Establishment and validation of surface model for biodosimetry based on γ-H2AX foci detection. (2nd January 2022)

• Record Type: Journal Article
• Authors: López, Juan S.; Pujol-Canadell, Mònica; Puig, Pedro; Ribas, Montserrat; Carrasco, Pablo; Armengol, Gemma; Barquinero, Joan F.
• Is Part Of: International journal of radiation biology. Volume 98:Number 1(2022)
• Page Start: 1
• Page End: 10
• Publication Date: 2022-01-02
• Subjects: γ-H2AX -- biodosimetry -- surface model -- ionizing radiation; Radiation -- Physiological effect -- Periodicals; Radiobiology -- Periodicals; 571.45
• DOI: 10.1080/09553002.2022.1998706
• Languages: English
• ISSNs: 0955-3002

Abstract

Abstract: Introduction: In the event of a radiation accident detecting γ-H2AX foci is being accepted as fast method for triage and dose assessment. However, due to their disappearance kinetics, published calibrations have been constructed at specific post-irradiation times. Objectives: To develop a surface, or tridimensional, model to estimate doses at times not included in the calibration analysis, and to validate it. Materials and methods: Calibration data was obtained irradiating peripheral mononucleated cells from one donor with radiation doses ranging from 0 to 3 Gy, and γ -H2AX foci were detected microscopically using a semi-automatic method, at different post-irradiation times from 0.5 to 24 h. For validation, in addition to the above-mentioned donor, blood samples from another donor were also used. Validation was done within the range of doses and post-irradiation times used in the calibration. Results: The calibration data clearly shows that at each analyzed time, the γ-H2AX foci frequency increases as dose increases, and for each dose this frequency decreases with post-irradiation time. The γ-H2AX foci nucleus distribution was clearly overdispersed, for this reason to obtain bidimensional and tridimensional dose-effect relationships no probability distribution was assumed, and linear and non-linear least squares weighted regression was used. In the two validation exercises for most evaluated samples, the 95% confidence limits of the estimated dose were between ±0.5 Gy of the real dose. No major differences were observed between donors. Conclusion: In case of a suspected overexposure to radiation, the surface model here presented allows a correct dose estimation using γ-H2AX foci as biomarker. The advantage of this surface model is that it can be used at any post-irradiation time, in our model between 0.5 and 24 h.