Apoptotic platelets demonstrate reduced adhesion to collagen and VWF. Washed human platelets (3.0 × 10⁸/mL) resuspended in Tyrode buffer (containing BSA [5 mg/mL]) were incubated with vehicle (DMSO) or ABT-737 (1μM), in the presence or absence of Q-VD-Oph (Q-VD: 50μM) for up to 180 minutes. Treated platelets reconstituted with red blood cells were perfused through (A-B) collagen (2.0 mg/mL)- or (C) VWF (100 μg/mL)-coated microcapillary tubes at 1800 s⁻¹. Platelet adhesion was recorded in real time, for off-line analysis as described in supplemental Methods. (A) Snapshots of adherent platelets after 6-minute perfusion across collagen are representative of 3 independent experiments. (B) Quantification of the number of adherent platelets per field after 30-second perfusion across collagen (mean ± SEM, n = 3). (C) Quantification of the number of adherent platelets per field, after 1-minute perfusion across VWF (mean ± SEM, n = 3). At 45 minutes, the rate of translocation of ABT-737–treated platelets was 2-fold faster than that of vehicle-treated platelets. ns indicates not significant. **P < .01. ***P < .001.