| Diet-induced changes in the structure of bacterial metabolites produced by the human gut symbiotic bacterium Bacteroides fragilis affect host immune regulation, according to a new study led by researchers from Harvard Medical School and Brigham and Womens Hospital in Boston and Monash University in Clayton, Victoria, Australia. This study, which was partially funded by the National Center for Complementary and Integrative Health, was recently published in Nature. Microbial metabolites produced by gut microbes play critical roles in host immune development and health, but little is known about the exact mechanisms responsible for these effects. This study, which was conducted in mice, investigated the effects of a group of lipids known as sphingolipids produced by B. fragilis on the functioning of colonic natural killer T (NKT) cells, which are important in defense and immunity, and the effects of diet on the lipids structure and function. | 