Thrombogenic effect of MRP8/MRP14. (A) After purification of MRP8 and MRP14 from human granulocytes, a sample containing 25 μg purified protein was separated on a 15% SDS gel. (B) In 4 independent experiments, the amount of TSP-1 transcription in control (▦) and MRP8/MRP14-treated HMECs (▪) was determined by quantitative RT-PCR and set in relation to GAPDH expression. Columns represent mean ± SD (^*P < .005). (C) Isolated platelets were stimulated with TRAP (25 μM) and MRP8/MRP14 (200 μg/mL) or were kept in control medium. Binding of FITC-conjugated fibrinogen to platelets was analyzed by flow cytometry. (D) HMEC monolayers were incubated with whole blood under defined shear stress and were assessed for platelet binding. Platelets were identified by specific staining with an FITC-coupled anti-CD41 mAb but could also be visualized on monolayers by phase-contrast microscopy (magnification/numerical aperture of the objective lenses were 20/0.5).