Alterations In Pulmonary Immune Function And Host Resistance In COX Null Mice

COX 无效小鼠肺免疫功能和宿主抵抗力的变化

• 批准号: 8553686
• 负责人: Darryl C Zeldin
• 金额: $ 57.44万
• 依托单位: NATIONAL INSTITUTE OF ENVIRONMENTAL HEALTH SCIENCES
• 依托单位国家: 美国
• 资助国家: 美国
• 起止时间: 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/8553686
• 关键词: Acute; Allergens; Allergic; Alveolar Cell; Alveolar Macrophages; Anabolism; Appearance; Attenuated; Biochemical; Bleomycin; Body Temperature Changes; Body Weight; Breathing; Breeding; Bronchoalveolar Lavage Fluid; Bronchoconstriction; CCL17 gene; Cell Adhesion Molecules; Cell Count; Cells; Clara cell; Data; Defect; Dinoprostone; Distal; Endotoxins; Eotaxin; Equilibrium; Exhibits; Fibrosis; Genes; Genotype; Goals; Histopathology; Host resistance; Human; Hydroxyproline; IgE; Immune response; In Vitro; Infection; Inflammation; Inflammatory; Inflammatory Response; Inflammatory Response Pathway; Influenza; Intercellular adhesion molecule 1; Interleukin-13; Interleukin-4; Interleukin-5; Knock-out; Knockout Mice; Leukotriene B4; Leukotrienes; Lipopolysaccharides; Liquid substance; Lung; Lung Compliance; Lung Inflammation; Lymphocyte; MUC5AC gene; Mechanics; Modeling; Mus; Ovalbumin; PTGS2 gene; Pharmaceutical Preparations; Physiological; Prostaglandin Production; Prostaglandin-Endoperoxide Synthase; Prostaglandins; Proteins; Relative (related person); Respiratory physiology; Role; Stimulus; T-Lymphocyte; Transgenes; Transgenic Mice; Trichrome stain; Type II Epithelial Receptor Cell; Up-Regulation; Vascular Cell Adhesion Molecule-1; Viral; Virus Diseases; Wild Type Mouse; airway hyperresponsiveness; allergic airway inflammation; cell type; chemokine; cyclooxygenase 1; cysteinyl-leukotriene; cytokine; environmental agent; eosinophil; immune function; in vivo; indexing; influenzavirus; methacholine; mortality; overexpression; promoter; respiratory; response; vanadium pentoxide

We are investigating the role of cyclooxygenases in basal lung function and in the pulmonary response to environmental agents. At baseline, lung prostaglandin E2 levels are lower in COX-1 null mice compared to either wild type or COX-2 null mice, but there are no significant differences in basal lung function or in lung histopathology between the genotypes. Following allergen (ovalbumin) sensitizationexposure, lung inflammatory indices are significantly greater in COX-1 null and COX-2 null mice compared to wild type mice. Airways of allergic COX-1 null mice have increased numbers of eosinophils and increased numbers of CD3CD4 lymphocytes (Th cells). Alveolar macrophages from allergic COX-1 null airways show biochemical and morphologic evidence of activation. Bronchoalveolar lavage fluid (BALF) from allergic COX-1 null mice contains significantly higher levels of the Th2 cytokines IL-4, IL-5 and IL-13, increased levels of LTB4 and the cysteinyl leukotrienes, and increased levels of the chemokines TARC and eotaxin. These changes in the COX-1 null mice are associated with increased BALF IgE levels and increased MUC5AC productionmucin secretion. Moreover, expression of the adhesion molecules VCAM-1 and ICAM-1 are increased in the lungs of both allergic COX-1 and allergic COX-2 null mice. Allergic COX-1 null mice have reduced lung compliance, increased allergen-induced bronchoconstriction and display hyperresponsiveness to inhaled methacholine. We have also examined the effects of disruption of COX genes on the pulmonary responses to other environmentally relevant agents including inhaled endotoxin (bacterial lipopolysaccharide, LPS), vanadium pentoxide, and influenza virus. Following LPS exposure, all mice exhibit increased bronchoconstriction and