Project 467119

The gut microbiota in the gastrointestinal tract is composed of a dense microbial community and makes up the second genetic pool in humans, the microbiome. Notably, the microbiota is necessary for the development and training of the immune system, protection against pathogens and consuming indigestible dietary nutrients. These benefits are dependent on the composition of the microbial community, in which dysbiosis or alterations in the composition is associated to disease states, including but not limited to cancer, obesity, and Parkinsons disease. It is known that there is a causal link between the microbiota composition and patient response to cancer immunotherapy. Specifically, scientists identified bacteria associated with positive treatment response and were able to reinstate cancer immunotherapy response in nonresponse mice after orally administering the bacterial species. Using live therapeutics or probiotics has great potential but can be challenging to colonize the colon with exogenous bacteria. On the other hand, the composition of the endogenous bacterial species making up the microbiota can be shaped through dietary glycans. These chains of carbohydrate molecules are otherwise indigestible by enzymes in the human genome, but bacterial species in the gut can access this energy source and proliferate. In order to use the prebiotic approach with glycans, a more comprehensive understanding of the specific glycan molecules that improve patient response to cancer immunotherapy needs to be identified, as well as the specific bacterial species that benefit from consuming these glycans. This study can improve our understanding of glycan metabolism in the gut microbiota and the mechanisms by which bacteria modulate the immune system response to cancer treatment.