中华鳖病毒（TSV）对鱼类细胞的感染试验

Susceptibility of Fish Cell Lines to Trionyx Sinesis Virus

将１２种鱼类增养细胞用于中华鳖病毒（Ｔrionyx sinesis virus,ＴＳＶ）的体外感染试 验。结果显示，ＴＳＶ能使鲤鱼上皮乳状瘤细胞（ＥＰＣ）、鳗鲡性腺细胞（ＥＧ）和草鱼卵巢细胞（ＣＯ）产生病变。比较了不同培养温度对ＴＳＶ感染鱼类细胞的影响以及ＴＳＶ引起鱼类细胞病变的特征。ＴＳＶ引起３种鱼类细胞病变，经显微观察，它们具有不同的病变特征。ＴＳＶ感染细胞后，其ＴＣＩＤ５０在２０～３０℃范围内。

In order to look for sensitive cell lines convenient to growth of the Trionyx sinesis virus, TSV, which isolated from the diseased turtles with lethal symptoms, monolayer cultures of 12 established fish cell lines were experimentally infected with the TSV isolates. Three fish cell lines, EPC (epithelioma papulosum cyprini), CO(Ctenopharyngodon idellus ovaries) and EG(eel gonad), were found to be susceptible to the TSV. There existed obvious difference of cytopathogenic appearence among the three cell lines at the same conditions. The cytopathogenic effect of EPC cells first appeared in the form of focal areas of rounded cells. Many small cavities were observed at first under light microscopy, then the cavities enlarged and lysis ensued. The replicated TSV particles were observed by electron microscopy in the infected EPC cell nuclei and cytoplasms. A large number of virus particles were found to be associated with the fibre like structures in cytoplasm of the infected cells. The virus particles isolated from the infected EPC cells were confirmed to be consistent with the TSV isolated from tissues of the diseased turtles in their size and shape, with approximate 30 nm in diameter. Monolayers of EPC cell cultures were infected with 10 fold dilutions of the TSV isolates and incubated at 20℃, 25℃and 30℃. The proliferation rate of TSV in EPC cells was found to be promoted as the incubation temperature increase from 20℃ to 30℃. The TCID 50 was 10 4.5 , 10 6 and 10 7 respectively under the temperature of 20℃, 25℃ and 30℃.