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.

项目概要/摘要 下呼吸道感染通常由呼吸道合胞病毒（RSV）引起，是导致以下疾病的主要原因 尽管经过多年的研究，世界范围内幼儿的住院率和死亡率仍然是主要的。 治疗仍然是支持性护理，目前没有 RSV 特异性治疗或疫苗可用。 呼吸道内的细胞，也称为支气管上皮细胞 (BEC)，是 RSV 的主要目标 RSV 感染 BEC 会导致随后的 BEC 损伤、下呼吸道阻塞。 细胞碎片和粘液，并通过招募免疫细胞建立空气炎症通道 我们实验室最近的研究表明，中性粒细胞进入支气管周围空间。 RSV 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)，可促进白细胞的积累和活化 此外，我们发现 RSV 感染后 HA 积累增加。 与成纤维细胞层的联系更紧密，并显示出更大的重链修饰 (HC) 在其他研究中已被描述为增强 ECM 的粘性能力 炎症细胞并促进肺部炎症反应，从而形成HC-HA。 肿瘤坏死因子刺激基因 6 (TSG-6) 的酶活性，该基因正常情况下不表达 存在于健康的肺组织中，但它是由损伤引起的。在我们之前对肺成纤维细胞的研究中，我们发现 结果表明，TSG-6 在 RSV 感染期间上调，用 siRNA 阻断其诱导可降低 尽管是主要的，但形成的 HC-HA 量减少了白细胞的积累。 RSV 感染的目标，目前尚无研究评估 RSV 感染对 BEC 产生的影响 尽管 HC-HA 在促进肺功能方面发挥重要作用，但 HA 或 TSG-6 仍诱导 HC-HA 形成 我们的实验室在 HA 基质的表征和获得原发性方面都拥有专业知识。 来自特征明确的儿科捐赠者的人类 BEC 使我们的团队处于独特的地位来评估 BEC 衍生的 HC-HA 对 RSV 感染后炎症反应的贡献。 BECs 的 RSV 感染导致 HA 的产生和积累增加，进而促进 此外，我们将在离体人类细胞培养模型系统中积累和激活中性粒细胞。 检验 RSV 感染 BEC 会诱导 TSG-6 表达从而促进 BEC 的假设 HC-HA 的形成并进一步驱动我们模型系统中中性粒细胞的积累和激活。 将在药理学上阻断富含 HC-HA 的 ECM 的形成，并阻断 TSG-6 的诱导 RSV 感染期间，以确定中性粒细胞积累的增加是否为 HC-HA 如果属实，表征 BEC 产生的 HC-HA 的重要性可能会导致新的目标。 急性RSV感染期间的干预和治疗可能适用于其他呼吸道病毒。