• Embryonic stem cell;
  • Primate;
  • Hemangioblast;
  • Vascular endothelial growth factor


We identified intermediate-stage progenitor cells that have the potential to differentiate into hematopoietic and endothelial lineages from nonhuman primate embryonic stem (ES) cells. Sequential fluorescence-activated cell sorting and immunostaining analyses showed that when ES cells were cultured in an OP9 coculture system, both lineages developed after the emergence of two hemoangiogenic progenitor-bearing cell fractions, namely, vascular endothelial growth factor receptor (VEGFR)-2high CD34 and VEGFR-2high CD34+ cells. Exogenous vascular endothelial growth factor increased the proportion of VEGFR-2high cells, particularly that of VEGFR-2high CD34+ cells, in a dose-dependent manner. Although either population of VEGFR-2high cells could differentiate into primitive and definitive hematopoietic cells (HCs), as well as endothelial cells (ECs), the VEGFR-2high CD34+ cells had greater hemoangiogenic potential. Both lineages developed from VEGFR-2high CD34or VEGFR-2high CD34+ precursor at the single-cell level, which strongly supports the existence of hemangioblasts in these cell fractions. Thus, this culture system allows differentiation into the HC and EC lineages to be defined by surface markers. These observations should facilitate further studies both on early developmental processes and on regeneration therapies in human.