Stem cell memories may hold answer to their reproduction, study finds
Hematopoietic stem cells (HSCs) are stem cells that reside in bone marrow and are responsible for maintaining the continuous production of blood throughout life. HSCs have been used clinically for decades to treat various blood-borne illnesses ranging from leukemia to severe combined immunodeficiency syndrome. However, a major barrier to treatment is the limited availability of stem cells. Clinicians and researchers have worked to expand stem cell numbers, but have been largely unsuccessful at facilitating reproduction of these cells. This research provides clues as to why these efforts have not succeeded -- because these cells count and retain a memory of their divisions, which control their potential for further reproduction. According to the researchers, the study found that slow cycling cells contained all of the long-term HSC activity among the aging cells in the bone marrow. The data collected further shows that age-related changes to the HSCs, including HSC expansion, are d...