Chymotrypsin-like Elastase 1 in Lung Development and Disease

项目摘要 正常的出生后肺形态发生和损伤后的修复需要精确的协调， 细胞活性和基质重塑的形成或恢复正常的肺泡 结构和最佳的呼吸效率。我们最近发现了蛋白酶的一个关键作用， 糜蛋白酶样弹性蛋白酶1（Cela 1）在生后肺弹性调节中的作用及其意义 在α1-抗胰蛋白酶（AAT）缺乏症发病机制中的作用。这项研究计划是基于 我们的新的初步发现，Cela 1表达诱导再生过程中， 和病理性肺泡重塑，抑制Cela 1活性可防止AAT 缺乏相关的肺气肿。该提案将确定Cela 1在生理和病理中的作用。 以及出生后肺部的病理性重塑。根据数据，Cela 1表达是 由于Cela 1在高氧肺损伤中的表达失调，Aim 1将确定Cela 1在肺中的细胞特异性作用， 开发使用条件性缺失模型来鉴定Cela 1表达细胞， 表征在正常和高氧条件下发育过程中表达的动态变化 条件目的2检测病理性肺组织中Cela 1的细胞特异性表达是否发生变化 基质重塑以及靶向Cela 1是否可以长期预防肺气肿。使用 在AAT缺陷型肺气肿模型中进行谱系追踪和邻位连接原位杂交， 我们将确定Cela 1表达的ATII细胞是否代表一种独特的上皮细胞亚类， 或者是否所有ATII细胞都能在适当的环境中表达Cela 1。在目标3中，AAT是否 将测试细胞摄取所需的Cela 1中和，并且将测试参与此过程的细胞。 AAT-Cela 1复合物的吸收和再循环将使用谱系追踪、邻近性、 连接原位杂交、共聚焦显微术和流式细胞术。之间的关联 Cela 1基因表达和弹性蛋白重塑的区域将在人类AAT缺陷中被鉴定。 肺气肿标本最后，将确定Cela 1-AAT分子相互作用的位点。从 从科学和临床的角度来看，该提案将定义一种新的关键机制， Cela 1介导基质重塑过程以调节正常肺泡形成和再生 这将为探索Cela 1作为发展的靶点提供强有力的理由。 间质性肺疾病的未来疗法。

Project Summary Normal postnatal lung morphogenesis and repair after injury requires the precise coordination of cellular activities and matrix remodeling for the formation or restoration of normal alveolar structures and optimal respiratory efficiency. We recently identified a critical role for the protease, Chymotrypsin-like elastase 1 (Cela1), in the regulation of postnatal lung elastance and its critical role in the pathogenesis of α1-antitrypsin (AAT) deficiency. This program of research is based on our novel preliminary findings that Cela1 expression is induced during regenerative and pathological alveolar remodeling, and that inhibition of Cela1 activity prevents AAT deficiency related emphysema. This proposal will identify the role of Cela1 in both physiological and pathologic remodeling in the postnatal lung. Based on data that Cela1 expression is dysregulated in hyperoxic lung injury, Aim 1 will define cell-specific roles for Cela1 in lung development using conditional deletion models to identify Cela1-expressing cells and characterize dynamic changes in expression during development under normal and hyperoxic conditions. Aim 2 will test whether cell-specific expression of Cela1 changes in pathological lung matrix remodeling and whether targeting Cela1 can protect against emphysema long-term. Using lineage tracing and proximity ligation in situ hybridization in an AAT-deficient emphysema model, we will determine whether Cela1-expressing ATII cells represent a unique epithelial cell subclass or if all ATII cells can express Cela1 in the appropriate context. In Aim 3, whether AAT neutralization of Cela1 is required for cellular uptake will be tested, and the cells involved in this uptake and recycling of AAT-Cela1 complexes will be identified using lineage tracing, proximity ligation in situ hybridization, confocal microscopy, and flow cytometry. The association among Cela1 gene expression and regions of elastin remodeling will be identified in human AAT deficient emphysema specimens. Lastly, site of Cela1-AAT molecular interaction will be defined. From a scientific and clinical standpoint, this proposal will define a novel critical mechanisms by which Cela1 mediates matrix remodeling processes to regulate normal alveolarization and regeneration after injury that will provide a strong rationale to explore Cela1 as a target for development of future therapies for interstitial lung diseases.