SPLUNC1 and Neutrophilic Inflammation in Cystic Fibrosis

我们K01建议的最初前提是呼吸道主机-防御蛋白短腭肺鼻腔 上皮细胞克隆-1(PLUNC，SPLunc1)调节炎症，因此可能参与急性肺损伤 肺纤维化和呼吸道感染的损伤(ALI)和组织损伤。我们定义了一种新的免疫调节作用 在增强脂多糖诱导的干扰素γ/干扰素λ相关的炎症方面，导致我们在过去几年重新关注 K01奖授予肺炎的甲型流感病毒(IAV)模型，在该模型中，干扰素反应至关重要。这导致了 提交我们的R01建议“SPLunc1--甲型流感感染期间ALI的控制机制”。 IAV的死亡很大程度上是由于肺部炎症和ALI导致的呼吸衰竭。因此，a 更好地了解IAV引起的肺部炎症和ALI的机制是一个关键的未完成的任务 需要。IAV激活内体Toll样受体(TLR3/7/8/9)诱导呼吸道和肺组织中的干扰素 免疫细胞，推动炎症，引起ALI。这一过程背后的机制并不完全 目前尚无预防ALI或加速其解决的特效药。 我们最近发现，呼吸道宿主防御蛋白PLUNC可能会增加肺部炎症和 ALI通过增强干扰素λ的表达。干扰素λ通过干扰素刺激的基因增加免疫细胞募集 增加肺部炎症和ALI。PLUNC可以作为核酸和蛋白质的支架来调节干扰素。 免疫信号蛋白，类似于其他具有TLR结合基序的宿主防御肽。PLUNC有双重功能 免疫调节特性和抗病毒作用，可减少早期上皮炎症，但可能 在临床病程后期加重肺部炎症和ALI。 在最近的工作中，我们发现Plunc-/-小鼠已经损害了干扰素λ的诱导，这种诱导保护它们免受内毒素的影响。 诱导肺部炎症和ALI。我们的初步数据现在显示Plunc-/-小鼠受到类似的保护 在IAV感染期间，PLUNC可能通过与TLR3的相互作用来调节这种效应。我们将测试 假设PLUNC通过与TLR3的相互作用调节肺部炎症，并且阻断 PLUNC控制的炎症反应减少了IAV感染过程中的ALI。我们将定义PLUNC控制的ALI 可以调节的机制，以降低IAV的发病率和死亡率。我们会做到这一点的 通过这些目标：目标1.确定PLUNC增加干扰素应答和肺的机制 IAV感染期间的炎症；目的2.确定抑制PLUNC以预防的治疗潜力 IAV-ALI和加速其恢复；以及目标3.定义PLUNC调节的免疫反应和单细胞 与ALI及其在人类中的分辨率相关的转录组图谱。理解PLUNC-TLR3的作用 ALI中的相互作用将为限制IAV发病率提供治疗靶点。这里提出的机制提供了 这是限制IAV对数百万人影响的发展机会。我们将使用这个 扩展以支持这一提议的初步数据生成，因新冠肺炎大流行而中断。

The original premise of our K01 proposal was that airway host-defense protein Short Palate Lung Nasal epithelium Clone-1 (PLUNC, SPLUNC1) regulates inflammation and therefore could contribute to acute lung injury (ALI) and tissue damage in CF and respiratory infections. We defined a novel immunomodulatory effect of SPLUNC1 in enhancing LPS-induced IFNγ/IFNλ-associated inflammation that led us to refocus the last years of the K01 award on an Influenza A virus (IAV) model of pneumonia, where IFN responses are critical. This led to the submission of our R01 proposal "SPLUNC1-controlled mechanisms of ALI during influenza A infection". IAV mortality is largely due to respiratory failure, precipitated by lung inflammation and ALI. Therefore, a better understanding of the mechanisms that drive lung inflammation and ALI caused by IAV is a critical unmet need. IAV activates endosomal Toll-Like Receptors (TLR3/7/8/9) to induce Interferons (IFN) in airway and immune cells, driving inflammation and causing ALI. The mechanisms underlying this process are not fully understood and there are no specific therapies to prevent ALI or accelerate its resolution. We recently discovered that airway host defense protein PLUNC may increase lung inflammation and ALI by enhancing IFNλ expression. IFNλ increases immune cell recruitment through IFN-stimulated genes, that increase lung inflammation and ALI. PLUNC may modulate IFN by serving as a scaffold for nucleic acids and immune signaling proteins, similar to other host defense peptides with TLR-binding motifs. PLUNC has dual immunomodulatory properties and antiviral effects that decrease early epithelial inflammation but may enhance lung inflammation and ALI later in the clinical course. In recent work we showed that Plunc-/- mice have impaired IFNλ induction that protects them from LPS- induced lung inflammation and ALI. Our preliminary data now show that Plunc-/- mice are similarly protected during IAV infection and that PLUNC may modulate this effect through interactions with TLR3. We will test the hypothesis that PLUNC regulates lung inflammation through interactions with TLR3, and that blocking PLUNC-controlled inflammation decreases ALI during IAV infection. We will define PLUNC-controlled ALI mechanisms that can be modulated to decrease the morbidity and mortality of IAV. We will accomplish this through these aims: Aim 1. Define the mechanisms by which PLUNC increases IFN responses and lung inflammation during IAV infection; Aim 2. Define the therapeutic potential of inhibiting PLUNC to protect against IAV-ALI and accelerate its recovery; and Aim 3. Define PLUNC-regulated immune response and single-cell transcriptome profiles associated with ALI and its resolution in humans. Understanding the role of PLUNC-TLR3 interactions in ALI will provide therapeutic targets to limit IAV morbidity. The mechanisms proposed here offer an opportunity for developments that would limit the impact of IAV on millions of individuals. We will use this extension to support preliminary data generation for this proposal, disrupted by the COVID-19 pandemic.