Furthermore, animal studies related to colitis have demonstrated that several strains of Bacteroides, including Bacteroides fragilis NCTC 9343, Bacteroides thetaiotaomicron DSM 2079, and Bacteroides cellulosilyticus DSM 14838, can expand the population of interleukin- (IL-) 10-producing CD4+CD45RBlow T cells [8], ameliorate the histopathological damage of the gut [9], and increase the levels of anti-inflammatory IL-10 and Treg cells [10]. The gene discussed is IL10; the disease is colitis.