Delivering antiproteases to the bronchiectatic airway

描述（由申请人提供）：上皮防御在许多化脓性气道疾病中被破坏，如原发性纤毛运动障碍和囊性纤维化。慢性气道细菌感染刺激强烈的炎症反应，导致进行性气道阻塞和支气管扩张。中性粒细胞迁移到气道中，并且一旦到达那里，在直接上皮表面的吞噬作用期间释放高浓度的中性丝氨酸蛋白酶，如中性粒细胞弹性蛋白酶。神经弹性蛋白酶和其他蛋白酶通过刺激趋化因子从呼吸道上皮释放并干扰细菌清除而使支气管扩张气道中的炎症反应持续存在。已经提出了几种策略来阻断蛋白酶的有害作用，特别是在气道中，这已经取得了有限的成功。我们已经开发了一种新的方法，允许通过多聚免疫球蛋白受体靶向呼吸道上皮，将有效的抗蛋白酶α 1-抗胰蛋白酶递送到相对不可接近的气道，该受体将药物集中在顶端表面，在那里它可能对支气管内感染和炎症产生最大的影响。在这个建议中，我们将测试的假设，气道特异性交付的α 1-抗胰蛋白酶更有效地阻止嗜酸性粒细胞衍生的丝氨酸蛋白酶在上皮细胞表面，从而提高清除细菌和减少肺部炎症反应，在良好的细胞和小鼠模型。我们计划在上皮细胞模型和在气道中特异性表达人多聚免疫球蛋白受体的小鼠中表征抗分泌成分-人α 1-抗胰蛋白酶的双功能特性。我们还将确定转染的肌肉是否可以产生和分泌“靶向”人α 1-抗胰蛋白酶，以达到持续的，循环水平的抗蛋白酶。最后，我们将建立蛋白酶抑制提供了更大的保护，对细胞外丝氨酸蛋白酶的破坏性影响，并减少细菌负荷，防止炎症反应的升级假单胞菌支气管内感染的小鼠模型。使用这种方法，我们将确定嗜中性粒细胞衍生的丝氨酸蛋白酶在气道炎症和感染的发病机制中的作用，并确定这种“靶向”抗蛋白酶是否可用于支气管扩张和其他气道疾病的治疗目的。

DESCRIPTION (provided by applicant): Epithelial defenses are breached in many, suppurative airway diseases, such as primary ciliary dyskinesia and cystic fibrosis. Chronic, airway infection with bacteria stimulates an intense, inflammatory response that leads to progressive airway obstruction and bronchiectasis. Neutrophils migrate into the airway, and once there, release high concentrations of neutral serine proteases, like neutrophil elastase, during phagocytosis at the immediate epithelial surface. Neutrophil elastase and other proteases perpetuate the inflammatory response in the bronchiectatic airway by stimulating release of chemokines from the respiratory epithelium and interfering with bacterial clearance. Several strategies have been proposed to block the deleterious effects of proteases specifically in the airway, which have had limited success. We have developed a novel approach that permits the delivery of a potent antiprotease, alpha1-antitrypsin, to relatively inaccessible airways by targeting the respiratory epithelium via the polymeric immunoglobulin receptor, which concentrates the drug at the apical surface where it potentially could have the greatest impact on endobronchial infection and inflammation. In this proposal, we will test the hypothesis that airway-specific delivery of alpha1-antitrypsin more effectively blocks neutrophil-derived serine proteases at the immediate epithelial surface, thus enhancing clearance of bacteria and reducing the pulmonary inflammatory response in well-established cell and mouse models. We plan to characterize the bifunctional properties of anti-secretory component-human alpha1-antitrypsin in epithelial cell models and mice that specifically express the human polymeric immunoglobulin receptor in the airway. We will also determine whether transfected muscle can produce and secrete "targeted" human alpha1-antitrypsin to achieve a sustained, circulating level of the antiprotease. Finally, we will establish that protease inhibition affords greater protection against the damaging effects of the extracellular serine proteases, and reduce bacterial burden and prevent the escalation of the inflammatory response in murine models of Pseudomonas endobronchial infection. Using this approach, we will define the effects of neutrophil-derived serine proteases in the pathogenesis of airway inflammation and infection, and determine whether such "targeted" antiproteases could be used for therapeutic purposes in bronchiectasis and other airway diseases.