Inflammatory bowel disease (IBD) is thought to result from a dysregulated mucosal immune response to luminal microbial antigens, with T lymphocytes mediating the colonic pathology. Infection with Helicobacter spp has been reported to cause IBD in immunodeficient mice, some of which lack T lymphocytes. To further understand the role of T cells and microbial antigens in triggering IBD, we infected interleukin (IL)-10−/−, recombinase-activating gene (Rag)1−/−, T-cell receptor (TCR)-α−/−, TCR-β−/−, and wild-type mice with Helicobacter hepaticus or Helicobacter bilis and compared the histopathological IBD phenotype. IL-10−/−mice developed severe diffuse IBD with either H. bilis or H. hepaticus, whereas Rag1−/−, TCR-α−/−, TCR-β−/−, and wild-type mice showed different susceptibilities to Helicobacter spp infection. Proinflammatory cytokine mRNA expression was increased in the colons of Helicobacter-infected IL-10−/−and TCR-α−/−mice with IBD. These results confirm and extend the role of Helicobacter as a useful tool for investigating microbial-induced IBD and show the importance, but not strict dependence, of T cells in the development of bacterial-induced IBD.
Expression of CD45RB functionally distinguishes intestinal T lymphocytes in inflammatory bowel disease