This MAb recognizes the peptide core of gastric mucin M1 (>1,000kDa) (recently identified as Mucin 5AC). Its epitope is destroyed by beta-mercaptoethanol and proteases but not by periodate treatment. Antibody to gastric mucin M1 reacts with the gastric epithelium of normal human gastrointestinal tract as well as with the precancerous and cancerous colon but not with normal adult colon. It also reacts with fetal colonic mucosa. Resurgence of gastric mucin reactivity during colonic carcinogenesis is due to re-expression of the peptide core of gastric (or fetal colonic) mucins.
