Role of Pollen Oxidase Induced ROS on Allergic Asthma

吸入花粉会引起过敏性炎症并在过敏性受试者的肺部产生粘液。 “致敏”花粉含有“主要抗原蛋白”，例如豚草中的 Amb a 1。此外，它们还有许多其他蛋白质，其中一些具有酶活性。一个重要的未解决问题是花粉内的这些酶活性是否影响主要花粉抗原诱导的过敏性炎症。我们发现所有测试的花粉都具有内在的 NADPH 氧化酶活性。花粉提取物的刺激会在几分钟内引起肺部氧化应激，并与 GSSG（氧化型谷胱甘肽）和 4-HNE（过氧化脂质）的生成相关。我们的中心假设是 GSSG 和 4-HNE 是由气道内壁液体中的内在花粉 NADPH 氧化酶产生的，与适应性免疫无关。这些分子被视为“危险信号”，导致 p38 MAP 激酶等信号通路的激活，并产生促炎细胞因子和趋化因子，将炎症细胞招募到气道中。这些募集的促过敏炎症细胞促进主要花粉抗原在气道中诱导 Th2 表型。在这里，我们建议：1) 鉴定和量化肺部中 GSSG 和 4-HNE 诱导的独立于适应性免疫的促炎症基因，并确定这些基因在募集促过敏炎症细胞中的作用； 2) 测试GSSG和4-HNE提供第二信号的能力 增强致敏小鼠中主要花粉抗原诱导的过敏性气道炎症，并增强初始小鼠的过敏性致敏； 3) 测试 p38 MAPK 同工型在介导 GSSG 和 4-HNE 诱导基因产物中的作用，这些基因产物促进促过敏性炎症细胞的运输并增加气道上皮细胞中粘蛋白的产生。目前，过敏人中主要花粉抗原的抗原呈递被认为是诱导过敏性炎症的唯一机制。我们建议 GSSG 和 4-HNE 的产生与抗原呈递协同作用，以增强过敏性炎症。这些研究可能会为过敏性哮喘患者产生新的治疗思路，其基础是 抑制肺部基于 GSSG 和 4-HNE 的信号通路。

Inhalation of pollens induces allergic inflammation and mucus production in the lungs of allergic subjects. "Allergenic" pollens have "major antigenic proteins" such as Amb a 1 in ragweed. In addition, they have many other proteins, some with enzyme activities. An important unresolved question is whether these enzyme activities within pollens influences allergic inflammation induced by the major pollen antigen. We have discovered that all tested pollens have intrinsic NADPH oxidase activity. Challenge with pollen extract induces oxidative stress in the lungs within minutes, associated with generation of GSSG (oxidized glutathione) and 4-HNE (lipid peroxide). Our central hypothesis is that GSSG and 4-HNE are generated by intrinsic pollen NADPH oxidases in the airway lining fluid independent of adaptive immunity. These molecules are perceived as a "Danger signal", leading to activation of signaling pathways such as p38 MAP kinases, and production of pro-inflammatory cytokines and chemokines that recruit inflammatory cells into the airways. These recruited pro-allergic inflammatory cells facilitate induction of Th2 phenotype in the airways by major pollen antigen. Here we propose to 1) Identify and quantify pro-inflammatory genes induced by GSSG and 4-HNE in the lungs independent of adaptive immunity, and determine the role of these genes in recruiting pro-allergic inflammatory cells; 2) Test the ability of GSSG and 4-HNE to provide a second signal that potentiates allergic airway inflammation induced by major pollen antigen in sensitized mice, and boosts allergic sensitization in naive mice; 3) Test the role of p38 MAPK isoforms in mediating induction of gene products by GSSG and 4-HNE that facilitates trafficking of pro-allergic inflammatory cells and augment mucin production in airway epithelial cells. At present, antigen presentation of major pollen antigen in allergic persons is thought to be to sole mechanism of induction of allergic inflammation. We propose that generation of GSSG and 4-HNE acts in concert with antigen presentation to augment allergic inflammation. These studies are likely to generate new therapeutic ideas for patients with allergic asthma that are based on suppression of GSSG and 4-HNE based signaling pathways in the lungs.