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Updated: Jun 15, 2026
13:08
Measurement of Factor V Activity in Human Plasma Using a Microplate Coagulation Assay
Published on: September 9, 2012
Platelet binding and activity of recombinant factor VIIa
Maureane Hoffman1, Dougald M Monroe
1Pathology & Laboratory Medicine Service, Durham VA Medical Center, 508 Fulton St., Durham, NC 27705, USA. maureane.hoffman@med.va.gov
Thrombosis Research
|March 2, 2010
Summary
Recombinant activated Factor VII (FVIIa) treats hemophilia by binding to platelets, a mechanism not fully explained by initial theories. Further research is needed to understand its full hemostatic action.
Area of Science:
- Hematology
- Biochemistry
- Pharmacology
Background:
- Recombinant activated Factor VII (FVIIa) is used to treat hemophilia patients with inhibitors.
- Initial understanding proposed FVIIa enhanced Factor X activation via tissue factor.
- Observed high FVIIa doses for hemostasis challenged this initial mechanism.
Purpose of the Study:
- To investigate the mechanism of action for recombinant FVIIa in hemophilia treatment.
- To explore the role of platelet interactions in FVIIa's bypassing activity.
- To clarify the binding mechanisms of FVIIa to activated platelets.
Main Methods:
- Literature review and analysis of existing data on FVIIa mechanism.
- Examination of proposed FVIIa-platelet binding interactions.
- Discussion of the role of anionic phospholipids and glycoprotein Ib/IX/V complex.
Main Results:
- Evidence suggests platelet surface binding is crucial for FVIIa efficacy.
- FVIIa binding to platelets may involve anionic phospholipids and GPIb/IX/V.
- Current models do not fully account for FVIIa's platelet localization.
Conclusions:
- Platelet binding and activity are increasingly recognized as key to FVIIa's bypassing effect in hemophilia.
- The precise molecular interactions governing FVIIa's platelet localization remain incompletely understood.
- Further investigation is required to elucidate the complete hemostatic mechanism of recombinant FVIIa.
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