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A Microfluidic Flow Chamber Model for Platelet Transfusion and Hemostasis Measures Platelet Deposition and Fibrin Formation in Real-time
Published on: February 14, 2017
Platelet- and erythrocyte-derived microparticles trigger thrombin generation via factor XIIa
P E J Van Der Meijden1, M Van Schilfgaarde, R Van Oerle
1Laboratory for Clinical Thrombosis and Haemostasis, Department of Internal Medicine, Cardiovascular Research Institute Maastricht, Maastricht University Medical Center, Maastricht, the Netherlands.
Microparticles (MPs) from platelets and erythrocytes initiate blood clotting via factor XII (FXII), independent of tissue factor (TF). Monocyte-derived MPs primarily use TF to trigger coagulation.
Area of Science:
- Hematology
- Biochemistry
- Cell Biology
Background:
- Microparticles (MPs) possess procoagulant properties attributed to phosphatidylserine (PS) and tissue factor (TF) on their surface.
- TF is particularly noted on MPs derived from monocytes.
Purpose of the Study:
- To determine the distinct roles of TF and factor XII (FXII) in initiating coagulation.
- To compare these roles across MPs originating from monocytes, platelets, and erythrocytes.
Main Methods:
- Isolation of MPs from stimulated monocytic THP-1 cells, platelets, and erythrocytes.
- Quantification and characterization of MPs for TF, PS exposure, and thrombin generation potential.
Main Results:
- MPs from platelets and erythrocytes initiate thrombin generation via FXII, independent of TF.
- Monocyte-derived MPs trigger coagulation predominantly through TF.
- TF activity was undetectable on platelet and erythrocyte MPs, but present on monocyte MPs.
Conclusions:
- Platelet and erythrocyte MPs propagate coagulation via PS and initiate thrombin generation through a TF-independent, FXII-dependent pathway.
- Monocyte-derived MPs primarily utilize TF to initiate coagulation.
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