Fig. 2

Fetal liver endothelium promotes expansion of CD45⁺CD34⁺ cells and multilineage colony-forming progenitors from CD45⁻CD43⁺ cells. A Schematic diagram of CD45⁻CD43⁺ HPCs co-culture with human E4 cardiac endothelial cells (E4CEC) and E4 liver endothelial cells (E4LEC). E4CEC and E4LEC were then separately co-cultured with CD45⁻CD144⁻CD43⁺ fetal liver cells for 10 days. The generated non-adherent cells were collected for phenotypic characterization and colony formation assays. B, C Phenotypic characterization (i) and hematopoietic colony formation (ii) following 10 days of co-culture with E4LEC (B) and E4CEC (C), respectively. Scale bar, 1000 m. D Percentages of CD45⁺CD34⁺ cells assessed by flow cytometry and total cell counts at day 10 were multiplied to quantify absolute numbers of cells at day 10. Bar graph in (i) represents the fold changes of CD45⁺CD34⁺ cells numbers cultured on E4LECs and ECECs relative to E4ECs (n = 3 donors, mean ± SEM, ***p ≤ 0.001). Quantification of (ii) hematopoietic colony-forming progenitors derived from HPCs after co-cultured with different ECs (n = 3 donors, mean ± SEM, **p ≤ 0.01)