Age-Related Decrease in the Number of Stromal Cell Precursors in Bone Marrow and Spleen May Be Due To both Cellular Pool Depletion and Regulatory Impact of the Body

The cloning efficiency (CFE-F) of stromal precursor cells (CFU-F) in cultures of heterotopic transplant cells and the quantity of CFU-F in bone marrow transplants from old donors to old recipients (O-O group) has decreased almost eight times, compared with transplants where the bone marrow from young donors has been transplanted to young recipients (Y-Y group). However, in the O-Y group, the CFE-F and the quantity of CFU-F in the transplants increased more than three times compared with the O-O group, however, staying 2.5 times lower than the Y-Y group level. Regarding transplanting bone marrow from young donors to old recipients (Y-O), the CFE-F of transplants decreased approximately two times lower compared with the CFE-F in the Y-Y group. The CFE-F in the cultures of the spleen transplant cells and the amount of CFUF in the transplants of the O-O group have decreased four and six times, respectively, compared with the Y-Y group. However, if the spleen from the old mice was transplanted to young recipients (O-Y), the CFE-F in transplants was noted to increase almost seven times compared with the CFE-F in spleen transplants from old donors to old recipients (O-O), and exceeded the level of the Y-Y group. These data suggest that the age-related decrease in the CFE-F and the quantity of CFUF in the bone marrow are the results of both changes in the stromal tissue (expressed in real reduction in number of CFU-F), and the regulating action of the organism on stromal tissue. Age-related decrease of CFE-F and the amount of CFU-F in spleen could occur, mainly due to the regulating action of the organism. IJBM 2011; 1(4):221-224. © 2011 International Medical Research and Development Corporation. All rights reserved.