Helicobacter pylori and neutrophils: Sialic acid-dependent binding to various isolated glycoconjugates

Helicobacter pylori has been shown to agglutinate erythrocytes in a sialic acid-dependent manner. However, very few studies have examined relevant tar get cells in the human stomach. Neutrophils are required for the onset of g astritis, and the inflammatory reaction may be induced on contact between b acteria and neutrophils. In the present work, glycolipids and glycoproteins were isolated from neutrophils and were studied for binding by overlay wit h radiolabeled bacteria on thin-layer chromatograms and on membrane blots. There was a complex pattern of binding bands. The only practical binding ac tivity found was sialic acid dependent, since treatment of glycoconjugates with neuraminidase or mild periodate eliminated binding. As shown before fo r binding to erythrocytes and other glycoconjugates, bacterial cells grown on agar bound to many glycoconjugates, while growth in broth resulted in ba cteria that would bind only to polyglycosylceramides, which are highly hete rogeneous and branched poly-N-acetyllactosamine-containing glycolipids. App roximately seven positive bands were found for glycoproteins, and the tradi tional ganglioside fraction showed a complex, slow-moving interval with ver y strong sialic-acid-dependent binding, probably explained by Fuc substitut ions on GlcNAc.