Role of Pollen Oxidase Induced ROS on Allergic Asthma

吸入花粉会导致过敏性炎症和过敏受试者肺部粘液的产生。“过敏性”花粉含有“主要抗原蛋白”，如豚草中的Amba1。此外，它们还有许多其他蛋白质，其中一些具有酶活性。一个重要的悬而未决的问题是，花粉中的这些酶活性是否会影响主要花粉抗原引起的变态反应性炎症。我们发现所有测试的花粉都具有内在的NADPH氧化酶活性。用花粉提取物攻击在几分钟内就会在肺部诱导氧化应激，并伴随着GSSG(氧化谷胱甘肽)和4-HNE(过氧化脂质)的产生。我们的中心假设是GSSG和4-HNE是由呼吸道衬里液体中的内源性花粉NADPH氧化酶产生的，与适应性免疫无关。这些分子被认为是一个“危险信号”，导致p38蛋白激酶等信号通路的激活，以及促炎细胞因子和趋化因子的产生，从而将炎性细胞招募到呼吸道。这些被招募的亲过敏炎症细胞促进了主要花粉抗原在呼吸道中诱导Th2表型。在这里，我们建议1)鉴定和定量GSSG和4-HNE诱导的肺内不依赖适应性免疫的促炎基因，并确定这些基因在招募亲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 3)测试p38 MAPK异构体在介导GSSG和4-HNE诱导的基因产物中的作用，该基因产物促进亲过敏炎症细胞的运输，并增加呼吸道上皮细胞粘蛋白的产生。目前，过敏人群中主要花粉抗原的提呈被认为是诱发变态反应性炎症的唯一机制。我们建议GSSG和4-HNE的产生与抗原提呈协同作用，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，这些想法基于 抑制肺中基于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.