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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
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Insights into platelet-based control of coagulation.
Susanne M de Witt1, Remco Verdoold1, Judith M E M Cosemans1
1Department of Biochemistry, Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, Maastricht, The Netherlands.
Thrombosis Research
|May 28, 2014
Summary
Platelets are crucial for blood clot formation and regulation. This review details how platelet proteins and signaling pathways control key steps in coagulation, thrombosis, and hemostasis.
Area of Science:
- Hematology
- Biochemistry
- Molecular Biology
Background:
- The coagulation cascade is a complex process essential for hemostasis and implicated in thrombosis.
- Platelets play pivotal and multifaceted roles in regulating coagulation.
- Understanding platelet procoagulant functions is critical for managing bleeding disorders and thrombotic events.
Purpose of the Study:
- To review the mechanisms by which activated platelets regulate the coagulation system.
- To discuss the involvement of various platelet components in procoagulant functions.
- To elucidate signaling pathways governing platelet-mediated thrombin and fibrin formation and clot retraction.
Main Methods:
- Review of existing literature on platelet function in coagulation.
- Analysis of studies utilizing genetically modified mice.
- Examination of data from pharmacological inhibitor studies.
Main Results:
- Activated platelets expose phosphatidylserine, supporting thrombin generation.
- Platelets facilitate fibrin formation and regulate fibrin clot retraction.
- Common signaling pathways mediate phosphatidylserine exposure, thrombin generation, and fibrin clot retraction in collagen-adhered platelets.
- Prolonged calcium elevation drives thrombin generation, while integrin signaling promotes clot retraction.
- Contact-dependent platelet-platelet interactions primarily utilize the integrin pathway.
Conclusions:
- Platelets are central regulators of coagulation through diverse molecular mechanisms.
- Specific signaling pathways, including calcium elevation and integrin-dependent routes, differentially control platelet procoagulant activities.
- Further research into these pathways can inform therapeutic strategies for coagulation disorders.
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