Loss of β3 integrin tyrosine phosphorylation attenuates platelet mass consolidation following vascular injury in vivo. Platelet mass consolidation was monitored by tracking the movement of individual platelets following adhesion to a developing thrombus, as described in Methods. (A) Photomicrographs show representative thrombus from a WT mouse. The panel on the left shows 4 fluorescently labeled platelets within the platelet mass (outlined by the dotted line). The panel on the right shows the region in the left panel outlined by the gray box. The movement of the 4 platelets was tracked over time using image analysis software, and the tracks of each platelet in the image can be seen. (B) The movement of individual WT and diYF platelets during laser-induced thrombus formation is reported as the end displacement (total distance along a straight line from platelet starting point to endpoint). Horizontal line and error bars indicate the mean ± SEM. For WT, n = 78 platelets from 14 thrombi and for diYF n = 43 platelets from 12 thrombi. Statistics were calculated using the Mann-Whitney test.