title: P-selectin and E-selectin. Distinct but overlapping leukocyte ligand specificities.
abstract: P-selectin on platelets and endothelial cells and E-selectin on endothelial cells are leukocyte receptors that recognize lineage-specific carbohydrates on neutrophils and monocytes. The proposed ligands for these receptors contain the Le(x) core and sialic acid. Since other investigators have shown that both E-selectin and P-selectin bind to sialylated Le(x), we evaluated whether E-selectin and P-selectin recognize the same counter-receptor on leukocytes. The interaction of HL60 cells with Chinese hamster ovary (CHO) cells expressing P-selectin or E-selectin was studied. To determine whether a protein component is required in addition to sialyl Le(x) for either P-selectin or E-selectin recognition, HL60 cells or neutrophils were digested with proteases, including chymotrypsin, elastase, proteinase Glu-C, ficin, papain, or thermolysin. Cells treated with these proteases bound E-selectin but not P-selectin. Fucosidase or neuraminidase treatment of HL60 cells markedly decreased binding to both E-selectin- and P-selectin-expressing CHO cells. Growth of HL60 cells in tunicamycin inhibited the ability of these cells to support P-selectin-mediated binding and, to a lesser extent, E-selectin-mediated binding. Purified P-selectin inhibited CHO:P-selectin binding to HL60 cells, but incompletely inhibited CHO:E-selectin binding to HL60 cells. However, purified soluble E-selectin inhibited CHO:P-selectin and CHO:E-selectin binding to HL60 cells equivalently and completely. COS cells, unable to bind to E-selectin or P-selectin, bound E-selectin but not P-selectin upon transfection with alpha-1,3-fucosyltransferase or alpha-1,3/1,4-fucosyltransferase. Similarly, LEC 11 cells expressing sialyl Le(x) bound E-selectin- but not P-selectin-expressing CHO cells. Sambucus nigra lectin, specific for the sialyl-2,6 beta Gal/GalNAc linkage, inhibited P-selectin but not E-selectin binding to HL60 cells. Although sialic acid and Le(x) are components of the P-selectin ligand and the E-selectin ligand, these results indicate that the ligands are related, having overlapping specificities, but are structurally distinct. A protein component containing sialyl Le(x) in proximity to sialyl-2,6 beta Gal structures on the P-selectin ligand may contribute to its specificity for P-selectin.
authors.affiliation: Genetics Institute Inc., Cambridge, Massachusetts 02140.
authors.forename: G R
authors.initials: GR
authors.lastname: Larsen
authors.forename: D
authors.initials: D
authors.lastname: Sako
authors.forename: T J
authors.initials: TJ
authors.lastname: Ahern
authors.forename: M
authors.initials: M
authors.lastname: Shaffer
authors.forename: J
authors.initials: J
authors.lastname: Erban
authors.forename: S A
authors.initials: SA
authors.lastname: Sajer
authors.forename: R M
authors.initials: RM
authors.lastname: Gibson
authors.forename: D D
authors.initials: DD
authors.lastname: Wagner
authors.forename: B C
authors.initials: BC
authors.lastname: Furie
authors.forename: B
authors.initials: B
authors.lastname: Furie
mesh_terms: D000818:Animals; D001483:Base Sequence; D016466:CHO Cells; D002240:Carbohydrate Sequence; D002448:Cell Adhesion; D015815:Cell Adhesion Molecules / Q000235:genetics / Q000378:metabolism*; D002460:Cell Line; D006224:Cricetinae; D004247:DNA / Q000235:genetics; D019040:E-Selectin; D006801:Humans; D007962:Leukocytes / Q000378:metabolism*; D016256:Lewis X Antigen / Q000378:metabolism; D008024:Ligands; D008969:Molecular Sequence Data; D019007:P-Selectin; D010980:Platelet Membrane Glycoproteins / Q000235:genetics / Q000378:metabolism*; D012794:Sialic Acids / Q000378:metabolism; D013379:Substrate Specificity; D014162:Transfection; D014415:Tunicamycin / Q000494:pharmacology
chemical_list: D015815:Cell Adhesion Molecules; D019040:E-Selectin; D016256:Lewis X Antigen; D008024:Ligands; D019007:P-Selectin; D010980:Platelet Membrane Glycoproteins; D012794:Sialic Acids; D014415:Tunicamycin; D004247:DNA