AGING AND HEMATOPOIESIS

Abstract

The proliferative ability of hematopoietic stem cells (HSC) was compared in young and aged mice. Infusion of coisogeneic marrow cures the hematopoietic defect of the W/Wv, a mouse with a recessively inherited defect in stem cells, including HSC. W/Wv were cured with equal frequency by relatively small doses of marrow (5 X 104 nucleated cells, an average of 2–3 “curative” HSC per aliquot) from 3-month-old or 27-month-old +/+ donors. After functioning in the originally cured W/Wv. After functioning in secondary recipients for 16 months, it was, in turn, used to cure still other W/Wv. There was no difference between “old” and “young” bone marrow with respect to the frequency of cure in W/Wv, the duration of cure-or, in regard to marrow from cured W/Wv, the number of nucleated and peroxidase-positive cells per humerus and the number of cells capable of producing spleen colonies in irradiated recipients. Thus, these studies fail to disclose any evidence for a proliferative limiation for old as compared to young HSC.