Figure 1

Soluble CD146 enhances the number and proliferation of ECFC colonies isolated from peripheral blood of patients and lowers their onset time. (A) ECFC derived from peripheral blood of patients were characterized by FACS. ECFC display an endothelial phenotype characterized by the expression of CD34, no expression of CD45, and expression of both CD146 and VEGFR2. Plots are representative of 3 independent experiments. (B) The number of ECFC colonies and their time of onset were determined when the isolation procedure was performed in the absence or presence of 50 ng/ml sCD146. The surface area of each colony was also determined at day 25. Results are mean values +/− SEM of 16 independent experiments. (C) Proliferation of ECFC was determined in the absence or presence of sCD146. An anti-sCD146 antibody (M2J-1 mAb) was used to test the specificity of the effect. The results are mean values +/− SEM of 5 independent experiments. (D) The number of tubes was determined in a Matrigel assay when ECFC were incubated in the absence or presence of 50 ng/ml sCD146. Pictures are representative of 10 independent experiments. (E) The number of sprouts, number of branch points and cumulative sprout length were determined in spheroid assays when ECFC were incubated or not in the presence of 50 ng/ml sCD146. Pictures are representative of 10 independent experiments. *P < 0.05, **P < 0.01, ***P < 0.001, experimental vs. Control.