Arrest of 4N1K-activated platelets incubated with blocking mAbs directed against the integrins αIIbβ3, α2β1, and αvβ3 on TNF-α–treated endothelial cells. EA endothelial cells were grown onto permanox Lab-Tek 1 chamber slides and stimulated with 25 ng/mL rhTNF-α for 18 hours. After platelet labeling in PRP with calceine, platelets were incubated for 15 minutes at 37°C with or without 100 μM 4N1K peptide in solution followed by 10-minute incubation at 37°C with 40 μg/mL of either anti-αIIbβ3 mAb P2, anti-α2β1 mAb BHA2.1, or anti-αvβ3 mAb LM609. Whole blood was then reconstituted and perfused through the chamber at 37°C and at a shear rate of 100 seconds–1 for 3 minutes. Platelet adhesion, expressed as percentage of surface covered with platelets, is the average ± SEM of 10 random fields per coverslip. ***P < .001. This experiment is representative of 3 experiments performed with blood from different donors.
