4-day treatment with BMP-4 followed by 3-day treatment with VEGF induced Ter119⁺ and CD45⁺ EB cells. E14 ES cells were induced to differentiate for 4 days with or without 1.5 ng/mL BMP-4, 10 ng/mL VEGF, or both in the serum-free medium followed by another 3 days in the presence or absence of these factors. Generations of Ter119⁺ erythroid cell and CD45⁺ macrophage progenitors were analyzed by FACScan on day 7. Scatter pattern, gate setting, and staining pattern of the isotype controls were as shown in Figure 1. Note that this series of experiments was performed without SCF. (a) Without factor for 7 days. (b) Without factor for 4 days followed by BMP-4 for 3 days. (c) With BMP-4 for 4 days, then without factor for 3 days. (d) With BMP-4 for 7 days. (e) With BMP-4 for 4 days followed by VEGF for 3 days. (f) With VEGF for 4 days followed by BMP-4 for 3 days. (g) With BMP-4 for 4 days followed by BMP-4 + VEGF for 3 days. (h) With BMP-4 + VEGF for 7 days. Data are displayed as averaged percentage total EB cell population obtained from 4 (for CD45) to 5 (for Ter119) independent experiments with the corresponding SD. Exception: (c) experiments were performed 3 times each.