Adult bone marrow cells can differentiate into hemopoietic cells and endothelial cells but not into other lineage cells in normal growth and normal life.

There have been reports that bone marrow cells (BMCs) can differentiate into various cells and tissues and that BMCs improve the function of the injured organs or reduce the organ damage, thereby rescuing the individuals from death. However, these reports also noted that injuries were induced in the organs. Therefore, it is not clear whether BMCs can differentiate into parenchymal cells in organs in normal life or whether BMCs can supply organ-specific stem cells. In this paper, we examine whether adult BMCs could contribute to the development of various organs in normal development after birth and in normal life. BMCs from adult eGFP mice (8 weeks old) were injected into the liver of newborn C57BL/6 mice. The existence of donor-derived cells in various organs was examined 1 year after the injection. In the organs of recipient mice, some of the CD45(+) hemopoietic cells (1.4-13.2%) and CD31(+) endothelial cells (0-2.2%) expressed eGFP, though no other lineage cells did so. These results suggest that adult BMCs can differentiate into not only hemopoietic cells but also vascular endothelial cells, but cannot differentiate into other lineage cells in normal growth and normal life.