适配子功能化金纳米颗粒化学发光定量分析曲霉菌半乳甘露聚糖及其临床应用

The important of Invasive Aspergillosis (IA) in clinical infection is being prominent. The difficult treatment and increasing mortality of IA is partly associated with its hard early diagnosis. Galactomannan (GM) has the early diagnostic value in IA. But the sensitivity and specificity of the current GM detection method,a sandwich ELISA method using monoclonal antibodies, needs to be improved. On the basis of our previous works, this project is expected to select aptamers which bind specifically and selectively to GM and take advantage of the cataluminescence characteristics of gold nanoparticles. Further, a novel chemiluminescence method for GM detection will be developed using GM specific aptamers as molecular recognition and aptamer-functionalized gold nanoparticles as optical signal components. Based on the optimizing and evaluation of the performances of the GM detection method, its effectiveness in the early diagnostic value in IA susceptible herd will also be verified, which will lay a foundation for its application. The project can not only provide a sensitive, specific, rapid and quantitative method for early diagnosis of IA, but also offer available construction technology experiences for other chemiluminescence using aptamer-functionalized gold nanoparticles, which has great practical value and bright prospects.

侵袭性曲霉菌病（IA）在临床感染中的重要性日益突出，其治疗难度大和病死率不断增高与该病难以早期诊断有关。半乳甘露聚糖（GM）具有早期诊断价值，但现有使用单克隆抗体的夹心ELISA检测方法，其敏感性和特异性有待进一步提高。本项目拟在前期工作基础上，筛选高选择性结合GM的核酸适配子，并利用金纳米颗粒液相催化发光的特性，建立以适配子作为GM分子识别，以适配子功能化的金纳米颗粒作为光学信号元件的GM检测新方法；在对该方法各项性能（指标）进行系统评价和优化的基础上，进一步对其在易感人群中早期诊断IA的有效性进行评价和验证，为其推广应用奠定基础。本项目的完成不仅可为临床IA的早期诊断提供灵敏、特异、快速的定量检测方法，有助于临床IA的及时有效治疗，还可为其他基于适配子功能化金纳米颗粒的化学发光检测方法的建立提供可借鉴的技术和经验，具有重要的实用价值和推广应用前景。

侵袭性曲霉菌病(IA)的发病率和病死率逐年增高与IA早期诊断困难有关。半乳甘露聚糖（GM）具有早期诊断价值，但使用单克隆抗体的传统检测方法，其特异性有待提高。本课题筛选了高选择性结合GM的核酸适配子替代抗体，并利用金纳米颗粒液相催化发光的特性，建立了以核酸适配子作为GM分子识别、以适配子功能化的金纳米颗粒作为光学信号元件的GM化学发光检测方法，研究结果证实，这种均相、通用型的GM检测方法兼具检测速度快、特异性好的优点。该方法的灵敏度、交叉反应、特异性、稳定性等方面可以满足临床应用需求，可用于易感人群中早期诊断IA，同时我们还筛选了曲霉菌特异性的适配子并建立了荧光原位杂交新方法方法，在研究中我们还发现了曲霉菌的GM化蛋白磷脂酶C（phospholipase C, PLC）具有潜在的AI诊断价值。相关研究发表SCI论文3篇，申请专利7项，培养博士后2名，博士3名，硕士3名，举办主题学术论坛1次，为推动适配子技术的进步做出了贡献。