Hematopoietic Stem Cells (HSCs)

Hematopoietic stem cells (HSCs) are defined by their ability to self-renew and to differentiate into all blood cell types. These very rare cells form the basis of bone marrow transplantation for treatment of leukemia and other cancers, and are also a promising cell target for developing gene therapies for treating a broad variety of human diseases. However, development of these important clinical applications of HSCs are greatly hampered by the lack of understanding of the extracellular and intracellular signals that govern their fates and the difficulty in ex vivo expansion of these cells. We quantitate these cells by bone marrow transplantation, monitoring the long- term repopulation of the hematopoietic compartment of lethally irradiated mice. This assay thus requires several months to complete.