Pentamidine Is a Specific, Non-Peptide, GPIIb/llla Antagonist

SummaryPentamidine was previously shown to act on glycoprotein (GP) Ilb/IIIa (Cox et al., Thromb Haemost 1992; 68: 731). In this paper we study the effect of pentamidine on other RGD-dependent receptors. In a cell adhesion assay, pentamidine was 500 times more potent than RGDS at inhibiting platelet adhesion to fibrinogen. While RGDS inhibited platelet adhesion to fibronectin, endothelial cell adhesion to vitronectin or fibronectin, 293 cell adhesion to vitronectin, IMR 32 cell adhesion to fibronectin and C32 cell adhesion to vitronectin; pentamidine failed to inhibit these interactions at doses as high as 1 mM. Resting platelets fixed in the presence of 1 mM RGDS had increased binding of fibrinogen, i.e., RGDS activated GPIMIIa, while pentamidine at 100 ΜM had no effect. Similarly, RGDS induced the binding of an anti-LIBS monoclonal antibody, while pentamidine had no effect. Pentamidine partially, but significantly, inhibited lysosome and a-granule release induced by the thrombin agonist peptide, while RGDS had no effect. Neither pentamidine nor RGDS affected ADP-induced Ca2+ influx. Pentamidine had no effect on ADP-induced intracellular pH changes while RGDS prevented the pH from returning to normal. Thus, pentamidine is a non-peptide GPIIb/IIIa antagonist that is non-activating and is specific for GPIIb/IIIa.

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Solid-phase von Willebrand factor contains a conformationally active RGD motif that mediates endothelial cell adhesion through the alpha v beta 3 receptor

Blood ◽

10.1182/blood.v82.12.3622.3622 ◽

1993 ◽

Vol 82 (12) ◽

pp. 3622-3630 ◽

Cited By ~ 23

Author(s):

C Denis ◽

JA Williams ◽

X Lu ◽

D Meyer ◽

D Baruch

Keyword(s):

Monoclonal Antibody ◽

Cell Adhesion ◽

Endothelial Cell ◽

Von Willebrand Factor ◽

Solid Phase ◽

Rgd Sequence ◽

Alpha V Beta 3 ◽

Von Willebrand ◽

Willebrand Factor ◽

Endothelial Cell Adhesion

Abstract The interaction of von Willebrand factor (vWF) with the alpha v beta 3 integrin of human umbilical vein endothelial cells is dependent on the RGD sequence present at residues 1744–1746 of the mature vWF subunit. We compared vWF and its two dimeric fragments, SpIII (residues 1–1365) and SpII (residues 1366–2050), as adhesion substrates. Solid-phase vWF and SpII supported endothelial cell adhesion, whereas SpIII, which contains the glycoprotein (GP) Ib binding domain, did not. Soluble SpII inhibited adhesion to immobilized ligands, whereas soluble vWF did not, suggesting that exposure of the cell attachment domain involves a conformational modification of vWF. Dendroaspin and albolabrin, two RGD- containing peptides of the disintegrin family, were potent inhibitors of cell adhesion to vWF (IC50 approximately 15 nmol/L). Complete inhibition of endothelial cell adhesion to vWF was obtained in the presence of F(ab')2 of monoclonal antibody 9 to vWF, which blocks vWF binding to platelet GPIIb/IIIa. In contrast, monoclonal antibody 713 to vWF, which blocks its binding to platelet GPIb, did not inhibit cell adhesion to vWF. These results indicate that endothelial cell adhesion to vWF is mediated by an RGD-dependent interaction with alpha v beta 3, but does not seem to involve a GPIb-like receptor, and show the importance of the conformation of the RGD sequence.

