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Rodger P Mcever - One of the best experts on this subject based on the ideXlab platform.
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p selectin Glycoprotein ligand 1 forms dimeric interactions with e selectin but monomeric interactions with l selectin on cell surfaces
PLOS ONE, 2013Co-Authors: Yan Zhang, Rodger P Mcever, Ning Jiang, Veronika I Zarnitsyna, Arkadiusz G Klopocki, Cheng ZhuAbstract:Interactions of selectins with cell surface glycoconjugates mediate the first step of the adhesion and signaling cascade that recruits circulating leukocytes to sites of infection or injury. P-Selectin dimerizes on the surface of endothelial cells and forms dimeric bonds with P-Selectin Glycoprotein Ligand-1 (PSGL-1), a homodimeric sialomucin on leukocytes. It is not known whether leukocyte L-selectin or endothelial cell E-selectin are monomeric or oligomeric. Here we used the micropipette technique to analyze two-dimensional binding of monomeric or dimeric L- and E-selectin with monomeric or dimeric PSGL-1. Adhesion frequency analysis demonstrated that E-selectin on human aortic endothelial cells supported dimeric interactions with dimeric PSGL-1 and monomeric interactions with monomeric PSGL-1. In contrast, L-selectin on human neutrophils supported monomeric interactions with dimeric or monomeric PSGL-1. Our work provides a new method to analyze oligomeric cross-junctional molecular binding at the interface of two interacting cells.
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Characterization of a sialic acid- and P-Selectin Glycoprotein Ligand-1-independent adhesin activity in the granulocytotropic bacterium Anaplasma phagocytophilum.
Cellular microbiology, 2006Co-Authors: Dexter V. Reneer, Rodger P Mcever, Richard D Cummings, Tadayuki Yago, Sarah A. Kearns, Jonathan T. Sims, Jason A. CarlyonAbstract:Anaplasma phagocytophilum, the aetiologic agent of human granulocytic anaplasmosis, is an obligate intracellular bacterium that colonizes neutrophils and neutrophil precursors. The granulocytotropic bacterium uses multiple adhesins that cooperatively bind to the N-terminal region of P-Selectin Glycoprotein Ligand-1 (PSGL-1) and to sialyl Lewis x (sLe(x)) expressed on myeloid cell surfaces. Recognition of sLe(x) occurs through interactions with alpha2,3-sialic acid and alpha1,3-fucose. It is unknown whether other bacteria-host cell interactions are involved. In this study, we have enriched for A. phagocytophilum organisms that do not rely on sialic acid for cellular adhesion and entry by maintaining strain NCH-1 in HL-60 cells that are severely undersialylated. The selected bacteria, termed NCH-1A, also exhibit lessened dependencies on PSGL-1 and alpha1,3-fucose. Optimal adhesion and invasion by NCH-1A require interactions with the known determinants (sialic acid, PSGL-1 and alpha1,3-fucose), but none of them is absolutely necessary. NCH-1A binding to sLe(x)-modified PSGL-1 requires recognition of the known determinants in the same manners as other A. phagocytophilum strains. These data suggest that A. phagocytophilum expresses a separate adhesin from those targeting sialic acid, alpha1,3-fucose and the N-terminal region of PSGL-1. We propose that NCH-1A upregulates expression of this adhesin.
