Role of the Respiratory Syncytial Virus Fusion Protein in Airway Mucus Induction

呼吸道合胞病毒融合蛋白在气道粘液诱导中的作用

• 批准号: 8462893
• 负责人: Martin Lawrence Moore
• 金额: $ 35.98万
• 依托单位: EMORY UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-05-15 至 2015-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8462893
• 关键词: Amino Acids; Automobile Driving; Basophils; Biological Assay; Bronchiolitis; Cell Line; Cells; Cessation of life; Chimeric Proteins; Data; Epithelial; Epithelial Cells; Functional disorder; Genes; Giant Cells; Goals; Hospitalization; Human; Hypoxia; Immune response; In Vitro; Inbred BALB C Mice; Infant; Infection; Inflammatory; Interleukin-13; Interleukin-4; Laboratories; Lead; Lower respiratory tract structure; Lung; Measures; Mechanical ventilation; Mediating; Modeling; Molecular Models; Mucins; Mucous body substance; Mus; Mutagenesis; Neutrophilia; Pathogenesis; Play; Production; Proteins; Respiratory Syncytial Virus Infections; Respiratory syncytial virus; Role; System; T-Lymphocyte; Transfection; Viral; Viral Bronchiolitis; Viral Fusion Proteins; Viral Load result; Virulence; Virulent; Virus; Virus Diseases; airway hyperresponsiveness; airway obstruction; base; cell injury; cell type; cytokine; in vivo; innovation; molecular modeling; mutant; neutrophil; positional cloning; public health relevance; research study; response; virus pathogenesis

DESCRIPTION (provided by applicant): Our long term goal is to elucidate mechanisms by which respiratory syncytial virus (RSV) causes lung dysfunction. In the USA, RSV hospitalizes >100K infants/year. Pulmonary mucus is a hallmark of RSV disease. Mucus mixed with epithelial cell debris blocks the airways. Mechanisms by which RSV infection induces airway mucus are not known. Goals of this proposal are to define the role of the viral fusion (F) proteins of mucus-inducing RSV strains in pathogenesis and to define the roles of neutrophils and basophils in RSV-induced mucus. In contrast to laboratory RSV strains, RSV strains line 19 and 2-20 induce mucus and bronchiolitis in mice. Using a RSV reverse genetics system, we showed that the F protein of line 19 plays a role in mucus induction. We identified five amino acids in the line 19 F protein as candidates for involvement in mucus induction. We will use F mutant viruses to define line 19 F residues that are important for mucus expression in vivo. RSV 2- 20 is virulent in mice. We hypothesize that RSV 2-20 F contributes to airway mucus and virulence. We will define the role of 2-20 F in pathogenesis using 2-20F-chimeric RSV. Line 19 and 2-20 cause greater epithelial cell cytopathic effect (CPE) and desquamation in vivo than lab RSV strains. We will use F mutants to define effects of RSV line 19 F and 2-20 F on epithelial cell CPE, syncytia, and desquamation in vivo and in vitro. We will define the fusogenicity of RSV line 19, 2-20, and lab strain F proteins in epithelial cells in vitro using a fusion assay. We hypothesize that line 19 F and 2-20 F induce greater syncytia and fusion in vivo and in vitro. The study will also determine the roles of neutrophils and basophils in RSV bronchiolitis. Concurrently wih epithelial cell damage, RSV line 19 and 2-20 induce neutrophilia in the lungs of mice. We hypothesize that neutrophils contribute to viral clearance and mucus expression in line 19 and 2-20 pathogenesis. Line 19- induced mucus is dependent on IL-13, a TH2 cytokine. IL 4 is the primary TH2-driving cytokine. We showed that basophils are the major IL 4-expressing cell type in RSV-infection. We hypothesize that basophils contribute to RSV line 19- and 2-20-induced IL-13 and mucus expression. These RSV bronchiolitis models will advance our understanding of RSV strain-dependent pathogenesis and may lead to much-needed therapies.

描述（由申请人提供）：我们的长期目标是阐明呼吸道合胞病毒（RSV）引起肺功能障碍的机制。在美国，每年有10万婴儿因呼吸道合胞病毒住院。肺粘液是呼吸道合胞病毒病的标志。与上皮细胞碎片混合的粘液阻塞了气道。RSV感染诱导气道粘液的机制尚不清楚。本研究的目的是确定诱导粘液的RSV菌株的病毒融合蛋白在发病机制中的作用，并确定中性粒细胞和嗜碱性粒细胞在RSV诱导的粘液中的作用。与实验室RSV菌株相比，RSV株19和2-20在小鼠中诱导粘液和细支气管炎。利用RSV反向遗传系统，我们发现19号系的F蛋白在粘液诱导中起作用。我们在line19f蛋白中确定了5个氨基酸作为参与粘液诱导的候选氨基酸。我们将使用F突变病毒来定义对体内粘液表达很重要的第19行F残基。RSV 2- 20对小鼠有毒性。我们假设RSV 2- 20f与气道粘液和毒力有关。我们将利用2- 20f嵌合RSV确定2- 20f在发病机制中的作用。Line 19和2-20在体内比实验室RSV毒株引起更大的上皮细胞病变效应（CPE）和脱屑。我们将使用F突变体来确定RSV细胞系19f和2- 20f在体内和体外对上皮细胞CPE、合胞体和脱屑的影响。我们将通过融合实验确定RSV细胞系19,2 -20和实验室菌株F蛋白在体外上皮细胞中的融合性。我们假设19f和2- 20f在体内和体外诱导了更大的合胞体和融合。该研究还将确定中性粒细胞和嗜碱性粒细胞在RSV细支气管炎中的作用。在上皮细胞损伤的同时，RSV 19系和2-20系可诱导小鼠肺部嗜中性粒细胞增多。我们假设中性粒细胞在line19和2-20的发病机制中参与病毒清除和粘液表达。Line 19诱导的黏液依赖于IL-13，一种TH2细胞因子。IL - 4是主要的th2驱动细胞因子。我们发现嗜碱性细胞是rsv感染中主要表达IL - 4的细胞类型。我们假设嗜碱性细胞参与RSV细胞系19-和2-20诱导的IL-13和粘液表达。这些RSV细支气管炎模型将促进我们对RSV菌株依赖的发病机制的理解，并可能导致急需的治疗。