Altered hyaluronan deposition by bronchial epithelial cells contributes to inflammation during respiratory syncytial virus infection

支气管上皮细胞改变的透明质酸沉积导致呼吸道合胞病毒感染期间的炎症

• 批准号: 10418432
• 负责人: STEPHEN R REEVES
• 金额: $ 9.43万
• 依托单位: SEATTLE CHILDREN'S HOSPITAL
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-05-01 至 2024-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10418432
• 关键词: Acute; Adhesions; Adhesives; Alveolus; Attenuated; Binding; Biological Assay; Biological Models; Cell Culture Techniques; Cell Line; Cells; Child; Childhood; Coculture Techniques; Data; Deposition; Epithelial Cells; Extracellular Matrix; Fibroblasts; Future; Genes; Hospitalization; Human; Hyaluronan; Immune; Immune response; Infection; Inflammation; Inflammation Mediators; Inflammatory; Inflammatory Response; Knowledge; Laboratories; Lead; Leukocytes; Lower Respiratory Tract Infection; Lung; Mediating; Modeling; Modification; Molecular; Morbidity - disease rate; Mucous body substance; Neutrophil Activation; Obstruction; Oligonucleotides; Pathologic; Pharmacology; Play; Positioning Attribute; Production; Proteins; Pulmonary Inflammation; Reporting; Respiratory Disease; Respiratory Syncytial Virus Infections; Respiratory Therapy; Respiratory syncytial virus; Role; Shapes; Site; Small Interfering RNA; Source; Stromal Cells; Structure of parenchyma of lung; Submucosa; Supportive care; TNF gene; Techniques; Testing; Therapeutic Intervention; Up-Regulation; Vaccines; Viral Pathogenesis; Viral Respiratory Tract Infection; Virus Diseases; White Blood Cell Count procedure; Work; acute infection; airway inflammation; airway obstruction; bronchial epithelium; cell injury; experimental study; in vivo; inhibitor; knock-down; leukocyte activation; mortality; neutrophil; new therapeutic target; novel; novel therapeutic intervention; novel therapeutics; pathogenic virus; recruit; respiratory virus; response to injury; small hairpin RNA

PROJECT SUMMARY / ABSTRACT Lower respiratory tract infections commonly caused by respiratory syncytial virus (RSV) are a leading cause of hospitalizations and mortality worldwide in young children. Despite many years of study, the mainstay of treatment remains supportive care and currently no RSV specific treatment or vaccine is available. The cells that line the airways, otherwise known as bronchial epithelial cells (BECs), are the primary target for RSV infection. Infection of the BECs with RSV leads to subsequent BEC damage, obstruction of the lower airways with cellular debris and mucous, and the establishment of airway inflammation by recruitment of immune cells such as neutrophils into the peribronchial space. Recent studies from our laboratory have demonstrated that RSV infection of stromal cells such as lung fibroblasts leads to the establishment of an extracellular matrix (ECM) that is enriched with hyaluronan (HA) which promotes the accumulation and activation of leukocytes in ex vivo cell culture models. Furthermore, we found that the increased HA accumulation following RSV infection was more closely associated with the fibroblast cell layer and displayed greater modification with heavy chains (HC) which has been described in other studies to enhance the ECM’s ability to become sticky for inflammatory cells and promotes the inflammatory response in the lung. The formation of HC-HA is the result of the enzymatic activity of tumor necrosis factor stimulated gene 6 (TSG-6), which is not normally expressed in healthy lung tissue, but is induced in response to injury. In our previous work with lung fibroblasts, we have shown that TSG-6 is upregulated during RSV infection and blocking its induction with siRNA decreased the amount of HC-HA that was formed and decreased the accumulation of leukocytes. Despite being the primary target of RSV infection, no studies exist that have evaluated the effects of RSV infection on BEC production of HA or TSG-6 induced HC-HA formation despite the important role that HC-HA plays in promoting lung inflammation. Our laboratory both has expertise in the characterization of HA matrices and access to primary human BECs from well-characterized pediatric donors placing our group in a unique position to evaluate the contribution of BEC derived HC-HA to the inflammatory response following RSV infection. We hypothesize that RSV infection of BECs leads to increased production and accumulation of HA which will in turn promote the accumulation and activation of neutrophils in an ex vivo human cell culture model system. Additionally, we will test the hypothesis that RSV infection of BECs will induce the expression of TSG-6 thereby promoting the formation of HC-HA and further drive the accumulation and activation of neutrophils in our model system. We will pharmacologically block the formation of HC-HA enriched ECMs and also block the induction of TSG-6 during RSV infection in order to establish whether the increased accumulation of the neutrophils is HC-HA dependent. If true, characterizing the importance of HC-HA produced by BECs may lead to novel targets for therapeutic intervention during acute RSV infections and may be applicable to other respiratory viruses.

项目摘要/摘要 通常由呼吸道合胞病毒(RSV)引起的下呼吸道感染是导致 全球幼儿住院率和死亡率。尽管经过了多年的研究，但 治疗仍然是支持性护理，目前还没有RSV特异性治疗或疫苗可用。这些细胞 呼吸道上皮细胞(BECs)是呼吸道合胞病毒的主要目标。 感染。呼吸道合胞病毒感染BECs会导致BEC受损，下呼吸道阻塞。 通过细胞碎片和粘液，以及通过招募免疫细胞来建立呼吸道炎症 如中性粒细胞进入支气管腔。我们实验室最近的研究表明， 呼吸道合胞病毒感染肺成纤维细胞等基质细胞导致细胞外基质的建立 (ECM)富含透明质酸(HA)，促进白细胞在体内的积累和激活 体外细胞培养模型。此外，我们还发现RSV感染后HA蓄积增加 与成纤维细胞层联系更紧密，显示出更大的重链修饰 (HC)在其他研究中描述的增强ECM变得粘性的能力 炎症细胞，促进肺部的炎症反应。其结果是HC-HA的形成 非正常表达的肿瘤坏死因子刺激基因6(TSG-6)的酶活性 在健康的肺组织中，但在损伤后被诱导。在我们之前对肺成纤维细胞的研究中，我们有 研究表明，在RSV感染过程中TSG-6表达上调，用siRNA阻断其诱导可降低 产生大量的HC-HA，减少白细胞的聚集。尽管是初选 作为RSV感染的靶标，目前还没有研究评估RSV感染对BEC产生的影响 HA或TSG-6诱导HC-HA的形成，尽管HC-HA具有重要的促肺作用 发炎。我们的实验室既有HA基质表征方面的专业知识，也有机会获得初级 来自具有良好特征的儿科捐赠者的人类BEC使我们的团队处于独特的位置来评估 BEC来源的HC-HA在RSV感染后炎症反应中的作用我们假设 呼吸道合胞病毒感染BECs导致HA的产生和积累增加，进而促进BECs 中性粒细胞在体外人体细胞培养模型系统中的积累和激活。此外，我们还将 验证RSV感染BECs会诱导TSG-6表达从而促进BECs 在我们的模型系统中，HC-HA的形成和进一步驱动中性粒细胞的积累和激活。我们 会不会从药理上阻断富含HC-HA的ECM的形成，并阻断TSG-6的诱导 以确定中性粒细胞聚集增加是否是HC-HA 依附的。如果是真的，表征BEC产生的HC-HA的重要性可能会导致新的靶点 在急性呼吸道合胞病毒感染期间的治疗干预，并可能适用于其他呼吸道病毒。