Analysis of the role of von Willebrand factor, platelet glycoprotein VI-, and α2β1-mediated collagen binding in thrombus formation
| Autor: | Barbara Vidal, Yasuaki Shida, Kate Sponagle, David Lillicrap, Ozge Danisment, Carol Hegadorn, Jeffrey Mewburn, David Stegner, Cynthia M. Pruss, Christine Brown, Bredon Crawford, Natalia Rydz, Bernhard Nieswandt |
|---|---|
| Rok vydání: | 2014 |
| Předmět: |
congenital
hereditary and neonatal diseases and abnormalities Immunology Integrin Mutation Missense Platelet Membrane Glycoproteins Platelet membrane glycoprotein Biochemistry Ferric Compounds Thrombosis and Hemostasis Mice Von Willebrand factor Chlorides In vivo hemic and lymphatic diseases von Willebrand Factor Animals Humans Platelet Noxae chemistry.chemical_classification Mice Knockout biology Thrombosis Cell Biology Hematology Molecular biology In vitro Protein Structure Tertiary Disease Models Animal HEK293 Cells chemistry Amino Acid Substitution biology.protein cardiovascular system Collagen GPVI Integrin alpha2beta1 Glycoprotein circulatory and respiratory physiology |
| Zdroj: | Blood. 124(11) |
| ISSN: | 1528-0020 |
| Popis: | Rare missense mutations in the von Willebrand factor (VWF) A3 domain that disrupt collagen binding have been found in patients with a mild bleeding phenotype. However, the analysis of these aberrant VWF-collagen interactions has been limited. Here, we have developed mouse models of collagen-binding mutants and analyzed the function of the A3 domain using comprehensive in vitro and in vivo approaches. Five loss-of-function (p.S1731T, p.W1745C, p.S1783A, p.H1786D, A3 deletion) and 1 gain-of-function (p.L1757A) variants were generated in the mouse VWF complementary DNA. The results of these various assays were consistent, although the magnitude of the effects were different: the gain-of-function (p.L1757A) variant showed consistent enhanced collagen binding whereas the loss-of-function mutants showed variable degrees of functional deficit. We further analyzed the impact of direct platelet-collagen binding by blocking glycoprotein VI (GPVI) and integrin α2β1 in our ferric chloride murine thrombosis model. The inhibition of GPVI demonstrated a comparable functional defect in thrombosis formation to the VWF(-/-) mice whereas α2β1 inhibition demonstrated a milder bleeding phenotype. Furthermore, a delayed and markedly reduced thrombogenic response was still evident in VWF(-/-), GPVI, and α2β1 blocked animals, suggesting that alternative primary hemostatic mechanisms can partially rescue the bleeding phenotype associated with these defects. |
| Databáze: | OpenAIRE |
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