CES1 and inflammatory bowel disease: The mouse genome contains a larger number of CES proteins (20 have been annotated) due to tandem gene duplication.16 Of these, CES1d, CES1f, CES1g, CES2a, CES2b, CES2c, and CES2e have known TG hydrolase activity.16–18 Expression of CES2 in the human intestine is well documented.19,20 To delineate whether CES1 protein is expressed in human intestine, we performed western blot of human small bowel epithelial cell lysates prepared from intestinal resections of patients with inflammatory bowel disease.