The Survival of Synchronized L Cells after Ultraviolet Irradiation

Abstract

Survival curves for colony-forming ability of synchronized populations of mouse L cells have been obtained after exposure of the cells to various doses of UVL [ultraviolet light] radiation. The D37 and D0 values of these curves are strongly dependent on the age of the cell in the cell cycle at the time of irradiation, varying at the extremes by a factor of approximately 2. Cells in early S phase are most sensitive; cells in late S or early G2 are least sensitive. These results are in agreement with those of previous workers using different cell lines. The age-dependence of the sensitivity of L cells exposed to UVL radiation was found to be qualitatively and quantitatively different from the age-dependence observed when the same population of cells was exposed to ionizing radiation.