Related Experiment Video
Updated: Aug 23, 2026

Measurement of Factor V Activity in Human Plasma Using a Microplate Coagulation Assay
Published on: September 9, 2012
Factor V Leiden: a disorder of factor V anticoagulant function
Elisabetta Castoldi1, Jan Rosing
1Department of Biochemistry, Cardiovascular Research Institute Maastricht, Maastricht University, 6200 MD Maastricht, The Netherlands.
Purpose Of Review:
Activated protein C (APC) resistance, which is often associated with the factor V R506Q (FV Leiden) mutation, is a common risk factor for venous thrombosis. Study of the mechanism of APC resistance has revealed that coagulation FV stimulates the APC-catalysed inactivation of FVIIIa, and that this anticoagulant function of FV is impaired in FV Leiden. The present review covers the discovery, the physiological significance and the structural requirements of the APC-cofactor activity of FV.
Recent Findings:
Recent in vitro and in vivo experiments indicate that the anticoagulant activity of FV is physiologically relevant and that FV plays a major role in the maintenance of the haemostatic balance. Quantitative and functional defects of the APC-cofactor activity of FV lead to increased thrombin generation and are associated with a prothrombotic state. Although the structural requirements for the expression of the APC-cofactor activity of FV are now beginning to be unravelled, the underlying molecular mechanism remains elusive.
Summary:
The APC-cofactor activity of FV and its impairment in FV Leiden can explain the different thrombosis risks associated with heterozygosity, homozygosity and pseudo-homozygosity for FV Leiden. Elucidation of the molecular mechanism of the anticoagulant function of factor V may provide novel targets for the design of antithrombotic drugs.
Related Concept Videos
Anticoagulant Drugs: Low-Molecular-Weight Heparins
Disorders of Hemostasis
Thromboembolic Disorders
Two factors primarily cause thromboembolic conditions.
Venous Thrombosis III: Interprofessional Care
Venous Thrombosis I: Introduction
Extrinsic and Intrinsic Pathways of Hemostasis
The Extrinsic Pathway
The extrinsic pathway of coagulation is typically initiated by tissue damage that exposes blood to tissue factor (TF), a protein released by the damaged tissue cells outside the blood vessels—this interaction with TF triggers biochemical reactions involving specific clotting factors. The key player here is Factor VII, which forms a...
Clot Retraction and Fibrinolysis

