VE-cadherin expression allows identification of a new class of hematopoietic stem cells within human embryonic liver.
Edification of the human hematopoietic system during development is characterized by the production of waves of hematopoietic cells separated in time, formed in distinct embryonic sites (ie, yolk sac, truncal arteries including the aorta, and placenta). The embryonic liver is a major hematopoietic organ wherein hematopoietic stem cells (HSCs) expand, and the future, adult-type, hematopoietic cell hierarchy becomes established. We report herein the identification of a new, transient, and rare cell population in the human embryonic liver, which coexpresses VE-cadherin, an endothelial marker, CD45, a pan-hematopoietic marker, and CD34, a common endothelial and hematopoietic marker. This population displays an outstanding self-renewal, proliferation, and differentiation potential, as detected by in vitro and in vivo hematopoietic assays compared with its VE-cadherin negative counterpart. Based on VE-cadherin expression, our data demonstrate the existence of 2 phenotypically and functionally separable populations of multipotent HSCs in the human embryo, the VE-cadherin(+) one being more primitive than the VE-cadherin(-) one, and shed a new light on the hierarchical organization of the embryonic liver HSC compartment.
Oberlin
Estelle
E
Inserm, U602, Villejuif, France. estelle.oberlin@inserm.fr
Fleury
Maud
M
Clay
Denis
D
Petit-Cocault
Laurence
L
Candelier
Jean-Jacques
JJ
Mennesson
Benoît
B
Jaffredo
Thierry
T
Souyri
Michèle
M
D000818:Animals; D015703:Antigens, CD / Q000235:genetics / Q000378:metabolism*; D018952:Antigens, CD34 / Q000378:metabolism; D015820:Cadherins / Q000235:genetics / Q000378:metabolism*; D002478:Cells, Cultured; D004622:Embryo, Mammalian / Q000166:cytology / Q000378:metabolism; D053595:Embryonic Stem Cells / Q000166:cytology* / Q000378:metabolism; D005260:Female; D015870:Gene Expression; D006410:Hematopoiesis; D018380:Hematopoietic Stem Cell Transplantation; D006412:Hematopoietic Stem Cells / Q000166:cytology* / Q000378:metabolism; D006413:Hematopoietic System / Q000166:cytology / Q000196:embryology*; D006801:Humans; D017493:Leukocyte Common Antigens / Q000378:metabolism; D008099:Liver / Q000166:cytology* / Q000196:embryology*; D051379:Mice; D016513:Mice, SCID; D011247:Pregnancy; D000099152:Cadherin 5
D015703:Antigens, CD; D018952:Antigens, CD34; D015820:Cadherins; D017493:Leukocyte Common Antigens; D000099152:Cadherin 5