Kinetics of binding of mAbs 10E5, 7E3, and PT25-2 to washed platelets. Washed platelets (2 × 10⁸/mL) were incubated with the Alexa⁴⁸⁸-labeled mAbs at 10 μg/mL for the indicated times, and then the samples were diluted 10-fold with HBMT to slow the reaction and immediately analyzed by flow cytometry. The data were normalized by expressing the results as the percentage of antibody bound at 1 hour, the time required to achieve near-saturating levels of mAb 7E3, the mAb that binds slowest. The blue asterisks above the 10E5 curve indicate the time points at which the binding of PT25-2 differs from that of 10E5, and the red asterisks below the 7E3 curve indicate the time points at which the PT25-2 binding differs from that of 7E3 as judged by P < .05 by analysis of variance, followed by Dunnett's post hoc t tests.