Fig. 1. Integrin-induced actin adhesion microspikes are suppressed by PDE4 inhibitors. REF52 cells were trypsinised, washed in serum free media and allowed to adhere to chamber slides that had been coated with laminin (control conditions) in the presence of (A) 0.1% DMSO carrier, (B) 50 µM forskolin, (C) 100 µM IBMX, (D) 1 µM cilostamide, (E) 10 µM rolipram or (F) 5 µM Ro-172420. Cells were fixed 1 hour after plating and stained for vinculin (green) and with TRITC-phalloidin to visualise actin filaments (red). (A) Cells exhibit a dense cortical actin network (dotted arrow) and prominent microspike structures that contain polymerised actin and adhesion proteins (solid arrows). (B,C) Cells exhibit a flattened morphology and extensive lamellipodia/membrane ruffles (arrows). Scale bars, 40 µm.