Van Dong Hieu, Tran Giang Thi Huong, Trinh Dai Quang, Takeda Yohei, Ogawa Haruko, Imai Kunitoshi
United Graduate School of Veterinary Sciences, Gifu University, 1-1 Yanagido, Gifu City 501-1193, Japan.
Department of Veterinary Medicine, Obihiro University of Agriculture and Veterinary Medicine, 2-11 Inada, Obihiro, Hokkaido 080-8555, Japan.
Pathogens. 2020 Oct 15;9(10):842. doi: 10.3390/pathogens9100842.
Persistent infection of chicken anemia virus (CAV) in chickens has been suspected to result in immunosuppression and exogenous virus contamination within vaccine production. However, no direct evidence for persistent CAV infection has thus far been obtained. In this study, we aimed to establish an in vitro model of persistent CAV infection. CAV-infected MDCC-MSB1 (MSB1) cells, a Marek's disease virus-transformed continuous cell line, were cultured in the presence of both CAV and CAV neutralizing antibody (NA). Cell viability, expression of viral antigens, viral DNA, and recovery of CAV were examined by acridine orange/propidium iodide staining, immunofluorescence measurement, real-time PCR, and viral isolation, respectively. The results indicated that CAV was maintained and possibly replicated in CAV-infected cells cultured in the presence of NA, without affecting host cell viability. It was also shown that persistently infectious CAV induced cell death again after removing NA. The persistent infection of CAV in MSB1 cells was not related to viral gene mutation. In summary, we have herein established a novel model of persistent CAV infection in MSB1 cells cultured in the presence of NA.
鸡贫血病毒（CAV）在鸡体内的持续感染被怀疑会导致免疫抑制以及疫苗生产过程中的外源病毒污染。然而，迄今为止尚未获得CAV持续感染的直接证据。在本研究中，我们旨在建立一个CAV持续感染的体外模型。将感染CAV的MDCC-MSB1（MSB1）细胞（一种马立克氏病病毒转化的连续细胞系）在CAV和CAV中和抗体（NA）存在的情况下进行培养。分别通过吖啶橙/碘化丙啶染色、免疫荧光测定、实时PCR和病毒分离来检测细胞活力、病毒抗原表达、病毒DNA以及CAV的回收情况。结果表明，在NA存在的情况下培养的CAV感染细胞中，CAV得以维持并可能进行复制，且不影响宿主细胞活力。还表明，去除NA后，持续感染性的CAV会再次诱导细胞死亡。CAV在MSB1细胞中的持续感染与病毒基因突变无关。总之，我们在此建立了一种在NA存在的情况下培养的MSB1细胞中CAV持续感染的新模型。
