研究了毛细血管扩张性共济失调症(Ataxia-telangiectasia,AT)患者皮肤的成纤维细胞系AT5BIVA(AT细胞)的高辐射敏感性.以源于正常人皮肤的成纤维细胞系GM0639(GM细胞)为对照,利用次黄嘌呤磷酸核糖转移酶基因(Hypoxanthine phospho-ribosyl transferase,hprt)位点突变分析技术及胞质分裂阻滞微核法(Cytokinesis-Block micronucleus method,CBMN),在AT细胞和GM细胞经60Co γ射线0、1、2、3、4Gy照射后,观察比较AT细胞和GM细胞之间hprt基因位点突变频率(hprtMF)、微核率(MNF)及微核细胞率(MNCF)的差异,并分别进行曲线拟合.在各剂量点,AT细胞hprt基因突变频率、微核率及微核细胞率均明显高于GM细胞,其差别具有显著性统计意义(p＜0.01);AT和GM细胞hprt基因突变频率、微核率及微核细胞率均与照射剂量星正相关,可拟合成剂量效应直线方程y=a+bx.结果表明,毛细血管扩张性共济失调症患者AT细胞辐射敏感性显著高于GM细胞,具有高辐射敏感性.
The high radiosensitivity of fibroblast cells (AT5BIVA cells) from the skin of the Ataxia- telangiectasia (A-T) patients were studied. Using Hypoxanthine phospho-ribosyl transferase gene mutation analysis and Cytokinesis-Block micronucleus method, the hprt mutation frequence(hprtMF), the micronucleus frequencies (MNF)and micronucleus cell frequencies (MNCF)of AT and GM cells irradiated with 0, 1, 2, 3 and 4Gy of Co γ-rays 60 were observed. The difference of hprtMF, MNF and MNCF between AT and GM cells were analyzed, and dose-response curves of hprtMF, MNF and MNCF in AT and GM cells were also established. After exposure to 0, 1, 2, 3 and 4Gy of 60Co γ-rays, hprtMF, MNF and MNCF were significantly higher in AT cells than those in GM cells (p<0.01). In the two cell types, hprtMF MNF and MNCF had a positive correlation with dose, and their linear regression equations were y=a+bx. These results show that the radiosensitivity of AT cells is significantly higher than that of GM cells and AT cells are extremely sensitive to radiation.
Journal of Radiation Research and Radiation Processing