Although this mucin is predominantly found in airway and stomach mucus,42,45 studies on patients with ulcerative colitis and adenocarcinomas have shown MUC5AC expression in the intestine along with MUC2.31,46 However, this is the first time that Muc5ac expression has been implicated in response to an enteric parasitic infection. This evidence concerns the gene MUC5AC and ulcerative colitis.