Fedewa Greg, Radoshitzky Sheli R, Chī Xiǎolì, Dǒng Lián, Zeng Xiankun, Spear Melissa, Strauli Nicolas, Ng Melinda, Chandran Kartik, Stenglein Mark D, Hernandez Ryan D, Jahrling Peter B, Kuhn Jens H, DeRisi Joseph L
Integrative Program in Quantitative Biology, Bioinformatics, University of California San Francisco, San Francisco, CA, USA.
United States Army Medical Research Institute of Infectious Diseases, Fort Detrick, Frederick, MD, USA.
Virus Evol. 2018 Nov 28;4(2):vey034. doi: 10.1093/ve/vey034. eCollection 2018 Jul.
Ebola virus (EBOV) disease is a viral hemorrhagic fever with a high case-fatality rate in humans. This disease is caused by four members of the filoviral genus , including EBOV. The natural hosts reservoirs of ebolaviruses remain to be identified. Glycoprotein 2 of reptarenaviruses, known to infect only boa constrictors and pythons, is similar in sequence and structure to ebolaviral glycoprotein 2, suggesting that EBOV may be able to infect reptilian cells. Therefore, we serially passaged EBOV and a distantly related filovirus, Marburg virus (MARV), in boa constrictor JK cells and characterized viral infection/replication and mutational frequency by confocal imaging and sequencing. We observed that EBOV efficiently infected and replicated in JK cells, but MARV did not. In contrast to most cell lines, EBOV-infected JK cells did not result in an obvious cytopathic effect. Surprisingly, genomic characterization of serial-passaged EBOV in JK cells revealed that genomic adaptation was not required for infection. Deep sequencing coverage (>10,000×) demonstrated the existence of only a single nonsynonymous variant (EBOV glycoprotein precursor pre-GP T544I) of unknown significance within the viral population that exhibited a shift in frequency of at least 10 per cent over six serial passages. In summary, we present the first reptilian cell line that replicates a filovirus at high titers, and for the first time demonstrate a filovirus genus-specific restriction to MARV in a cell line. Our data suggest the possibility that there may be differences between the natural host spectra of ebolaviruses and marburgviruses.
埃博拉病毒（EBOV）病是一种在人类中具有高病死率的病毒性出血热。该疾病由丝状病毒属的四个成员引起，包括埃博拉病毒。埃博拉病毒的自然宿主贮主仍有待确定。已知仅感染蟒蛇和蚺蛇的沙粒病毒糖蛋白2在序列和结构上与埃博拉病毒糖蛋白2相似，这表明埃博拉病毒可能能够感染爬行动物细胞。因此，我们在蟒蛇JK细胞中对埃博拉病毒和一种远亲丝状病毒——马尔堡病毒（MARV）进行了连续传代，并通过共聚焦成像和测序对病毒感染/复制及突变频率进行了表征。我们观察到埃博拉病毒在JK细胞中能有效感染和复制，但马尔堡病毒不能。与大多数细胞系不同，感染埃博拉病毒的JK细胞未产生明显的细胞病变效应。令人惊讶的是，对JK细胞中连续传代的埃博拉病毒进行基因组表征发现，感染并不需要基因组适应。深度测序覆盖度（>10000×）表明，在病毒群体中仅存在一个意义不明的非同义变异（埃博拉病毒糖蛋白前体pre-GP T544I），该变异在六次连续传代中频率至少有10%的变化。总之，我们首次展示了一种能以高滴度复制丝状病毒的爬行动物细胞系，并首次在细胞系中证明了丝状病毒属对马尔堡病毒的特异性限制。我们的数据表明，埃博拉病毒和马尔堡病毒的自然宿主谱可能存在差异。
