A standardized and automated CBMN assay for biological dosimetry: the CytoRADx™ system

Major nuclear accidents can result in many casualties, and it is important to assess the absorbed radiation dose to support treatment decisions. Biological dosimetry (BD) allows retrospective determination of dose using biological markers. To achieve consistent cytogenetic assay results across labs, the current practice requires each lab to generate periodic, unique calibration curves using in vitro dose-effect experiments. Here, we present CytoRADx™, a standardized biodosimetry system that integrates automated dose calculation in a high-throughput platform without the need for lab-specific calibration curves. CytoRADx consists of an improved, standardized Cytokinesis Block Micronucleus assay combined with automated analysis utilizing an established slide scanning device. We tested CytoRADx for accuracy and reproducibility across different instruments, sites, days and operators. Our results demonstrate that CytoRADx eliminates the time-consuming, lab-specific calibration curves, allowing multiple laboratories to obtain consistent results and to distribute the testing burden in the event of a large-scale accident.