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Updated: Jun 24, 2025

Measurement of Factor V Activity in Human Plasma Using a Microplate Coagulation Assay
Published on: September 9, 2012
Plasma levels of complement components C5 and C9 are associated with thrombin generation
Rocío Vacik Díaz1, Gaëlle Munsch2, Maria Jesus Iglesias3
1Cardiovascular and Nutrition Research Center Centre de recherche en CardioVasculaire et Nutrition (C2VN), Aix-Marseille University, Institut national de la santé et de la recherche médicale 1263, Institut national de recherche pour l'agriculture, l'alimentation et l'environnement 1260, Marseille, France; Center for Thrombosis and Hemostasis, University Medical Center of the Johannes Gutenberg, Mainz, Germany. Electronic address: https://twitter.com/RocioVacik.
Complement proteins C5 and C9 were identified as novel determinants of thrombin generation. This multiomics study provides insights into hemostatic balance and cardiovascular risk factors.
Area of Science:
- Biochemistry
- Hematology
- Immunology
Background:
- The thrombin generation assay (TGA) assesses plasma's capacity to generate thrombin, reflecting hemostatic balance.
- Understanding factors influencing thrombin generation is crucial for cardiovascular risk assessment.
Purpose of the Study:
- To identify novel biological determinants of thrombin generation using a multiomics approach.
- To investigate the role of complement proteins in hemostasis.
Main Methods:
- Multiomics analysis correlating TGA parameters with plasma protein antibody levels in 770 individuals with venous thrombosis.
- Validation in an independent cohort of 536 healthy individuals.
- Genetic and in vitro experiments on candidate proteins.
Main Results:
- Eighteen proteins associated with TGA parameters, with complement proteins C5 and C9 showing strongest associations in both cohorts.
- Ex vivo C9 supplementation dose-dependently affected TGA parameters.
- A C5 missense variant (rs17611) associated with decreased C5 levels and altered TGA in one cohort.
Conclusions:
- Complement proteins C5 and C9 are identified as potential determinants of thrombin generation.
- Further research is needed to confirm causality and elucidate mechanisms.
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