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Updated: Jun 28, 2026

Directed Differentiation of Primitive and Definitive Hematopoietic Progenitors from Human Pluripotent Stem Cells
Published on: November 1, 2017
Both primitive and definitive blood cells are derived from Flk-1+ mesoderm
Jesse J Lugus1, Changwon Park, Yunglin D Ma
1Department of Pathology and Immunology, Washington University School of Medicine, St Louis, MO 63110, USA.
Abstract:
Emerging evidence suggests that all hematopoietic and endothelial cells originate from Flk-1(+) mesoderm in the mouse. However, this concept has not been completely proven, especially for the origin of blood cells. Using either Flk1(+/Cre);Rosa26R-EYFP or Flk1(+/Cre);Rosa26R-LacZ mice, we permanently marked Flk-1(+) cells and their progenies to determine the relationship between hematopoietic tissues and cells that express Flk-1. In embryos, all blood cells within the yolk sac and aorta were of Flk-1(+) origin. In addition, nearly all CD45(+) cells in bone marrow and circulating blood in adults were of Flk-1(+) origin. These results provide clear evidence that all blood cells, primitive and definitive, in mice are derived from Flk-1(+) mesodermal cells.
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