SULFATED GLYCANS ON ORAL MUCIN AS RECEPTORS FOR HELICOBACTER-PYLORI

Helicobacterpylori is able to colonize gastric epithelia, causing chro nic active gastritis, gastric and duodenal ulcers and presumably gastr ic malignancies, Attempts to identify the natural reservoir for this m icroorganism other than the stomach have been unsuccessful. It is susp ected that H. pylori can be transmitted orally, since the microorganis m has been detected at various sites of the oral cavity. The aim of th e present study was to determine whether H. pylori can bind to salivar y mucins, which in vivo coat the oral epithelia, and characterize furt her the interaction, Binding of salivary mucins and of synthetic oligo saccharides was studied in ELISA and immunoblotting, using specific mo no- and polyclonal antibodies, and synthetic neoglycoconjugates. H. py lori bound most avidly to a highly sulfated subpopulation of high mole cular weight salivary mucins, secreted from the palatine salivary glan ds, and with less avidity to mucin species secreted by the sublingual and submandibular salivary glands, which are less sulfated, Binding wa s strongly enhanced upon decreasing pH from 6.0 to 5.0. Using syntheti c polyacrylamide coupled oligosaccharides it was found that SO3-3-Gal and the SO2-3-Lewis(a) blood group antigen bound to H. pylori. In cont rast, binding of sialylated Lewis(a) and Lewis(b) antigens was much we aker, This study indicates that sulfated oligosaccharides on salivary mucins may provide receptor structures for adhesion of H. pylori to or al surfaces.