Mucosal gene signatures to predict response to infliximab in patients with ulcerative colitis

Infliximab, an anti-TNF-alpha monoclonal antibody, is an effective treatment for ulcerative colitis (UC) with over 60% of patients responding to treatment and up to 30% reaching remission. The mechanism of resistance to anti-TNF-alpha is unknown. This study used colonic mucosal gene expression to provide a predictive response signature for infliximab treatment in UC. Keywords: drug response Twenty-four patients with active UC, refractory to corticosteroids and/or immunosuppression, underwent colonoscopy with biopsies from diseased colon within a week prior to the first intravenous infusion of 5 mg infliximab per kg body weight. Response to infliximab was defined as endoscopic and histologic healing at 4-6 weeks after first infliximab treatment. Six control patients with normal colonoscopy were included. Total RNA was isolated from colonic mucosal biopsies, labelled and hybridized to Affymetrix Human Genome U133 Plus 2.0 Arrays.