Human mammary cell survival following ionizing radiation

Methods of culturing defined stromal and epithelial populations of normal human breast cells have been developed. These cell populations were used to generate radiation dose/survival curves. Survival curves were generated using cells from four donors. The average D0 for epithelial cells was 122 cGy, with an average n value of 2.4. The average D0 and n values for stromal cells were 114 cGy and 2.0. The survival of human breast epithelial cells is compared to that of the cells of the rat mammary gland. The D0 values of both species are essentially the same, while the n value for human epithelial cells is lower. This difference in the n value may be a species specific response to radiation, or may merely reflect a difference in the two assay systems used to generate the survival curves. (author)