Lung epithelial cell-derived C3 in acute lung injury

肺上皮细胞衍生的 C3 在急性肺损伤中的作用

• 批准号: 10720687
• 负责人: Hrishikesh Satish Kulkarni
• 金额: $ 59.85万
• 依托单位: WASHINGTON UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-08-01 至 2027-09-30
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10720687
• 关键词: Acute Lung Injury; Acute Respiratory Distress Syndrome; Address; Affect; Alveolar; Alveolar Macrophages; Area; Binding; Bioinformatics; Biological Assay; Biology; CRISPR screen; Cell Compartmentation; Cell Death; Cell Death Induction; Cell Survival; Cell physiology; Cells; Cessation of life; Characteristics; Circulation; Clustered Regularly Interspaced Short Palindromic Repeats; Compensation; Complement; Complement 3a; Complement 3b; Complement Factor B; Cytoprotection; Data; Dependence; Epithelial Cells; Epithelium; Experimental Models; Extracellular Space; Gene Delivery; Genetic; Goals; Host Defense; Host Defense Mechanism; Human; Immune; Immune response; In Vitro; Inflammatory; Injury; Knock-out; Knockout Mice; Knowledge; Libraries; Liver; Lung; Macrophage; Mediating; Modeling; Morbidity - disease rate; Mus; Myeloid Cells; National Heart, Lung, and Blood Institute; Phagocytosis; Population; Predisposition; Principal Investigator; Process; Production; Proteins; Pseudomonas aeruginosa; Pseudomonas aeruginosa pneumonia; Publishing; Research Personnel; Research Priority; Role; Site; Source; Stress; Testing; Thinking; Time; Tissues; Transgenic Mice; Wild Type Mouse; Work; airway epithelium; alveolar epithelium; cell injury; cell type; complement C3 precursor; complement system; conditional knockout; cytokine; design; disability; extracellular; human model; immune cell infiltrate; improved; in vivo; in vivo Model; lung injury; mortality; mouse model; novel therapeutics; overexpression; pathogen; protective effect; receptor; resilience; response; response to injury; uptake

PROJECT SUMMARY/ABSTRACT The goal of this R01 proposal is to investigate how complement component C3 derived from the lung epithelium can improve host resilience during acute lung injury (ALI) and acute respiratory distress syndrome (ARDS). C3 is a central component of the complement system and one of the most abundant circulatory proteins. It is an early responder to injury and operates by killing pathogens and clearing debris. However, we have shown that it takes time for circulating C3 to reach the alveolar space in ALI, thereby increasing the dependence on C3 present in the lung. We have also shown that not only is lung epithelial cell-derived C3 secreted, but also its intracellular stores are central to the protection against ALI and cell death. These findings are a shift from the conventional thinking that liver-derived C3 is the main operational form of complement in the lung and increases the emphasis on epithelial cells as a source. Additionally, we have shown that many immune cell types—including macrophages—derive C3 stores via uptake from the extracellular space, and this uptake improves their effector response. Hence, this proposal focuses on an emerging role for lung epithelial cell-derived C3 in promoting the survival and function of epithelial cells and macrophages, each one vital in ALI. A major hurdle for investigating tissue-specific roles of complement has been the limited availability of models and assays. We have developed new transgenic mouse models and functional assays that distinguish the roles of liver- and lung-derived complement and show that epithelial cell-derived C3 is central to protection in ALI. We have supplemented these models and assays with data from ex vivo human models to show key roles for C3 in the cellular response to injury. These results support our central hypothesis that lung epithelial cell-derived C3 modulates the bronchoalveolar epithelial and immune cell niche to reduce ALI. This proposal will test our hypothesis by achieving two Specific Aims. Aim 1 compares targeted liver derived C3-deficient mice with lung epithelial cell- derived C3-deficient mice to assess if the cytoprotection offered by lung epithelial cell-derived C3 is cell-type intrinsic or also regional. It will also address how to optimally augment C3 to protect the injured lung. Aim 2 uses a combination of conditional knockout mice and deceased human donor lungs to assess how lung epithelial cell- derived C3 influences the pulmonary myeloid cell compartment, especially alveolar macrophage survival and function. It also addresses how to modulate C3 uptake in these cells to optimize their function. The proposal brings together a principal investigator with expertise in complement biology and acute lung injury, and co-investigators with expertise in gene delivery, CRISPR screens and bioinformatics to determine the immunobiological role of lung epithelial cell-derived C3 in facilitating host defense at the site of injury and promoting tissue resilience. The proposed work is important because understanding how the early host immune response modulates tissue damage is essential for designing and implementing new therapies for ALI. The knowledge will form the basis of locally delivered, host-focused therapies for ARDS, thus aligning with a priority research area for the NHLBI.

项目总结/摘要 本R 01提案的目的是研究补体成分C3如何从肺上皮细胞中衍生 能改善急性肺损伤（ALI）和急性呼吸窘迫综合征（ARDS）时宿主的恢复能力。C3 是补体系统的核心成分，也是最丰富的循环蛋白之一。这是一 早期响应伤害，并通过杀死病原体和清除碎片进行操作。然而，我们已经证明， 在ALI中，循环C3到达肺泡腔需要时间，从而增加了对C3的依赖性 在肺部。我们还表明，不仅肺上皮细胞来源的C3分泌，而且其细胞内 储存是防止ALI和细胞死亡的核心。这些发现是对传统的 认为肝源性C3是补体在肺内的主要运作形式， 作为一种来源。此外，我们已经表明，许多免疫细胞类型，包括 巨噬细胞来源的C3通过从细胞外空间摄取来储存，并且这种摄取提高了它们的效应子 反应因此，该提议集中于肺上皮细胞衍生的C3在促进肺上皮细胞增殖中的新作用。 上皮细胞和巨噬细胞的存活和功能，每一个都在ALI中至关重要。调查的主要障碍是 补体的组织特异性作用一直是模型和测定的有限可用性。我们已经开发 新的转基因小鼠模型和区分肝源性和肺源性的作用的功能测定 补充，并显示上皮细胞衍生的C3是保护ALI的核心。我们补充了这些 使用来自离体人类模型的数据进行模型和测定，以显示C3在细胞应答中的关键作用， 损伤这些结果支持了我们的中心假设，即肺上皮细胞衍生的C3调节了肺上皮细胞的增殖。 支气管肺泡上皮细胞和免疫细胞龛减少ALI。这项提议将通过以下方式检验我们的假设： 实现两个具体目标。目的1比较靶向肝源性C3缺陷小鼠和肺上皮细胞- 衍生的C3缺陷小鼠，以评估肺上皮细胞衍生的C3提供的细胞保护是否为细胞型 内在的或区域的。它还将解决如何最佳地增加C3以保护受伤的肺。Aim 2用途 条件性基因敲除小鼠和已故人类供体肺的组合，以评估肺上皮细胞- 衍生的C3影响肺骨髓细胞室，特别是肺泡巨噬细胞存活， 功能它还涉及如何调节这些细胞中的C3摄取以优化其功能。该提案带来了 以及一名在补体生物学和急性肺损伤方面具有专长的主要研究者和共同研究者 具有基因递送、CRISPR筛选和生物信息学方面的专业知识， 肺上皮细胞衍生的C3在促进损伤部位的宿主防御和促进组织恢复中的作用。的 这项工作很重要，因为了解早期宿主免疫反应如何调节组织 损伤对于设计和实施新的ALI疗法至关重要。这些知识将构成 本地交付，主机为重点的治疗ARDS，从而符合NHLBI的优先研究领域。