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Abstract The cell culture method originally devised by Stephenson and Axelrad for erythropoietin-dependent erythropoietic colony formation (CFU-E) by mouse cells has been adapted to human marrow. Erythropoietic colonies from human marrow contain between eight and 150 cells and reach maximum growth after 7-9 days of incubation. Progenitors of larger colonies differ from the total pool of human CFU-E in that they have a slower mean sedimentation velocity and a greater erythropoietin requirement. The assay is quantitative and was used to determine the radiation sensitivity of human erythropoietic progenitors. The parameters of the survival curve are: Do = 113 ± 7.8, n = 1.5 ± 0.15.
Tepperman et al. (Fri,) studied this question.