Comprehensive Analysis of Procoagulant Platelets Exhibiting Features of Necrosis, Apoptosis and Platelet Activation

Paresh P Kulkarni1, Keith R McCrae2

  • 1Department of Cardiovascular and Metabolic Sciences, Lerner Research Institute, Cleveland Clinic.

Platelets circulating in the bloodstream are relatively quiescent but become "activated" upon encountering stimulants or "agonists" at the site of blood vessel injury. Proaggregatory and procoagulant platelets represent two distinct populations of activated platelets. While proaggregatory platelets facilitate the cessation of bleeding, or "hemostasis," by forming a plug of platelets clumped together through fibrinogen bridges, procoagulant platelets dramatically accelerate the coagulation cascade, culminating in fibrin clot formation. An interesting aspect of procoagulant platelets is that their morphology exhibits certain features of "necrosis" and "apoptosis." They may thus represent a form of cell death in platelets, albeit with an important role in thrombosis and hemostasis. This article introduces the concept of procoagulant platelets, their relevance to health and disease, and a comparison of existing methods for their analysis. It then provides comprehensive protocols for analyzing procoagulant platelets, investigating the mechanisms of their formation, and assessing their prothrombotic role in facilitating coagulation. The article concludes with a discussion of key steps, limitations, and troubleshooting principles for the described methods.

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