Figure 4.

BOEC-adherent neutrophils promote platelet adhesion. (a–e) BOECs with combined incubation with anti-CD46, -CD55, and -CD59 antibodies were exposed to 50% NHS and either calcein-labeled platelets alone (upper channel) or labeled neutrophils and platelets together (lower channel). In this typical experiment, bright neutrophil-platelet aggregates can be observed (original magnification ×4) to develop and increase in size over 6 (a), 12 (b), 20 (c), 30 (d), and 40 minutes (e). Bar = 50 μm. Note: Adhesion of single platelets was not detectable at the detector intensity setting used for these experiments. (f) A higher magnification (original magnification ×20) image shows that aggregates contain both platelets and neutrophils (small and large cells, respectively). Bar = 20 μm. BOECs, blood outgrowth endothelial cells; NHS, normal human serum.