CD27 marks murine embryonic hematopoietic stem cells and type II prehematopoietic stem cells

To the editor: Cell surface markers of adult hematopoietic stem cells (HSCs) are well established, but fewer markers are available for embryonic HSCs and their immediate precursors (pre-HSCs). HSCs differentiate from hemogenic endothelial cells in the major arteries of the embryo [dorsal aorta,