Plasma concentration profiles of PEG-rHuMGDF and rhG-CSF after a single injection in irradiated mice. One hour after irradiation, mice received a single intravenous injection of 80 μg/kg PEG-rHuMGDF (•) or 1,000 μg/kg rhG-CSF (▪). Plasma samples were prepared from blood drawn from mice at the indicated times after injection, and were assayed by sandwich ELISA for each cytokine. Each point represents the mean value from 4 mice.