Fig. 5.
Potential of CD45− TER119−VE-cadherin+ cells to form endothelial cell colonies. VE-cadherin+ 4-integrin−, VE-cadherin+ 4-integrin+, and VE-cadherin− 4-integrin+ cells were sorted from differentiating CCE cells as shown in Fig 3A and cultured on OP9 stromal cell layer for 2 weeks. The cultures were stained in situ with either anti-FLK1 or anti–VE-cadherin MoAbs. (A) Morphology of a FLK1+ endothelial cell colony formed in the culture of VE-cadherin+ 4-integrin+ cells. The bar represents 400 μm. (B) Frequency of cells capable of formation of endothelial cell colony in the indicated fractions. A representative result of three independent experiments is shown.