Fig. 2.

Simplified model of HSC emergence through different intermediate endothelial stages in mice and humans. Two major fate decisions precede HSC emergence in a dynamic process. Primitive endothelial cells first acquire an early arterial fate, followed by hemogenic endothelial specification, segregated from mature arterial endothelium. The early arterial endothelium-derived hemogenic endothelium (HE) gives rise to pre-HSCs through a gradual endothelial to hematopoietic transition. All intermediate developmental stages can be segregated based on their functionality and different gene expression and surface marker profiles. The phenotype of the different developmental stages is based on a combination of PSC differentiation, in vivo lineage tracing and single cell transcriptome fate mapping. Figure includes data from references [31, 41–49, 64, 71, 73, 78, 112]