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Updated: May 8, 2026

Investigating von Willebrand Factor Pathophysiology Using a Flow Chamber Model of von Willebrand Factor-platelet String Formation
08:30

Investigating von Willebrand Factor Pathophysiology Using a Flow Chamber Model of von Willebrand Factor-platelet String Formation

Published on: August 14, 2017

The interaction between factor H and VWF increases factor H cofactor activity and regulates VWF prothrombotic status

Julie Rayes1, Lubka T Roumenina, Jordan D Dimitrov

  • 1Institut National de la Santé et de la Recherche Médicale.

Blood
|September 10, 2013
PubMed

Vascular endothelial cells (ECs) link hemostasis, thrombosis, and complement. ECs synthesize both the clotting initiator von Willebrand factor (VWF) and the complement regulator factor H (FH). VWF is stored in EC Weibel-Palade bodies (WPBs), but the intracellular location of FH is not well defined. We found that FH colocalizes with VWF in WPBs of human umbilical vein ECs. Moreover, FH bound to VWF with an apparent nanomolar affinity and the complex was present in normal plasma. The binding of VWF to FH enhanced FH cofactor activity toward factor I-mediated downregulation of complement activation. Besides, this interaction inhibited ADAMTS13-mediated proteolysis of VWF and promoted platelet aggregation. Here, we describe a novel interaction between complement and hemostasis. The simultaneous secretion of VWF and FH by activated ECs may promote adhesion of platelets to endothelial injury sites to assure wound healing, simultaneously dampening the proinflammatory effect of complement to limit bystander tissue damage.

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