Submitted to: Journal of Nutrition
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/3/2007
Publication Date: 5/18/2007
Citation: Wu, D., Pae, M., Ren, Z., Guo, Z., Smith, D., Meydani, S. 2007. Dietary Supplementation with White Button Mushroom Enhances Natural Killer Cell Activity in C57BL/6 Mice. Journal of Nutrition. 137(6): 1472-1477.
Interpretive Summary: The function of the immune system is critical to preventing and controlling infections and cancers. Good nutritional planning that involves intake of essential nutrients and functional foods have become a favored approach to support immune cell function. Mushrooms have long been suggested to ward off disease and maintain health and to possess the ability to stimulate the immune system, but scientific data supporting their health benefits are limited, especially the white button mushrooms (Agaricus bisporus), which constitutes 90% of mushrooms consumed in the US. Therefore, the objective of this study was to determine the effect of white button mushrooms on innate and T cell-mediated immune functions. In this study, we fed mice a diet white button mushroom powder for 10 weeks and examined response of their immune cells. Results showed that white button mushroom powder supplementation enhanced natural killer (NK) cell activity and other immune responses except for the cells formed in the spleen and did not effect on macrophage production. White button mushroom did tend to enhance T cell and B cell growth but these differences did not reach statistical significance. These results suggest that increased intake of WBM may boost natural immunity against tumors and viruses by stimulating killer cell activity. The study shows that diet supplementation with white button mushrooms enhances natural killer cell activity and cytokines, which are hormone-like proteins that affect the immune system’s response. Natural killer cells and cytokines play an important part in defending the body against tumors and viral infections, both important widespread public health issues. These results suggest that consumption of white button mushrooms may increase the natural immune response against tumors and viral infections.
Technical Abstract: Mushrooms have been shown to possess anti-tumor, anti-viral, and anti-bacterial properties. These effects of mushrooms are suggested to be due to their ability to modulate immune cell functions. However, majority of these studies evaluated the effect of administering extracts of exotic mushrooms through parental routes while little is known about the effect of dietary intake of white button mushrooms (WBM), which represent 90 percent of mushrooms consumed in the US, on immune function. In this study, we fed C57BL/6 mice a diet containing 0, 2, or 10 percent (w/w) WBM powder for 10 weeks and examined indices of innate and cell-mediated immunity. Results showed that WBM supplementation dose-dependently enhanced natural killer (NK) cell activity, interferon-gamma (IFN-gamma) and TNF-alpha production, and tended to increase interleukin (IL)-2 production but had no effect on IL-10 production by splenocytes. There was a significant correlation between NK activity and IFN-gamma production. WBM had no significant effect on macrophage production of IL-6, TNF-alpha, prostaglandin E2, nitric oxide, and H2O2, nor did it affect the percentage of total T cells, helper T cells (CD4+), cytotoxic/suppressive T cells (CD8+), regulatory T cells (CD4+/CD25+), total B cells, macrophages, and NK cells in spleens. WBM tended to dose-dependently enhance T cell and B cell proliferation but these differences did not reach statistical significance. These results suggest that increased intake of WBM may promote innate immunity against tumors and viruses through enhancement of a key component, NK activity. This effect of WBM might be mediated through increased INF-gamma'production.