Single-Step and Highly Sensitive Imaging of Exosomal PD-L1 through Aptamer-Activated Cascade Primer Exchange Reaction-Generated Branched DNA Nanostructures
作者全名："Li, Xinyu; Li, Xinmin; Cheng, Xiaoxue; Bian, Xintong; Shen, Bo; Ding, Xiaojuan; Ding, Shijia"
作者地址："[Li, Xinyu; Li, Xinmin; Shen, Bo; Ding, Shijia] Chongqing Med Univ, Coll Lab Med, Key Lab Clin Lab Diagnost, Minist Educ, Chongqing 400016, Peoples R China; [Cheng, Xiaoxue; Bian, Xintong] Chongqing Med Univ, Ctr Clin Mol Med Detect, Affiliated Hosp 1, Chongqing 400016, Peoples R China; [Shen, Bo] Chongqing Hosp Tradit Chinese Med, Dept Lab Med, Chongqing 400016, Peoples R China; [Ding, Xiaojuan] Chongqing Med Univ, Affiliated Hosp 2, Dept Lab Med, Chongqing 400016, Peoples R China"
通信作者："Li, XM; Ding, SJ (通讯作者)，Chongqing Med Univ, Coll Lab Med, Key Lab Clin Lab Diagnost, Minist Educ, Chongqing 400016, Peoples R China.; Ding, XJ (通讯作者)，Chongqing Med Univ, Affiliated Hosp 2, Dept Lab Med, Chongqing 400016, Peoples R China."
文献类型：Article; Early Access
关键词：exosomal PD-L1; aptamer; primer exchange reaction; branched DNA nanostructures; in situ imaging
摘要："Exosomal PD-L1 plays a critical role in tumor progress and immunotherapy. However, accurately analyzing exosomal PD-L1 is greatly limited by the small-sized and free-floating nature of exosomes and the few proteins each exosome carries. We described herein a single-step and highly sensitive method, termed aptamer-triggered cascade primer exchange reaction (PER)-generated branched DNA nanostructures, for the quantification and imaging of exosomal PD-L1. The presence of exosomal PD-L1 converted the conformation of the recognition probe, accompanied by the exposure of primer 1. Then, primer 1 actuated the cascade PER, which generated branched DNA nanostructures containing numerous G-quadruplex for binding to thioflavin T (ThT) dye, leading to an amplified fluorescence signal. Profiting from directly growing branched DNA nanostructures on the surface of exosomes, the size of exosomes was enlarged and the movement of exosomes was limited, achieving the imaging of exosomal PD-L1 by conventional optical microscopy in a wash- and label-free fashion. Analyzing exosomal PD-L1 from serum samples of 15 cancer patients and is healthy volunteers demonstrated that this simple strategy could distinguish NSCLC patients from healthy donors with high clinical accuracy. Therefore, the developed assay has great potential as a transformative diagnostic toolkit for cancer detection and immunotherapy monitoring."
基金机构："National Natural Science Foundation of China; Natural Science Foundation of Chongqing, China; Kuanren Talents Program of the Second Affiliated Hospital of Chongqing Medical University; ; ; [cstc2019jcyj-msxmX0179]; [cstc2021jcyj-msxmX0325]; [kryc-yq-2125]"
基金资助正文："Funding This work was funded by financial support from the National Natural Science Foundation of China (81873980, 81902164) , the Natural Science Foundation of Chongqing, China (cstc2019jcyj-msxmX0179, cstc2021jcyj-msxmX0325) , and Kuanren Talents Program of the Second Affiliated Hospital of Chongqing Medical University (kryc-yq-2125) ."