A mechanism to safeguard platelet adhesion under high-shear flow: von Willebrand factor-glycoprotein Ib and integrin α2β1-collagen interactions make complementary, collagen-type-specific contributions to adhesion: reply to a rebuttal

Abstract Abstract 3356 Objective: Multimeric glycoprotein von Willebrand factor (VWF) exhibits a unique triplet structure of individual oligomers, resulting from ADAMTS13 (a disintegrin and metalloproteinase with thrombospondin type 1 motifs 13) cleavage. The faster and slower migrating triplet bands of a given VWF multimer respectively have one shorter or longer N-terminal peptide sequence. Within this peptide sequence, the A1 domain regulates interaction of VWF with platelet glycoprotein (GP)Ib. Distribution of VWF triplet bands is significantly altered in some types of VWD, however, the impact of triplet structure on VWF function has not been investigated so far. Methods: Platelet-adhesive properties of two VWF preparations with similar multimeric distribution but different triplet composition obtained by size exclusion in addition to heparin affinity chromatography were investigated for differential functional activities. Preparation A was enriched in intermediate triplet bands, while preparation B predominantly contained larger triplet bands. Collagen- and GPIb-binding was determined by surface plasmon resonance (SPR). Platelet adhesion under flow was determined using flow-chamber models. Results: Binding studies revealed that preparation A displayed a reduced affinity for recombinant GPIb, but an unchanged affinity for collagen type III, when compared to preparation B. Under high-shear flow conditions, preparation A was less active in recruiting platelets to collagen type III. Furthermore, when added to blood from patients with von Willebrand disease (VWD), defective thrombus formation was less restored. Conclusion: Thus, VWF forms lacking larger size triplet bands appear to have a decreased potential to recruit platelets to collagen-bound VWF under arterial flow conditions. By implication, changes in triplet band distribution observed in patients with VWD may result in altered platelet adhesion at high-shear flow. Disclosures: Schwartz: Octapharma: Employment. Kannicht:Octapharma: Employment. Fuchs:octapharma: Employment. Kröning:octapharma: Employment. Solecka:Octapharma: Employment.

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Thrombospondin‐1 mediates platelet adhesion at high shear via glycoprotein Ib (GPIb): an alternative/backup mechanism to von Willebrand factor

The FASEB Journal ◽

10.1096/fj.02-0830fje ◽

2003 ◽

Vol 17 (11) ◽

pp. 1-18 ◽

Cited By ~ 93

Author(s):

Kerstin Jurk ◽

Kenneth J. Clemetson ◽

Philip G. Groot ◽

Martin F. Brodde ◽

Michael Steiner ◽

...

Keyword(s):

Von Willebrand Factor ◽

Platelet Adhesion ◽

High Shear ◽

Glycoprotein Ib ◽

Thrombospondin 1 ◽

Von Willebrand ◽

Willebrand Factor

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Platelet von Willebrand factor: evidence for its involvement in platelet adhesion to collagen

Blood ◽

10.1182/blood.v70.4.1214.bloodjournal7041214 ◽

1987 ◽

Vol 70 (4) ◽

pp. 1214-1217

Author(s):

E Fressinaud ◽

D Baruch ◽

C Rothschild ◽

HR Baumgartner ◽

D Meyer

Keyword(s):

Shear Rate ◽

Von Willebrand Factor ◽

Platelet Adhesion ◽

Von Willebrand Disease ◽

High Shear ◽

Shear Rates ◽

High Shear Rates ◽

Von Willebrand ◽

Willebrand Factor

Although it is well established that plasma von Willebrand Factor (vWF) is essential to platelet adhesion to subendothelium at high shear rates, the role of platelet vWF is less clear. We studied the respective role of both plasma and platelet vWF in mediating platelet adhesion to fibrillar collagen in a parallel-plate perfusion chamber. Reconstituted blood containing RBCs, various mixtures of labeled washed platelets and plasma from controls or five patients with severe von Willebrand disease (vWD), was perfused through the chamber for five minutes at a shear rate of 1,600 s-1. Platelet-collagen interactions were estimated by counting the radioactivity in deposited platelets and by quantitative morphometry. When the perfusate consisted of normal platelets suspended in normal plasma, platelet deposition on the collagen was 24.7 +/- 3.6 X 10(6)/cm2 (mean +/- SEM, n = 6). Significantly less deposition (16 +/- 2.3) was observed when vWD platelets were substituted for normal platelets. In mixtures containing vWD plasma, significantly greater deposition (9 +/- 2.2) was obtained with normal than with vWD platelets (1 +/- 0.4) demonstrating a role for platelet vWF in mediating the deposition of platelets on collagen. Morphometric analysis confirmed these data. Our findings indicate that platelet, as well as plasma, vWF mediates platelet-collagen interactions at a high shear rate.