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low force decelerates l selectin dissociation from p selectin Glycoprotein ligand 1 and endoglycan
Journal of Biological Chemistry, 2004Co-Authors: Krishna K Sarangapani, Rodger P Mcever, Arkadiusz G Klopocki, Tadayuki Yago, Michael B Lawrence, Claudia B Fieger, Steven D Rosen, Cheng ZhuAbstract:Selectin-ligand interactions mediate the tethering and rolling of circulating leukocytes on vascular surfaces during inflammation and immune surveillance. To support rolling, these interactions are thought to have rapid off-rates that increase slowly as wall shear stress increases. However, the increase of off-rate with force, an intuitive characteristic named slip bonds, is at odds with a shear threshold requirement for selectin-mediated cell rolling. As shear drops below the threshold, fewer cells roll and those that do roll less stably and with higher velocity. We recently demonstrated a low force regime where the off-rate of P-Selectin interacting with P-Selectin Glycoprotein Ligand-1 (PSGL-1) decreased with increasing force. This counter-intuitive characteristic, named catch bonds, might partially explain the shear threshold phenomenon. Because L-selectin-mediated cell rolling exhibits a much more pronounced shear threshold, we used atomic force microscopy and flow chamber experiments to determine off-rates of L-selectin interacting with their physiological ligands and with an antibody. Catch bonds were observed at low forces for L-selectin-PSGL-1 interactions coinciding with the shear threshold range, whereas slip bonds were observed at higher forces. These catch-slip transitional bonds were also observed for L-selectin interacting with endoglycan, a newly identified PSGL-1-like ligand. By contrast, only slip bonds were observed for L-selectin-antibody interactions. These findings suggest that catch bonds contribute to the shear threshold for rolling and are a common characteristic of selectin-ligand interactions.
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P-Selectin Glycoprotein Ligand-1 Mediates L-Selectin–dependent Leukocyte Rolling in Venules
The Journal of experimental medicine, 2003Co-Authors: Markus Sperandio, Rodger P Mcever, Lijun Xia, Timothy S. Olson, Michael L. Smith, S. Bradley Forlow, Klaus LeyAbstract:Leukocyte rolling in postcapillary venules of inflamed tissues is reduced in L-selectin–deficient mice and mice treated with L-selectin blocking antibodies, but the Glycoprotein ligand for L-selectin in inflamed venules is unknown. Here, we show that L-selectin–dependent rolling after P-Selectin blockade is completely absent in P-Selectin Glycoprotein Ligand-1 (PSGL-1)−/− mice or wild-type mice treated with a PSGL-1 blocking monoclonal antibody. Immunohistochemistry and flow cytometry failed to show PSGL-1 expression on resting or inflamed endothelium or on platelets. To investigate whether leukocyte-expressed PSGL-1 is mediating L-selectin–dependent rolling, we reconstituted lethally irradiated wild-type mice with PSGL-1−/− bone marrow cells. These chimeric mice showed no L-selectin–dependent rolling, suggesting that leukocyte-expressed PSGL-1 mediates L-selectin–dependent rolling. Frame-to-frame video analysis of L-selectin–dependent rolling in wild-type mice showed that the majority of observed L-selectin–dependent leukocyte rolling was between free flowing leukocytes and already adherent leukocytes or possibly leukocyte fragments, followed by E-selectin–dependent leukocyte rolling along the endothelium. Leukocyte rolling was significantly slower for leukocyte–endothelial than leukocyte–leukocyte interactions. We conclude that leukocyte-expressed PSGL-1 serves as the main L-selectin ligand in inflamed postcapillary venules. L-selectin binding to PSGL-1 initiates tethering events that enable L-selectin–independent leukocyte-endothelial interactions. These findings provide a molecular mechanism for the inflammatory defects seen in L-selectin–deficient mice.
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N-terminal residues in murine P-Selectin Glycoprotein Ligand-1 required for binding to murine P-Selectin
Blood, 2002Co-Authors: Lijun Xia, Richard D Cummings, J. Michael Mcdaniel, Vishwanath Ramachandran, Kiem N. Nguyen, Rodger P MceverAbstract:P-Selectin binds to the N-terminal region of human P-Selectin Glycoprotein Ligand-1 (PSGL-1). For optimal binding, this region requires sulfation on 3 tyrosines and specific core-2 O-glycosylation on a threonine. P-Selectin is also thought to bind to the N terminus of murine PSGL-1, although it has a very different amino acid sequence than human PSGL-1. Murine PSGL-1 has potential sites for sulfation at Tyr13 and Tyr15 and for O-glycosylation at Thr14 and Thr17. We expressed murine PSGL-1 or constructs with substitutions of these residues in transfected Chinese hamster ovary cells that coexpressed the glycosyltransferases required for binding to P-Selectin. The cells were assayed for binding to fluid-phase P-Selectin and for tethering and rolling on P-Selectin under flow. In both assays, substitution of Tyr13 or Thr17 markedly diminished, but did not eliminate, binding to P-Selectin. In contrast, substitution of Tyr15 or Thr14 did not affect binding. Substitution of all 4 residues eliminated binding. Treatment of cells with chlorate, an inhibitor of sulfation, markedly reduced binding of wild-type PSGL-1 to P-Selectin but did not further decrease binding of PSGL-1 with substitutions of both tyrosines. These data suggest that sulfation of Tyr13 and O-glycosylation of Thr17 are necessary for murine PSGL-1 to bind optimally to P-Selectin. Because it uses only one tyrosine, murine PSGL-1 may rely more on other peptide components and O-glycosylation to bind to P-Selectin than does human PSGL-1.
