In vitro adhesion assays between peripheral blood PMN cells and EC or FCS-coated plastic wells. EC and FCS-coated plastic wells were treated (▨) or not (▪) with GAS6 (1 μg/mL) for 10 minutes and fluorescein-labeled PMN were then seeded on the wells in the presence and absence of PAF (10−7mol/L). Cell adhesion was assessed after an additional 10 minutes. Relative adhesion shows that PAF strikingly increased PMN adhesion to EC and FCS-coated wells. However, GAS6 significantly inhibited the PAF-driven PMN adhesion to EC, but not that to FCS-coated wells. Moreover, GAS6 did not affect PMN adhesion in the absence of PAF. Results are expressed as relative adhesion (%) and represent the mean ± SD from five experiments. Asterisks mark values that are significantly different from the respective control (P < .05) and 100% relative adhesion (bold horizontal line) corresponds to an absolute adhesion of 16 ± 4 (EC) and 11 ± 2 (FCS-coated wells) cells/microscope field.
