Reactive Oxygen Species in Anti-Viral Airway Host Defense

描述(申请人提供)：甲型流感是一种典型的新兴疾病。基因重组和/或对新宿主的适应可导致高死亡率的灾难性大流行。流感病毒在呼吸道上皮细胞中感染和复制，并诱导由中性粒细胞和单核细胞组成的炎性浸润物。最初的先天免疫反应是在呼吸道上皮的顶端表面启动的，位于最近发现的NADPH氧化酶DUOX所在的位置。DUOX产生活性氧物种，并与伤口愈合以及pH和氧化还原环境的变化有关。这些特点使DUOX成为空气微生物致病过程中局部免疫反应的理想参与者。这个项目使用正向遗传学来阐明DUOX蛋白是如何调节细胞内信号通路的，这是抗病毒宿主防御所必需的。DUOX和吞噬细胞氧化酶NOX2也是调节白细胞进入肺部的主要候选者。体外分化的人肺上皮细胞和分离的人中性粒细胞将被结合在一个模型系统中，该模型系统允许通过免疫荧光和电子显微镜进行遗传操作和结构变化的可视化。我们的研究将表明，氧化酶是否是治疗药物开发的有前途的靶点。

Description (provided by applicant): Influenza A is a classic emerging disease. Genetic reassortment and/or adaptation to a new host can cause disastrous pandemics with high mortality. Influenza virus infects and replicates in the respiratory epithelium and induces inflammatory infiltrates comprised of neutrophils and monocytes. The primary innate immune response is initiated at the apical surface of the airway epithelium, at a location where a recently identified NADPH oxidase, Duox, resides. Duox generates reactive oxygen species, and has been implicated in wound healing and in changes of the pH and redox environment. These features position Duox as an ideal participant in the local immune response during airborne microbial pathogenesis. This project uses forward genetics to elucidate how Duox proteins regulate intracellular signaling pathways essential for anti-viral host defense. Duox and the phagocyte oxidase Nox2 are also prime candidates for regulating leukocyte trafficking into the lungs. An in vitro differentiated human lung epithelium and isolated human neutrophils will be combined in a model system that permits genetic manipulation and visualization of structural changes by immunofluorescence and electron microscopy. Our studies will show if oxidases are a promising target for therapeutic drug development.