Early Responses to Influenza A Virus Replication In Vivo

项目摘要 甲型流感病毒是一种季节性病原体，有可能导致不可预测的毁灭性大流行。 流感在呼吸道内具有广泛的趋向性，可感染许多不同的上皮细胞亚群。 这些上皮细胞是流感感染的主要目标，负责放大和 传播感染。这些细胞也是检测病毒和启动抗病毒免疫的关键哨兵。 回应。很难确定早期复制事件，因为很难快速标记受感染的细胞 在感染之后。此外，病毒在肺内传播，使低复制很难解开。 来自新的感染的水平。为了克服这些警告，我们使用了一个强大的单周期报告系统 标记受感染的细胞，并限制为感染的第一种细胞类型。我们的初步数据表明，细胞 支持不同水平的病毒复制，表达不同的干扰素刺激基因集。这些数据 证明抗病毒反应已调整到复制水平。使用顺序感染策略 其中单循环病毒表达离散的荧光团以专门标记初级和次级 被感染的细胞我们已经证明纤毛上皮细胞在第二个 病毒复制的浪潮。这些数据表明，病毒的趋向性在很大程度上是由先天免疫决定的。 病毒传播过程中的响应。这项研究的目的是确定抑制 流感病毒复制和确定病毒趋向性在先天免疫反应中如何改变 活着。我们的中心假设是，细胞对感染的反应会根据病毒的不同阶段进行调整 复制和一轮感染，影响整体病毒复制水平和细胞趋向性。我们的 研究将通过使用一组报告病毒来解决这一假设，这些病毒可以确定 复制的程度、阶段和轮次，以阐明体内基本的抗病毒过程。我们将解决 这一假设有两个目的。目标1将确定不同水平的复制如何导致独特的ISG 以及由此产生的效应蛋白在抗病毒反应中的作用。目标2将集中于阐明 病毒传播过程中上皮细胞亚群的保护机制。这项提案的结果将揭开 病毒-宿主相互作用和抗病毒免疫的基本机制。

Project Summary Influenza A virus is a seasonal pathogen with the potential to unpredictably cause devastating pandemics. Influenza has a broad tropism within the respiratory tract infecting many different subsets of epithelial cells. These epithelial cells are the primary target of influenza infection and are responsible for amplifying and spreading the infection. These cells are also critical sentinels detecting the virus and initiating antiviral immune responses. It is difficult to determine early replication events because it is hard to label infected cells rapidly after infection. Additionally, the virus spreads within the lung making it difficult to disentangle low replication levels from new infections. To overcome these caveats, we used a single cycle reporter system that robustly labels infected cells and is restricted to the first cell types infected. Our preliminary data demonstrate that cells supporting different levels of virus replication express distinct sets of interferon-stimulated genes. These data demonstrate that the antiviral response is tuned to level of replication. Using a sequential infection strategy where the single cycle viruses express discrete fluorophores to specifically label primary and secondary infected cells we have demonstrated that ciliated epithelial cells are specifically protected during the second wave of virus replication. These data demonstrate that virus tropism is significantly shaped by innate immune responses during virus dissemination. The objective of this research is to determine responses that inhibit influenza virus replication and to determine how virus tropism is altered during innate immune responses in vivo. Our central hypothesis is that cellular responses to infection become tailored to the stages of viral replication and the round of infection which impacts overall viral replication levels and cellular tropism. Our studies will address this hypothesis through use of a combination of reporter viruses that can determine the degree, stage, and round of replication to elucidate fundamental antiviral processes in vivo. We will address this hypothesis in two aims. Aim 1 will be to determine how varying levels of replication induce unique ISGs and the role of the resulting effector proteins in the antiviral response. Aim 2 will focus on elucidating the mechanisms of protection of epithelial cell subsets during virus spread. Results from this proposal will uncover fundamental mechanisms in virus-host interactions and antiviral immunity.