Induction and quantification of γ-H2AX foci following low and high LET-irradiation
Induction and quantification of γ-H2AX foci following low and high LET-irradiation
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DOI：
10.1080/09553000600599783
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发表时间：
2006-02-01
影响因子：
2.6
通讯作者：
O'Neill, P
中科院分区：
文献类型：
--
作者：
Leatherbarrow, EL;Harper, JV;O'Neill, P
目的：利用组蛋白H2 AX的磷酸化，定量研究V79-4和xrs-5中国仓鼠细胞和HF 19人成纤维细胞中DNA双链断裂（DSB）的诱导和重接（γ-H2 AX）作为DSB的指示剂，暴露于低剂量的低线性能量转移（LET）Co-60 γ射线或高LET α粒子。用低或高LET（20 - 2000 mGy）照射细胞。使用免疫组织化学检测γ-H2 AX灶并通过图像分析进行定量。在37 ℃下γ-辐照后30分钟测定的DSB数为12.2（+/- 1.5）、13.5（+/- 1.6）和19.1对于V79-4、xrs- 5和HF 19细胞分别为（+/-1.7）个病灶/细胞/戈伊，与使用脉冲场凝胶电泳在V79-4细胞中检测到的水平相当。γ-照射后6小时，V79-4和HF 19细胞中的γ-H2 AX焦点水平接近对照水平，但在DSB修复缺陷型xrs- 5细胞中保持较高。γ-H2 AX焦点水平仍然显着高于对照组在6 h α-radiated cells.Conclusions：γ-radiation和α-radiation induced the phosphorylation of H2 AX in response to DSB at low doses;在诱导焦点的去磷酸化的速率的变化依赖于辐射质量和细胞特性。
Purpose: To investigate quantitatively the induction and rejoining of DNA double strand breaks (DSB) in V79-4 and xrs-5 Chinese hamster cells and HF19 human fibroblast cells, using the phosphorylation of the histone protein H2AX (gamma-H2AX) as an indicator of DSB, exposed to low doses of either low linear energy transfer (LET) Co-60 gamma-rays or high LET alpha-particles.Materials and methods: Cells were irradiated with low or high LET ( 20 - 2000 mGy). The gamma-H2AX foci were detected using immunohistochemistry and quantified by image analysis.Results: The number of DSB determined 30 min post gamma-irradiation at 37 degrees C is 12.2 (+/- 1.5), 13.5 (+/- 1.6) and 19.1 (+/- 1.7) foci/cell/ Gy for V79-4, xrs- 5 and HF19 cells respectively, comparable with levels detected in V79-4 cells using pulse field gel electrophoresis. 6 h post gamma-irradiation, gamma-H2AX foci levels in V79-4 and HF19 cells approach control levels but remain higher in DSB repair deficient xrs- 5 cells. gamma-H2AX foci levels remain significantly higher than controls at 6 h in alpha-irradiated cells.Conclusions: gamma-radiation and alpha-radiation induced the phosphorylation of H2AX in response to DSB at low doses; the variation in the rate of dephosphorylation of induced foci are dependent both on radiation quality and cell characteristics.