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10:37
Ferric Chloride-induced Murine Thrombosis Models
Published on: September 5, 2016
Role of thrombospondin in platelet aggregation
The Journal of Clinical Investigation
|November 1, 1984
Summary
Thrombospondin (TSP) binding to fibrinogen on activated platelets is crucial for aggregate stability. Blocking TSP with anti-TSP Fab fragments significantly reduces platelet aggregation and fibrinogen binding, impacting aggregate size and reversibility.
Area of Science:
- Hematology
- Biochemistry
- Cell Biology
Background:
- Thrombospondin (TSP) is a major alpha-granule protein of human platelets.
- TSP binds to activated platelets and forms a complex with fibrinogen.
- The interaction of TSP and fibrinogen may be vital for platelet aggregation.
Purpose of the Study:
- To investigate the role of TSP-fibrinogen interaction in platelet aggregation.
- To determine if anti-TSP Fab fragments can inhibit platelet aggregation and fibrinogen binding.
Main Methods:
- Preparation of monospecific, affinity-purified anti-TSP Fab fragments.
- Assessment of platelet aggregation using turbidometric aggregometry and particle counting.
- Analysis of fibrinogen binding to activated platelets using labeled fibrinogen.
Main Results:
- Anti-TSP Fab significantly inhibited thrombin- and collagen-induced platelet aggregation.
- Anti-TSP Fab reduced platelet macroaggregates and increased microaggregates.
- Anti-TSP Fab decreased fibrinogen binding affinity to activated platelets, suggesting TSP stabilizes fibrinogen interaction.
Conclusions:
- TSP-fibrinogen interaction is important for stabilizing fibrinogen binding to activated platelets.
- TSP plays a key role in reinforcing interplatelet interactions and influencing aggregate size and reversibility.
- Platelet aggregation is a dynamic process where TSP-fibrinogen interaction complements the initial glycoprotein IIb/IIIa-fibrinogen interaction.
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