Spatiotemporal dynamics of DNA damage in cells exposed to mixed beams of ionising radiations
Warsaw Medical Physics Meeting 2015
The goal of this study is to analyse the kinetics of formation and repair of ionising radiation-induced foci (IRIF) in cells exposed to alpha particles, X rays and a mixed beam of both radiations. The hypothesis is that exposure to a mixed beam induces complex DNA damage above the level expected from the additive action of both radiations and the results of this analysis will be presented. The measurements are performed with human cells transfected with a plasmid coding for the DNA repair protein 53BP1 that is tagged with the green fluorescence protein (GFP). Spatiotemporal dynamics of 53BP1 foci formation and repair is recorded by time-lapse photography and image analysis. The results are relevant for the assessment of cancer risk due to exposure to mixed beams as encountered during modern external beam radiotherapy with high energy photons or with protons.
25 minutes 12 seconds