Helicobacter hepaticus does not induce or potentiate colitis in interleukin-10-deficient mice

Helicobacter hepaticus has been reported to induce colitis, hepatitis, and hepatocellular carcinoma in several different murine models. The aim of thi s study was to determine if H. hepaticus will cause colitis in monoassociat ed mice lacking the interleukin-10 gene (IL-10(-/-) mice) and potentiate co litis in specific-pathogen-free (SPF) IL-10(-/-) mice. Germfree IL-10(-/-) mice on either a mixed (C57BL/6 x 129/Ola) or inbred (129/SvEv) genetic bac kground were monoassociated with H. hepaticus ATCC 51448 by oral feeding an d rectal enemas. In a second experiment, germfree IL-10(-/-) mice were colo nized with stool from SPF mice that harbored or did not harbor endogenous H . hepaticus. After 7 to 9 weeks of colonization, weight loss and mortality were assessed, the colon was isolated for histology and IL-12 secretion, an d mesenteric lymph node cells were assessed for T-cell activation markers. It was found that IL-10(-/-) mice monoassociated with H. hepaticus for up t o 16 weeks show ed almost no histologic colitis or increased IL-12 producti on. SPF IL-10-knockout mice had no significant difference in weight loss, m ortality rate, histologic scores, colonic IL-12 secretion, or T-cell activa tion with or without H. hepaticus. We conclude that H. hepaticus does not i nduce or potentiate disease in our IL-10(-/-) mice and therefore is not req uired to induce colitis in genetically susceptible hosts.