Fig. 1. Defective blast-colony formation in the absence of endoglin. (A) Number of BL-CFCs in EBs from Eng^+/+, Eng^+/- and Eng^-/- ES cells on day 3 of differentiation. Error bars indicate standard deviations from three independent experiments performed in duplicate. ^*, P<0.001 versus control (+/+ and +/-). (B) Morphologic aspect of EBs and resulting BL-CFCs in Eng^+/- (upper panels) and Eng^-/- (lower panels) ES cells. (C) Evaluation of the hematopoietic and endothelial potentials of BL-CFCs: individual BL-CFCs were picked, disrupted and replated under the hematopoietic (methylcellulose supplemented with IL-3, IL-6, SCF and EPO) or endothelial (gelatin-coated dishes with VEGF, bFGF, IGF-1 and ECGS) conditions to determine their potential to generate secondary hematopoietic colonies and to form adherent endothelial cells, respectively. The number of colonies that yielded secondary CFCs or adherent endothelial cells and the total number of replated colonies are indicated in parentheses.