Clot Contraction Drives the Translocation of Procoagulant Platelets to Thrombus Surface.

Objective- After activation at the site of vascular injury, platelets differentiate into 2 subpopulations, exhibiting either proaggregatory or procoagulant phenotype. Although the functional role of proaggregatory platelets is well established, the physiological significance of procoagulant platelets, the dynamics of their formation, and spatial distribution in thrombus remain elusive. Approach and Results- Using transmission electron microscopy and fluorescence microscopy of arterial thrombi formed in vivo after ferric chloride-induced injury of carotid artery or mechanical injury of abdominal aorta in mice, we demonstrate that procoagulant platelets are located at the periphery of the formed thrombi.