Platelet-associated TF expression. Washed platelets from healthy subjects were left untreated (Control) or stimulated with PAR-1 agonist peptide (PAR-1 a.p.) or TRAP-6 for 15 minutes or 2 hours at 37°C. Samples were then incubated for 15 minutes with saturating concentration of mouse anti–human TF–fluorescein isothiocyanate (American Diagnostica, catalog no 4507CJ) and mouse anti–human CD41-phycoerythrin monoclonal antibodies (Instrumentation Laboratories, catalog no A07781).2 Fluorescein isothiocyanate– and phycoerythrin-conjugated isotype controls were used in all the experiments to quantify the background labeling. TF-positive platelets were determined in 10 000 CD41-positive events per sample. Mean fluorescence intensities (MFI) were calculated from fluorescence histograms for the gated population, and data were analyzed with CellQuest Pro 5.2.1 software (Becton Dickinson). (A-B) Representative fluorescence histograms of 3 independent experiments performed in triplicate. (C-D) The mean value of the results, reported as %MFI ± SD.