methacholine hyperresponsiveness; however, these changes are much more pronounced in both the COX-1 null and COX-2 null mice relative to wild type controls. Interestingly, there are no significant differences in BALF cells or lung histopathology between the genotypes following LPS exposure. Thus, the balance of COX-1 and COX-2 is important in regulating the physiologic but not the inflammatory responses to inhaled LPS. Following vanadium pentoxide (V2O5) exposure, COX-2 null mice, but not COX-1 null mice, have increased acute lung inflammation and develop more lung fibrosis (increased lung hydroxyproline and enhanced trichrome staining). We have also utilized a pulmonary influenza infectivity model to evaluate host resistance and to determine if there are defects in innate or adaptive immune responses to viral infection in COX-1 null and COX-2 null mice. Infection induced less severe illness in COX-2 null mice in comparison to wild type and COX-1 null mice as evidenced by body weight and body temperature changes. Mortality was significantly reduced in COX-2 null mice. COX-1 null mice had enhanced inflammation and earlier appearance of pro-inflammatory cytokines in the BAL fluid, whereas the inflammatory and cytokine responses were blunted in COX-2 null mice. However, lung viral titres were markedly elevated in COX-2 null mice relative to wild type and COX-1 null mice. Levels of prostaglandin E2 were reduced in COX-1 null airways whereas cysteinyl leukotrienes were elevated in COX-2 null airways following infection. Thus, deficiency of COX-1 and COX-2 leads to contrasting effects in the host response to influenza infection, and these differences are associated with altered production of prostaglandins and leukotrienes following infection. The response of COX-deficient mice varies depending on the environmental stimulus. More recently, we developed transgenic mice with lung-specific overexpression of human COX-1 (murine CC10 promoter driven). Whereas no differences in basal respiratory or lung mechanical parameters were observed, COX-1 transgenic mice had increased bronchoalveolar lavage fluid prostaglandin E2 content compared to wild type littermates and exhibited decreased airway responsiveness to inhaled methacholine. In an ovalbumin-induced allergic airway inflammation model, comparable upregulation of COX-2 protein was observed in the lungs of allergic wild-type and COX 1 transgenic mice. Furthermore, no genotype differences were observed in allergic mice in total cell number, eosinophil content and inflammatory cytokine content of bronchoalveolar lavage fluid, or in airway responsiveness to inhaled methacholine. To eliminate the presumed confounding effects of COX-2 upregulation, COX-1 transgenic mice were bred into a COX-2 null background. In these mice, presence of the COX-1 transgene did not alter allergen-induced inflammation but significantly attenuated allergen-induced airway hyperresponsiveness, coincident with reduced airway leukotriene levels. Collectively, these data indicate that COX-1 overexpression attenuates airway responsiveness under basal conditions but does not influence allergic airway inflammation. We are currently developing transgenic mice with overexpression of COX-2 in type II cells (SPA promoter driven) to examine the role of COX-2 in the distal airway. We are also developing mice with selective knockout of COX-2 in the lung (Clara cells, type II alveolar cells) to determine if systemic or local biosynthesis of prostaglandins is important in regulating the lung response to environmental agents. Finally, we are studying the role of COX-1 and COX-2 in differentiation of lung T-cells in vitro and in vivo.

