The group of Professor Hiromitsu Nakauchi of the Institute of Stem Cell Biology and Regenerative Medicine, Stanford University School of Medicine, and Mr. Rei Yamamoto of Stanford University, in the field of stem cell therapy, Center for Stem Cell Therapy, Institute of Medical Science, University of Tokyo, Clarified.Hematopoietic stem cells lose their ability to differentiate into lymphocytes with age, but their self-renewal ability is relatively maintained, and long-term observations have revealed that the changes are reversible.
Hematopoietic stem cells in the bone marrow supply all blood cells (red blood cells, platelets, etc.) in the body for the rest of their lives.So far, it has not been clarified how hematopoietic stem cells change with age.
The collaborative team compared the ability at the single-cell level in vivo by collecting hematopoietic stem cell fractions from the bone marrow of young and aged mice and performing single-cell transplantation.As a result, it was found that the proportion and number of cells in the hematopoietic stem cell fraction that lost the ability to differentiate into lymphocytes but maintained the self-renewal ability increased with aging.Furthermore, when the bone marrow cells were secondarily transplanted and observed for a long period of time, the ability to differentiate into lymphocytes was confirmed again.Hematopoietic stem cells with such properties were not observed in the bone marrow of young mice and were specific to aged mice.
This study suggests that age-related hematopoietic stem cells exhibit specific properties and that stem cell aging, which was previously thought to be irreversible, is reversible in terms of lymphocyte-producing ability. ..Clarifying these mechanisms is expected to lead to "rejuvenation" of blood cell functions such as immunity, elucidation of new aging mechanisms, and investigation of the causes of leukemia onset.
Paper information:[Cell Stem Cell] Large-scale clonal analysis resolves aging of the mouse hematopoietic stem cell compartment
