Ishikawa Tomohiro, Narita Kentaro, Matsuyama Kinichi, Masuda Michiaki
Department of Microbiology, Dokkyo Medical University School of Medicine, 880 Kita-kobayashi, Mibu 321-0293, Tochigi, Japan.
Department of Pathology, Dokkyo Medical University Hospital, 880 Kita-kobayashi, Mibu 321-0293, Tochigi, Japan.
Viruses. 2024 Mar 28;16(4):524. doi: 10.3390/v16040524.
Extracellular vesicles (EVs) such as exosomes have been shown to play physiological roles in cell-to-cell communication by delivering various proteins and nucleic acids. In addition, several studies revealed that the EVs derived from the cells that are infected with certain viruses could transfer the full-length viral genomes, resulting in EVs-mediated virus propagation. However, the possibility cannot be excluded that the prepared EVs were contaminated with infectious viral particles. In this study, the cells that harbor subgenomic replicon derived from the Japanese encephalitis virus and dengue virus without producing any replication-competent viruses were employed as the EV donor. It was demonstrated that the EVs in the culture supernatants of those cells were able to transfer the replicon genome to other cells of various types. It was also shown that the EVs were incorporated by the recipient cells primarily through macropinocytosis after interaction with CD33 and Tim-1/Tim-4 on HeLa and K562 cells, respectively. Since the methods used in this study are free from contamination with infectious viral particles, it is unequivocally indicated that the flavivirus genome can be transferred by EVs from cell to cell, suggesting that this pathway, in addition to the classical receptor-mediated infection, may play some roles in the viral propagation and pathogenesis.
细胞外囊泡（EVs），如外泌体，已被证明通过传递各种蛋白质和核酸在细胞间通讯中发挥生理作用。此外，多项研究表明，源自感染某些病毒的细胞的细胞外囊泡可以转移全长病毒基因组，导致细胞外囊泡介导的病毒传播。然而，不能排除所制备的细胞外囊泡被传染性病毒颗粒污染的可能性。在本研究中，使用携带源自日本脑炎病毒和登革热病毒的亚基因组复制子且不产生任何具有复制能力病毒的细胞作为细胞外囊泡供体。结果表明，这些细胞培养上清液中的细胞外囊泡能够将复制子基因组转移到其他各种类型的细胞中。还表明，细胞外囊泡分别与HeLa细胞和K562细胞上的CD33以及Tim-1/Tim-4相互作用后，主要通过巨胞饮作用被受体细胞摄取。由于本研究中使用的方法不存在传染性病毒颗粒污染，明确表明黄病毒基因组可通过细胞外囊泡在细胞间转移，这表明除了经典的受体介导感染外，该途径可能在病毒传播和发病机制中发挥一些作用。
