Adaptive MERS coronavirus-cell entry pathways and their relevance to virulence and antiviral strategies

项目总结 中东呼吸综合征冠状病毒(MERS-CoV)是人畜共患病病毒 这可能会导致潜在合并症患者的致命疾病。进一步 对这种呼吸综合征的认识和预防策略将需要一小部分 动物感染模型以及对病毒的进一步了解。这个PPG 描述了一种MERS冠状病毒病的小鼠模型。在这个模型中，引起病毒的 疾病是适应的变种，专门针对小鼠肺部感染。相比之下，非 适应的MERS冠状病毒会在小鼠身上引起感染，但不会导致疾病。这个 这个子项目(PPG2)的中心假设是，小鼠适应的变体可以 通过未适应的人无法获得的途径有效地进入宿主细胞 病毒。为了解决这一假设，将构建重组MERS-CoV并 评估以确定小鼠适应性突变在细胞进入中是否介导 病毒尖峰蛋白与有效的小鼠肺部感染相关。代理MERS-Cov 将构建和评估伪病毒，以解决以下重点假设 小鼠适应的变异体介导了早期的质膜细胞进入，即 不适用于未适应的病毒。该项目将剖析扣球产生的机制 蛋白质通过质膜调节早期细胞进入，而不是晚期细胞进入 通过内噬菌体。选择早输入和晚输入单元格的基础将是 通过识别促进或限制任一途径的宿主细胞因素来确定。这 该项目还将确定适当的抗病毒战略，通过预防早期 以及较晚的病毒细胞进入。所有这些目标的基本原理是额外的 对MERS-CoV细胞进入途径的了解将确定与Robust 感染和疾病，还将提供关于预防感染的最佳方法的见解 以及使用创新的病毒进入抑制剂治疗疾病。

PROJECT SUMMARY The Middle East Respiratory Syndrome Coronavirus (MERS-CoV) is a zoonotic virus that can cause fatal disease in patients with underlying comorbidities. Further recognition of this respiratory syndrome and prevention strategies will require a small animal infection model as well as an additional understanding of the virus. This PPG describes a mouse model of MERS-CoV disease. In this model, the viruses causing disease are adapted variants, specialized for mouse lung infection. By contrast, non- adapted MERS-CoVs cause infection in the mouse but do not cause disease. The central hypothesis of this subproject (PPG2) is that mouse-adapted variants can efficiently enter host cells through pathways that are not available to the non-adapted viruses. To address this hypothesis, recombinant MERS-CoVs will be constructed and evaluated to determine whether mouse-adaptive mutations in the cell entry-mediating viral spike proteins correlate with efficient mouse lung infection. Surrogate MERS-CoV pseudo-viruses will be constructed and evaluated to address the focused hypothesis that mouse adapted variants mediate an “early” plasma-membrane cell entry that is unavailable to non-adapted viruses. The project will dissect mechanisms by which spike proteins mediate early cell entry through plasma membranes versus late cell entry through endosomes. The basis for selection of early versus late cell entry will be determined by identifying host cell factors promoting or restricting either pathway. This project will also identify appropriate antiviral strategies that operate by preventing early and late virus-cell entry. The rationale for all of these aims is that additional understanding of MERS-CoV cell entry pathways will identify correlates of robust infection and disease, and will also provide insights on the best ways to prevent infection and disease with innovative virus entry inhibitors.