Relationship between uPAR levels and in vitro angiogenesis. (A) Different clones, displaying different levels and distribution of uPAR, evaluated by Western blotting analysis for uPAR and caveolin-1 expression in basal conditions (−VEGF) and after VEGF challenge (+VEGF). Numbers on the right indicate molecular weight. The pictures show the results of a typical experiment of 3 that gave similar results. (B) Matrigel invasion of different ECFC clones in control conditions and in VEGF-stimulated cells. The histograms refer to quantification, expressed as number of migrated cells, of 3 different experiments performed in triplicate with each clone. Results are shown as mean value ± SD. *P < .05, significantly different from control. (C) In vitro capillary morphogenesis of different ECFC clones displaying different uPAR levels. The numbers in the frame represent the percentage of uPAR-positive cells. Histograms on the right show quantification of capillary morphogenesis experiments (under control conditions an VEGF stimulation, respectively). Image acquisition and quantification were performed as reported in Figures 1 and 3. Results are representative of a typical experiment of 3 experiments performed in triplicate with each clone and are quantified by measuring the absolute percentage field occupancy of capillary projections. *P < .05, significantly different from control.