Hemopoiesis in the splenectomized-pregnant mouse following low-dose total-body irradiation.

The effect of splenectomy (SPLX) and total-body irradiation (TBI) (50-200 rad) on virgin and pregnant mouse hemopoiesis was studied, using peripheral blood hemogram values and femoral marrow hemopoietic progenitor cell activity (i.e., CFUE, BFUE, and GM-CFC). The SPLX-maternal red cell counts and hematocrit values were lower than those of SPLX-virgin mice, reflecting the anemia of pregnancy. But the white cell counts of both SPLX-virgin and SPLX-day-14.5 pregnant mice were significantly higher (P less than 0.005) than normal-virgin mice. Both nonirradiated and day-4 irradiated SPLX-maternal marrow Ep-independent and Ep-dependent CFUE were higher than the nonirradiated and day-4 irradiated SPLX-virgin values (respectively, for each TBI dose studied). On the other hand, nonirradiated and day-4 irradiated SPLX-maternal GM-CFC were lower than the nonirradiated and day-4 irradiated SPLX-virgin GM-CFC values. The data demonstrate the potential of the SPLX-maternal femoral marrow to respond to the stress of low-dose TBI with effective compensatory erythropoiesis, possibly at the expense of granulopoiesis.