Eicosanoid Production By Infected Lung Epithelial Cells

描述（由申请人提供）：粘膜表面的炎症机制一直是我在过去9年的研究生和研究生学习中的主要焦点。嗜中性粒细胞（PMN）向气道粘膜的募集是诸如肺炎、囊性纤维化和慢性阻塞性肺病等疾病的病理学标志。我正在研究一种新的炎症途径，使用体外模型，包括肺上皮细胞生长在Transwell过滤器和分离的人中性粒细胞。在该模型中，肺上皮细胞的细菌感染引起PMN化学引诱物的上皮分泌，其引导PMN穿过上皮细胞。 在我的博士后培训期间，我们将这种PMN化学引诱剂鉴定为类花生酸，hepoxilin A3（HXA 3）。该提案描绘了一种有针对性的方法来识别受感染肺上皮中负责HXA 3合成的酶。具体而言，将分析磷脂酶A2（PLA 2）和12-脂氧合酶（12-LO）。PLA 2酶主要负责生成花生四烯酸，花生四烯酸是所有类花生酸的前体，12-LO介导花生四烯酸转化为HXA 3。肺上皮细胞和病原菌都具有PLA 2活性，我们将研究每种PLA 2来源对HXA 3产生的贡献。未来的研究将使用更复杂和/或更疾病相关的模型来评估HXA 3的作用，例如气液界面培养、CFTR突变上皮细胞、与上皮-内皮单层的共培养、全组织和整个动物。此外，一个重要的未来考虑因素涉及分析粘膜炎性疾病患者的组织，以确定是否观察到HXA 3产生关键酶的表达增加。对这种未探索的途径的彻底理解将导致选择性地阻断HXA 3产生的策略。我的长期职业目标是开发治疗粘膜表面破坏性炎症的疗法。可能受益于这种治疗策略的疾病并不局限于肺部。 皮肤、泌尿生殖道和肠道的感染，以及特发性疾病如银屑病和炎性肠病，都在上皮表面共享破坏性PMN浸润，并可能涉及HXA 3产生的失调。这些研究可能最终导致开发出一系列全新的抗炎药物，对广泛的病理学具有疗效

DESCRIPTION (provided by applicant): Inflammatory mechanisms at mucosal surfaces have been a major focus over the past 9 years during my graduate and post-graduate studies. Recruitment of neutrophils (PMNs) to the airway mucosa is a pathological hallmark of diseases such as pneumonia, cystic fibrosis and chronic obstructive pulmonary disease. I am investigating a novel inflammatory pathway using an in vitro model consisting of lung epithelial cells grown on Transwell filters and isolated human PMNs. In this model, bacterial infection of lung epithelia cause epithelial secretion of a PMN chemo-attractant, which directs PMNs to cross the epithelium. During my post-doctoral training, we identified this PMN chemo-attractant as the eicosanoid, hepoxilin A3 (HXA3). This proposal delineates a focused approach to identify enzymes responsible for HXA3 synthesis in the infected lung epithelium. Specifically, phospholipase A2s (PLA2) and 12-lipoxygenases (12-LOs) will be analyzed. PLA2 enzymes are primarily responsible for generation arachidonic acid, which is the precursor of all eicosanoids and 12-LO mediates the conversion of arachidonic acid into HXA3. Both lung epithelial cells and pathogenic bacteria possess PLA2 activity and we will investigate the contribution of each source of PLA2 towards the production of HXA3 in this proposal. Future studies will evaluate to role of HXA3 using more complex and/or more disease relevant models such as air-liquid interface cultures, CFTR mutant epithelial cells, co-cultures with epithelial-endothelial monolayers, whole tissue, and whole animal. Also, an important future consideration involves the analysis of tissues from patients with mucosal inflammatory conditions to determine if an increased expression of enzymes critical for HXA3 production is observed. A thorough understanding of this unexplored pathway will lead to strategies that selectively block HXA3 production. My long-term career goal is to develop therapeutics that alleviates destructive inflammation at mucosal surfaces. Diseases that may benefit from this therapeutic strategy are not exclusive to the lung. Infections of the skin, urogenital tract, and gut, as well as idiopathic conditions such as psoriasis and inflammatory bowel disease all share destructive PMN infiltration at the epithelial surface and may involve dys-regulation of HXA3 production. These studies could ultimately result in the development of an entirely new series of anti-inflammatory drugs having efficacy towards a wide range of pathologies