MicroRNA-Based Radiation Biodosimeter (MiRAD)

描述（由申请人提供）：本项目的长期目标是开发一种基于光学的辐射生物剂量计，可以快速（约15分钟）测量血清学microRNA （miRNA）生物标志物的变化，以预测急性辐射综合征（ARS）。MicroRNAs （miRNAs）是短的（18-22碱基）非编码RNA链，通过调节蛋白质表达来控制许多生物过程。暴露于辐射已被证明会改变与ARS相关的miRNA面板的表达，从而确定血清可用于ARS的预测分析。为了测量这些miRNA辐射生物标志物的变化，我们将开发一种基于miRNA的辐射生物剂量计（MiRAD）系统，该系统结合了基于自动磁珠的miRNA靶点筛选和扩增反射干涉分析（ARIA），一种专利的色谱仪技术，可同时对100种miRNA辐射生物标志物进行高灵敏度和特异性定量。在初步研究中，我们已经证明了该装置的新概念及其准确测量卵巢癌血清样品中亚毫摩尔浓度miRNA的能力，比目前的RNA定量平台（如RT-PCR）低100倍。我们使用啮齿动物血浆进行的初步研究还确定了一组mirna对全身照射（WBI）具有剂量和时间依赖性反应，其剂量范围与放射事件发生时的医疗分诊有关。我们在提出的概念验证研究中寻求验证的假设是：(1)通过分析血浆在小鼠模型中确定的miRNA面板可用于临床环境中测量WBI剂量；(2)类似的miRNA面板可用于测量非人灵长类动物和人类的WBI剂量；(3)鉴定出一种独特且剂量敏感的miRNA标记物组合，将导致一种快速的POC血液微芯片检测，用于预测暴露第一周内的ARS，从而指导暴露受试者的分配，以便及时进行医疗干预。

DESCRIPTION (provided by applicant): The broad long-term goal of this project is to develop an optically based radiation biodosimeter that rapidly (~ 15 minutes) measures changes in serological microRNA (miRNA) biomarkers to predict acute radiation syndrome (ARS). MicroRNAs (miRNAs) are short (18-22 base) non- coding RNA strands that control a host of biological processes through regulation of protein expression. Exposure to radiation has been shown to alter expression of a miRNA panels linked with ARS, thereby establishing that serum could be used as a predictive assay for ARS. To measure changes in these miRNA radiation biomarkers, we will develop a MicroRNA-based Radiation Biodosimeter (MiRAD) system, which combines automated magnetic bead based screening for miRNA targets with Amplified Reflectometric Interference Analysis (ARIA), a patented ChromoLogic technology, for highly sensitive and specific quantification of 100s of miRNA radiation biomarkers in parallel. In preliminary studies, we have demonstrated the novel concept of the device and its ability to accurately measure subfemtomolar concentrations of miRNA in ovarian cancer serum samples, 100x less than current RNA quantification platforms such as RT-PCR. Our preliminary studies using rodent plasma also have identified panel of miRNAs with dose and time dependent response to whole body irradiation (WBI), in a dose range relevant to medical triage in case of a radiological event. The hypotheses we seek to validate under the proposed proof-of-concept study are (1) the miRNA panel identified in a murine model through analysis of plasma can be used to measure WBI dose in a clinical setting; (2) a similar miRNA panel can be used to measure WBI dose in nonhuman primates and humans; (3) the resulting identification of a unique and dose-responsive combination of miRNA markers will result in a rapid, POC blood-based microchip assay for anticipating ARS within the first week of exposure, thereby guiding the allocation of exposed subjects for timely medical intervention.