[Compensation mechanisms in hemopoietic stem cell pool (CFUs) under the conditions of experimental chronic gamma-irradiation].
The kinetics, proliferation and differentiation potentials of hemopoietic stem cells (CFUs) of bone marrow and spleen were investigated in CBA-line mice in the early period (1-30 days) of chronic gamma-irradiation at a dose rate of 0.16 Gy/day to attain a cumulative dose of 4.8 Gy. The results of the experimental study showed the prevalent maintenance of productivity of granulocytic and erythrocytic hemopoietic cell series within the range of reference values, persistent inhibition of the megakaryocytic series (in terms of all hemopoiesis parameters of interest), more marked suppression of the population of polypotential CFUs in the bone marrow as compared with that in the spleen. The obtained results indicated that the mechanisms of hemopoiesis compensation at stem cell pool level were as follows: the increase in proliferation potency of erythrocytic and in polypotential precursors, the rise in the proportion of granulocytic precursors in the real differentiation potential of CFUs, and the processes of repopulation manifested with different intensity in all stem cell populations under study. For maintenance of the necessary productivity of CFUs in each of hemopoietic cell series, consecutively or simultaneously, several compensatory-adaptive mechanisms are started, which allows the avoidance of a sharp competition between hemopoietic cell series under the conditions of stem cell pool depopulation, and preservation of the hemopoiesis as a whole.
Shibkova
D Z
DZ
Efimova
N V
NV
Akleev
A V
AV
D000818:Animals; D002454:Cell Differentiation; D049109:Cell Proliferation; D003114:Colony-Forming Units Assay; D005720:Gamma Rays; D006410:Hematopoiesis / Q000502:physiology / Q000528:radiation effects*; D006412:Hematopoietic Stem Cells / Q000473:pathology / Q000502:physiology* / Q000528:radiation effects*; D051379:Mice; D008808:Mice, Inbred CBA; D011833:Radiation Injuries, Experimental / Q000473:pathology / Q000503:physiopathology*