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PRIMARY BINDING SITE OF VON WILLEBRAND FACTOR IN THE SUBENDOTHELIUM WHICH MEDIATES PLATELET ADHESION IS NOT COLLAGEN

10.1055/s-0038-1643587 ◽

1987 ◽

Author(s):

Philip G de Groot ◽

Jan A van Mourik ◽

Jan J Sixma

Keyword(s):

Monoclonal Antibody ◽

Von Willebrand Factor ◽

Platelet Adhesion ◽

Collagen Type ◽

Collagen Type I ◽

Extracellular Matrices ◽

Type I ◽

Type Iii ◽

Von Willebrand ◽

Willebrand Factor

We have studies the binding of von Willebrand factor (vWF) to extracellular matrices of endothelial cells and smooth muscle cells and to the vessel wall of human umbilical arteries in relation to its function in supporting platelet adhesion at high shear rates. CLB-RAg 38, a monoclonal antibody directed against vWF inhibits the binding of 125I-vWF extracellular matrices completely. The binding of 125I-vWF to subendothelium is not inhibited, because there are many different binding sites. CLB-RAg 38 inhibits platelet adhesion to extracellular matrices and subendothelium, in sofar as it is dependent on plasma vWF. CLB-RAg 38 has no effect on adhesion depending on vWF already bound to the matrix or subendothelium. CLB-RAg 38 does not inhibit binding of vWF to collagen type I and type III. Another monoclonal antibody against vWF, CLB-RAg 201, completely inhibits binding of vWF to collagen type I and type III. CLB-RAg 201 does not inhibit binding of 125I-vWF ot the extracellular matrices. CLB-RAg 201 partly inhibits platelet adhesion but this inhibition is also present when the adhesion depends on vWF already present in matrix or subendothelium, indicating that CLB-RAg 201 also inhibits the adhesion of platelets directly, this in contrast to CLB-RAg 38. The epitopes for CLB-RAg 201 and 38 were found on different tryptic fragments of vWF. These data indicate that vWF binds to subendothelium and to matrices of cultured cells by mechanism that is different from binding to collagen.

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The functions of the A1A2A3 domains in von Willebrand factor include multimerin 1 binding

Thrombosis and Haemostasis ◽

10.1160/th15-09-0700 ◽

2016 ◽

Vol 116 (07) ◽

pp. 87-95 ◽

Cited By ~ 3

Author(s):

D'Andra Parker ◽

Subia Tasneem ◽

Richard Farndale ◽

Dominique Bihan ◽

J. Sadler ◽

...

Keyword(s):

Endothelial Cells ◽

Von Willebrand Factor ◽

Platelet Adhesion ◽

Structural Features ◽

High Shear ◽

The Individual ◽

Static Conditions ◽

Von Willebrand ◽

Willebrand Factor

SummaryMultimerin 1 (MMRN1) is a massive, homopolymeric protein that is stored in platelets and endothelial cells for activation-induced release. In vitro, MMRN1 binds to the outer surfaces of activated platelets and endothelial cells, the extracellular matrix (including collagen) and von Willebrand factor (VWF) to support platelet adhesive functions. VWF associates with MMRN1 at high shear, not static conditions, suggesting that shear exposes cryptic sites within VWF that support MMRN1 binding. Modified ELISA and surface plasmon resonance were used to study the structural features of VWF that support MMRN1 binding, and determine the affinities for VWF-MMRN1 binding. High shear microfluidic platelet adhesion assays determined the functional consequences for VWF-MMRN1 binding. VWF binding to MMRN1 was enhanced by shear exposure and ristocetin, and required VWF A1A2A3 region, specifically the A1 and A3 domains. VWF A1A2A3 bound to MMRN1 with a physiologically relevant binding affinity (KD: 2.0 ± 0.4 nM), whereas the individual VWF A1 (KD: 39.3 ± 7.7 nM) and A3 domains (KD: 229 ± 114 nM) bound to MMRN1 with lower affinities. VWF A1A2A3 was also sufficient to support the adhesion of resting platelets to MMRN1 at high shear, by a mechanism dependent on VWF-GPIbD binding. Our study provides new information on the molecular basis of MMRN1 binding to VWF, and its role in supporting platelet adhesion at high shear. We propose that at sites of vessel injury, MMRN1 that is released following activation of platelets and endothelial cells, binds to VWF A1A2A3 region to support platelet adhesion at arterial shear rates.

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Platelet adhesion to collagen in healthy volunteers is influenced by variation of both α2β1 density and von Willebrand factor

Blood ◽

10.1182/blood.v96.4.1433 ◽

2000 ◽

Vol 96 (4) ◽

pp. 1433-1437 ◽

Cited By ~ 41

Author(s):

Mark Roest ◽

Jan J. Sixma ◽

Ya-Ping Wu ◽

Martin J. W. Ijsseldijk ◽

Mariëlle Tempelman ◽

...

