Regulatory T cells in Crohn's disease following anti‐TNF‐α therapy

BACKGROUND AND AIM: Anti‐tumor necrosis factor alpha (TNF‐α) therapy is an effective therapy for Crohn's disease (CD). We investigated FoxP3(+) and CD127(−) regulatory T cells (Tregs) before and after administration of anti‐TNF‐α therapy in CD. METHODS: Eight patients with active CD who had received anti‐TNF‐α antibodies were enrolled. Treatment responses were followed by physical examination and Crohn's disease activity index (CDAI) scoring before and 2 weeks after the initial administration of anti‐TNF‐α antibodies. Peripheral blood samples were collected before and 2 weeks after treatment. White blood cell count and serum levels of C‐reactive protein (CRP) and albumin were measured. FoxP3(+) expression and CD127(−) Tregs were measured by fluorescence activated cell sorting (FACS) analysis of whole blood samples. RESULTS: Median values of CDAI decreased significantly after treatment. The proportion of FoxP3(+) Tregs increased significantly after treatment. There was a significant negative correlation between ΔCD127(−) Tregs and Δlymphocyte. CONCLUSIONS: Anti‐TNF‐α therapy would enhance Tregs, which may account for the mechanism underlying the positive effect of the anti‐TNF‐α treatment in CD patients.