IL10 and Chronic colitis: Our hypothesis is further supported by a study showing that a nonpathogenic intestinal E. coli isolate as well as the pathogen Salmonella typhimurium were able to outcompete the endogenous microbiota of IL-10−/− mice, a murine model of chronic colitis, suggesting that growth of Gram-negative enterobacteria is enhanced by host mediated intestinal inflammation and following modification of the composition of intestinal microbiota [30, 31].