Integrated Research Facility at Fort Detrick, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Fort Detrick, Frederick, MD 21702, USA.
College of Veterinary Medicine, Kansas State University, Manhattan, KS 66506, USA.
Viruses. 2021 Apr 7;13(4):632. doi: 10.3390/v13040632.
Simian hemorrhagic fever virus (SHFV) causes acute, lethal disease in macaques. We developed a single-plasmid cDNA-launch infectious clone of SHFV (rSHFV) and modified the clone to rescue an enhanced green fluorescent protein-expressing rSHFV-eGFP that can be used for rapid and quantitative detection of infection. SHFV has a narrow cell tropism in vitro, with only the grivet MA-104 cell line and a few other grivet cell lines being susceptible to virion entry and permissive to infection. Using rSHFV-eGFP, we demonstrate that one cricetid rodent cell line and three ape cell lines also fully support SHFV replication, whereas 55 human cell lines, 11 bat cell lines, and three rodent cells do not. Interestingly, some human and other mammalian cell lines apparently resistant to SHFV infection are permissive after transfection with the rSHFV-eGFP cDNA-launch plasmid. To further demonstrate the investigative potential of the infectious clone system, we introduced stop codons into eight viral open reading frames (ORFs). This approach suggested that at least one ORF, ORF 2b', is dispensable for SHFV in vitro replication. Our proof-of-principle experiments indicated that rSHFV-eGFP is a useful tool for illuminating the understudied molecular biology of SHFV.
猿猴出血热病毒（SHFV）可导致猕猴发生急性、致命疾病。我们构建了 SHFV 的单质粒 cDNA 启动子感染性克隆（rSHFV），并对其进行了修饰，以拯救表达增强型绿色荧光蛋白的 rSHFV-eGFP，从而可用于快速、定量检测感染。SHFV 在体外具有狭窄的细胞嗜性，仅有长尾猕猴 MA-104 细胞系和少数其他长尾猕猴细胞系容易被病毒粒子进入，且允许感染。利用 rSHFV-eGFP，我们证明了一种仓鼠科啮齿动物细胞系和三种猿猴细胞系也完全支持 SHFV 复制，而 55 个人类细胞系、11 种蝙蝠细胞系和三种啮齿动物细胞系则不支持。有趣的是，一些对 SHFV 感染明显有抗性的人类和其他哺乳动物细胞系在用 rSHFV-eGFP cDNA 启动子质粒转染后是允许感染的。为了进一步证明感染性克隆系统的研究潜力，我们在八个病毒开放阅读框（ORF）中引入了终止密码子。这种方法表明，至少一个 ORF（ORF2b'）对于 SHFV 在体外复制是可有可无的。我们的初步实验表明，rSHFV-eGFP 是阐明 SHFV 分子生物学的有用工具。
