Neutrophil Extracellular Traps and Host Immunity

项目摘要 除了吞噬作用和细胞内氧化杀死病原体的经典模式外，最近， 发现中性粒细胞的抗微生物功能是形成细胞外陷阱（NeutrophilicExtracellular 诱捕器（Traps），NET），其可以在细胞外诱捕并杀死病原体。由于NET形成（NETosis）通常需要 活性氧（ROS）的产生，我们和其他人已经发现，从慢性中性粒细胞 具有NADPH氧化酶复合物突变的肉芽肿病（CGD）患者和Gp 91 phox-/- CGD小鼠 在体外和体内对各种刺激和肺部细菌的反应中表现出受损的NET生成， 感染我们最近报道了他莫昔芬（TMX），FDA批准的选择性雌激素受体（ER） 用于治疗乳腺癌的修饰剂，以ROS非依赖性方式诱导CGD中性粒细胞中的抗微生物NET 方式我们进一步表明，自噬的激活是必要的，足以诱导TMX介导的凋亡。 NET。除了这份开创性的报告外，拟议研究的前提来自我们的初步研究。 数据表明TMX通过非经典自噬作用引起ROS和ER非依赖性NETosis的新途径 activation.提出的两个具体目标将建立TMX作为NET诱导剂，具有抗菌和抗 在临床前鼠CGD和人CGD中性粒细胞中炎症作用（目的1）;并阐明TMX介导的 中性粒细胞中的非经典自噬信号通路，其最终导致核纤层解体， 协助释放母语英语教师（目标2）。我们的研究为一种新的自噬机制提供了重要的机制见解 TMX激活的途径，这将不仅对NET研究，而且对开发 自噬和NET来治疗感染性和自身免疫性疾病。利用井里的中性粒细胞- 这些研究也提供了一个令人兴奋的机会， 用于CGD中TMX的临床前试验，以恢复中性粒细胞的抗微生物功能， 细菌感染，在这些患者中经常观察到。

Project Summary In addition to the classical mode of phagocytosis and intracellular oxidative killing of pathogens, a recently discovered antimicrobial function of neutrophils is the formation of extracellular traps (Neutrophil Extracellular Traps, NETs), which can trap and kill pathogens extracellularly. As NET formation (NETosis) generally requires reactive oxygen species (ROS) generation, we and others have found that neutrophils from Chronic Granulomatous Diseases (CGD) patients and Gp91phox-/- CGD mice with mutations in NADPH oxidase complex exhibit impaired NET generation in-vitro and in-vivo in response to various stimuli and pulmonary bacterial infection. We recently reported that Tamoxifen (TMX), an FDA approved selective estrogen receptor (ER) modifier for treatment of breast cancer, induces antimicrobial NETs in CGD neutrophils in a ROS independent manner. We further showed that activation of autophagy is necessary and sufficient to induce TMX-mediated NETs. In addition to this seminal report, the premise of the proposed research is derived from our preliminary data indicating a novel pathway of ROS-and ER-independent NETosis by TMX via a non-canonical autophagy activation. The two proposed specific aims will establish TMX as NET-inducing agent with antimicrobial and anti- inflammatory effect in preclinical murine CGD and human CGD neutrophils (Aim 1); and elucidate TMX-mediated non-canonical autophagy signaling pathway in neutrophils that culminates in disintegration of nuclear lamina to facilitate the release of NETs (Aim 2). Our studies provide important mechanistic insights into a novel autophagy pathway activated by TMX which will have implications not only for NET research but also for exploiting autophagy and NETs to treat infectious and autoimmune diseases. By leveraging neutrophils from a well- characterized cohort of CGD patients at NIH Clinical Center, these studies also present an exciting opportunity for preclinical testing of TMX in CGD to restore antimicrobial function of neutrophils to combat pneumonic bacterial infections, frequently observed in these patients.