title: Hemangioblasts and hemopoietic stem cells during ontogeny.
abstract: This review focuses on the emergence of hemopoietic stem cells (HSC) in the embryonic aorta, which was analysed in the avian model. Intraaortic clusters, a characteristic vertebrate anatomical feature, were shown to derive from the splanchnopleural (ventral) mesoderm, which has the potential to give rise to both angioblasts and hemopoietic cells. In contrast, the somitic mesoderm was shown to give rise to angioblasts only. The derivation of hemopoietic progenitors from endothelial cells in the floor of the aorta was followed by means of in vivo labelling experiments. Finally, the expression of gene-encoding transcription factors involved in the emergence of HSC was restricted to the floor of the aorta immediately prior to and during the appearance of intraaortic clusters.
authors.affiliation: Laboratoire d'embryologie cellulaire et moléculaire (UMR 7128), 49bis, av. de la Belle Gabrielle, 94736 Nogent-sur-Marne, France. fdieterlen@college-de-france.fr
authors.forename: Françoise
authors.initials: F
authors.lastname: Dieterlen-Lièvre
authors.forename: Luc
authors.initials: L
authors.lastname: Pardanaud
authors.forename: Karine
authors.initials: K
authors.lastname: Bollerot
authors.forename: Thierry
authors.initials: T
authors.lastname: Jaffredo
mesh_terms: D001011:Aorta / Q000196:embryology; D005314:Embryonic and Fetal Development / Q000502:physiology*; D006410:Hematopoiesis / Q000502:physiology*; D006412:Hematopoietic Stem Cells / Q000166:cytology*; D006801:Humans; D014157:Transcription Factors
chemical_list: D014157:Transcription Factors