Effect of BDMPs on platelets. (A) Human platelets incubated with PKH26-labeled BDMPs and a CD61 antibody (10 minutes at 37°C) were gated on CD61 positivity and analyzed for PKH26 fluorescence by flow cytometry (1-way ANOVA, n = 12, *P < .01 compared with baseline). (B) Scanning electron microscopic images of platelets immobilized onto fibrinogen and incubated with either (left) PBS (bar = 1 μm) or (right) BDMPs (bar = 1 μm). (C) Calcium influx in platelets incubated with 25 000/μL BDMPs for the indicated times (n = 6, repeated-measures ANOVA, *P < .001, the values are after background subtraction). (D) CD62p expression was measured on platelets incubated with 25 000/μL BDMPs for 30 minutes at 37°C in the presence and absence of type I collagen (n = 6, paired t test). (E) Annexin V binding to platelets (CD61⁺) treated with BDMPs was measured by flow cytometry (n = 6, 1-way ANOVA, *P < .001 compared with baseline). (F) Human platelets were monitored for aggregation in an optical aggregometer after 25 000/μL BDMPs were added to 100 μL PRP with and without collagen (n = 6, paired t test).