Figure 1. Effect of PI3K inhibitors on S1P- and HDL₃-induced EC migration.

Serum-starved HUVEC were pre-treated with 100 nM wortmannin (A,D), 25 µM LY294002 (B), 5 µM LY294002 (E) or 1 µM AS252424 (C,F) for 30 min. Cell migration induced by S1P (A–C) or HDL₃ (D-F) was determined by Transwell assays. Briefly, cells resuspended in the presence or absence of the specific inhibitor (or vehicle control) were allowed to migrate in the presence of 1 µM S1P or 200 µg/ml HDL₃ in the lower chamber for 4 h. Where necessary, each inhibitor was also added in the lower chamber therefore migration was performed in the continuous presence of the inhibitor to be tested. After 4 h, migrated cells were fixed with 4% paraformaldehyde, stained with 1% crystal violet and counted using a phase-contrast microscopy. Data are expressed as percentage of control (cells untreated and unstimulated) and are means ± SEM from 12 (A), 6 (B), 7 (C), 4 (D), 3 (E) and 5 (F) independent experiments. *p<0.05, **p<0.001.