Mk podosome formation requires the activity of the Arp2/3 complex. Cells were spread for 3 hours on 100 μg/ml Horm collagen-coated surfaces fixed and stained for F-actin (green) and WASp (red). The right panel of pictures shows the merge of both channels. The cells were treated with different inhibitors: (A) 0.1% DMSO was used as control for (B) 20 μM CK666, (C) 10 μM blebbistatin, (D) 5 μM GM6001. Scale bars represent 10 μm. Quantification of the effect of the inhibitors on (E) the number of podosomes, (F) cell surface area, and (G) podosomes per μm2 were determined on Horm collagen (red columns) or fibrinogen (black columns). Statistical analysis was done using a 1-way analysis of variance. Asterisk indicates significant difference from the control value with a P value < .05. Error bars indicate ±SEM. Data are representative of 3 experiments.
