Long-term perturbation of hemopoiesis after moderate damage to stem cells.

Hematological indices of BDF1 mice characterizing regeneration in a complex fashion (peripheral cell counts, bone marrow CFU-S, GM-CFU, CFU-F, and the turnover state of bone marrow CFU-S) were followed periodically for 11-14 weeks after 0.5 Gy acute gamma irradiation in order to obtain detailed information about the nonsteady state of murine hemopoiesis after moderate damage to stem cells, demonstrated in our previous experiments. Virtually complete hematological regeneration was followed by long-term increase in the proliferation rate of CFU-S, oscillation in some parameters (granulocyte count, CFU-S level) or an overshooting, sometimes multiwavelike regeneration in others (reticulocyte count, thrombocyte count, and GM-CFU and CFU-F levels). These data suggest a long-term perturbation of hemopoiesis and its environment after moderate damage to the bone marrow.