Dual oxidase and lactoperoxidase in influenza infection

项目概要描述 流感病毒感染每年影响全世界数百万人并导致严重死亡。 目前的治疗选择仅限于病毒株特异性疫苗接种，并且由于抗病毒药物而存在问题 阻力。迫切需要确定新的宿主先天免疫机制，提供广泛的 预防流感。支气管上皮细胞协调氧化细胞外抗菌系统 存在于气道表面液体中，由蛋白质乳过氧化物酶 (LPO)、硫氰酸根阴离子 (SCN- ）和过氧化氢（H2O2）。 LPO 使用 H2O2 将 SCN- 氧化成次硫氰酸盐 (OSCN-)，已知 体外抗病毒作用。双氧化酶 1 (Duox1) 是一种在支气管上皮细胞中高表达的 NADPH 氧化酶， 是系统的 H2O2 源。我们的长期目标是确定 Duox1/H2O2/LPO/SCN- 抗病毒系统可以在流感感染中被操纵，以达到对人类患者的治疗目的。的 该提案的目的是确定和表征 Duox1 和 LPO 对流感的抗病毒作用 在多个实验系统中。我们的初步数据表明1）原代支气管上皮细胞失活 多种流感病毒以 Duox1/H2O2/LPO/SCN 依赖性方式存在，2) Duox1 缺陷小鼠 流感后死亡率和发病率增加，病毒清除和白细胞招募受损 体内感染，3）可增强该机制的体外流感灭活作用，以抑制 流感感染。基于这些数据，我们的中心假设是 Duox1/H2O2/LPO/SCN- 系统 在体外和体内均能减弱流感感染，并可增强抗流感能力。理由 拟议的研究是需要更好地了解基于 Duox1/LPO 的抗病毒药物有多强大 系统是什么以及如何操纵它来达到治疗目的。主要假设将在细胞中进行检验 使用多种流感毒株的免费气道上皮和小鼠模型系统。预计 我们的目标将产生几个有影响力的成果，包括 1) 抗流感机制的详细描述 Duox1/H2O2/LPO/SCN-系统的作用； 2) 确定 Duox1 在对抗 a 中的体内相关性 广泛的流感毒株； 3) 探索 Duox1/H2O2/LPO/SCN-系统的治疗潜力 提高流感清除率并减少相关的肺损伤。我们的创新工作表明 Duox1/H2O2/LPO/SCN-系统可灭活流感，并使用 Duox1 缺陷型小鼠品系进行体内研究。 上述工作的意义在于建立一种新型先天免疫机制的相关性 可以增强呼吸道以减轻流感感染或与流感联合应用 疫苗可能会增强功效。总之，我们提出的工作将在这些领域产生积极影响 通过鉴定 Duox1 和 LPO 来研究气道上皮生物学和抗病毒先天免疫反应， 支气管上皮细胞对抗流感的重要武器。

Project summary description Influenza virus infections affect millions of people worldwide every year and cause serious mortality. Current treatment options are limited to viral strain-specific vaccination and are problematic due to antiviral drug resistance. There is an urgent need to identify novel host innate immune mechanisms providing broad range protection against influenza. Bronchial epithelial cells orchestrate an oxidative extracellular antimicrobial system present in the airway surface liquid consisting of the protein lactoperoxidase (LPO), the thiocyanate anion (SCN- ) and hydrogen peroxide (H2O2). LPO oxidizes SCN- using H2O2 into hypothiocyanite (OSCN-) that has known in vitro antiviral effects. Dual oxidase 1 (Duox1), an NADPH oxidase highly expressed in bronchial epithelial cells, is the H2O2 source for the system. Our long-term goal is to determine whether the Duox1/H2O2/LPO/SCN- antiviral system could be manipulated in influenza infection for therapeutic purposes in human patients. The objective of this proposal is to determine and characterize the antiviral role of Duox1 and LPO against influenza in multiple experimental systems. Our preliminary data show that 1) primary bronchial epithelial cells inactivate several influenza viruses in an Duox1/H2O2/LPO/SCN- -dependent manner, 2) Duox1-deficient mice have increased mortality and morbidity, impaired viral clearance and leukocyte recruitment following influenza infection in vivo, and 3) the in vitro influenza-inactivating effect of this mechanism can be enhanced to inhibit influenza infection. Based on these data, our central hypothesis is that the Duox1/H2O2/LPO/SCN- system attenuates influenza infection, both in vitro and in vivo, and can be boosted to fight influenza. The rationale for the proposed research is that there is a need to better understand how powerful the antiviral Duox1/LPO-based system is and how can it be manipulated for therapeutic purposes. The main hypothesis will be tested in cell- free, airway epithelial and mouse model systems using a wide range of influenza strains. It is anticipated that our aims will yield several impactful outcomes including 1) detailed description of the anti-influenza mechanism of action of the Duox1/H2O2/LPO/SCN- system; 2) determination of the in vivo relevance of Duox1 in fighting a wide range of influenza strains; and 3) exploring the therapeutic potential of the Duox1/H2O2/LPO/SCN- system to improve influenza clearance and to diminish associated lung damage. Our innovative work shows that the Duox1/H2O2/LPO/SCN- system inactivates influenza, and uses a Duox1-deficient mouse strain for in vivo studies. The significance of the outlined work relies in establishing the relevance of a novel innate immune mechanism of the airways that can be enhanced to attenuate influenza infections or applied in conjunction with influenza vaccines to potentially enhance efficacy. In summary, our proposed work will have a positive impact in the fields of airway epithelial biology and antiviral innate immune responses by identifying Duox1 and LPO, as novel, crucial weapons of the bronchial epithelium against influenza.