Gastric corpus mucin expression after partial gastrectomy, in relation to colonization with Helicobacter pylori

Twelve different genes for mucin have been described. MUC5AC and MUC6 encod e the secreted apomucins of the stomach. A gradient from the surface epithe lium (foveola) to the glands is typical for MUC5AC synthesis, whereas a gra dient in the opposite direction was found for MUC6. Our goal was to determi ne the distribution of MUC5AC and MUC6 in the postoperative stomach, with r elation to the H. pylori status. Gastric corpus biopsy specimens from patie nts who underwent partial gastrectomy were examined by immunohistochemistry for mucin gene (MUC5AC and MUC6) apoproteins. We used polyclonal antibodie s for amino acid tandem repeats of both proteins. A scoring system (0-3) wa s used to assess staining intensity at four sites: the lumen, the foveola, the mucous neck cells, and the glands. Helicobacter pylori status was deter mined by histology and rapid urease test and was considered positive or neg ative when both tests were positive or negative, respectively. We studied 1 9 H. pylori-positive and 32 H. pylori-negative patients. No significant cha nge in MUC5AC or MUC6 synthesis and secretion was demonstrated between H. p ylori-positive or -negative patients. A gradient similar to that shown for the intact stomach (from the surface epithelium to the glands) for MUC5AC p rotein and an increase of MUC6 protein presentation from the mucous neck ce ll to the glands were demonstrated. The pattern of MUC5AC protein synthesis was not different between H. pylori-positive and -negative patients in the postoperative stomach. MUC6 expression was higher in the foveola in H. pyl ori-positive patients, whereas there was no difference in the other cell la yers.