High FVIII concentrations interfere with GPVI-mediated platelet activation in vitro.

Factor VIII GPVI platelets

Journal

Journal of thrombosis and haemostasis : JTH
ISSN: 1538-7836
Titre abrégé: J Thromb Haemost
Pays: England
ID NLM: 101170508

Informations de publication

Date de publication:
05 Feb 2024
Historique:
received: 15 09 2023
revised: 17 01 2024
accepted: 29 01 2024
medline: 8 2 2024
pubmed: 8 2 2024
entrez: 7 2 2024
Statut: aheadofprint

Résumé

The recruitment of activated FVIII at the surface of activated platelets is a key step towards the burst of thrombin and fibrin generation during thrombus formation at the site of vascular injury. It involves binding to phosphatidyl-serine (PS) and, possibly, to fibrin bound to αIIbβ3. Seminal work had shown the binding of FVIII to resting platelets, yet without a clear understanding of a putative physiological relevance. To characterize the FVIII-platelet interaction and its potential modulation on platelet function. FVIII was incubated with washed platelets. The effects on platelet activation (spontaneously or triggered by collagen and thrombin) were studied by flow cytometry and light transmission aggregometry. We explored the involvement of downstream pathways by studying phosphorylation profiles (western blot). The FVIII-GPVI interaction was investigated by ELISA, confocal microscopy and proximity ligation assay. FVIII bound to the surface of resting and activated platelets in a dose-dependent manner. FVIII at supra-physiological concentrations did not induce platelet activation but rather specifically inhibit collagen-induced platelet aggregation and altered GPVI-dependent phosphorylation. FVIII rid of its chaperon protein, von Willebrand factor (VWF), interacted in close proximity with GPVI at the platelet surface. We showed that VWF-free FVIII binding to, or close to, GPVI modulates platelet activation in vitro. This may represent a yet uncharacterized negative feedback loop to control overt platelet activation. Whether local activated FVIII concentrations achieved during platelet accumulation and thrombus formation at the site vascular injury in vivo are compatible with such a function remains to be determined.

Sections du résumé

BACKGROUND BACKGROUND
The recruitment of activated FVIII at the surface of activated platelets is a key step towards the burst of thrombin and fibrin generation during thrombus formation at the site of vascular injury. It involves binding to phosphatidyl-serine (PS) and, possibly, to fibrin bound to αIIbβ3. Seminal work had shown the binding of FVIII to resting platelets, yet without a clear understanding of a putative physiological relevance.
OBJECTIVES OBJECTIVE
To characterize the FVIII-platelet interaction and its potential modulation on platelet function.
METHODS METHODS
FVIII was incubated with washed platelets. The effects on platelet activation (spontaneously or triggered by collagen and thrombin) were studied by flow cytometry and light transmission aggregometry. We explored the involvement of downstream pathways by studying phosphorylation profiles (western blot). The FVIII-GPVI interaction was investigated by ELISA, confocal microscopy and proximity ligation assay.
RESULTS RESULTS
FVIII bound to the surface of resting and activated platelets in a dose-dependent manner. FVIII at supra-physiological concentrations did not induce platelet activation but rather specifically inhibit collagen-induced platelet aggregation and altered GPVI-dependent phosphorylation. FVIII rid of its chaperon protein, von Willebrand factor (VWF), interacted in close proximity with GPVI at the platelet surface.
CONCLUSIONS CONCLUSIONS
We showed that VWF-free FVIII binding to, or close to, GPVI modulates platelet activation in vitro. This may represent a yet uncharacterized negative feedback loop to control overt platelet activation. Whether local activated FVIII concentrations achieved during platelet accumulation and thrombus formation at the site vascular injury in vivo are compatible with such a function remains to be determined.

Identifiants

DOI: 10.1016/j.jtha.2024.01.021 PMID: 38325597
pubmed: 38325597
pii: S1538-7836(24)00062-X
doi: 10.1016/j.jtha.2024.01.021
pii:
doi:

Types de publication

Journal Article

Langues

eng

Sous-ensembles de citation

IM

Informations de copyright

Copyright © 2024. Published by Elsevier Inc.

Auteurs

Rohini Sekar (R)

Institut National de la Santé et de la Recherche Médicale, Centre de Recherche des Cordeliers, CNRS, Sorbonne Université, Université de Paris, F-75006 Paris, France.

Angelina Mimoun (A)

Institut National de la Santé et de la Recherche Médicale, Centre de Recherche des Cordeliers, CNRS, Sorbonne Université, Université de Paris, F-75006 Paris, France.

Melissa Bou-Jaoudeh (M)

Institut National de la Santé et de la Recherche Médicale, Centre de Recherche des Cordeliers, CNRS, Sorbonne Université, Université de Paris, F-75006 Paris, France.

Stéphane Loyau (S)

Université de Paris, LVTS, Inserm U1148, F-75018 Paris.

Sandrine Delignat (S)

Institut National de la Santé et de la Recherche Médicale, Centre de Recherche des Cordeliers, CNRS, Sorbonne Université, Université de Paris, F-75006 Paris, France.

Victoria Daventure (V)

Institut National de la Santé et de la Recherche Médicale, Centre de Recherche des Cordeliers, CNRS, Sorbonne Université, Université de Paris, F-75006 Paris, France.

Perrine Bonilla (P)

Institut National de la Santé et de la Recherche Médicale, Centre de Recherche des Cordeliers, CNRS, Sorbonne Université, Université de Paris, F-75006 Paris, France.

Aishwarya Sudam Bahle (AS)

Centre for Bio-Separation Technology (CBST), Vellore Institute of Technology (VIT), Vellore, Tamil Nadu, 632014, India.

Krishnan Venkataraman (K)

Centre for Bio-Separation Technology (CBST), Vellore Institute of Technology (VIT), Vellore, Tamil Nadu, 632014, India.

Julie Rayes (J)

Institute of Cardiovascular Sciences, College of Medical and Dental Sciences, University of Birmingham, Birmingham, United Kingdom.

Yacine Boulaftali (Y)

Université de Paris, LVTS, Inserm U1148, F-75018 Paris.

Martine Jandrot-Perrus (M)

Université de Paris, LVTS, Inserm U1148, F-75018 Paris.

Valérie Proulle (V)

Institut National de la Santé et de la Recherche Médicale, Centre de Recherche des Cordeliers, CNRS, Sorbonne Université, Université de Paris, F-75006 Paris, France;; Service d'Hématologie Biologique, Hôpital Cochin, AP-HP.Centre, Paris, France. Electronic address: valerie.proulle@aphp.fr.

Sébastien Lacroix-Desmazes (S)

Institut National de la Santé et de la Recherche Médicale, Centre de Recherche des Cordeliers, CNRS, Sorbonne Université, Université de Paris, F-75006 Paris, France;. Electronic address: sebastien.lacroix-desmazes@inserm.fr.

Classifications MeSH