“胞浆蛋白辅助荧光放大”高灵敏检测及荧光成像成纤维细胞活化蛋白

Fibroblast activation protein (FAP) plays a critical role in shaping the microenvironment to promote tumor growth, thus fast, sensitive and accurate detecting the FAP is important to screen early tumor. So far, there are few fluorescent FAP probes have been reported. In conventional fluorescent probes, target signaling occurs in an equivalent reaction ratio, whereas, which are not suitable for bioimaging due to the limited sensitivity. In this project, we will propose a new method that utilizes the hydrophobic cavity of cytoplasmic protein as the fluorescent signal amplifier to capture the biochemical information of FAP. Based on the character of dye that can enhance the fluorescence intensity in cavity of cytoplasmic protein, the sensitive nanoprobe can be used to reveal the important roles of FAP during tumor development. The concept proposed in this project that with the cytoplasmic protein as signal amplifier will give new method for designing fluorescent probe. At the same time, the FAP-detecting platform will provide powerful tools for early diagnosis of other FAP-related diseases.

成纤维细胞活化蛋白在肿瘤发展过程中起着重要推动作用，其快速、灵敏、准确检测对肿瘤早期筛查具有非常重要的意义。目前成纤维细胞活化蛋白响应荧光探针多基于多肽、小分子特异性识别设计，信号为1:1输出模式，但成纤维细胞活化蛋白在肿瘤形成初期低丰度特性，给传统荧光探针生物体内荧光成像带来巨大挑战。本项目以成纤维细胞活化蛋白生物信息获取为目标，针对传统荧光探针灵敏度有限的问题，提出利用胞浆蛋白疏水空腔实现信号放大的新思路。利用信号单元与胞浆蛋白相互作用机制增强荧光信号强度，提高探针灵敏度，探索成纤维细胞活化蛋白在肿瘤不同发展时期作用机制。本项目所提出以胞浆蛋白实现信号放大的策略，为信号放大探针的设计提供了新思路；同时，成纤维细胞活化蛋白高灵敏响应荧光检测平台的构建，将为与之相关多种疾病早期诊断及后期疗效评估提供强有力的工具。

准确获取细胞内低丰度目标物生化信息至关重要，但目前多数基于荧光信号放大策略依赖外部辅助物，在细胞及活体内应用受限。本项目以细胞内高丰度肌动蛋白为信号放大基底，通过染料筛选得到与之相结合荧光增强的荧光体，进一步通过无机纳米颗粒、有机聚合物等负载染料构筑高灵敏监测平台。以多种疾病相关低丰度标志物检测为目的，通过改变纳米载体响应开关，对不同目标物进行高灵敏检测以达到对疾病早期诊断的目的。本项目的执行将为荧光信号放大策略提供新思路，同时，通过研究验证该策略可应用于细胞及活体内相关目标物检测及成像，为探究细胞水平上微量生物活性物质与疾病形成潜在关系提供了强有力的分子工具。