title: Calcium-dependent heparin-like ligands for L-selectin in nonlymphoid endothelial cells.
abstract: L-Selectin is a calcium-dependent mammalian lectin that mediates lymphocyte trafficking by recognizing sialylated ligands on high endothelial venules in lymph nodes. Although L-selectin probably mediates neutrophil extravasation into nonlymphoid tissues, no corresponding ligand has been characterized. Staining of cultured endothelial cells with an L-selectin chimera (LS-Rg) showed an internal pool of ligands. Metabolic labeling with sulfur-35-labeled sulfate revealed heparin lyase-sensitive ligands that bound LS-Rg in a calcium-dependent, sialic acid-independent manner. A fraction of commercial heparin bound to LS-Rg and LS-Rg bound to heparin-agarose, both in a calcium-dependent manner. Thus, L-selectin recognizes endothelial heparin-like chains, which could be physiological ligands mediating leucocyte trafficking.
authors.affiliation: Glycobiology Program, UCSD Cancer Center.
authors.forename: K E
authors.initials: KE
authors.lastname: Norgard-Sumnicht
authors.forename: N M
authors.initials: NM
authors.lastname: Varki
authors.forename: A
authors.initials: A
authors.lastname: Varki
mesh_terms: D000818:Animals; D000990:Antithrombin III / Q000378:metabolism; D002118:Calcium / Q000502:physiology*; D002417:Cattle; D015815:Cell Adhesion Molecules / Q000378:metabolism*; D002460:Cell Line; D004591:Electrophoresis, Polyacrylamide Gel; D004729:Endothelium, Lymphatic / Q000378:metabolism; D004730:Endothelium, Vascular / Q000378:metabolism*; D006025:Glycosaminoglycans / Q000378:metabolism*; D006493:Heparin / Q000378:metabolism; D006801:Humans; D019041:L-Selectin; D008024:Ligands; D011485:Protein Binding; D011869:Radioligand Assay; D011993:Recombinant Fusion Proteins / Q000378:metabolism
chemical_list: D015815:Cell Adhesion Molecules; D006025:Glycosaminoglycans; D008024:Ligands; D011993:Recombinant Fusion Proteins; D019041:L-Selectin; D000990:Antithrombin III; D006493:Heparin; D002118:Calcium