Department of Aquatic Animal Medicine, College of Fisheries, Huazhong Agricultural University, Wuhan 430070, China.
Laboratory for Marine Biology and Biotechnology, Pilot National Laboratory for Marine Science and Technology (Qingdao), Qingdao 266237, China.
Viruses. 2021 May 10;13(5):870. doi: 10.3390/v13050870.
Grass carp reovirus (GCRV) causes serious losses to the grass carp industry. At present, infectious tissues of GCRV have been studied, but target cells remain unclear. In this study, peripheral blood cells were isolated, cultured, and infected with GCRV. Using quantitative real-time polymerase chain reaction (qRT-PCR), Western Blot, indirect immunofluorescence, flow cytometry, and transmission electron microscopy observation, a model of GCRV infected blood cells in vitro was established. The experimental results showed GCRV could be detectable in leukocytes only, while erythrocytes and thrombocytes could not. The virus particles in leukocytes are wrapped by empty membrane vesicles that resemble phagocytic vesicles. The empty membrane vesicles of leukocytes are different from virus inclusion bodies in kidney (CIK) cells. Meanwhile, the expression levels of , , , were significantly up-regulated in leukocytes, indicating that GCRV could cause the production of the related immune responses. Therefore, GCRV can infect leukocytes in vitro, but not infect erythrocytes and thrombocytes. Leukocytes are target cells in blood cells of GCRV infections. This study lays a theoretical foundation for the study of the GCRV infection mechanism and anti-GCRV immunity.
草鱼呼肠孤病毒（GCRV）会给草鱼养殖业造成严重损失。目前，已对 GCRV 的感染组织进行了研究，但靶细胞仍不清楚。本研究分离培养了草鱼外周血白细胞，并感染 GCRV。通过实时荧光定量聚合酶链式反应（qRT-PCR）、Western Blot、间接免疫荧光、流式细胞术和透射电镜观察，建立了 GCRV 体外感染血细胞的模型。实验结果表明，白细胞中可检测到 GCRV，而红细胞和血小板中则不能。白细胞中的病毒颗粒被类似吞噬小体的空膜泡包裹。白细胞的空膜泡与来源于肾脏（CIK）细胞的病毒包涵体不同。同时，白细胞中 、 、 、 的表达水平显著上调，表明 GCRV 能引起相关免疫反应的产生。因此，GCRV 可以在体外感染白细胞，但不能感染红细胞和血小板。白细胞是 GCRV 感染血细胞的靶细胞。本研究为 GCRV 感染机制和抗 GCRV 免疫的研究奠定了理论基础。
