彗星电泳检测^12C^6＋离子束辐照人类肝L02细胞的DNA损伤效应

～(12)C～(6+) Ion Beam Induced DNA Damage in Human Hepatocyte L02 Cells Detected by Comet Assay

以传能线密度为30keV/μm的12C6+离子束辐照人类肝L02细胞,利用彗星电泳技术检测了以DNA链断裂为生物终点的DNA辐射损伤效应。CASP软件分析彗星图像,主要检测尾部DNA(TDNA%)、彗星全长(CL)、尾长(TL)、尾矩(TM)和Olive尾矩(OTM)等指标,SPSS11.5软件进行统计学分析,绘制并拟合TM-剂量曲线。结果显示,辐照以剂量依赖的方式引起L02细胞彗星图像各指标的增大,且TM值与剂量线性正相关。说明12C6+离子束对DNA有较强的致损伤效应,且与剂量正相关。研究为正确评价重离子对人体正常组织的辐射风险及危害提供了一定的基础数据和依据。

Human hepatocyte L02 cells were irradiated by the carbon ion beam with LET of 30 keV/μm and DNA strand breaks were detected immediately after the irradiation using comet assay. Based on the comet images, all the indexes of comet assay including head DNA%, tail DNA%, comet length, tail length, tail moment and olive tail moment were analyzed with CASP and SPSS 11.5 code. Statistically significant dose-effect relationships could be observed in all the indexes of comet assay and TM increased with increasing the radiation dose. These experimental results suggest that carbon ion beam with intermediate LET value would cause remarkable DNA strand breaks immediately and the damage increases in a dose-dependent manner. This work provides basic data and evidence for the risk assessment of heavy ion radiation to healthy tissue.