Self-renewal and differentiation capacity of bone marrow and fetal liver stem cells.
An operational definition of the pluripotent stem cell (CFC-S) requires that it have both the capacity for self-renewal and the potential for differentiation into more than one class of formed blood elements. Because the CFC-S compartment is heterogeneous, younger stem cells would be expected to be less committed to differentiation and have a higher rate of self-renewal; whereas, older stem cells would be more committed to differentiation and have a lower rate of self-renewal. In this study, the self-renewal capacity versus the differentiation potential of adult bone marrow and fetal liver stem cells were compared. The self-renewal potential was estimated by determining the number of CFC-S which develop during growth in the spleen of femur of primary recipients. The differentiation potential was estimated by determining the total number of nucleated cells or committed progenitor cells (GM-CFU-C and BFU-E) which develop during growth in the spleen or femur of primary recipients. In order to circumvent possible differences in self-renewal or differentiation pressures due to the presence of differing numbers of CFC-S, an equivalent number of bone marrow and fetal liver CFC-S were allowed to seed the spleen and femur. While both adult bone marrow and fetal liver stem cells showed an extensive capacity for self-renewal, fetal liver CFC-S displayed a greater potential for self-renewal in both the spleen and femur and at all growth intervals measured when compared to adult bone marrow CFC-S. In contrast, no differences were seen in the number of nucleated cells or committed stem cells found per CFC-S when comparing adult bone marrow and fetal liver stem cells.
D000818:Animals; D001854:Bone Marrow Cells; D016026:Bone Marrow Transplantation; D002452:Cell Count; D002454:Cell Differentiation; D003114:Colony-Forming Units Assay; D005260:Female; D006412:Hematopoietic Stem Cells / Q000166:cytology*; D008099:Liver / Q000166:cytology*; D016031:Liver Transplantation; D051379:Mice; D008815:Mice, Inbred Strains; D013154:Spleen / Q000166:cytology; D013997:Time Factors