ABSTRACT: During previous routine inspections of bluegill fry (BF-2) and rainbow trout gonad (RTG-2) cells incubated with organ samples from asymptomatic Arctic char Salvelinus alpinus, brook trout Salvelinus fontinalis, and rainbow trout Oncorhynchus mykiss, a distinctive, reproducible cytopathic effect (CPE) appeared. The striking CPE, involving progressive vacuolation turning into slowly proceeding pyknotic degeneration, was originally attributed exclusively to enhanced growth of Acholeplasma sp. However, at a recent re-examination of re-infected BF-2 cells using electron microscopy (EM), conventional PCR, and quantitative PCR (qPCR), a virus was also detected. Two days post inoculation (dpi), EM revealed characteristic virions inside cytoplasmic vacuoles and next to bacteria outside the cells. The nucleotide sequences of the viral nsP3 gene fragment obtained from supernatants of infected cells were 100% identical and representative for salmonid alphavirus type 2 (SAV 2). The 16S RNA gene (16S rDNA) fragment sequences of the Mollicutes-specific PCR product obtained from SAV-infected as well as virus-free BF-2 control cells were identical with Acholeplasma laidlawii. In addition, qPCR results indicated enhanced propagation of virus and bacteria increasing with vacuolation between 5 and 8 dpi. Advanced vacuolation can be regarded as a CPE of both SAV and A. laidlawii, suggesting a viral impact on the bacterial infection that turns a latent intracellular stage into an apparent degenerative condition.

中文翻译：

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先进的空泡化表明各种沙门氏菌α2型分离株在破膜虫感染的BF-2细胞中繁殖。

摘要：在翻车鱼苗（BF-2）和彩虹的前例行检查鳟鱼性腺（RTG-2）细胞与从无症状北极炭器官样品孵育红点鲑，河鳟鱼溪红点鲑和虹鳟鱼虹鳟，一个独特的，可再现的出现细胞病变效应（CPE）。引人注目的CPE，包括逐步的空泡化，逐渐转变为缓慢的催眠性变性，最初仅归因于增强的破壁虫生长sp。但是，在最近使用电子显微镜（EM），常规PCR和定量PCR（qPCR）对重新感染的BF-2细胞进行的重新检查中，也检测到了病毒。接种后两天（dpi），EM显示细胞质液泡内和细胞外细菌旁边的特征性病毒体。从感染细胞上清液中获得的病毒nsP3基因片段的核苷酸序列100％相同，代表2型鲑鱼甲病毒（SAV 2）。的16S RNA基因（16S rDNA全）所述的片段序列柔膜从SAV感染以及无病毒的BF-2的对照细胞得到的特异性PCR产物以相同的胆甾原体laidlawii。此外，qPCR结果表明病毒和细菌的传播增强，在5到8 dpi之间空泡增加。先进的空泡化可以被认为是SAV和A.laidlawii的CPE ，表明病毒对细菌感染的影响使潜伏的细胞内阶段变成明显的退化状态。