title: L- and P-selectins collaborate to support leukocyte rolling in vivo when high-affinity P-selectin-P-selectin glycoprotein ligand-1 interaction is inhibited.
abstract: P-selectin glycoprotein ligand-1 (PSGL-1) binding to P-selectin controls early leukocyte rolling during inflammation. Interestingly, antibodies and pharmacological inhibitors (eg, rPSGL-Ig) that target the N-terminus of PSGL-1 reduce but do not abolish P-selectin-dependent leukocyte rolling in vivo whereas PSGL-1-deficient mice have almost no P-selectin-dependent rolling. We have investigated mechanisms of P-selectin-dependent, PSGL-1-independent rolling using intravital microscopy. Initially we used fluorescent microspheres to study the potential of L-selectin and the minimal selectin ligand sialyl Lewis(x) (sLe(x)) to interact with postcapillary venules in the absence of PSGL-1. Microspheres coated with combinations of L-selectin and sLe(x) interacted with surgically stimulated cremaster venules in a P-selectin-dependent manner. Microspheres coated with either L-selectin or sLe(x) alone showed less evidence of interaction. We also investigated leukocyte rolling in the presence of PSGL-1 antibody or inhibitor (rPSGL-Ig), both of which partially inhibited P-selectin-dependent leukocyte rolling. Residual rolling was substantially inhibited by L-selectin-blocking antibody or a previously described sLe(x) mimetic (CGP69669A). Together these data suggest that leukocytes can continue to roll in the absence of optimal P-selectin/PSGL-1 interaction using an alternative mechanism that involves P-selectin-, L-selectin-, and sLe(x)-bearing ligands.
authors.affiliation: Cardiovascular Research Unit, University of Sheffield, Sheffield, UK.
authors.forename: Victoria C
authors.initials: VC
authors.lastname: Ridger
authors.forename: Paul G
authors.initials: PG
authors.lastname: Hellewell
authors.forename: Keith E
authors.initials: KE
authors.lastname: Norman
mesh_terms: D000818:Animals; D019921:Biotinylation; D002448:Cell Adhesion; D046508:Culture Techniques; D006023:Glycoproteins / Q000378:metabolism; D019041:L-Selectin / Q000378:metabolism*; D036904:Leukocyte Rolling; D007962:Leukocytes / Q000166:cytology* / Q000378:metabolism; D008024:Ligands; D008297:Male; D008562:Membrane Glycoproteins / Q000378:metabolism*; D051379:Mice; D008810:Mice, Inbred C57BL; D008853:Microscopy; D008863:Microspheres; D008954:Models, Biological; D009844:Oligosaccharides / Q000378:metabolism; D019007:P-Selectin / Q000378:metabolism*; D011485:Protein Binding; D000080506:Sialyl Lewis X Antigen; D013997:Time Factors
chemical_list: D006023:Glycoproteins; D008024:Ligands; D008562:Membrane Glycoproteins; D009844:Oligosaccharides; D019007:P-Selectin; C084882:P-selectin ligand protein; D000080506:Sialyl Lewis X Antigen; D019041:L-Selectin
references.citation: Cell. 1996 Aug 23;86(4):643-53
references.pmid: 8752218
references.citation: J Exp Med. 2003 May 19;197(10):1355-63
references.pmid: 12756271
references.citation: J Cell Biol. 1996 Nov;135(3):849-65
references.pmid: 8909556
references.citation: Biophys J. 1996 Nov;71(5):2902-7
references.pmid: 8913627
references.citation: J Cell Biol. 1997 Apr 21;137(2):509-19
references.pmid: 9128259
references.citation: Circ Res. 1991 Oct;69(4):1034-41
references.pmid: 1934331
references.citation: J Exp Med. 1994 Nov 1;180(5):1785-92
references.pmid: 7525838
references.citation: J Am Coll Cardiol. 2003 Jul 16;42(2):375-7
references.pmid: 12875779
references.citation: J Cell Biol. 2003 Nov 10;163(3):649-59
references.pmid: 14597772
references.citation: Biochemistry. 1991 Feb 12;30(6):1561-71
references.pmid: 1671554
references.citation: Cell. 1991 Sep 6;66(5):921-33
references.pmid: 1716182
references.citation: J Exp Med. 1995 Feb 1;181(2):669-75
references.pmid: 7530761
references.citation: Nature. 1995 Feb 16;373(6515):615-20
references.pmid: 7531823
references.citation: Immunity. 1994 Jul;1(4):247-60
references.pmid: 7534203
references.citation: Cell. 1995 Oct 20;83(2):323-31
references.pmid: 7585949
references.citation: Blood. 1995 Dec 15;86(12):4417-21
references.pmid: 8541529
references.citation: Biophys J. 1997 Jun;72(6):2820-33
references.pmid: 9168056
references.citation: Blood. 1997 Sep 1;90(5):1934-42
references.pmid: 9292527
references.citation: Blood. 1998 Jan 15;91(2):475-83
references.pmid: 9427700
references.citation: J Biol Chem. 1999 Aug 27;274(35):24838-48
references.pmid: 10455156
references.citation: Int Immunol. 1995 Oct;7(10):1557-65
references.pmid: 8562500
references.citation: J Exp Med. 1999 Dec 20;190(12):1769-82
references.pmid: 10601352
references.citation: J Exp Med. 2000 Jan 3;191(1):189-94
references.pmid: 10620617
references.citation: J Leukoc Biol. 2000 Feb;67(2):196-205
references.pmid: 10670580
references.citation: J Exp Med. 2000 Apr 17;191(8):1413-22
references.pmid: 10770806
references.citation: Biophys J. 2000 Aug;79(2):694-706
references.pmid: 10920004
references.citation: Blood. 2000 Nov 15;96(10):3585-91
references.pmid: 11071658
references.citation: Cell. 2000 Oct 27;103(3):467-79
references.pmid: 11081633
references.citation: J Biol Chem. 2000 Dec 15;275(50):39569-78
references.pmid: 10978329
references.citation: Circulation. 2001 Feb 20;103(7):1000-5
references.pmid: 11181476
references.citation: Microcirculation. 2001 Feb;8(1):15-24
references.pmid: 11296849
references.citation: Blood. 2001 Jun 15;97(12):3812-9
references.pmid: 11389021
references.citation: J Immunol. 2001 Aug 15;167(4):2268-74
references.pmid: 11490014
references.citation: Microcirculation. 2001 Aug;8(4):243-9
references.pmid: 11528532
references.citation: Blood. 2002 Jul 15;100(2):531-8
references.pmid: 12091345
references.citation: FASEB J. 2002 Sep;16(11):1461-2
references.pmid: 12205048
references.citation: Blood. 2003 Apr 1;101(7):2661-6
references.pmid: 12480714
references.citation: Blood. 2003 Apr 15;101(8):3249-56
references.pmid: 12480716
references.citation: Circulation. 2003 May 6;107(17):2244-9
references.pmid: 12707243
references.citation: Nature. 2003 May 8;423(6936):190-3
references.pmid: 12736689
references.citation: J Clin Invest. 1996 Sep 1;98(5):1081-7
references.pmid: 8787668