Does Helicobacter pylori affect gastric mucin expression? Relationship between gastric antral mucin expression and H. pylori colonization.
OBJECTIVE
Helicobacter pylori colonizes the gastric mucous gel layer, the surface epithelium and glands. It has been shown that H. pylori infection 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 gastric antrum of dyspeptic patients, and to investigate changes in this pattern in the presence of H. pylori and after successful eradication.


METHODS
Gastric antrum biopsy specimens were examined by immunohistochemistry for mucin gene (MUC 5 and MUC 6) expression. Polyclonal antibodies were used to detect amino acid tandem repeats of each protein. A scoring system (0-3) was used to assess staining intensity at three sites: foveola, mucous 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 positive 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 expression, higher to lower, from the surface to the glands, which was more pronounced 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 foveola. MUC 6 was also secreted into the lumen and probably comprised the superficial part of the unstirred mucous layer.


CONCLUSIONS
The change in MUC 5 synthesis may reflect H. pylori colonization.
Morgenstern
S
S
Department of Pathology, Rabin Medical Center, Tel Aviv University, Israel.
Koren
R
R
Moss
S F
SF
Fraser
G
G
Okon
E
E
Niv
Y
Y
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015169:Colony Count, Microbial; D005260:Female; D005752:Gastric Mucins / Q000378:metabolism*; D015870:Gene Expression; D016481:Helicobacter Infections / Q000378:metabolism*; D016480:Helicobacter pylori / Q000254:growth & development; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008875:Middle Aged; D011706:Pyloric Antrum / Q000378:metabolism*
D005752:Gastric Mucins