Department of Clinical Laboratory, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, 400038, China.
Center for Smart Laboratory and Molecular Medicine, Medical School of Chongqing University, Chongqing, 400044, China.
Anal Chem. 2020 Apr 7;92(7):5411-5418. doi: 10.1021/acs.analchem.0c00141. Epub 2020 Mar 27.
Accurate identification of exosomes plays an essential role in facilitating disease diagnosis and therapies. Herein, we proposed an Aptamer-cholesterol-mediated Proximity Ligation Assay (AcmPLA) for accurate identification of exosomes in a dual-probe strategy, one aptamer probe for recognition of exosomal innate surface protein CD63 and another cholesterol probe for biolipid layer targeting. By integrating a proximity ligation of probes bound with exosomal biomarkers for specific recognition and a rolling circle amplification (RCA) strategy for signal amplification, we have successfully developed an exosomes-surface approach that can perform "AND" logic analysis of dual biomarkers, which not only could be used for exosomes quantification, but also for exosomes tracing. Besides RCA-initiated signal amplification, CD9 antibody-labeled magnetic beads were used to capture exosomes for isolation and secondary signal enrichment. Our approach can achieve specific exosomes isolation and accurate identification and thus could be exploited for broad applications in biological science, biomedical engineering, and personalized medicine.
准确识别外泌体在促进疾病诊断和治疗方面起着至关重要的作用。在此，我们提出了一种适体-胆固醇介导的临近连接分析（AcmPLA）方法，用于在双探针策略中准确识别外泌体，一个适体探针用于识别外泌体先天表面蛋白 CD63，另一个胆固醇探针用于靶向生物脂质层。通过整合与外泌体生物标志物结合的探针的临近连接进行特异性识别，以及滚环扩增（RCA）策略进行信号放大，我们成功开发了一种外泌体表面方法，可以进行双生物标志物的“与”逻辑分析，不仅可用于外泌体定量，还可用于外泌体追踪。除了 RCA 引发的信号放大外，还使用 CD9 抗体标记的磁珠捕获外泌体进行分离和二次信号富集。我们的方法可以实现特异性的外泌体分离和准确识别，因此可以广泛应用于生物科学、生物医学工程和个性化医疗。
