Dr. Brian Coombes and his lab are pursing research to understand the microbes that drive chronic inflammation in Crohn’s disease, with a focus on adherent-invasive E. coli (AIEC). AIEC are more abundant in people with Crohn’s disease, but currently we don’t understand why. What is known is that AIEC can influence disease course in pre-clinical models of Crohn’s disease, which has been the focus of this research. An important contributor to Crohn’s disease is psychological stress, however the reasons why stress can exacerbate symptoms and causes flares is unclear. Dr. Coombes and his team have developed a pre-clinical model in which psychological stress leads to changes in the gut microbiome that are similar to the microbiome of Crohn’s disease patients. This dysbiosis is dominated by the expansion of AIEC and other bacteria in the ileum. They have started to characterize the host immune response to stress that influences AIEC expansion. With this new grant, Dr. Coombes will continue to advance understanding of the immune response and microbial changes imposed by stress that drive microbial imbalance, and pursue strategies to remediate the gut microbiome.