Figure 2: HaCaT II-4 cultures were grown to confluency, monolayers washed 2X with PBS and incubated in serum-free DMEM for 24 hours. Cultures were scrape-wounded with a P1000 pipette tip using a constant-pressure press, washed 3X to remove liberated cells, and returned to serum-free medium without (control) or with the following additives: EGF (10 ng/mL), PAI-1 (40 mM), RAP (5 μg/mL), or the combination RAP (5 μg/mL) + EGF (10 ng/mL). Initial wound sizes were measured with a calibrated ocular grid at multiple marked sites; 24 hours later, the injury sites were remeasured at the identical marked regions used to calibrate the initial denuded area. The extent of wound site closure (motility index = grid distance migrated) was plotted on the -axis for each condition; shown are data from 2 representative experiments. PAI-1 stimulated cell migration to the same extent as EGF. Ctl: control unstimulated cultures.