Chemical intervention of influenza virus RNA nuclear export

 描述(申请人提供)：流感病毒每年导致美国约36,000人死亡，全球每年约500,000人死亡。极具致病性的菌株导致了全球大量死亡，例如1918年的大流行导致世界各地约3000万人死亡。目前，只有两种方法可用于预防或治疗流行性和大流行性流感，即接种疫苗和抑制病毒复制。疫苗接种虽然对同源毒株非常有效，但在老年人中失去效力，而且受到病毒高度突变的性质的限制，迫使疫苗每年重新配制，以匹配当前流感病毒流通毒株的抗原性。一些药物已被批准用于治疗流感。这些药物可以抑制病毒脱壳或病毒传播，但这些数量相对较少的抗病毒药物的使用受到耐药病毒株的出现的限制。因此，显然需要为流感病毒疾病的治疗提供更多的治疗方式。在这项申请中，我们涉及到一个新的发现平台的开发，用于鉴定抑制流感病毒RNA核输出的化合物。流感病毒RNA被输入宿主细胞核进行复制，然后以mRNAs或vRNAs的形式从细胞核输出，分别表达病毒蛋白或产生新的病毒颗粒。因此，阻断细胞核中的vRNAs或病毒mRNAs会导致病毒复制的抑制。我们有证据表明，我们可以在完整的感染细胞中跟踪单个病毒vRNA和mRNA片段，并且这一过程是可以调控的。我们将利用我们的~200,000个化合物文库和我们的高通量成像平台，使用这一方法来检测对病毒RNA核输出的抑制。该屏幕建议用于应用程序的R21阶段。对于R33阶段，将对选定的HITS进行结构活性关系的改进 不同毒株流感病毒在细胞和动物模型中的效力、选择性、稳定性和毒性分布。总之，这个发现平台确定的化合物很可能代表了一类新的潜在抗病毒药物，可能有助于对抗流感病毒，以及可能使用类似核出口机制的其他病毒。

 DESCRIPTION (provided by applicant): Influenza viruses cause approximately 36,000 deaths annually in the United States and ~500,000 deaths worldwide per year. Strains that are extremely pathogenic have been responsible for high numbers of deaths worldwide, such as the 1918 pandemic which led to ~30 million deaths around the world. Currently, there are only two approaches available for preventing or treating epidemic and pandemic influenza, vaccination and inhibitors of viral replication. Vaccination, although highly effective against homologous strains, looses efficacy in the elderly, and it is limited by the highly mutable nature of the viru, forcing the annual reformulation of the vaccine to match the antigenicity of the current influenza virus circulating strains. A number of drugs have been approved for the treatment of influenza. These drugs inhibit virus uncoating or virus spread but the use of these relatively small number of antiviral drugs is limited by the appearance of resistant virus strains. Thus, there is a clear need for additional therapeutic modalities for the treatment of influenza virus disease. In this application, we deal with the development of a new discovery platform for the identification of chemical compounds that inhibit influenza virus RNA nuclear export. Influenza virus RNAs are imported into the host cell nucleus for replication and are then exported from the nucleus as mRNAs or vRNAs to express viral proteins or generate new viral particles, respectively. Therefore, blockage of vRNAs or viral mRNAs in the nucleus results in inhibition of virus replication. We have evidence demonstrating that we can follow single viral vRNA and mRNA segments in intact infected cell and that this process can be regulated. We will use this assay to detect inhibition of viral RNA nuclear export using our ~200,000 compound library and our high throughput imaging platform. The screen is proposed for the R21 phase of the application. For the R33 phase, the selected hits will be subjected to structure activity relationship for improving potency, selectivity, stability and toxicity profile in cell based and animal based models with various strains of influenza virus. In sum, the identified compounds by this discovery platform will likely represent a new class of potential antivirals that could be useful for antagonizing influenza virus and possibly other viruses that use a similar nuclear export machinery.