Age-associated reduction of the count and functional activity of stromal precursor cells can be caused by both true reduction

• Published in: Bulletin of experimental biology and medicine Vol. 151; no. 2; p. 210
• Main Authors: Danilova, T.A, Gorskaya, Yu. F, Nesterenko, V.G
• Format: Journal Article
• Language: English
• Published: Springer 01.06.2011
• Subjects: Analysis; Kidneys; Monomolecular films; Transplantation
• ISSN: 0007-4888

The study was carried out on CBA mice using the method of heterotopic transplantation. A fragment of the femoral bone marrow (1/2) or spleen (1/5 of the organ) was transplanted under the renal capsule of a recipient. The following donor-recipient cross-transplantation variants were studied: young[right arrow]young (Y[right arrow]Y), young[right arrow]old (Y[right arrow]O), old[right arrow]old (O[right arrow]O), and old[right arrow]young (O[right arrow]Y). Cell suspensions were prepared from 2-month transplants inoculated in monolayer cultures and the cloning efficiency (ECF-F) of stromal precursor cells (CFC-F) was evaluated. The bone marrow transplant ECF-F and the count of CFC-F in the O[right arrow]O group were 8-fold lower than in the Y[right arrow]Y group. In the O[right arrow]Y group, ECF-F was 3-fold higher than in the O[right arrow]O group, but by 2.5 times lower than in the Y[right arrow]Y group. ECF-F in Y[right arrow]O group was 2-fold lower than in Y[right arrow]Y group. The ECF-F and CFC-F count in spleen transplants in the O[right arrow]O group were 4- and 6-fold lower, respectively, than in Y[right arrow]Y group. However, in O[right arrow]Y group ECF-F was 7-fold higher than in O[right arrow]O group and higher than even in Y[right arrow]Y group. The weight of induced ectopic bone tissue after transplantation of the osteoinductor (fragments of the allogenic urinary bladder mucosa) was 2-fold lower in the O[right arrow]O vs. Y[right arrow]Y group. However, comparison of the ectopic bone tissue weights in different experimental groups showed that osteoinductor activity of the bladder epithelium did not decrease, but increased 3-fold with age (O[right arrow]Y:Y[right arrow]Y). A 5-fold reduction of this proportion in groups where the osteoinductor was transplanted from old donors to old and young recipients (O[right arrow]Y:O[right arrow]O) could be attributed to age-specific reduction of the count of inducible osteogenic precursor cells (IOPC). The data in general suggest that age-specific reduction of the stromal precursor count and functional activity could be caused by the true reduction (exhaustion) of cell pool (bone marrow CFC-F; presumably, IOPC) and by the regulatory effects of the organism (bone marrow and splenic CFC-F, IOPC). These data seem to be significant for understanding of the role of osteogenic stromal precursor cells in the development of age-associated bone tissue defects, for example, senile osteoporosis. Key Words: stromal cells; age-associated changes