In Crohn's Disease, Anti-TNF-α Treatment Changes the Balance between Mucosal IL-17, FOXP3, and CD4 Cells

Abstract EN

Aim.

In Crohn's disease (CD), anti-TNF-α treatment is a potent medication.

We aimed to characterize the effect of anti-TNF-α treatment on T effector and regulatory cells.

Material and Methods.

We studied T-effector and regulatory cells on cellular and mRNA levels in intestinal biopsy samples from 13 Crohn's disease patient.

Biopsies were obtained at baseline and 3 months after anti-TNF-α treatment, and from 14 inflammation-free control subjects.

Results.

Patients had higher numbers of ileal IL-17+ and forkhead box P3 (FOXP3)+ cells than did control subjects, both before ( P≤0.001 and P≤0.05, resp.) and after the anti-TNF-α treatment (P≤0.01, P≤0.01).

Intestinal interferon-γ and IL-17 mRNA expression was higher in Crohn's disease and remained elevated after anti-TNF-α treatment.

The ratio of IL-17+ cells to CD4+ cells decreased (P≤0.05) and compared to baseline the ratio of IL-17+ cells to FOXP3+ was lower after treatment (P≤0.05).

Conclusions.

TNF-α-blocking agents improved intestinal balance between IL-17+ T-effector and regulatory T cells, although intestinal IL-17 upregulation remained elevated.