Radiosensitivity and direction of differentiation of colony-forming cells in the spleen

The radiosensitivity of splenic colony-forming units (CFUs) settling in the bone marrow and spleen does not differ significantly. The value of D₀ for CFUs forming colonies in the spleen varies between 105 and 120 R. D₀ for CFUs forming colonies in bone marrow is 120–135 R. It is postulated that two fractions for CFUs are represented in bone marrow, one radiosensitive, the other radioresistant. In the spleen mainly the radiosensitive fraction of CFUs is found.Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR P. D. Gorizontov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 81, No. 1, pp. 74–76, January, 1976.