State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, Nanjing, China.
J Cell Physiol. 2013 Jul;228(7):1487-95. doi: 10.1002/jcp.24304.
Cells release exosomes into extracellular medium. Although the important roles of exosomes in many physiological and pathological processes are being revealed, the mechanism of exosome-cell interaction remains unclear. In this article, employing real-time fluorescence microscopy, the motion of exosomes on the plasma membrane or in the cytoplasm of recipient PC12 cells was observed directly. In addition, several motion modes of exosomes were revealed by single particle tracking (SPT). The changes between motion modes were also detected, presenting the dynamic courses of exosome attachment onto plasma membrane and exosome uptake. Octadecyl rhodamine B chloride (R18) was found to be useful to distinguish endocytosis from fusion during exosome uptake. Colocalization with organelle markers showed exosomes were sorted to acidic vesicles after internalization. The results provide new sight into the exosome-cell interaction mode and the intercellular trafficking of exosomes. This study will help to understand the roles of exosomes at cell level.
细胞将外泌体释放到细胞外介质中。尽管外泌体在许多生理和病理过程中的重要作用正在被揭示，但外泌体与细胞相互作用的机制仍不清楚。在本文中，我们采用实时荧光显微镜直接观察外泌体在受者 PC12 细胞的质膜或细胞质上的运动。此外，我们通过单颗粒跟踪（SPT）揭示了几种外泌体的运动模式。还检测到运动模式之间的变化，呈现出外泌体附着到质膜和外泌体摄取的动态过程。十八烷基罗丹明 B 氯化物（R18）被发现可用于区分外泌体摄取过程中的内吞作用和融合作用。与细胞器标记物的共定位表明，内吞作用后外泌体被分拣到酸性囊泡中。这些结果为外泌体与细胞相互作用模式和外泌体的细胞间转运提供了新的视角。这项研究将有助于理解细胞水平上外泌体的作用。
