Effects of BMP-4 on Ter119⁺ and CD45⁺ EB cell generation are concentration dependent. Both A3-1 and E14 ES cells were differentiated in various concentrations of BMP-4, and analyzed as in Figure 1. Generation of Ter119⁺ (R3), CD45⁺ (R7), CD34⁺CD31^hi (R5), and CD34⁺ CD31^lo (R6) cells were quantified as % total EB cells. Numbers derived from 2 to 5 independent experiments were averaged and plotted according to the BMP-4 concentration with the corresponding SD (vertical line). Open symbols are results from A3-1 ES cells, and closed symbols are from E14 ES cells. Squares indicate results from serum-free medium, and circles indicate results from 15% FCS-containing medium.