The MUC5AC glycoprotein is the primary receptor for Helicobacter pylori in the human stomach

• Background and objectives. Helicobacter pylori shows a characteristic tropism for the mucusproducing gastric epithelium. In infected patients, H. pylori colocalizes in situ with the gastric secretory mucin MUC5AC. The carbohydrate blood-group antigen Lewis B (LeB) was deemed responsible for the adherence of H. pylori to the gastric surface epithelium. We sought to determine if MUC5AC is the carrier of LeB, and thus if MUC5AC is the underlying gene product functioning as the main receptor for H. pylori in the stomach. Methods. We studied three types of human tissue producing MUC5AC: Barrett’s esophagus (BE), normal gastric tissue, and gastric metaplasia of the duodenum (GMD). Tissue sections were immunofluorescently stained for MUC5AC or LeB, and subsequently incubated with one of three strains of Texas red-labeled H. pylori , one of which was unable to bind to LeB. We determined the colocalization of MUC5AC or LeB with adherent H. pylori. Results. The binding patterns for the two LeBbinding strains to all tissues were similar, whereas the strain unable to bind to LeB did not bind to any of the tissues. In normal gastric tissue, the LeBbinding strains always bound to MUC5AC- and LeBpositive epithelial cells. In four nonsecretor patients, colocalization of the LeB-binding strains was found to MUC5AC-positive gastric epithelial cells. In BE, the LeB-binding H. pylori strains colocalized very specifically to MUC5AC-positive cells. MUC5ACproducing cells in GMD contained LeB. Yet, LeBbinding H. pylori not only colocalized to MUC5AC or LeB present in GMD, but also bound to the LeBpositive brush border of normal duodenal epithelium. Conclusions. Mucin MUC5AC is the most important carrier of the LeB carbohydrate structure in normal gastric tissue and forms the major receptor for H. pylori.

Subject headings

MEDICIN OCH HÄLSOVETENSKAP  -- Klinisk medicin -- Odontologi (hsv//swe)

MEDICAL AND HEALTH SCIENCES  -- Clinical Medicine -- Dentistry (hsv//eng)

Keyword

adhesion

helicobacter pylori

mucin

MUC5AC

Barrett’s esophagus

gastric metaplasia

Lewis B blood group antigen

ODONTOLOGY

ODONTOLOGI

Publication and Content Type

ref (subject category)

art (subject category)