Immobilized fibrinogen activates human platelets through glycoprotein VI.
Fiche publication
Date publication
mai 2018
Journal
Haematologica
Auteurs
Membres identifiés du Cancéropôle Est :
Dr GACHET Christian
Tous les auteurs :
Mangin PH, Onselaer MB, Receveur N, Le Lay N, Hardy AT, Wilson C, Sanchez X, Loyau S, Dupuis A, Babar AK, Miller JL, Philippou H, Hughes CE, Herr AB, Ariëns RA, Mezzano D, Jandrot-Perrus M, Gachet C, Watson SP
Lien Pubmed
Résumé
Glycoprotein VI, a major platelet activation receptor for collagen and fibrin, is considered a particularly promising, safe antithrombotic target. In this study, we show that human glycoprotein VI signals upon platelet adhesion to fibrinogen. Full spreading of human platelets on fibrinogen was abolished in platelets from glycoprotein VI- deficient patients suggesting that fibrinogen activates platelets through glycoprotein VI. While mouse platelets failed to spread on fibrinogen, human-glycoprotein VI-transgenic mouse platelets showed full spreading and increased Ca signaling through the tyrosine kinase Syk. Direct binding of fibrinogen to human glycoprotein VI was shown by surface plasmon resonance and by increased adhesion to fibrinogen of human glycoprotein VI-transfected RBL-2H3 cells relative to mock-transfected cells. Blockade of human glycoprotein VI with the Fab of the monoclonal antibody 9O12 impaired platelet aggregation on preformed platelet aggregates in flowing blood independent of collagen and fibrin exposure. These results demonstrate that human glycoprotein VI binds to immobilized fibrinogen and show that this contributes to platelet spreading and platelet aggregation under flow.
Référence
Haematologica. 2018 May;103(5):898-907