Thermal sensitivity of haemopoietic and stromal progenitor cells in different proliferative states

Abstract
Stromal progenitor cells (CFU-F) in normal mouse bone marrow were more sensitive to heat at 43 degrees C than haemopoietic progenitor cells (CFU-S and GM-CFC) by a factor of approximately 1.2. In marrow regenerating after 4.5 Gy X-rays, the changes in sensitivity were by less than a factor of 1.4 and the sensitivity of CFU-F changed slightly to become intermediate between that of CFU-S and GM-CFC. A comparison of sensitivities reported in the literature revealed an inexplicable large variation of up to a factor of 6 in the thermal sensitivities of CFU-S and GM-CFC.