Lung-derived complement in pneumonia

肺炎中的肺源性补体

• 批准号: 10568567
• 负责人: Hrishikesh Satish Kulkarni
• 金额: $ 54.37万
• 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: 2023-05-19 至 2028-04-30
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10568567
• 关键词: Acute; Acute Pneumonia; Address; Anabolism; Area; Attenuated; Bacteremia; Bacteria; Bacterial Infections; Bacterial Pneumonia; Binding; Biochemical; Biological Assay; Bronchopneumonia; CRISPR screen; Cause of Death; Cell Death; Cell Death Induction; Cell Survival; Cell secretion; Cells; Cessation of life; Circulation; Clustered Regularly Interspaced Short Palindromic Repeats; Complement; Complement 3 Convertase; Complement 3a; Complement 3b; Complement Activation; Complement Factor B; Cytoprotection; Data; Deposition; Enzymes; Epithelial Cells; Epithelium; Gene Delivery; Genetic; Goals; Host Defense; Host Defense Mechanism; Human; Immune response; In Vitro; Individual; Infection; Inflammatory Response; Knock-out; Knowledge; Libraries; Ligands; Liquid substance; Liver; Lung; Mediating; Modeling; Molecular; Morbidity - disease rate; Mucous Membrane; Mus; National Heart, Lung, and Blood Institute; Pathway interactions; Pattern; Plasmids; Pneumonia; Predisposition; Proteins; Proteomics; Pseudomonas aeruginosa; Pseudomonas aeruginosa infection; Pseudomonas aeruginosa pneumonia; Reporting; Research; Research Priority; Role; Severities; Site; Source; Stress; Structure-Activity Relationship; Surface; Testing; Tissues; Transfection; Transgenic Mice; Work; airway epithelium; alveolar epithelium; arm; cell injury; cellular imaging; complement system; design; gene therapy; human model; humoral immunity deficiency; improved; in vivo; knowledge integration; lung injury; mortality; mouse model; mutant; novel; novel therapeutics; overexpression; oxidant stress; pathogen; pathogenic bacteria; pharmacologic; pneumonia treatment; protective effect; protein transport; pulmonary function; receptor; resilience; uptake; working group

PROJECT ABSTRACT The objective of this R01 proposal is to investigate the function of lung-derived complement proteins and harness their activities to mitigate the severity of pneumonia. Complement proteins C3 and Factor B (FB) comprise an early arm of the host immune response. They are primarily derived from the liver and function in the circulation by killing pathogens such as bacteria. However, our recent work has demonstrated the importance of local C3 expression in lung epithelial cell survival during stress. This proposal focuses on an emerging role for lung- derived FB, a ligand for C3, in reducing excessive tissue damage in the setting of an acute bacterial pneumonia. Our goal is to determine how FB promotes pulmonary host defense. We will investigate sources of FB in the lung and establish its putative protective effect relative to C3. A major hurdle for investigating tissue-specific roles of complement has been the limited availability of models and assays. We have developed novel transgenic mouse models and functional assays that distinguish the roles of liver- and lung-derived complement proteins, and specifically identify the role of lung-derived FB in pneumonia. Our mouse models are supplemented with data from in vitro human models that demonstrate the role of FB to protect against stress-induced epithelial cell death. Additionally, CRISPR-induced deletion of cell-derived complement proteins suggests active internalization of exogenous complement proteins. These combined results support our central hypothesis that lung-derived FB promotes host defense by mitigating epithelial cell death. This proposal will test our hypothesis by achieving two Specific Aims. Aim 1 compares global FB-deficient, targeted liver FB-deficient, and lung epithelial cell-derived FB-deficient mice to assess how lung-derived FB mitigates acute bronchopneumonia severity and cell death. We also will assess if augmenting FB in the lung using pharmacological and gene delivery approaches protects against pneumonia. Aim 2 analyzes whether lung-derived, intracellular FB activity mitigates cell death in vitro by leveraging a combination of human primary lung epithelial cells and FB-deficient cells to dissect the molecular and biochemical mechanisms responsible for complement function in the lung. The proposal integrates knowledge of pulmonary complement activation, intracellular complement protein trafficking, and structure-function relationships with gene therapy, cell imaging, proteomics, and CRISPR screens to determine how lung-derived FB promotes epithelial cytoprotection during stress. These approaches are independent but complementary for investigating the immunobiological role of lung-derived FB in mucosal barrier protection of the lung. The proposed work is important because understanding how the early host immune response modulates tissue damage is essential for designing and implementing urgently needed, new therapies for pneumonia. Thus, we will assess how lung-derived FB facilitates host defense at the site of infection and promotes tissue resilience. These efforts will help our long-term goal of developing a novel host-focused therapy for pneumonia, thus aligning with a priority area of the NHLBI Working Group Report on pneumonia research.

项目摘要 该R 01提案的目的是研究肺源性补体蛋白的功能， 他们的活动，以减轻肺炎的严重程度。补体蛋白C3和因子B（FB）包含一个补体受体。 宿主免疫反应的早期阶段。它们主要来自肝脏，在循环中发挥作用 通过杀死病原体如细菌。然而，我们最近的工作已经证明了本地C3的重要性， 在应激期间肺上皮细胞存活中的表达。这一建议的重点是肺的新兴作用- 衍生的FB，C3的配体，在急性细菌性肺炎的情况下减少过度的组织损伤。 我们的目标是确定FB如何促进肺部宿主防御。我们将调查FB的来源 肺，并建立其相对于C3的推定保护作用。研究组织特异性的主要障碍是 补体的作用一直是模型和测定的有限可用性。我们开发了一种新的转基因 小鼠模型和区分肝源性和肺源性补体蛋白的作用的功能测定， 明确肺源性FB在肺炎中的作用。我们的小鼠模型补充了 来自体外人类模型的数据，这些数据证明FB在保护免受应激诱导的上皮细胞中的作用。 死亡此外，CRISPR诱导的细胞来源的补体蛋白的缺失表明活性补体蛋白的存在。 外源补体蛋白的内化。这些综合结果支持了我们的中心假设， 肺源性FB通过减轻上皮细胞死亡促进宿主防御。这项提案将考验我们的 实现两个具体目标。目的1比较了整体FB缺乏、靶向肝脏FB缺乏和 肺上皮细胞来源的FB缺陷小鼠，以评估肺来源的FB如何减轻急性支气管肺炎 严重性和细胞死亡。我们还将评估是否使用药物和基因递送在肺中增加FB 预防肺炎的方法。目的2分析肺源性细胞内FB活性是否减轻 通过利用人原代肺上皮细胞和FB缺陷细胞的组合， 剖析负责肺中补体功能的分子和生物化学机制。的 该提案整合了肺补体激活，细胞内补体蛋白运输， 以及与基因治疗、细胞成像、蛋白质组学和CRISPR筛选的结构-功能关系， 确定肺源性FB如何在应激期间促进上皮细胞保护。这些方法 独立但互补的研究肺源性FB在粘膜屏障中的免疫生物学作用 保护肺部。这项工作很重要，因为了解早期宿主免疫是如何发生的。 反应调节组织损伤对于设计和实施迫切需要的新疗法至关重要 治疗肺炎因此，我们将评估肺源性FB如何促进感染部位的宿主防御， 促进组织弹性。这些努力将有助于我们开发一种新型宿主聚焦疗法的长期目标 因此，与NHLBI工作组关于肺炎研究的报告的优先领域保持一致。