title: P-selectin glycoprotein ligand-1 is essential for adhesion to P-selectin but not E-selectin in stably transfected hematopoietic cell lines.
abstract: P-selectin (CD62P) is a member of the selectin family of adhesion molecules involved in the regulation of leukocyte traffic. P-selectin glycoprotein ligand-1 (PSGL-1) is a mucin-like molecule that is thought to be a primary ligand for P-selectin. The interaction of P-selectin with PSGL-1 results in leukocyte rolling and recruitment of leukocytes to sites of inflammation and tissue injury. However, expression of PSGL-1 protein alone is insufficient for binding to P-selectin. Several posttranslational modifications of PSGL-1, including sialylation, sulfation, and fucosylation by alpha 1,3-fucosyltransferase(s) (FucT), are required for functional interaction with P-selectin. Recently, several groups have reported that PSGL-1 might also serve as a ligand for E-selectin. Differential posttranslational modifications of PSGL-1 may determine whether it can interact with either P- or E-selectin or both. To determine whether PSGL-1 is essential for adhesion to P- or E-selectin, we have constructed and analyzed a panel of stably transfected K562 cells. K562 cells express FucT-IV but not FucT-VII or PSGL-1, and do not bind to either E- or P-selectin. K562 cells transfected with PSGL-1 cDNA also did not bind to either P- or E-selectin. Binding to P-selectin occurred only when K562 cells were cotransfected with both FucT-VII and PSGL-1. In contrast, expression of FucT-VII alone was sufficient for E-selectin binding. These data demonstrate that expression of PSGL-1 is not required for adhesion of a stably transfected hematopoietic cell line to E-selectin, and suggest that FucT-IV alone cannot properly modify PSGL-1, expressed in transfected K562 cells, to bind P-selectin.
authors.affiliation: Department of Microbiology-Immunology, Northwestern Medical School, Chicago, IL 60611, USA.
authors.forename: K R
authors.initials: KR
authors.lastname: Snapp
authors.forename: A J
authors.initials: AJ
authors.lastname: Wagers
authors.forename: R
authors.initials: R
authors.lastname: Craig
authors.forename: L M
authors.initials: LM
authors.lastname: Stoolman
authors.forename: G S
authors.initials: GS
authors.lastname: Kansas
mesh_terms: D002241:Carbohydrates / Q000096:biosynthesis / Q000097:blood; D002448:Cell Adhesion; D019040:E-Selectin / Q000097:blood*; D005647:Fucosyltransferases / Q000096:biosynthesis / Q000097:blood; D006412:Hematopoietic Stem Cells / Q000201:enzymology / Q000378:metabolism / Q000502:physiology*; D018056:Hemorheology; D006801:Humans; D004915:Leukemia, Erythroblastic, Acute / Q000097:blood* / Q000235:genetics / Q000378:metabolism; D008024:Ligands; D008562:Membrane Glycoproteins / Q000096:biosynthesis / Q000097:blood* / Q000502:physiology; D019007:P-Selectin / Q000097:blood* / Q000502:physiology; D014162:Transfection; D014407:Tumor Cells, Cultured
chemical_list: D002241:Carbohydrates; D019040:E-Selectin; D008024:Ligands; D008562:Membrane Glycoproteins; D019007:P-Selectin; C084882:P-selectin ligand protein; D005647:Fucosyltransferases; C031692:galactoside 3-fucosyltransferase