Fig. 2. Cells assayed for migratory behaviour in Dunn chambers. (A) Growth medium (+ 10% FCS) without chemoattractant gradient. (B-D) starvation medium (+ 0.1% FCS). (B) No chemoattractant gradient. (C) Concentration gradient of EGF (15 ng/ml in outer well). (D) Concentration gradient of mut C uPA (10 nM in outer well). (A-D) Cell trajectories over 5 hours (10 median cell trajectories). The start point for each cell is coordinate (0,0); The end point is marked by a closed circle; the chemoattractant source is at the top of plot; axis graduations, distance (µm). Circular histograms show the proportion of cells with migratory direction lying within each 20° interval (chemoattractant source at top of histogram). Cells that migrated less than 20 µm were excluded from analysis. The red arrow represents the mean direction of migration; the green segment represents the 95% confidence interval determined by the Rayleigh test. Displacement shows the percentage of cells that migrate further than 20 µm. Concentration-dependent response for (E) EGF, (F) wt uPA (open circles) and mut C uPA (closed circles). (G) Effect of ß₁-integrin neutralising antibody and mouse IgG antibody on chemotaxis stimulated by 10 nM mut C. More than 40 cells pooled from three to six experiments included in analyses.