IL-18 Signaling and Lung Epithelial Cell Barrier Integrity in Severe Asthma

严重哮喘中的 IL-18 信号传导和肺上皮细胞屏障完整性

• 批准号: 9758736
• 负责人: Matthew Camiolo
• 金额: $ 7.22万
• 依托单位: UNIVERSITY OF PITTSBURGH AT PITTSBURGH
• 依托单位国家: 美国
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-12-01 至 2021-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9758736
• 关键词: Address; Adherens Junction; Adrenal Cortex Hormones; Affect; Air; Allergens; Antigens; Asthma; Automobile Driving; Biological Assay; Biological Markers; Biology; Biopsy; Biopsy Specimen; Bronchoalveolar Lavage; Cells; Collection; Computational Biology; Cost of Illness; Data; Data Set; Disease; E-Cadherin; Electrical Resistance; Enzyme-Linked Immunosorbent Assay; Epithelial; Epithelial Cells; Epithelium; Event; Exhibits; Exposure to; Foundations; Functional disorder; Future; Genes; Heterogeneity; Housing; Human; IL18 gene; Immune; Immunofluorescence Microscopy; Immunohistochemistry; Immunology; Impairment; In Vitro; Inflammation; Inflammatory; Interleukin-18; JUN gene; Ligands; Link; Liquid substance; Lung; MAP Kinase Gene; MAPK14 gene; MAPK8 gene; Machine Learning; Measures; Mucous Membrane; Ontology; Pathogenesis; Pathway interactions; Patients; Permeability; Phenotype; Play; Positioning Attribute; Proteins; Pulmonary function tests; Quality of life; Recording of previous events; Refractory; Research; Research Personnel; Resources; Respiratory physiology; Risk; Role; Serum; Severity of illness; Signal Pathway; Signal Transduction; Source; Specimen; Sputum; Stains; Structure; Techniques; Tight Junctions; Tissue Banks; Tissues; Transcript; Transcription Factor AP-1; Treatment Cost; Universities; Validation; Variant; Western Blotting; Work; airway epithelium; asthma exacerbation; asthmatic; asthmatic airway; asthmatic patient; base; bronchial epithelium; clinical phenotype; cofactor; cohort; cytokine; experience; genetic signature; genome wide association study; in vivo; interleukin-18 receptor; novel; occludin; pathogen; patient subsets; programs; response; standard care; success; transcriptome sequencing

PROJECT SUMMARY/ABSTRACT: Asthma is a common disease, affecting more than 300 million people worldwide. Though well controlled in most, some experience disease that is refractory to standard treatments such as corticosteroids. Recent efforts focused on understanding these severe asthma (SA) patients suggests ontological heterogeneity. Previous work from the Severe Asthma Research Program (SARP) cohort linked epithelial gene signature to clinical phenotype. We revisited this data set and identified 3 novel groups of asthmatics, one of which housing the majority of SA cases and having the worst lung function and greatest exacerbation history. Using principal drivers of variance in the data set, we found that expression of the interleukin 18 receptor (IL18R1) along with 18 other genes was able identify at-risk asthmatics. IL18R1 has been previously linked to asthma in genome-wide association studies. Its ligand, interleukin-18 (IL-18), may be a cofactor for both Th1 and Th2 inflammation. High IL-18 levels have been detected in serum and sputum of asthmatics including in those with fatal asthma. Importantly, IL-18 and IL18R1 regulate epithelial barrier function in other inflammatory conditions. We have confirmed an increase in IL18R1 at the protein level in SA patients compared to healthy controls (HC) using lung biopsies from very severe asthma cases. These SA patients also harbor increased numbers IL-18+ cells, the cognate ligand for IL18R1. Downstream targets of IL18 stimulation, including the active phosphorylated forms of JNK1 and c-Jun, show increase in SA airway epithelium. SA patients also show disorganization of adherens junctions, suggesting breakdown in epithelial barrier integrity. Based on this background and our preliminary data, we hypothesize that IL-18 pathway activation, via elevated IL18R1 expression in bronchial epithelium, promotes dysregulated barrier function that contributes to SA pathobiology by increasing immune cell access to foreign antigens. We propose 2 aims to address this: Aim 1. We will interrogate pre-existing tissue banks for quantitative analysis of IL18R1 and compare that with levels of its ligand in tissue and fluids from these patients. These data will be corroborated with activity of associated signaling pathways and tight/adherens junction integrity. Aim 2. We will us primary human airway epithelial cells, obtained bronchoscopically from HCs and asthmatic patients to mechanistically confirm and expand upon the results from Aim 1. This will include validation of ex vivo results as well as quantification of barrier function. These data will identify a novel role for IL18 in severe asthma pathogenesis and open up new avenues for treatment of this difficult and costly disease. The activities of the project will provide the PI with valuable experience in obtaining, culturing and manipulating primary human airway epithelial cells and lay the foundation for future in vivo work by integrating study in computational biology and immunology.

项目摘要/摘要： 哮喘是一种常见疾病，影响全球超过 3 亿人。虽然控制得很好 在大多数情况下，有些人患有皮质类固醇等标准治疗难以治愈的疾病。最近的 专注于了解这些严重哮喘（SA）患者的努力表明存在本体异质性。 严重哮喘研究计划 (SARP) 队列之前的工作将上皮基因特征与 临床表型。我们重新审视了这个数据集并确定了 3 个新的哮喘患者群体，其中一组 居住着大多数 SA 病例，肺功能最差，病情恶化史最严重。使用 数据集中方差的主要驱动因素，我们发现白细胞介素 18 受体 (IL18R1) 的表达 与其他 18 个基因一起能够识别高危哮喘患者。 IL18R1 先前已被证实与哮喘相关 全基因组关联研究。其配体白介素 18 (IL-18) 可能是 Th1 和 Th2 的辅助因子 炎。在哮喘患者（包括患有哮喘的患者）的血清和痰液中检测到高 IL-18 水平 致命的哮喘。重要的是，IL-18 和 IL18R1 在其他炎症中调节上皮屏障功能 状况。我们已经证实，与健康人相比，SA 患者的 IL18R1 蛋白水平有所增加 对照（HC）使用来自非常严重的哮喘病例的肺活检。这些 SA 患者还具有增加的 IL-18+ 细胞的编号，IL-18R1 的同源配体。 IL18 刺激的下游靶标，包括 JNK1 和 c-Jun 的活性磷酸化形式显示 SA 气道上皮细胞增加。 SA患者还 显示粘附连接的混乱，表明上皮屏障完整性的破坏。 基于这一背景和我们的初步数据，我们假设 IL-18 通路激活通过 支气管上皮中 IL18R1 表达升高，促进屏障功能失调，从而导致 SA 病理学通过增加免疫细胞接触外来抗原来实现。我们提出 2 个目标来解决这个问题： 目标 1. 我们将询问现有的组织库以进行 IL18R1 的定量分析，并将其与 这些患者的组织和体液中其配体的水平。这些数据将与以下活动得到证实 相关信号通路和紧密/粘附连接完整性。 目标 2. 我们将使用通过支气管镜从 HC 和哮喘患者获得的原代人气道上皮细胞 患者机械地确认并扩展目标 1 的结果。这将包括前验证 体内结果以及屏障功能的量化。 这些数据将确定 IL18 在严重哮喘发病机制中的新作用并开辟新途径 用于治疗这种困难且昂贵的疾病。该项目的活动将为 PI 提供有价值的信息 获得、培养和操作原代人气道上皮细胞的经验，奠定了 通过整合计算生物学和免疫学研究，为未来体内工作奠定基础。