Fig. 4

MEIS2 regulates HEP specification and EHT of human early hematopoiesis by targeting TAL1. a Schematic overview of hESC hematopoietic differentiation in chemical defined system. M mesoderm, LM lateral mesoderm, HEP hemogenic endothelial progenitors, HPC hematopoietic progenitor cells. b–d Flow cytometry analysis of BRACH⁺ mesoderm cells (b), APLNR⁺ lateral mesoderm cells (c), and CD31⁺CD34⁺ hemogenic endothelial progenitors (d) generated from WT, MEIS2^+/−, and MEIS2^−/− hESCs at day 1, day 2, and day 4 of differentiation, respectively. e Strategy of assessing the ability of CD31⁺CD34⁺ hemogenic endothelial progenitors to generate CD43⁺ hematopoietic precursors. The emerging CD31⁺CD34⁺ cells generated from WT or MEIS2^−/− hESCs at day 4 were isolated and re-plated into differentiation condition with 40 ng/ml VEGF and 50 ng/ml bFGF and 20 μM SB431542 for 72 h, analyzed with flow cytometry. f Immunofluorescence of CD43⁺ (red) hematopoietic precursors generated from isolated CD31⁺CD34⁺ hemogenic endothelial progenitors. Nuclei were stained with DAPI (blue). g Flow cytometry analysis of CD43⁺ hematopoietic progenitors derived from CD31⁺CD34⁺ cells. Results are shown as means ± SEM (n = 3). NS not significant; *P < 0.05, **P < 0.01, and ***P < 0.001