Production and transmigration of BDMPs. (A) Evans blue leaked from the vasculature of a mouse subjected to FPI, but significantly less from the one with sham surgery (representatives of 3 pairs of mice). (B) A representative image of hippocampal cells that were cultured for 7 days. (C) Cultured hippocampal cells were stimulated with 50 μM of the calcium ionophore A23187. The media collected (upper left) before and (upper right and lower left) after stimulation were analyzed for BDMPs by flow cytometry (n = 6, paired t test, P < .001). (D) HUVECs grown to confluence (left) become retracted and granulated (arrows) after being stimulated with 25 μM histamine (right; bar = 20 μm). (E) PKH26-labeled BDMPs detected in the bottom chamber by flow cytometry 3 hours after BDMPs were incubated with resting and histamine-activated (His) HUVECs in the presence and absence of 3 × 105/μL human live (Pts) or lyophilized (Lyo. Pts) platelets (n = 6/group, 1-way ANOVA, *P < .005 vs baseline). Serotonin (5 μM) also promotes microparticle transmigration in the absence of live platelets. (F) SEM images showing BDMPs (arrowhead) on the opposite side of the membrane from histamine-activated HUVECs that were incubated with BDMPs in the (a) presence and (b) absence of live platelets or (c) resting HUVECs incubated with BDMPs (bar = 5 μm).
