Evaluation of Host miRNAs as Therapeutics against Encephalitogenic Flaviviruses

描述(申请人提供)：嗜神经性黄病毒，包括西尼罗河病毒(WNV)和日本脑炎病毒(JEV)，是蚊媒病毒，在全球范围内引起显著的发病率和死亡率。不幸的是，目前治疗与这些病毒相关的疾病的选择有限。我们等人最近的研究表明，microRNAs(MiRNAs)通过调节病毒和宿主基因的表达，在多种病毒的生命周期中发挥重要作用。因此，miRNAs代表了治疗干预的潜在靶点，无论是通过增强或拮抗它们在病毒感染细胞中的功能。在这项应用中，我们建议筛选miRNA类似物和反义抑制剂的文库，以确定代表潜在治疗靶点的单个miRNA 干预。由于miRNAs的功能预计是通过靶向细胞mRNAs和宿主细胞途径的基因表达来实现的，因此我们将使用RNA诱导沉默复合体(RISC)的免疫沉淀、生物信息学分析和实验验证来确定这些靶点和途径。因此，在完成该提案的R21部分后，我们预计已经确定了多个miRNAs，它们的活性可以被调节以抑制WNV和JEV的复制，并表征了它们的作用机制。在该提案的R33部分，将在WNV和JEV感染的小鼠模型中评估已识别的miRNAs的治疗潜力。 公共卫生相关性：西尼罗河病毒和日本脑炎是全世界病毒性脑炎的主要原因。由于这些病毒需要多种宿主细胞蛋白和途径来完成它们的复制周期，我们建议开发细胞microRNAs，它本身调节宿主细胞蛋白和途径的表达，作为对抗这些病毒的潜在疗法。

DESCRIPTION (provided by applicant): The neurotropic flaviviruses, including West Nile virus (WNV) and Japanese Encephalitis virus (JEV) are mosquito borne viruses that cause significant morbidity and mortality worldwide. Unfortunately, current therapeutic options for treating disease associated with these viruses are limited. Recent studies by our group and others have demonstrated that microRNAs (miRNAs) play a major role in the life cycle of multiple viruses via regulation of both viral and host gene expression. miRNAs, therefore, represent potential targets for therapeutic intervention, either through enhancing or antagonizing their functions in virally infected cells. In this application, we propose to screen a library of miRNA analogs and antisense inhibitors to identify individual miRNAs that represent potential targets for therapeutic intervention. Because miRNAs are expected to function by targeting gene expression of cellular mRNAs and host-cell pathways, we will identify these targets and pathways using immunoprecipitation of the RNA-induced silencing complex (RISC), bioinformatic analysis, and experimental verification. Therefore, at the completion of the R21 portion of this proposal, we expect to have identified multiple miRNAs whose activity can be modulated to inhibit WNV and JEV replication, as well as to have characterized their mechanism of action. In the R33 portion of the proposal, fully characterized miRNAs will be evaluated for therapeutic potential of identified miRNAs in a mouse model of WNV and JEV infection. PUBLIC HEALTH RELEVANCE: West Nile virus and Japanese encephalitis are major causes of viral encephalitis throughout the world. Because these viruses require multiple host-cell proteins and pathways to complete their replication cycle, we propose to develop cellular microRNAs, which themselves regulate expression of host-cell proteins and pathways, as potential therapeutics to combat these viruses.