Klaus Ley - One of the best experts on this subject based on the ideXlab platform.
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P-Selectin Glycoprotein Ligand-1 in T cells.
Current opinion in hematology, 2017Co-Authors: Michael Abadier, Klaus LeyAbstract:Purpose of reviewWe review P-Selectin Glycoprotein Ligand-1 (PSGL-1) as a selectin and chemokine-binding adhesion molecule. PSGL-1 is widely studied in neutrophils. Here, we focus on T cells, because PSGL-1 was recently described as a major immunomodulatory molecule during viral infection. PSGL-1 al
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Critical role of endothelial P-Selectin Glycoprotein ligand 1 in chronic murine ileitis
The Journal of experimental medicine, 2006Co-Authors: Jesus Rivera-nieves, Tracy L. Burcin, Timothy S. Olson, Margaret A. Morris, Marcia Mcduffie, Fabio Cominelli, Klaus LeyAbstract:L-selectin ligands might be relevant for inflammatory cell trafficking into the small intestine in a spontaneous model of chronic ileitis (i.e., SAMP1/YitFc mice). Immunoblockade of peripheral node addressin or mucosal addressin cell adhesion molecule 1 failed to ameliorate ileitis, whereas P-Selectin Glycoprotein ligand 1 (PSGL-1) neutralization attenuated both the adoptively transferred and spontaneous disease. PSGL-1 was detected in venules of mesenteric lymph node and small intestine by immunohistochemistry and confirmed by real-time reverse transcription polymerase chain reaction and flow cytometry. In addition, reconstitution of wild-type mice with PSGL-1−/− bone marrow demonstrated that PSGL-1 messenger RNA and PSGL-1 protein expression remained on endothelium, localized within mesenteric lymph node and small intestine. Endothelial PSGL-1 bound P-Selectin–IgG and its blockade or genetic deletion altered the recruitment of lymphocytes to the small intestine, as revealed by intravital microscopy and homing studies. Endothelial expression of PSGL-1 adds a new dimension to the various cellular interactions involved in small intestinal recruitment. Thus, the multiple roles of PSGL-1 may explain why targeting this single adhesion molecule results in attenuation of chronic murine ileitis, a disease previously resistant to antiadhesion molecule strategies.
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P-Selectin Glycoprotein Ligand-1 Mediates L-Selectin–dependent Leukocyte Rolling in Venules
The Journal of experimental medicine, 2003Co-Authors: Markus Sperandio, Rodger P Mcever, Lijun Xia, Timothy S. Olson, Michael L. Smith, S. Bradley Forlow, Klaus LeyAbstract:Leukocyte rolling in postcapillary venules of inflamed tissues is reduced in L-selectin–deficient mice and mice treated with L-selectin blocking antibodies, but the Glycoprotein ligand for L-selectin in inflamed venules is unknown. Here, we show that L-selectin–dependent rolling after P-Selectin blockade is completely absent in P-Selectin Glycoprotein Ligand-1 (PSGL-1)−/− mice or wild-type mice treated with a PSGL-1 blocking monoclonal antibody. Immunohistochemistry and flow cytometry failed to show PSGL-1 expression on resting or inflamed endothelium or on platelets. To investigate whether leukocyte-expressed PSGL-1 is mediating L-selectin–dependent rolling, we reconstituted lethally irradiated wild-type mice with PSGL-1−/− bone marrow cells. These chimeric mice showed no L-selectin–dependent rolling, suggesting that leukocyte-expressed PSGL-1 mediates L-selectin–dependent rolling. Frame-to-frame video analysis of L-selectin–dependent rolling in wild-type mice showed that the majority of observed L-selectin–dependent leukocyte rolling was between free flowing leukocytes and already adherent leukocytes or possibly leukocyte fragments, followed by E-selectin–dependent leukocyte rolling along the endothelium. Leukocyte rolling was significantly slower for leukocyte–endothelial than leukocyte–leukocyte interactions. We conclude that leukocyte-expressed PSGL-1 serves as the main L-selectin ligand in inflamed postcapillary venules. L-selectin binding to PSGL-1 initiates tethering events that enable L-selectin–independent leukocyte-endothelial interactions. These findings provide a molecular mechanism for the inflammatory defects seen in L-selectin–deficient mice.