我们正在研究环氧酶在基底肺功能以及对环境剂的肺反应中的作用。在基线时，与野生型或COX-2 NULL小鼠相比，COX-1 NULL小鼠的肺前列腺素E2水平较低，但是基础肺功能或基因型之间的肺组织病理学没有显着差异。与野生型小鼠相比，在过敏原（卵蛋白）敏化暴露曝光下，COX-1 NULL和COX-2 NULL小鼠的肺炎症指标明显更大。过敏性COX-1无效小鼠的气道具有增加的嗜酸性粒细胞和CD3CD4淋巴细胞（TH细胞）的数量增加。来自过敏性COX-1零气道的肺泡巨噬细胞显示生化和形态学的激活证据。来自过敏性COX-1 NULL小鼠的支气管肺泡灌洗液（BALF）含有明显更高的Th2细胞因子IL-4，IL-5和IL-13，LTB4水平升高和Cysteinyl Leukotrienes水平增加，以及趋化因子TARC和Eotaxin的水平增加。 COX-1 NULL小鼠中的这些变化与BALF IgE水平升高和MUC5AC生产 - 糖素分泌有关。此外，在过敏性COX-1和过敏性cox-2 null小鼠的肺中，粘附分子VCAM-1和ICAM-1的表达增加。过敏性COX-1无效小鼠降低了肺依从性，过敏原诱导的支气管收缩并表现出对吸入甲基酸酯的过度反应性。我们还研究了COX基因破坏对其他与环境相关剂的肺反应的影响，包括吸入内毒素（细菌脂多糖，LPS），五氧化钒和流感病毒。 LPS暴露后，所有小鼠均表现出增加的支气管收缩和甲基苯胺高反应性。但是，相对于野生型对照，这些变化在COX-1 NULL和COX-2 NULL小鼠中都更为明显。有趣的是，LPS暴露后的基因型之间的BALF细胞或肺组织病理学没有显着差异。因此，COX-1和COX-2的平衡对于调节生理学而不是对吸入LP的炎症反应很重要。五氧化钒（V2O5）暴露后，COX-2 NULL小鼠，但没有COX-1 NULL小鼠，增加了急性肺部炎症并发展出更多的肺纤维化（增加了肺羟基丙烯酸酯和增强的三晶型染色）。我们还利用了肺流感感染模型来评估宿主的耐药性，并确定COX-1 NULL和COX-2 NULL小鼠的先天或适应性免疫反应缺陷。与体重和体温变化相比，与野生型和COX-1 NULL小鼠相比，感染诱导的COX-2无效小鼠的严重疾病较少。 COX-2无效小鼠的死亡率显着降低。 COX-1 NULL小鼠在BAL液中的炎症增强和促炎性细胞因子的早期出现，而COX-2 NULL小鼠中炎症和细胞因子反应却钝化。 然而，相对于野生型和COX-1 NULL小鼠，在COX-2 NULL小鼠中，肺病毒滴度显着升高。 在感染后，在COX-1空气道中，前列腺素E2的水平降低，而Cox-2 null气道中的白细胞列酮菌则升高。 因此，COX-1和COX-2的缺乏会导致对流感感染的宿主反应的对比作用，并且这些差异与感染后前列腺素和白细胞的产生改变有关。 Cox缺陷小鼠的反应取决于环境刺激。 最近，我们开发了人Cox-1（鼠CC10启动子驱动）的肺特异性过表达的转基因小鼠。尽管与野生型同窝仔相比，观察到基础呼吸道或肺机械参数的差异，但Cox-1转基因小鼠的支气管肺泡灌洗液前列腺素E2含量增加，并且表现出对吸入甲基苯胺的气道反应性降低。 在卵巢蛋白诱导的过敏性气道炎症模型中，在过敏性野生型和COX 1转基因小鼠的肺中观察到COX-2蛋白的可比上调。 此外，在过敏性小鼠中未观察到总细胞数，嗜酸性粒细胞含量和支气管肺泡灌洗液的炎性细胞因子含量，或者在气道对吸入甲基苯胺的反应中。 为了消除COX-2上调的假定混杂作用，将COX-1转基因小鼠育成COX-2无效背景。 在这些小鼠中，COX-1转基因的存在并未改变过敏原诱导的炎症，而是显着减弱了过敏原诱导的气道高反应性，与气道白细胞环境的降低一致。 总的来说，这些数据表明COX-1的过表达减弱了基础条件下的气道反应性，但不会影响过敏性气道炎症。我们目前正在开发具有COX-2过表达II型细胞（SPA启动子驱动）中的转基因小鼠，以检查COX-2在远端气道中的作用。 我们还在肺（Clara细胞，II型肺泡细胞）中选择性敲除COX-2的小鼠，以确定前列腺素的全身或局部生物合成对于调节肺对环境药物的反应是否重要。最后，我们正在研究COX-1和COX-2在体外和体内肺T细胞分化中的作用。