Normal glycoprotein shedding in Scott syndrome platelets with defective PS exposure. Platelets from a healthy control subject or a Scott patient were stimulated with 10 µM ionomycin (A), 10 µM ABT-737 (B), 100 ng/mL convulxin and 4 nM thrombin (C), or 100 µM CCCP (D) at 37°C. GPIbα expression and PS exposure were measured at the indicated time points. Platelets were separated into 4 populations (GPIbαhigh PS−, GPIbαhigh PS+, GPIbαlow PS−, and GPIbαlow PS+) and quantified. Data are means of 3 replicates.