IL-35-producing regulatory T cells regulate intestinal inflammatory immune response

Abstract

Objective To evaluate the function of interleukin-35 (IL-35)-producing regulatory T cells (IL-35-Treg) in regulating intestinal inflammatory immune response. Methods The percentages and characteristics of IL-35-Treg in the intestinal lamina propria of transgenic mice expressing IL-35 were analyzed by flow cytometry. A mouse model of inflammatory bowel disease (IBD) was established by giving 1.5% DSS in drinking water. Influences of IL-35-Treg depletion on mouse weight, pathological injury and the secretion of IFN-γ were analyzed. Results IL-35-Treg were enriched in the intestinal lamina propria, and mainly derived from thymic Treg (tTreg). Intestinal IL-35-Treg expressed high levels of programmed death 1 (PD-1). Depletion of IL-35-Treg in mice with DSS-induced IBD resulted in an aggravation through up-regulating the expression of IFN-γ. Conclusion IL-35-Treg might play an important role in the regulation of intestinal inflammatory immune response. Key words: Inflammatory bowel disease; Interleukin-35; Regulatory T cell; Immunoregulation