Keyword(s):

Von Willebrand Factor ◽

Platelet Adhesion ◽

Collagen Type ◽

Normal Subjects ◽

Collagen Type Iv ◽

Collagen Types ◽

Platelet Surface ◽

Type Iv ◽

Von Willebrand ◽

Willebrand Factor

Abstract Platelet thrombus formation on collagen is initiated by platelet GPIb interaction with von Willebrand factor (vWF) bound to collagen, followed by firm attachment of the platelet to collagen by the integrin α2β1. Platelet and plasma vWF levels and α2β1 density on the platelet surface are highly variable among normal subjects; however, little is known about the consequences of this variability on platelet adhesion to collagen. A population of 32 normal subjects was studied to evaluate the relation between genetic and phenotypic variations of α2β1 density on the platelet surface, plasma vWF levels, platelet vWF levels, and adenosine diphosphate and adenosine triphosphate concentrations on the one hand and platelet adhesion to collagen under flow on the other hand. Platelet adhesion to collagen types I and III under flow was correlated with plasma levels of vWF (r2 = 0.45 and 0.42, respectively) and α2β1 density on the platelet surface (r2 = 0.35 and 0.17, not significant). Platelet adhesion to collagen type IV under flow was significantly correlated with platelet vWF levels (r2 = 0.34) and α2β1 density on the platelet surface (r2 = 0.42). Platelet adhesion to collagen types I and III depends on both plasma levels of vWF and α2β1 density on the platelet surface, whereas platelet adhesion to collagen type IV is mediated by both platelet vWF levels and α2β1 density on the platelet surface.

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Von Willebrand factor C1C2 domain is involved in platelet adhesion to polymerized fibrin at high shear rate

Blood ◽

10.1182/blood-2003-07-2267 ◽

2004 ◽

Vol 103 (5) ◽

pp. 1741-1746 ◽

Cited By ~ 25

Author(s):

Jeffrey F. W. Keuren ◽

Dominique Baruch ◽

Paulette Legendre ◽

Cécile V. Denis ◽

Peter J. Lenting ◽

...

Keyword(s):

Shear Rate ◽

Binding Site ◽

Von Willebrand Factor ◽

Platelet Adhesion ◽

Thrombus Formation ◽

High Shear Rate ◽

High Shear ◽

Perfusion Studies ◽

Von Willebrand ◽

Willebrand Factor

AbstractFibrin is actively involved in platelet reactions essential for thrombus growth, in which von Willebrand factor (VWF) might be an important mediator. The aim of this study was to localize VWF domains that bind to fibrin and to determine their relevance in platelet adhesion. VWF binds specifically to fibrin with an apparent Kd of 2.2 μg/mL. Competition in the presence of 2 complementary fragments, SpIII (residues 1-1365) and SpII (residues 1366-2050), indicated that the high affinity binding site for fibrin is located in the C-terminal part, thus distinct from the A domains. Comparison of 2 deleted rVWF (ΔD4B-rVWF, ΔC1C2-rVWF) suggested that the C1C2 domains contained a fibrin binding site. This site is distinct from RGD, as shown by binding of D1746G-rVWF to fibrin. Perfusion studies at high shear rate demonstrated that C1C2 domains were required for optimal platelet adhesion to fibrin. With the use of a VWF-deficient mouse model, it was found that plasma VWF is critical for platelet tethering and adhesion to fibrin. These results suggest a dual role of fibrin-bound VWF in thrombus formation: first, fibrin-bound VWF is critical in the recruitment of platelets by way of glycoprotein (GP) Ib, and, second, it contributes to stationary platelet adhesion by way of binding to activated αIIbβ3.

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Platelet adhesion to collagen in healthy volunteers is influenced by variation of both α2β1 density and von Willebrand factor

Blood ◽

10.1182/blood.v96.4.1433.h8001433_1433_1437 ◽

2000 ◽

Vol 96 (4) ◽

pp. 1433-1437 ◽

Cited By ~ 1

Author(s):

Mark Roest ◽

Jan J. Sixma ◽

Ya-Ping Wu ◽

Martin J. W. Ijsseldijk ◽

Mariëlle Tempelman ◽

...

Keyword(s):

Von Willebrand Factor ◽

Platelet Adhesion ◽

Collagen Type ◽

Normal Subjects ◽

Collagen Type Iv ◽

Collagen Types ◽

Platelet Surface ◽

Type Iv ◽

Von Willebrand ◽

Willebrand Factor

Platelet thrombus formation on collagen is initiated by platelet GPIb interaction with von Willebrand factor (vWF) bound to collagen, followed by firm attachment of the platelet to collagen by the integrin α2β1. Platelet and plasma vWF levels and α2β1 density on the platelet surface are highly variable among normal subjects; however, little is known about the consequences of this variability on platelet adhesion to collagen. A population of 32 normal subjects was studied to evaluate the relation between genetic and phenotypic variations of α2β1 density on the platelet surface, plasma vWF levels, platelet vWF levels, and adenosine diphosphate and adenosine triphosphate concentrations on the one hand and platelet adhesion to collagen under flow on the other hand. Platelet adhesion to collagen types I and III under flow was correlated with plasma levels of vWF (r2 = 0.45 and 0.42, respectively) and α2β1 density on the platelet surface (r2 = 0.35 and 0.17, not significant). Platelet adhesion to collagen type IV under flow was significantly correlated with platelet vWF levels (r2 = 0.34) and α2β1 density on the platelet surface (r2 = 0.42). Platelet adhesion to collagen types I and III depends on both plasma levels of vWF and α2β1 density on the platelet surface, whereas platelet adhesion to collagen type IV is mediated by both platelet vWF levels and α2β1 density on the platelet surface.

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