The simple
mucin-type
carbohydrate antigens Tn, sialyl-Tn and T represent the
mucin core
oligosaccharide structures that are produced in the initial steps of
mucin biosynthetic pathway. Utilising
monoclonal antibodies anti-
Tn antigen, anti-
sialyl-Tn antigen and
anti-T antigen, we have investigated the expression of the simple
mucin-type
carbohydrate antigens in 47 biopsy specimens of
antral mucosa with chronic active
gastritis, 25 of which had Helicobacter pylori
infection. The Tn immunoreactivity, localised at the supranuclear region of surface and glandular mucous cells, was observed in all samples, independently from H. pylori status. The
sialyl-Tn antigen, mainly localised in the cytoplasm of glandular mucous cells and in goblet cells vacuoles, was seen in 56% of the cases with H. pylori
infection and in 41% of the cases in the H. pylori-negative group. In addition, the
T antigen was found in the cytoplasm of surface and glandular mucous cells in 16% of the H. pylori-positive group, whereas the percentage of positive cases was reduced to 5% in H. pylori-negative patients, with an exclusive localisation in the cytoplasm of glandular mucous cells; after
neuraminidase treatment, the percentage of
T antigen-positive cases was increased to 28% in H. pylori-positive cases and to 27% in negative cases. No significant relationships between H. pylori
infection and Tn, sialyl-Tn or
T antigen immunoexpression were encountered in our cases. Therefore, we maintain that the inflammatory infiltrate may itself play an important role in the expression of simple
mucin-type
carbohydrate antigens in chronic active
antral gastritis.