title: Peritoneal macrophages express both P-selectin and PSGL-1.
abstract: Macrophages, phagocytic cells involved in an early phase of host defense, are known to express the P-selectin ligand, PSGL-1. Heretofore, P-selectin has only been found on platelets and endothelial cells. Here, we demonstrate that peritoneal macrophages isolated by peritoneal lavage of unchallenged mice express P-selectin on the plasma membrane. The peritoneal macrophages synthesize P-selectin, as indicated by metabolic labeling experiments. P-Selectin is constitutively expressed on the extracellular surface of macrophages but is only partially colocalized with PSGL-1. P-Selectin is rapidly translocated from the macrophage plasma membrane to intracellular vesicles and to lysosomes. Peritoneal macrophages assemble into cell strings under flow conditions based upon macrophage-macrophage interactions mediated by P-selectin and PSGL-1. This is the first description of a leukocyte shown to express both P-selectin and PSGL-1.
authors.affiliation: Center for Hemostasis, Thrombosis and Vascular Biology, Beth Israel Deaconess Medical Center, Harvard Medical School, 330 Brookline Ave., Boston, MA 02215, USA.
authors.forename: Boris
authors.initials: B
authors.lastname: Tchernychev
authors.forename: Bruce
authors.initials: B
authors.lastname: Furie
authors.forename: Barbara C
authors.initials: BC
authors.lastname: Furie
mesh_terms: D000818:Animals; D002448:Cell Adhesion / Q000502:physiology; D002462:Cell Membrane / Q000378:metabolism; D002478:Cells, Cultured; D019041:L-Selectin / Q000235:genetics / Q000378:metabolism; D008024:Ligands; D008262:Macrophage Activation; D017737:Macrophages, Peritoneal / Q000378:metabolism* / Q000648:ultrastructure; D008562:Membrane Glycoproteins / Q000235:genetics / Q000378:metabolism*; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism; D051379:Mice; D018345:Mice, Knockout; D019007:P-Selectin / Q000235:genetics / Q000378:metabolism*; D019010:Vascular Cell Adhesion Molecule-1 / Q000378:metabolism
chemical_list: D008024:Ligands; D008562:Membrane Glycoproteins; D008565:Membrane Proteins; D019007:P-Selectin; C084882:P-selectin ligand protein; D019010:Vascular Cell Adhesion Molecule-1; D019041:L-Selectin