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p38 Signaling and Receptor Recycling Events in a Microfluidic Endothelial Cell Adhesion Assay

PLoS ONE ◽

10.1371/journal.pone.0065828 ◽

2013 ◽

Vol 8 (6) ◽

pp. e65828 ◽

Cited By ~ 2

Author(s):

Dwayne A. L. Vickers ◽

Emma J. Chory ◽

Megan C. Harless ◽

Shashi K. Murthy

Keyword(s):

Cell Adhesion ◽

Endothelial Cell ◽

Adhesion Assay ◽

Receptor Recycling ◽

Cell Adhesion Assay ◽

Endothelial Cell Adhesion

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Endothelial cell adhesion to soluble vascular endothelial growth factor receptor‐1 triggers a cell dynamic and angiogenic phenotype

The FASEB Journal ◽

10.1096/fj.12-225771 ◽

2013 ◽

Vol 28 (2) ◽

pp. 692-704 ◽

Cited By ~ 10

Author(s):

Angela Orecchia ◽

Amel Mettouchi ◽

Paolo Uva ◽

Glenn C. Simon ◽

Diego Arcelli ◽

...

Keyword(s):

Vascular Endothelial Growth Factor ◽

Cell Adhesion ◽

Endothelial Cell ◽

Growth Factor ◽

Growth Factor Receptor ◽

Vascular Endothelial ◽

A Cell ◽

Endothelial Growth Factor ◽

Endothelial Cell Adhesion

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Collagen-bound LDL modifies endothelial cell adhesion to type V collagen: Implications for atherosclerosis

Open Life Sciences ◽

10.2478/s11535-009-0047-8 ◽

2009 ◽

Vol 4 (4) ◽

pp. 536-542

Author(s):

Stefan Lorkowski ◽

Jürgen Rauterberg ◽

Bärbel Harrach-Ruprecht ◽

David Troyer

Keyword(s):

Cell Adhesion ◽

Endothelial Cell ◽

Arterial Wall ◽

Oxidized Ldl ◽

Density Lipoprotein ◽

Adhesion Assay ◽

Type I ◽

Type V Collagen ◽

Type V ◽

Endothelial Cell Adhesion

AbstractLow density lipoprotein (LDL) is retained in the extracellular matrix of the arterial wall where it is considered to be atherogenic, but little is known about how cell adhesion to the matrix is affected by collagen-bound LDL. We tested the effect of native, oxidized and acetylated LDL reacted with adsorbed monomeric type I, III and V collagen on endothelial cell adhesion to collagen using a colorimetric adhesion assay. We found that none of the LDL species affected adhesion to type I and III collagen, but that collagen-bound native and acetylated LDL enhanced attachment to type V collagen, whereas bound oxidized LDL inhibited adhesion to this collagen. We therefore suggest that oxidized LDL associated with type V collagen in the arterial wall would favor de-endothelialization and contribute to atherogenesis and thrombosis.

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Peptides Derived from Fibronectin Type III Connecting Segments Promote Endothelial Cell Adhesion but Not Platelet Adhesion: Implications in Tissue-Engineered Vascular Grafts

Tissue Engineering ◽

10.1089/ten.2007.0037 ◽

2007 ◽

Vol 13 (11) ◽

pp. 2653-2666 ◽

Cited By ~ 22

Author(s):

Eric J. Rodenberg ◽

Fredrick M. Pavalko

Keyword(s):

Cell Adhesion ◽

Endothelial Cell ◽

Platelet Adhesion ◽

Vascular Grafts ◽

Type Iii ◽

Fibronectin Type Iii ◽

Fibronectin Type ◽

Endothelial Cell Adhesion

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Platelets modulate ischemia/reperfusion-induced leukocyte recruitment in the mesenteric circulation

AJP Gastrointestinal and Liver Physiology ◽

10.1152/ajpgi.2001.281.6.g1432 ◽

2001 ◽

Vol 281 (6) ◽

pp. G1432-G1439 ◽

Cited By ~ 70

Author(s):

James W. Salter ◽

Christian F. Krieglstein ◽

Andrew C. Issekutz ◽

D. Neil Granger

Keyword(s):

