title: Fibrillar cellular fibronectin supports efficient platelet aggregation and procoagulant activity.
abstract: The ability of cellular fibronectin, found in the vessel wall in a fibrillar conformation, to regulate platelet functions and trigger thrombus formation remains largely unknown. In this study, we evaluated how parietal cellular fibronectin can modulate platelet responses under flow conditions. A fibrillar network was formed by mechanically stretching immobilised dimeric cellular fibronectin. Perfusion of anticoagulated whole blood over this surface resulted in efficient platelet adhesion and thrombus growth. The initial steps of platelet adhesion and activation, as evidenced by filopodia extension and an increase in intracellular calcium levels (419 ± 29 nmol/l), were dependent on integrins α5β1 and αIIbβ3. Subsequent thrombus growth was mediated by these integrins together with the GPIb-V-IX complex, GPVI and Toll-like receptor 4. The involvement of Toll-like receptor 4 could be conveyed via its binding to the EDA region of cellular fibronectin. Upon thrombus formation, the platelets became procoagulant and generated fibrin as revealed by video-microscopy. This work provides evidence that fibrillar cellular fibronectin is a strong thrombogenic surface which supports efficient platelet adhesion, activation, aggregation and procoagulant activity through the interplay of a series of receptors including integrins α5β1 and αIIbβ3, the GPIb-V-IX complex, GPVI and Toll-like receptor 4.
authors.forename: Eric
authors.initials: E
authors.lastname: Maurer
authors.forename: Mathieu
authors.initials: M
authors.lastname: Schaff
authors.forename: Nicolas
authors.initials: N
authors.lastname: Receveur
authors.forename: Catherine
authors.initials: C
authors.lastname: Bourdon
authors.forename: Luc
authors.initials: L
authors.lastname: Mercier
authors.forename: Bernhard
authors.initials: B
authors.lastname: Nieswandt
authors.forename: Christophe
authors.initials: C
authors.lastname: Dubois
authors.forename: Martine
authors.initials: M
authors.lastname: Jandrot-Perrus
authors.forename: Jacky G
authors.initials: JG
authors.lastname: Goetz
authors.forename: François
authors.initials: F
authors.lastname: Lanza
authors.forename: Christian
authors.initials: C
authors.lastname: Gachet
authors.affiliation: Pierre H. Mangin, UMR_S949, INSERM, Etablissement Français du Sang-Alsace (EFS-Alsace), 10, rue Spielmann, BP 36, F-67065 Strasbourg Cedex, France, Tel.: +33 3 88 21 25 25, Fax: +33 3 88 21 25 21, E-mail: pierre.mangin@efs.sante.fr.
authors.forename: Pierre H
authors.initials: PH
authors.lastname: Mangin
mesh_terms: D000818:Animals; D017304:Annexin A5 / Q000378:metabolism; D001777:Blood Coagulation / Q000502:physiology*; D005109:Extracellular Matrix; D005337:Fibrin / Q000096:biosynthesis; D005347:Fibroblasts; D005353:Fibronectins / Q000737:chemistry / Q000502:physiology*; D055767:Immobilized Proteins; D019012:Integrin beta1 / Q000235:genetics; D016023:Integrins / Q000502:physiology; D056656:Lab-On-A-Chip Devices; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D046210:Microfluidic Analytical Techniques; D008855:Microscopy, Electron, Scanning; D010973:Platelet Adhesiveness; D010974:Platelet Aggregation / Q000502:physiology*; D040201:Platelet Membrane Glycoprotein IIb / Q000235:genetics; D010980:Platelet Membrane Glycoproteins / Q000172:deficiency / Q000235:genetics / Q000502:physiology; D012212:Rheology; D013314:Stress, Mechanical; D051197:Toll-Like Receptor 4 / Q000172:deficiency / Q000235:genetics / Q000502:physiology
chemical_list: D017304:Annexin A5; D005353:Fibronectins; D055767:Immobilized Proteins; D019012:Integrin beta1; D016023:Integrins; D040201:Platelet Membrane Glycoprotein IIb; D010980:Platelet Membrane Glycoproteins; C493487:Tlr4 protein, mouse; D051197:Toll-Like Receptor 4; C098341:platelet membrane glycoprotein VI; D005337:Fibrin
keywords: Platelets; arterial thrombosis; fibronectin; haemostasis