Platelet adhesion to apoptotic HUVEC after blockade of HUVEC receptors. Nonactivated platelets were allowed to adhere to HUVEC treated with staurosporine for 6 hours. Before the adhesion assay, HUVEC were treated with different receptor antagonists. Platelet binding was determined by flow cytometry as described above. The following concentrations were used: 5 μmol/L annexin V, 50 μg/mL RGE and RGD peptides, 30 μg/mL MoAb, and a dilution of 1:250 for polyclonal antibodies. Results are expressed as the mean ± SD of the median fluorescence (FL-1-H) of at least two experiments.