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single injection of p selectin or p selectin Glycoprotein ligand 1 monoclonal antibody blocks neointima formation after arterial injury in apolipoprotein e deficient mice
Circulation, 2003Co-Authors: William J Phillips, Kurt G Barringhaus, John M Sanders, Sean Hesselbacher, Ann C Czarnik, David Manka, Dietmar Vestweber, Klaus Ley, Ian J SarembockAbstract:Background— Emerging data suggest that P-Selectin, by controlling adhesion of white blood cells, may be important in limiting the response to vascular injury. Methods and Results— We tested the hypothesis that transient inhibition of P-Selectin with either anti-P-Selectin monoclonal antibody (mAb) or anti-P-Selectin Glycoprotein Ligand-1 (PSGL-1) mAb would reduce neointima formation in the setting of carotid denudation injury in atherosclerosis-prone apolipoprotein E−/− mice. Neointima formation at 28 days was reduced significantly, by 50% or 80%, by a single injection on the day of injury of 100 or 200 μg P-Selectin mAb RB 40.34 and by 55% by a single injection of 100 μg PSGL-1 mAb 4RA10 (P≤0.005). In addition, there was a significant reduction in neointimal macrophage content. Conclusions— These findings demonstrate that transient P-Selectin or PSGL-1 blockade at the time of arterial injury significantly limits plaque macrophage content and neointima formation in a dose-dependent manner after carotid de...
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p selectin Glycoprotein ligand 1 deficient mice have impaired leukocyte tethering to e selectin under flow
Journal of Clinical Investigation, 2002Co-Authors: Lijun Xia, Klaus Ley, Richard D Cummings, Markus Sperandio, Tadayuki Yago, Michael J Mcdaniel, Sonia Pearsonwhite, Rodger P MceverAbstract:P-Selectin Glycoprotein Ligand-1 (PSGL-1) mediates rolling of leukocytes on P-Selectin under flow. The Glycoproteins that enable leukocyte tethering to or rolling on E-selectin are not known. We used gene targeting to prepare PSGL-1–deficient (PSGL-1–/–) mice, which were healthy but had moderately elevated total blood leukocytes. Fluid-phase E-selectin bound to approximately 70% fewer sites on PSGL-1–/– than PSGL-1+/+ neutrophils. Compared with PSGL-1+/+ leukocytes, significantly fewer PSGL-1–/– leukocytes rolled on E-selectin in vitro, because their initial tethering to E-selectin was impaired. The residual cells that tethered rolled with the same shear resistance and velocities as PSGL-1+/+ leukocytes. Compared with PSGL-1+/+ mice, significantly fewer PSGL-1–/– leukocytes rolled on E-selectin in TNF-α–treated venules of cremaster muscle in which P-Selectin function was blocked by an mAb. The residual PSGL-1–/– leukocytes that tethered rolled with slow velocities equivalent to those of PSGL-1+/+ leukocytes. These results reveal a novel function for PSGL-1 in tethering leukocytes to E-selectin under flow.
Richard D Cummings - One of the best experts on this subject based on the ideXlab platform.
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Characterization of a sialic acid- and P-Selectin Glycoprotein Ligand-1-independent adhesin activity in the granulocytotropic bacterium Anaplasma phagocytophilum.
