /ml and 34.5% at 100µg /ml, which demonstrated the immunodulation mechanism was in close conjunction with macrophages. In conclusion, these results indicated that Agaricus bisporus (brown) polysaccharide possessed strong immunostimulatory and anti-tumor bioactivity in vivo and in vitro. Therefore, it could be explored as a novel natural antitumor agent with immunomodulatory activity.