Embryonic hematopoiesis in mice and humans

Aim : The aim of this report is to review briefly the ontogeny of hematopoiesis in mice and humans and to discuss recent evidence for an intraembryonic source of hematopoietic stem cells. Methods : The hematopoiesis overview summarizes information present in the PubMed online database and from experiments conducted in our laboratories. Results : The major sites of hematopoiesis change throughout development in mice and humans. Recent evidence suggests that hematopoietic cells may emerge from mesoderm precursors within the embryo as well as in the yolk sac.
Conclusion : The ontogeny of hematopoiesis is similar in mice and humans. The murine system is a useful model to study the earliest events involved in forming hematopoietic stem cells.