Potentiation of intestinal immunity by micellary mushroom extracts.

Mushroom (shiitake) extracts were dispersed with lecithin micelles to prepare superfine particles (0.05 to 0.2 microm in diameter) of beta-1,3-glucan (micellary mushroom extracts). When mice were fed with these micelles of beta-glucan (0.75 mg/day/mouse, smaller amounts of beta-glucan), the number of lymphocytes yielded by the small intestine increased by up to 40%. More interestingly, the ratio of CD8alphabeta(+)TCRalphabeta(+) cells/CD8alphaalpha(+)TCRalphabeta(+) cells increased prominently. In parallel with this deviation in the distribution of lymphocyte subsets, tumor cytotoxicity against P815 cells and cytokine productions were also augmented. In other words, phylogenetically developed lymphocytes (CD8alphabeta(+), TCRalphabeta(+)) were much more effectively activated by the oral administration of micellary beta-glucan. These results suggest that smaller amounts of micellary beta-glucan might be useful for the potentiation of intestinal immunity.