Submitted to: Journal of Nutrition
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/1/2008
Publication Date: 2/15/2008
Citation: Ren, Z., Guo, Z., Meydani, S., Wu, D. 2008. White button mushroom enhances maturation of bone marrow derived dendritic cells and their antigen presenting function in mice. Journal of Nutrition. 138:544-550.
Interpretive Summary: Medicinal use of mushrooms has a long history. One of their health benefits is their anti-cancer ability to inhibit tumor growth. This effect is theorized as an ability to help the immune system to respond to cancer cells. Most studies focus on exotic mushrooms. The white button mushroom (WBM), which equals about 90 percent of mushrooms consumed in the United States, has had only a few studies done to learn about their health benefits including how they affect the immune response. Our study using cells from mice showed that supplementing their diet with WBM improved natural killer cell activity. We observed an increase in T cells compared those fed a control diet. We specifically focused on dendritic cells (DC), which are the strongest antigen presenting cells. This means that they are cells capable of recognizing, processing and marking foreign micro-organisms so that the T cells will respond. Our study showed that WBM assist in the growth of these important dendritic cells. Mushroom treated dendritic cells are more effective in activating specific T cells to respond. This effect implies that mushrooms induce the immune system to work against tumor development, an important finding if we are to continue to pursue nutritional methods of fighting and preventing cancer.
Technical Abstract: Mushrooms have been shown to enhance immune response, which contributes to their anti-tumor property. White button mushrooms (Agaricus bisporus) (WBM) constitute 90 percent of the total mushrooms consumed in the United States; however, the health benefit of this strain in general is not well studied. Furthermore, little is known about its immunologic effects. Dendritic cells (DC) are the most potent antigen presenting cells and play a pivotal role in immune response by linking innate and adaptive immune responses. In this study we investigated the effect of in vitro supplementation with WBM on maturation of bone marrow-derived DC (BMDC) of C57BL mice. BMDC were differentiated in the presence of whole mushroom concentrate at 50, 100, or 200 micrograms/ml. Results showed that mushroom supplementation dose-dependently increased the expression of maturation markers CD40, CD80, CD86 and MHC-II as indicated by both the frequency of cells positive for the above markers and their intensity per cell. Consistent with the changes in the phenotypic makers, functional assay for DC maturation showed that mushroom supplementation decreased DC endocytosis and increased intracellular IL-12 levels. Furthermore, using an allogeneic T cell activation model we found that DC supplemented with WBM presented ovalbumin antigen to T cells more efficiently as demonstrated by an increased T cell proliferation and IL-2 production. In conclusion, WBM promote DC maturation and enhance their antigen-presenting function. This effect may have a potential in enhancing both innate and T cell-mediated immunity leading to a more efficient surveillance and defense mechanism against microbial invasion and tumor development.