Sensitivity and recovery of stromal progenitor cells (CFU-F) in mouse bone marrow given gamma-irradiation at 0.65 Gy per day.

The sensitivity of stromal progenitor cells (CFU-F) in mouse marrow to whole-body 60Co gamma-irradiation delivered at 0.65 Gy per day, was characterised by a D0 value of about 2.5 Gy up to an accumulated dose of 5 Gy. The cells were less sensitive to higher doses. The rate of recovery following irradiation for 14 days (9.1 Gy) was less than the rate after 30 days irradiation (19.5 Gy). The latter rate of recovery approached that of the stem cells (CFU-S). At 9-10 months after either dose of irradiation, recovery of both CFU-F and CFU-S was incomplete at 30-70% of the aged control.