Cytokine expression and the role of Thl7 cells in mice colitis

To explore the expression and mechanism of Thl7 cells and cytokines in mice model with 2,4,6-trinitrobenzenesulphonic acid (TNBS)-induced inflammatory bowel disease (IBD).

ELISA assay was used to detect the expression of Th17 cytokine IL-17 and Thl cytokines IFN-y in colon tissues. Western blot assay was applied to detect IL-17 expression in peripheral blood mononuclear cells (PBMC), spleen mononuclear cells (SMC), mesenteric lymph node cells and colon tissue of colitic mice. RT-PCR assay was used to detect the effect of anti-IL-17 antibody application on TNF-a, IFN-y and IL-6 mRNA levels in SMCs from colitic mice.

Th17 cytokine IL-17 and Thl cytokines IFN-y were both expressed at high level in TNBS-induced colitic mice. In addition, the expression of Thl7 cytokine appeared earlier than the Thl cytokine. IL-17 levels in SMCs, mesenteric lymph node cells and colon tissue of the disease model group had significant differences compared with normal control group (p<0.01), while the IL-17 level in PBMCs of the disease model group had no significant difference (p>0.05) to control group. After application of 10 ug/mL anti-IL-7 antibody, the TNF-ct, IL-6 and IFN-y mRNA levels in SMCs of the model group showed no significant difference from that of no antibody group (p>0.05).

Both Th17 cells and Thl cells involved in TNBS-induced IBD and the role of Thl17 cells may be through inducing the secretion of pro-inflammatory cytokines.