P090 Role of TREM2 in the pathogenesis of DSS-induced IBD

Abstract

Introduction Triggering receptor expressed on myeloid cells-2 (TREM-2) is a cell surface receptor that participates in diverse cellular functions including inflammation, bone homeostasis and neurological development. We examined the effects of TREM-2 on experimentally induced inflammatory bowel disease (IBD) in mice. Methods Wild type (WT) and TREM2 transgenic (TREM2 TG) mice were administrated with dextran sulfate sodium (DSS) to induce IBD. The gene expression of proinflammatory cytokines were examined using RT-PCR and histopathological analysis was performed by H&E staining. The population of regulatory T cells was analyzed by flow cytometry. Results We found that body weight and colon length were remarkably decreased by treatment of DSS in TREM2-TG mice compared with WT littermates. Gene expression of proinflammatory cytokines including TNF-a, IL-1b, IL-17F, and IL-6 was increased in colonic tissue of DSS-treated TREM2-TG mice. In addition, recruitment of immune cells into colon tissue was also increased by DSS treatment in TREM2-TG mice, but population of regulatory T cells was decreased. Conclusion Our data suggest that TREM2 may be involved in the pathogenesis of IBD by upregulating proinflammatory cytokines due to the reduction of regulatory T cells.