Department of Radiation Oncology, University of Rochester School of Medicine and Dentistry, Rochester, NY 14642, USA.
Br J Radiol. 2010 Aug;83(992):694-701. doi: 10.1259/bjr/49886569.
A simple and accurate method for measuring the biological effects of radiation is of increasing importance, especially in mass casualty scenarios. We have therefore developed a new biodosimetric technique targeting circulating B1 DNA in mouse plasma by branched DNA signal amplification for rapid quantification of plasma DNA. This technology targets repetitive elements of the B1 retrotransposon in the mouse genome, followed by signal amplification using Panomics Quantigene 2.0 reagents. Evaluation was conducted concerning precision, accuracy and linearity. Plasma samples were collected from mice 0-24 h after 0-10 Gy total body irradiation (TBI). The average inter- and intra-assay coefficients of variance were 8.7% and 12.3%, respectively. The average recovery rate of spiked DNA into plasma was 89.5%. This assay revealed that when BALB/c and NIH Swiss mice were exposed to 6 Gy TBI, plasma B1 DNA levels increased significantly at 3 h post-TBI, peaked at 9 h and gradually returned toward baseline levels in 24 h. A dose-dependent change in plasma DNA was observed at 9 h post-TBI; the dose-response relation was monotonic, exhibiting linearity for BALB/c mice from 3 to 6 Gy (r = 0.993) and NIH Swiss mice from 3 to 7 Gy (r = 0.98). This branched DNA-based assay is reliable, accurate and sensitive in detecting plasma B1 DNA quantitatively. A radiation dose-correlated increase in plasma B1 DNA was demonstrated in BALB/c and NIH Swiss mice in the dose range from 3 to 6 Gy, suggesting that plasma B1 DNA has potential as a biomarker for radiation biological effect.
一种简单准确的辐射生物效应测量方法变得越来越重要，尤其是在大规模伤亡情况下。因此，我们开发了一种新的生物剂量学技术，通过分支 DNA 信号放大来靶向小鼠血浆中的循环 B1 DNA，从而快速定量血浆 DNA。该技术靶向小鼠基因组中 B1 反转座子的重复元件，然后使用 Panomics Quantigene 2.0 试剂进行信号放大。评估了其精密度、准确性和线性。在接受 0-10 Gy 全身照射（TBI）0-24 小时后，从小鼠中收集血浆样本。平均批内和批间变异系数分别为 8.7%和 12.3%。掺入 DNA 的平均回收率为 89.5%。该检测方法显示，当 BALB/c 和 NIH 瑞士小鼠接受 6 Gy TBI 时，血浆 B1 DNA 水平在 TBI 后 3 小时明显升高，在 9 小时达到峰值，并在 24 小时内逐渐恢复到基线水平。在 TBI 后 9 小时观察到血浆 DNA 的剂量依赖性变化；剂量反应关系是单调的，对于 BALB/c 小鼠从 3 到 6 Gy（r = 0.993）和 NIH 瑞士小鼠从 3 到 7 Gy（r = 0.98）表现出线性。这种基于分支 DNA 的检测方法在定量检测血浆 B1 DNA 方面是可靠、准确和敏感的。在 BALB/c 和 NIH 瑞士小鼠中，从 3 到 6 Gy 的剂量范围内观察到血浆 B1 DNA 与辐射剂量呈相关性增加，表明血浆 B1 DNA 有可能成为辐射生物效应的生物标志物。
