Stem Cells from Donor to the Rescue
Once collected, stem cells are usually infused immediately into the patient, where they migrate to the bone marrow and "settle in" or engraft. Once there, stem cells can repopulate the bloodstream with normal red blood cells and immune cells that "rescue" the patient. For some cancer types, this feat is curative.
Alternatively, stem cells are harvested from a donor source and "cryopreserved," which means they are frozen in liquid nitrogen. At some later time, they are thawed and infused into a patient.