Cellular microbiology, 2006Co-Authors: Dexter V. Reneer, Rodger P Mcever, Richard D Cummings, Tadayuki Yago, Sarah A. Kearns, Jonathan T. Sims, Jason A. CarlyonAbstract:Anaplasma phagocytophilum, the aetiologic agent of human granulocytic anaplasmosis, is an obligate intracellular bacterium that colonizes neutrophils and neutrophil precursors. The granulocytotropic bacterium uses multiple adhesins that cooperatively bind to the N-terminal region of P-Selectin Glycoprotein Ligand-1 (PSGL-1) and to sialyl Lewis x (sLe(x)) expressed on myeloid cell surfaces. Recognition of sLe(x) occurs through interactions with alpha2,3-sialic acid and alpha1,3-fucose. It is unknown whether other bacteria-host cell interactions are involved. In this study, we have enriched for A. phagocytophilum organisms that do not rely on sialic acid for cellular adhesion and entry by maintaining strain NCH-1 in HL-60 cells that are severely undersialylated. The selected bacteria, termed NCH-1A, also exhibit lessened dependencies on PSGL-1 and alpha1,3-fucose. Optimal adhesion and invasion by NCH-1A require interactions with the known determinants (sialic acid, PSGL-1 and alpha1,3-fucose), but none of them is absolutely necessary. NCH-1A binding to sLe(x)-modified PSGL-1 requires recognition of the known determinants in the same manners as other A. phagocytophilum strains. These data suggest that A. phagocytophilum expresses a separate adhesin from those targeting sialic acid, alpha1,3-fucose and the N-terminal region of PSGL-1. We propose that NCH-1A upregulates expression of this adhesin.
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N-terminal residues in murine P-Selectin Glycoprotein Ligand-1 required for binding to murine P-Selectin
Blood, 2002Co-Authors: Lijun Xia, Richard D Cummings, J. Michael Mcdaniel, Vishwanath Ramachandran, Kiem N. Nguyen, Rodger P MceverAbstract:P-Selectin binds to the N-terminal region of human P-Selectin Glycoprotein Ligand-1 (PSGL-1). For optimal binding, this region requires sulfation on 3 tyrosines and specific core-2 O-glycosylation on a threonine. P-Selectin is also thought to bind to the N terminus of murine PSGL-1, although it has a very different amino acid sequence than human PSGL-1. Murine PSGL-1 has potential sites for sulfation at Tyr13 and Tyr15 and for O-glycosylation at Thr14 and Thr17. We expressed murine PSGL-1 or constructs with substitutions of these residues in transfected Chinese hamster ovary cells that coexpressed the glycosyltransferases required for binding to P-Selectin. The cells were assayed for binding to fluid-phase P-Selectin and for tethering and rolling on P-Selectin under flow. In both assays, substitution of Tyr13 or Thr17 markedly diminished, but did not eliminate, binding to P-Selectin. In contrast, substitution of Tyr15 or Thr14 did not affect binding. Substitution of all 4 residues eliminated binding. Treatment of cells with chlorate, an inhibitor of sulfation, markedly reduced binding of wild-type PSGL-1 to P-Selectin but did not further decrease binding of PSGL-1 with substitutions of both tyrosines. These data suggest that sulfation of Tyr13 and O-glycosylation of Thr17 are necessary for murine PSGL-1 to bind optimally to P-Selectin. Because it uses only one tyrosine, murine PSGL-1 may rely more on other peptide components and O-glycosylation to bind to P-Selectin than does human PSGL-1.
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Glycosulfopeptides modeled on P-Selectin Glycoprotein ligand 1 inhibit P-Selectin-dependent leukocyte rolling in vivo
The FASEB Journal, 2002Co-Authors: Anne E. R. Hicks, Rodger P Mcever, Richard D Cummings, Anne Leppänen, Paul G. Hellewell, Keith E. NormanAbstract:SPECIFIC AIMSThe aim was to investigate whether rationally designed selectin antagonists (glycosulfopeptides) inhibit P-Selectin-dependent leukocyte rolling in living blood vessels.PRINCIPAL FINDINGS1. Glycosulfopeptides (2-GSP-6, 4-GSP-6) modeled on 18 amino acids from the NH2 terminus of mature human P-Selectin Glycoprotein ligand 1 (PSGL-1) enzymatically modified in vitro to express sialyl Lewisx (sLex) and sulfated tyrosine at appropriate locations inhibited preexisting P-Selectin-dependent leukocyte rolling in vivo (Fig. 1⤻ ). Control glycosulfopeptides (2-GSP-1, 4-GSP-1) carrying only N-acetylgalactosamine in place of sLex did not inhibit P-Selectin-dependent leukocyte rolling. Figure 1.a) Effects of different GSP on proportion of leukocytes rolling through observed venules. Baseline leukocyte rolling was determined from a 1 min observation recorded 30 min after surgical preparation of the cremaster for intravital microscopy. Glycosulfopeptides were injected at 31 min and effects determined between ...
