Does Helicobacter pylori affect gastric mucin expression? Relationship between gastric antral mucin expression and H-pylori colonization

Background/objective Helicobacter pylori colonizes the gastric mucous gel l ayer, the surface epithelium and glands, It has been shown that H. pylori i nfection causes aberrant expression of gastric mucins MUC 5 and MUC 6, This study aimed to determine the distribution of MUC 5 and MUC 6 in the gastri c antrum of dyspeptic patients, and to investigate changes in this pattern in the presence of H. pylori and after successful eradication, Materials an d methods Gastric antrum biopsy specimens were examined by immunohistochemi stry for mucin gene (MUC 5 and MUC 6) expression. Polyclonal antibodies wer e used to detect amino acid tandem repeats of each protein. A scoring syste m (0-3) was used to assess staining intensity at three sites: foveola, muco us neck cells and glands. H. pylori status was determined by histology and rapid urease test, and considered positive or negative when both tests were positive or negative, respectively. The study included 49 patients positiv e for H. pylori, in 36 of whom successful eradication was performed, and 11 H. pylori-negative patients. Results There was a gradient of MUC 5 express ion, higher to lower, from the surface to the glands, which was more pronou nced before eradication, Increased MUC 5 synthesis in the mucous neck cells and in the glands was found after H. pylori eradication (P = 0.016). MUC 6 was synthesized in the glands more than in the mucous neck cells or foveol a. MUC 6 was also secreted into the lumen and probably comprised the superf icial part of the unstirred mucous layer. Conclusion The change in MUC 5 sy nthesis may reflect H. pylori colonization. Eur J Gastroenterol Hepafol 13: 19-23 (C) 2001 Lippincott Williams & Wilkins.