Comparison of Interleukin-1α Gene Expression and Protein Levels in the Murine Spleen after Lethal and Sublethal Total-Body Irradiation

To understand the effects of ionizing radiation on the production of IL-1α in vivo within a hematopoietic organ, we evaluated acute changes in splenic IL-1α mRNA and IL-1α protein after exposing ${\rm B}6{\rm D}2{\rm F}_{1}$ mice to lethal and sublethal 60 Co radiation. Results suggest that in vivo, ionizing radiation induces a time- and dose-dependent accumulation of IL-1α mRNA in the mouse spleen after exposure to γ radiation. Time-dependent increases in the level of IL-1α protein were also observed, although the magnitude of increased protein expression did not complement the magnitude of the accumulation of the message. Selective concentration of cells producing IL-1α does not appear to account completely for the increase in splenic IL-1α mRNA observed in this in vivo system.