Accessibility of glycolipid and oligosaccharide epitopes on rabbit villus and follicle-associated epithelium
American Journal of Physiology - Gastrointestinal and Liver Physiology
Mantis, Nicholas J., Andreas Frey, and Marian R. Neutra. Accessibility of glycolipid and oligosaccharide epitopes on rabbit villus and follicle-associated epithelium. Am J Physiol Gastrointest Liver Physiol 278: G915-G923, 2000.-The initial step in many mucosal infections is pathogen attachment to glycoconjugates on the apical surfaces of intestinal epithelial cells. We examined the ability of virussized (120-nm) and bacterium-sized (1-µm) particles to adhere to specific glycolipids and
... olipids and protein-linked oligosaccharides on the apical surfaces of rabbit Peyer's patch villus enterocytes, follicle-associated enterocytes, and M cells. Particles coated with the B subunit of cholera toxin, which binds the ubiquitous glycolipid GM1, were unable to adhere to enterocytes or M cells. This confirms that both the filamentous brush border glycocalyx on enterocytes and the thin glycoprotein coat on M cells can function as size-selective barriers. Oligosaccharides containing terminal ␤(1,4)-linked galactose were accessible to soluble lectin Ricinus communis type I on all epithelial cells but were not accessible to lectin immobilized on beads. Oligosaccharides containing ␣(2,3)linked sialic acid were recognized on all epithelial cells by soluble Maackia amurensis lectin II (Mal II). Mal II coated 120-nm (but not 1-µm) particles adhered to follicle-associated enterocytes and M cells but not to villus enterocytes. The differences in receptor availability observed may explain in part the selective attachment of viruses and bacteria to specific cell types in the intestinal mucosa.