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p selectin Glycoprotein ligand 1 deficient mice have impaired leukocyte tethering to e selectin under flow
Journal of Clinical Investigation, 2002Co-Authors: Lijun Xia, Klaus Ley, Richard D Cummings, Markus Sperandio, Tadayuki Yago, Michael J Mcdaniel, Sonia Pearsonwhite, Rodger P MceverAbstract:P-Selectin Glycoprotein Ligand-1 (PSGL-1) mediates rolling of leukocytes on P-Selectin under flow. The Glycoproteins that enable leukocyte tethering to or rolling on E-selectin are not known. We used gene targeting to prepare PSGL-1–deficient (PSGL-1–/–) mice, which were healthy but had moderately elevated total blood leukocytes. Fluid-phase E-selectin bound to approximately 70% fewer sites on PSGL-1–/– than PSGL-1+/+ neutrophils. Compared with PSGL-1+/+ leukocytes, significantly fewer PSGL-1–/– leukocytes rolled on E-selectin in vitro, because their initial tethering to E-selectin was impaired. The residual cells that tethered rolled with the same shear resistance and velocities as PSGL-1+/+ leukocytes. Compared with PSGL-1+/+ mice, significantly fewer PSGL-1–/– leukocytes rolled on E-selectin in TNF-α–treated venules of cremaster muscle in which P-Selectin function was blocked by an mAb. The residual PSGL-1–/– leukocytes that tethered rolled with slow velocities equivalent to those of PSGL-1+/+ leukocytes. These results reveal a novel function for PSGL-1 in tethering leukocytes to E-selectin under flow.
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Affinity and Kinetic Analysis of P-Selectin Binding to P-Selectin Glycoprotein Ligand-1
The Journal of biological chemistry, 1998Co-Authors: Padmaja Mehta, Richard D Cummings, Rodger P MceverAbstract:Leukocytes use the cell-surface mucin P-Selectin Glycoprotein Ligand-1 (PSGL-1) to tether to and roll on P-Selectin on activated endothelial cells and platelets. By using surface plasmon resonance, we measured the affinity and kinetics of binding of soluble monomeric human P-Selectin to immobilized PSGL-1 from human neutrophils. Binding was specific, as documented by its Ca2+-dependence, its inhibition by specific monoclonal antibodies to P-Selectin and PSGL-1, and its abrogation by treating PSGL-1 with sialidase. Similar binding was observed for soluble P-Selectin that contained the lectin and epidermal growth factor domains plus all nine consensus repeats, and for a soluble construct that contained only the lectin and epidermal growth factor domains. Soluble P-Selectin bound saturably to a single class of sites on PSGL-1 with a dissociation constant (Kd) of 320 +/- 20 nM. The measured koff was 1.4 +/- 0.1 s-1, and the calculated kon was 4.4 x 10(6) M-1 s-1. We conclude that monomeric P-Selectin binds to PSGL-1 with fast association and dissociation rates and relatively high affinity. These features may be important for efficient tethering and rolling of leukocytes at physiologic densities of PSGL-1 and P-Selectin.
Olivier Spertini - One of the best experts on this subject based on the ideXlab platform.
