Acta Chimica Sinica ›› 2020, Vol. 78 ›› Issue (10): 1076-1081.DOI: 10.6023/A20060235 Previous Articles     Next Articles



赵丽东a, 左鹏a, 尹斌成a,b, 洪成林b, 叶邦策a,c   

  1. a 华东理工大学 生物系统及微分析实验室 生物反应器国家重点实验室 上海 200237;
    b 石河子大学化学化工学院 新疆兵团化工绿色加工重点实验室 石河子 832000;
    c 浙江工业大学药学院 长三角地区绿色制药协同创新中心 杭州 310014
  • 投稿日期:2020-06-14 发布日期:2020-07-28
  • 通讯作者: 尹斌成, 洪成林, 叶邦策;;
  • 基金资助:

A Cell Membrane-Anchored DNA Tetrahedral Sensor for Real-time Monitoring of Exosome Secretion

Zhao Li-Donga, Zuo Penga, Yin Bin-Chenga,b, Hong Chenglinb, Ye Bang-Cea,c   

  1. a Lab of Biosystem and Microanalysis, State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai 200237, China;
    b Key Laboratory for Green Processing of Chemical Engineering of Xinjiang Bingtuan, School of Chemistry and Chemical Engineering, Shihezi University, Shihezi, 832000, China;
    c Collaborative Innovation Center of Yangtze River Delta Region Green Pharmaceuticals, College of Pharmaceutical Sciences, Zhejiang University of Technology, Hangzhou 310014, China
  • Received:2020-06-14 Published:2020-07-28
  • Supported by:
    Project supported by the National Natural Science Foundation of China (Nos. 21822402, 21675052, 31730004).

Exosomes are nanoscale bilayer membrane vesicles actively secreted by cells, which carry abundant cell-specific substances. They can directly reflect the physiological and functional status of the secreting cells and play important roles in intercellular communication, physiological and pathological processes. In this work, we combined membrane modification technique with fluorescence imaging technique and blended CD63 aptamers into a highly stable and universal DNA tetrahedral structure to construct a cell membrane-anchored DNA sensor for real-time monitoring the secretion of exosomes. We designed four functional toes on each vertex of the tetrahedral sensor, respectively. A signal report toe on the top vertex consisted of fluorophore-modified CD63 aptamer, quencher-modified quencher probe(QP) binding part of the CD63 aptamer, and block probe (BP) binding the rest of the CD63 aptamer. The other three extended toes on the vertices were immobilized to the cell membrane by hybridizing with cholesterol-modified anchor probes(AP), which spontaneously incorporated to a lipid bilayer via hydrophobic interaction between the cholesterol moieties and the cellular membrane. In the initial state, the proposed DNA tetrahedral sensor was tethered to membrane with fluorophores quenched by QP and CD63 aptamer blocked by QP and BP. Trigger probes (TP) were add to bind to BP, resulting in the activation of the sensor. Subsequently, CD63 aptamers were specifically bound to the secreted exosomes, leading to the release of QP and concurrent fluorescence restoration of fluorophore. The intensity of the fluorescent signal in cell membrane was proportional to the amount of exosomes captured, thus realizing the real-time monitoring of the exosomes by analysis the changes of the fluorescence intensity. The experimental results showed that the sensor exhibited a good stability and a high capture efficiency for secreted exosomes. This strategy would provide a potentially useful tool for a variety of applications in biomedical research, drug discovery and tissue engineering.

Key words: cell membrane-anchored sensor, DNA tetrahedron, exosome, secretion, real-time monitoring, aptamer