Enhanced CLEC-2–mediated aggregation and secretion in Syk(Y317F) platelets. (A) Representative aggregation and secretion tracings of Syk(Y317F) and WT control platelets stimulated with the indicated concentration of CLEC-2 antibody. (B) P-selectin (left), and JON/A (right) expression after CLEC-2 antibody stimulation. Results are analyzed and presented as described in the legend to Figure 2. MFI, median fluorescence intensities.