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Measurement of Factor V Activity in Human Plasma Using a Microplate Coagulation Assay
Published on: September 9, 2012
Circulating microparticles are elevated in carriers of factor V Leiden.
Anoop K Enjeti1, Lisa F Lincz, Fiona E Scorgie
1Hunter Haematology Research Group, Calvary Mater Newcastle, Edith Street, Waratah, NSW 2298, Australia. Anoop.Enjeti@mater.health.nsw.gov.au
Thrombosis Research
|December 22, 2009
Summary
Elevated microparticles (MPs), particularly from leukocytes, are found in Factor V Leiden mutation carriers. These increased MPs may contribute to thrombosis risk in heterozygotes.
Area of Science:
- Hematology
- Thrombosis Research
- Molecular Genetics
Background:
- Microparticles (MPs) are cell-derived fragments implicated in thrombosis.
- Factor V Leiden (FVL) mutation heterozygotes exhibit variable thrombosis risk.
- The role of circulating MPs in FVL heterozygote thrombosis remains unclear.
Purpose of the Study:
- To investigate if elevated circulating microparticle numbers or procoagulant potential contribute to thrombosis risk in Factor V Leiden heterozygotes.
Main Methods:
- Enumerated circulating platelet, endothelial, and leukocyte MPs via flow cytometry in 45 FVL heterozygotes and controls.
- Assessed procoagulant potential using enzyme-linked immunoassay for prothrombinase activity and dilute Russell Viper venom test.
Main Results:
- FVL heterozygotes showed significantly higher levels of circulating MPs compared to controls (p=0.0021).
- All MP subsets, especially leukocyte-derived MPs (CD45+), were elevated in the FVL group.
- No significant difference in prothrombinase activity or clotting time was observed between groups; MP levels did not correlate with thrombosis history within the FVL cohort.
Conclusions:
- Circulating platelet and leukocyte microparticles are elevated in Factor V Leiden heterozygotes.
- These elevated MPs may be significant contributors to thrombosis risk in carriers of the FVL mutation.
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