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

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.

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.

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.

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.