Ustymenko A. The influence of postnatal thymectomy in CBA/Ca mice on progenitor cells of bone marrow and formation of bone in mature age.

This dissertation was focused on study of the influences of thymectomy in CBA/Ca mice in different age periods (3, 20 and 45 day) and the transplantation of thymus from young and old donors to mice thymectomized on the third day of life on the proliferative potential of stromal, hemopoetic progenitor cells of bone marrow and on the femoral bone density. The thymectomy on the third day of life leads to significant decrease of femoral bone density in mice both sexes, significant increase of colony forming unit of fibroblasts (CFU-F) and unit of granulocyte/macrophage (CFU-GM) as well as to sig-nificant decrease CFU-F/CFU-GM ratio after 3,5 month only. The body mass of mice, the mass of uterus, testis, level of sex hormons (testosterone in males, estradiol in females) and CD4+, CD8+ Т-lymphocyte in bone marrow was significantly decreased, while the mass of adrenal glands showed significant increase. The thymectomy on the third day of life leads to significant decrease of osteocalcin gene expression and functional activity of alkaline phosphatase (AlP) in colony forming unit of osteoblasts (CFU-OB). The functional activity of acid phosphatase (AcP) was significantly increased in colony forming unit of osteoclasts (CFU-OC). The transplantation of thymus from different age donors to thymectomized mice on the third day of life leads to normalization of these parameters.