Monoclonal Antibody ◽

Cell Adhesion ◽

Endothelial Cell ◽

Ischemia Reperfusion ◽

Leukocyte Recruitment ◽

Leukocyte Adherence ◽

Neutrophil Accumulation ◽

Treatment Groups ◽

Vascular Beds ◽

Endothelial Cell Adhesion

P-selectin-dependent leukocyte-endothelial cell adhesion has been implicated in the pathogenesis of ischemia/reperfusion (I/R) injury in several vascular beds, including the gut. Because platelet-endothelial (P/E) cell adhesion also occurs in postischemic venules, the possibility exists that the expression of P-selectin on the surface of platelets that are adherent to venular endothelial cells may mediate the leukocyte recruitment elicited by I/R. P-selectin expression [dual radiolabeled monoclonal antibody (MAb) technique] and neutrophil accumulation [myeloperoxidase (MPO) activity] were measured in the postischemic small intestine of untreated rats and rats treated with either antiplatelet serum (APS) or MAbs directed against either P-selectin, GPIIb/IIIa, or fibrinogen. The increases in P-selectin expression and tissue MPO normally elicited by I/R were significantly attenuated in the different treatment groups, suggesting that I/R-induced neutrophil recruitment is a platelet-dependent, P-selectin-mediated process. Intravital microscopy was then employed to examine this process relative to leukocyte-endothelial cell adhesion in postischemic rat mesenteric venules. The recruitment of adherent and emigrated leukocytes after I/R was attenuated by pretreatment with a MAb against, either P-selectin, GPIIb/IIIa, or fibrinogen, as well as an Arg-Gly-Asp peptide. Whereas thrombocytopenia greatly blunted leukocyte emigration, it did not alter the leukocyte adherence response to I/R. These findings suggest that platelet-associated P-selectin contributes to the accumulation of leukocytes in postischemic tissue via a mechanism that alters transendothelial leukocyte migration.

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Solid-phase von Willebrand factor contains a conformationally active RGD motif that mediates endothelial cell adhesion through the alpha v beta 3 receptor

Blood ◽

10.1182/blood.v82.12.3622.bloodjournal82123622 ◽

1993 ◽

Vol 82 (12) ◽

pp. 3622-3630 ◽

Cited By ~ 1

Author(s):

C Denis ◽

JA Williams ◽

X Lu ◽

D Meyer ◽

D Baruch

Keyword(s):

Monoclonal Antibody ◽

Cell Adhesion ◽

Endothelial Cell ◽

Von Willebrand Factor ◽

Solid Phase ◽

Rgd Sequence ◽

Alpha V Beta 3 ◽

Von Willebrand ◽

Willebrand Factor ◽

Endothelial Cell Adhesion

The interaction of von Willebrand factor (vWF) with the alpha v beta 3 integrin of human umbilical vein endothelial cells is dependent on the RGD sequence present at residues 1744–1746 of the mature vWF subunit. We compared vWF and its two dimeric fragments, SpIII (residues 1–1365) and SpII (residues 1366–2050), as adhesion substrates. Solid-phase vWF and SpII supported endothelial cell adhesion, whereas SpIII, which contains the glycoprotein (GP) Ib binding domain, did not. Soluble SpII inhibited adhesion to immobilized ligands, whereas soluble vWF did not, suggesting that exposure of the cell attachment domain involves a conformational modification of vWF. Dendroaspin and albolabrin, two RGD- containing peptides of the disintegrin family, were potent inhibitors of cell adhesion to vWF (IC50 approximately 15 nmol/L). Complete inhibition of endothelial cell adhesion to vWF was obtained in the presence of F(ab')2 of monoclonal antibody 9 to vWF, which blocks vWF binding to platelet GPIIb/IIIa. In contrast, monoclonal antibody 713 to vWF, which blocks its binding to platelet GPIb, did not inhibit cell adhesion to vWF. These results indicate that endothelial cell adhesion to vWF is mediated by an RGD-dependent interaction with alpha v beta 3, but does not seem to involve a GPIb-like receptor, and show the importance of the conformation of the RGD sequence.

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