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P-Selectin Glycoprotein Ligand-1 Decameric Repeats Regulate Selectin-dependent Rolling under Flow Conditions
The Journal of biological chemistry, 2008Co-Authors: Caroline Tauxe, Marc Schapira, Xun Xie, Magali Joffraud, Manuel Martinez, Olivier SpertiniAbstract:Abstract P-Selectin Glycoprotein Ligand-1 (PSGL-1) interacts with selectins to support leukocyte rolling along vascular wall. L- and P-Selectin bind to N-terminal tyrosine sulfate residues and to core-2 O-glycans attached to Thr-57, whereas tyrosine sulfation is not required for E-selectin binding. PSGL-1 extracellular domain contains decameric repeats, which extend L- and P-Selectin binding sites far above the plasma membrane. We hypothesized that decamers may play a role in regulating PSGL-1 interactions with selectins. Chinese hamster ovary cells expressing wild-type PSGL-1 or PSGL-1 molecules exhibiting deletion or substitution of decamers with the tandem repeats of platelet Glycoprotein Ibα were compared in their ability to roll on selectins and to bind soluble L- or P-Selectin. Deletion of decamers abrogated soluble L-selectin binding and cell rolling on L-selectin, whereas their substitution partially reversed these diminutions. P-Selectin-dependent interactions with PSGL-1 were less affected by decamer deletion. Videomicroscopy analysis showed that decamers are required to stabilize L-selectin-dependent rolling. Importantly, adhesion assays performed on recombinant decamers demonstrated that they directly bind to E-selectin and promote slow rolling. Our results indicate that the role of decamers is to extend PSGL-1 N terminus far above the cell surface to support and stabilize leukocyte rolling on L- or P-Selectin. In addition, they function as a cell adhesion receptor, which supports ∼80% of E-selectin-dependent rolling.
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Evolutionary conservation of P-Selectin Glycoprotein Ligand-1 primary structure and function.
BMC evolutionary biology, 2007Co-Authors: Bénédicte Baïsse, Frédérique Galisson, Sylvain Giraud, Marc Schapira, Olivier SpertiniAbstract:Background P-Selectin Glycoprotein Ligand-1 (PSGL-1) plays a critical role in recruiting leukocytes in inflammatory lesions by mediating leukocyte rolling on selectins. Core-2 O-glycosylation of a N-terminal threonine and sulfation of at least one tyrosine residue of PSGL-1 are required for L- and P-Selectin binding. Little information is available on the intra- and inter-species evolution of PSGL-1 primary structure. In addition, the evolutionary conservation of selectin binding site on PSGL-1 has not been previously examined in detail. Therefore, we performed multiple sequence alignment of PSGL-1 amino acid sequences of 14 mammals (human, chimpanzee, rhesus monkey, bovine, pig, rat, tree-shrew, bushbaby, mouse, bat, horse, cat, sheep and dog) and examined mammalian PSGL-1 interactions with human selectins.
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Modification of P-Selectin Glycoprotein Ligand-1 with a natural killer cell-restricted sulfated lactosamine creates an alternate ligand for L-selectin
Proceedings of the National Academy of Sciences of the United States of America, 2000Co-Authors: Pascale Andre, Olivier Spertini, Françoise Dignat-george, Sophie Guia, Pascal Rihet, Hervé Brailly, José Sampol, Paul Anderson, Eric VivierAbstract:Natural killer (NK) cells are components of the innate immune system that can recognize and kill virally infected cells, tumor cells, and allogeneic cells without prior sensitization. NK cells also elaborate cytokines (e.g., interferon-γ and tumor necrosis factor-α) and chemokines (e.g., macrophage inflammatory protein-1α) that promote the acquisition of antigen-specific immunity. NK cell differentiation is accompanied by the cell surface expression of a mucin-like Glycoprotein bearing an NK cell-restricted keratan sulfate-related lactosamine carbohydrate, the PEN5 epitope. Here, we report that PEN5 is a post-translational modification of P-Selectin Glycoprotein Ligand-1 (PSGL-1). The PEN5 epitope creates on PSGL-1 a unique binding site for L-selectin, which is independent of PSGL-1 tyrosine sulfation. On the surface of NK cells, the expression of PEN5 is coordinated with the disappearance of L-selectin and the up-regulation of Killer cell Ig-like Receptors (KIR). These results indicate that NK cell differentiation is accompanied by the acquisition of a unique carbohydrate, PEN5, that can serve as part of a combination code to deliver KIR+ NK cells to specific tissues.
