Sialylation of the B lymphocyte molecule CD22 by alpha 2,6-sialyltransferase is implicated in the regulation of CD22-mediated adhesion.

摘要: The B cell surface receptor CD22 binds several sialoglycoproteins containing sialic acid in alpha 2,6 linkage, on the of and T lymphocytes. Because lymphocytes adhere tightly to fibroblasts transfected with cDNA, it would appear reasonable suggest that regulatory mechanisms might have evolved which prevent undesired CD22-mediated leukocyte aggregation. Here we provide evidence for existence at least one mechanism regulate interaction ligands adjacent cells. We demonstrate sialylation by beta-galactoside 2,6-sialyltransferase abrogates lymphocyte adhesion, adhesion can be restored removal 2,6-linked residues from molecule. Taken together, our results both promote inhibit CD22-ligand interactions. These observations first direct receptor-ligand interactions mediated an Ig superfamily molecule are under control a specific glycosyltransferase.