Enhanced Hematopoietic Recovery in Irradiated Mice Pretreated with Interleukin-1 (IL-1)

Data in this report compare the number of colony-forming cells (CFC) in bone marrow from irradiated and pre-irradiated C57Bl/6J mice injected with saline or recombinant interleukin-1-alpha (rIL-1). Eight to 12 days after sublethal or lethal irradiation, there were more CFU-E (colony-forming units-erythroid), BFU-E (burst-forming units erythroid), GM-CFC (granulocyte-macrophage colony-forming cells), and day 8 CFU-S (colony-forming units-spleen) in bone marrow from rIL-1 injected mice than from saline injected mice. Prior to irradiation, there was no increase in number of CFC in bone marrow from rIL-1 injected mice. However, as determined by sensitivity to hydroxyurea, rIL-1 injection stimulated GM-CFC into cell cycle. These results demonstrate that rIL-1 injection increases the number of CFC that survive in irradiated mice and may be a consequence of the stimulation of CFC into cell cycle prior to irradiation.