Reyhan Diz-kucukkaya - One of the best experts on this subject based on the ideXlab platform.
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P-Selectin Glycoprotein Ligand-1 VNTR polymorphisms and risk of thrombosis in the antiphospholipid syndrome
Annals of the rheumatic diseases, 2007Co-Authors: Reyhan Diz-kucukkaya, Murat Inanc, Vahid Afshar-kharghan, Q Ed Zhang, José A. López, Yuksel PekcelenAbstract:Objectives: Antiphospholipid antibodies (aPLA) have been shown to enhance thrombus formation by increasing the expression of adhesive receptors such as P-Selectin on endothelial cells. The P-Selectin counter-receptor on leucocytes is P-Selectin Glycoprotein Ligand-1 (PSGL-1). We have previously described a variable number of tandem repeats (VNTR) polymorphism in the mucin-like region of PSGL-1, with three alleles: allele A, 16 repeats; allele B, 15 repeats; and allele C, 14 repeats. Methods: We compared the PSGL-1 VNTR allele and genotype frequencies in 90 patients with antiphospholipid syndrome (APS) with thrombosis, 39 patients with persistent aPLA positivity without thrombosis, and 203 healthy controls. Results: The frequency of the B allele was significantly higher in patients with APS with thrombosis compared with patients without thrombosis (p = 0.023). When we compared the groups by genotype frequencies, we found a markedly higher frequency of the AB genotype in patients with APS with thrombosis than in aPLA-positive patients without thrombosis (38.9% vs 10.3%, p = 0.001) or in normal population (38.9% vs 22.2%, p Conclusions: We suggest that the VNTR polymorphism of PSGL-1 is a significant determinant of thrombotic predisposition in patients with APS. Furthermore, risk appears to correlate best with the combination of alleles inherited rather than with the presence of any particular allele.
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The association of P-Selectin Glycoprotein Ligand-1 VNTR polymorphisms with coronary stent restenosis
Journal of thrombosis and thrombolysis, 2007Co-Authors: Beste Ozben, Reyhan Diz-kucukkaya, Ahmet Kaya Bilge, Veysel Sabri Hancer, Aytac OnculAbstract:Background P-Selectin and P-Selectin Glycoprotein Ligand-1 (PSGL-1) regulate the initial interactions between leukocytes, activated platelets and endothelial cells. Recently, a variable number of tandem repeats (VNTR) polymorphism in PSGL-1 gene affecting the length of the extracellular domain of PSGL-1 and the distance of the P-Selectin binding site to the cell surface has been described. There are limited numbers of studies reporting PSGL-1 polymorphism might affect the inflammatory response and thrombosis. We explored the association between PSGL-1 VNTR polymorphisms (especially AB genotype that has the most deformed configuration of the binding site) and the development of coronary stent restenosis and stent thrombosis in patients with coronary artery disease (CAD).
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Human polymorphism of P-Selectin Glycoprotein ligand 1 attributable to variable numbers of tandem decameric repeats in the mucinlike region.
Blood, 2001Co-Authors: Vahid Afshar-kharghan, Reyhan Diz-kucukkaya, Erwin H. Ludwig, Ali J. Marian, José A. LópezAbstract:Platelet GP Ibα and leukocyte P-Selectin Glycoprotein ligand 1 (PSGL-1) are membrane mucins with a number of structural and functional similarities. It was investigated whether, like GP Ibα, PSGL-1 is affected by a variable number of tandem repeat polymorphism in its mucin-like region. By polymerase chain reaction amplification of the genomic region encoding the PSGL-1 repeats, 3 allelic variants were identified in the human population. The 3 alleles—A, B, and C—from largest to smallest, contained 16, 15, and 14 decameric repeats, respectively, with the B variant lacking repeat 2 and the C variant retaining repeat 2 but lacking repeats 9 and 10. Allele frequencies were highest for the A variant and lowest for the C variant in the 2 populations studied (frequencies of 0.81, 0.17, and 0.02 in white persons and 0.65, 0.35, and 0.00 in Japanese). Thus, PSGL-1 is highly polymorphic and contains a structural polymorphism that potentially indicates functional variation in the human population.
