Studies in Poxvirus Host Range Genes and Tropism

项目摘要 我们建议研究调节One的物种专一性和趋向性的分子途径。 特殊的痘病毒，即粘液瘤病毒(MV)。MV是一种兔子特有的痘病毒，它能引起截然不同的 疾病概况取决于特定的兔子物种，但对所有其他宿主物种都是非致病的， 包括人类。我们的实验室对MV及其在兔身上引起的疾病进行了广泛的研究，称为粘液瘤病， 作为研究痘病毒发病的基本原理的模型系统，特别是通过利用 我们的大量且不断增长的靶向MV基因敲除构建。几年前，我们 出人意料地发现，通常不允许感染MV的小鼠原代细胞可以 通过阻断细胞干扰素(干扰素)的反应，使其完全允许。这项工作随后导致了 发现大多数被测试的人类癌细胞对MV完全允许，而且MV是 溶瘤疗法在多种动物体内治疗人癌移植瘤的显著效果 模特们。我们还发现，两个病毒宿主范围因子(M-T5和M063)也对允许 MV在许多人类癌细胞中复制，我们可以操纵病毒的传递和溶瘤作用 通过这些病毒蛋白和它们的宿主细胞蛋白靶标。最后，我们最新的观察涉及到 这一建议是干扰素和肿瘤协同保护原代人类细胞免受MV感染。 肿瘤坏死因子(TNF)。我们建议： 1-评估病毒宿主范围因素在人类癌细胞MV趋向性中的作用。我们建议 通过分析MV寄主范围蛋白与寄主细胞信号分子(如Akt)的相互作用 突变、siRNA敲除、信号抑制物和蛋白质微阵列。我们将测试一些 辅助策略，如用于人类癌症化疗的信号调节剂药物，以增加MV 对更广泛的人类癌细胞的溶瘤潜力。 2-探讨宿主干扰素和肿瘤坏死因子在MV趋向性中的作用。我们将学习MV淘汰赛 几种关键病毒宿主基因缺失的病毒研究它们在抑制干扰素中的作用 或肿瘤坏死因子反应，调节MV的趋向性和溶瘤作用。这一新信息将允许更多 针对更广泛的人类癌症优化MV病毒治疗的合理方法，以及 控制原代非癌症人类细胞中的MV复制。

Project Summary We propose to examine the molecular pathways that mediate the species specificity and tropism of one particular poxvirus, namely myxoma virus (MV). MV is a rabbit-specific poxvirus that induces distinctly different disease profiles depending on the specific rabbit species but is nonpathogenic for every other host species, including man. Our lab has extensively studied MV and the disease it causes in rabbits, called myxomatosis, as a model system to investigate the fundamental principles of poxvirus pathogenesis, particularly by exploiting our large and growing collection of targeted MV gene knockout constructs. Several years ago, we unexpectedly discovered that primary mouse cells, which are normally nonpermissive for MV infection, could be rendered fully permissive by interrupting the cellular interferon (IFN) responses. This work then led to the discovery that the majority of human cancer cells tested were fully permissive for MV and that MV is remarkably effective as oncolytic therapy for the treatment of human cancer xenografts in a variety of animal models. We also discovered that two viral host range factors (M-T5 and M063) were also critical for permissive MV replication in many human cancer cells and we could manipulate viral permissiveness and oncolysis through these viral proteins and their host cell protein targets. Finally, our most recent observation related to this proposal is that primary human cells are protected from MV infection synergistically by IFN and tumor necrosis factor (TNF). We propose to: 1- Evaluate the roles of viral host range factors in MV tropism for human cancer cells. We propose to analyze the interactions of MV host range proteins with host cell signaling molecules (like Akt) by mutagenesis, siRNA knockdowns, signaling inhibitors and protein microarrays. We will test a number of adjunct strategies, like signaling modifier drugs used for cancer chemotherapy in man, to increase MV oncolytic potential for a wider spectrum of human cancer cells. 2- Investigate the role of host IFN and TNF responses in MV tropism. We will study MV knockout viruses that are deleted in several key viral host range genes to investigate their roles in inhibiting IFN or TNF responses, and modulating MV tropism and oncolysis. This new information will allow for more rational approaches to optimizing MV virotherapy against a wider spectrum of human cancers, and for controlling MV replication in primary noncancerous human cells.