Adaptive response induced by different dose rates of γ-radiation in MCF-10A cells
(English)Manuscript (preprint) (Other academic)
A phenomenon in which exposure to a low adapting dose of radiation makes cells more resistant to the effects of a subsequent high dose exposure is termed radio-adaptive response. Adaptive response could hypothetically reduce the risk of late adverse effects of chronic or acute radiation exposures in humans. Understanding the underlying mechanisms of such responses are of relevance for radiation protection as well as for the clinical applications of radiation in medicine. However, due to the variability of responses depending on the model system and radiation condition, there is a need to further study under what conditions adaptive response can be induced. In this study, we analyzed if there is a dose rate dependence for the adapting dose, assuming that the adapting dose induces DNA response/repair pathways that are dose rate dependent. MCF-10A cells were exposed to a 50 mGy adapting dose administered acutely (24 Gy/h) or chronically (1.4 or 4.1 mGy/h). After 2 hours incubation time cells were exposed to a challenging dose of 1 to 5 Gy. Adaptive response was absent at the level of clonogenic survival and present at the level of mutations only at 1.4 mGy/h administration of adapting dose. Overall, no dose rate effect of the adapting dose was observed at the level of clonogenic survival, while it was seen at the frequency of mutants. On the other hand, a dose rate effect was absent at the level of mutant frequency.
Adaptive response, low dose rate, ionizing radiation, mutation rate
Research subject Molecular Genetics
IdentifiersURN: urn:nbn:se:su:diva-114310OAI: oai:DiVA.org:su-114310DiVA: diva2:791137