Open AccessFerritin‐iron increases killing of Chinese hamster ovary cells by X‐irradiation
Author(s) -
Nelson J. M.,
Stevens R. G.
Publication year - 1992
Publication title -
cell proliferation
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.647
H-Index - 74
eISSN - 1365-2184
pISSN - 0960-7722
DOI - 10.1111/j.1365-2184.1992.tb01461.x
Subject(s) - ferritin , chinese hamster ovary cell , toxicity , clonogenic assay , chemistry , irradiation , ovary , hamster , chinese hamster , biology , andrology , microbiology and biotechnology , cell , in vitro , biochemistry , endocrinology , medicine , receptor , physics , organic chemistry , nuclear physics
. Stationary‐phase Chinese hamster ovary cells were cultured in medium containing ferritin (‐19% iron by weight) added at concentrations ranging from 0 to 128 μ g/ml. One set of cultures was unirradiated, and another set was exposed to 4.0 Gy of X‐ray. Clonogenic cell survival was assessed in each set of cultures. In the absence of added ferritin, 4.0 Gy killed approximately 50% of the cells. In the absence of radiation, ferritin was not toxic at less than 48 μ g/ml; above 48 μ g/ml, toxicity increased with concentration. Apoferritin was not toxic at any concentration tested (up to 1000 μ g/ml). Although 32 μg/ ml ferritin, reflecting only a 3–6 fold increase in iron concentration over normal serum, was not toxic, it reduced the survival of X‐irradiated cells by an additional 75%. These results indicate that a sublethal concentration of ferritin can be a potent radiosensitizer. This suggests the possibility that high body iron stores may increase susceptibility to radiation injury in humans.