TRACHEAL SECRETORY FUNCTION DURING DEVELOPMENT & FOLLOWING INJURY

儿童早期肺部感染可导致以后的呼吸道功能障碍 在生活中。高分子量呼吸道上皮细胞的高分泌 糖共轭化合物(HMG)，包括粘蛋白和蛋白多糖，可能发挥一种 在这些个体的呼吸道病理生理学中也起着重要作用 作为患有支气管肺发育不良、哮喘和囊性纤维化的儿童。 拟议研究的目标是阐明分子和 气管表面上皮细胞分泌功能的细胞变化 在发育过程中和受伤后。发育中的气管表面 生后雪貂的上皮细胞将是我们的实验模型。我们建议 以确定分泌细胞群体的发育模式 用阿尔新蓝-高碘酸席夫氏染色鉴定细胞 2)使用单抗进行免疫细胞化学 特异性识别粘蛋白和蛋白多糖表位的抗体 鉴定分泌细胞群和3)原位杂交 用于检测产生粘蛋白的细胞的粘蛋白多肽cDNA探针，有或没有 分泌颗粒。此外，我们建议验证HMG的分泌物 表面上皮细胞对离子霉素和人中性粒细胞弹性蛋白酶的反应 用免疫测定法测定HMG释放到培养上清液中 分泌细胞脱颗粒的可视化和定量研究 视频显微镜检查。我们还将评估增长因素在以下方面的作用 分泌细胞分化和功能的调节因子 开发和修复。雪貂气管短期损伤后 含二氧化硫或硝酸蒸气的上皮细胞改变 将评估分泌细胞的数量和功能。我们期待着 修复过程将至少部分概括正常发育 事件。然而，严重的伤害可能会导致背离秩序 再上皮化，导致分泌细胞数量增加和 分泌率增加，可能是由于细胞对 分泌激动剂。拟议的研究应该提供重要的 关于成熟呼吸道分泌HMG的信息和有用的 对高分泌状态的发病机制的洞察 受伤。

Lung infections in early childhood can result in airways dysfunction later in life. Hypersecretion by airways epithelium of high molecular weight glycoconjugates (HMG), including mucins and proteoglycans, may play an important role in pathophysiology of airways in these individuals as well as children with bronchopulmonary dysplasia, asthma, and cystic fibrosis. The objective of the proposed studies is to elucidate molecular and cellular changes in the secretory functions of tracheal surface epithelium during development and following injury. The developing tracheal surface epithelium of postnatal ferrets will be our experimental model. We propose to identify developmental patterns of secretory cell populations by employing 1) Alcian blue-periodic acid Schiff's staining to identify cells that store glycoconjugates, 2) immunocytochemistry using monoclonal antibodies that specifically recognize mucin and proteoglycan epitopes to identify secretory cell populations and 3) in situ hybridization using mucin peptide cDNA probes to detect mucin producing cells, with or without secretory granules. In addition, we propose to verify the HMG secretory responses of surface epithelium to ionomycin and human neutrophil elastase by immunoassay of HMG released into culture medium and by direct visualization and quantitation of secretory cell degranulation using videomicroscopy. We will also assess the role of growth factors as modulators of secretory cell differentiation and function during development and repair. Following short term injury to ferret tracheal epithelium with sulfur dioxide or nitric acid vapor, alteration of secretory cell populations and function will be assessed. We expect the repair process will, at least in part, recapitulate normal developmental events. However, severe injury may result in departure from orderly reepithelialization, resulting in increased secretory cell numbers and increased secretory rates, perhaps due to augmented sensitivity of cells to secretory agonists. The proposed studies should provide important information concerning HMG secretion in maturing airways and useful insights into the pathogenesis of hypersecretory states resulting from injury.