Anti-integrin αvβ6 antibodies predict pouchitis in patients with ulcerative colitis after restorative proctocolectomy with ileal pouch-anal anastomosis

Abstract

Background Pouchitis is the most common complication of restorative proctocolectomy (RPC) with ileal pouch-anal anastomosis (IPAA) in patients with ulcerative colitis (UC). We previously reported the presence of anti-integrin αvβ6 antibodies in the serum of patients with UC. This study investigated the association between anti-integrin αvβ6 antibodies and the development of pouchitis in patients with UC. Methods Serum levels of anti-integrin αvβ6 antibodies were measured by enzyme-linked immunosorbent assay in 16 patients with UC who underwent RPC with IPAA. Integrin αvβ6 expression in the colonic, terminal ileal, and pouch epithelium was examined using immunohistochemistry and western blot analysis. Results Anti-integrin αvβ6 antibody levels in patients with UC were significantly decreased at 3, 9, and 12 months after RPC (P < 0.05). However, in patients who developed pouchitis, antibody levels remained high. The antibody levels at the time of RPC were significantly higher in patients who developed pouchitis compared to those who did not. Kaplan-Meier analysis revealed a significantly higher incidence of pouchitis in patients with antibody levels above the cutoff at the time of RPC. Although integrin αvβ6 was not expressed in the terminal ileal epithelium at the time of RPC, expression became positive in the pouch epithelium of patients with pouchitis. Conclusions The anti-integrin αvβ6 antibody levels in patients with UC were decreased after RPC, but remained high in patients who developed pouchitis. The antibody levels at the time of RPC may serve as a potential prognostic biomarker for predicting the risk of pouchitis in patients with UC.