<unk> s are the multipotent precursor cells that can differentiate into both hematopoietic and endothelial cells. In the mouse embryo, the emergence of blood islands in the yolk sac at embryonic day 7 marks the onset of hematopoiesis. From these blood islands, the hematopoietic cells and vasculature are formed shortly after.<unk> s are the progenitors that form the blood islands. To date, the<unk>  has been identified in human, mouse and zebrafish embryos.<unk> s have been first extracted from embryonic cultures and manipulated by cytokines to differentiate along either hematopoietic or endothelial route. It has been shown that these pre-endothelial/pre-hematopoietic cells in the embryo arise out of a phenotype CD34 population. It was then found that<unk> s are also present in the tissue of post-natal individuals, such as in newborn infants and adults.
Hemangioblast
Trophoblast
Neural stem cell
Nurse cell
Cytotrophoblast
Syncytiotrophoblast
Clue cell
Progenitor cell