MECHANISMS OF PULMONARY EPITHELIAL CELL DIFFERENTIATION

肺上皮细胞的生长和分化至关重要 肺功能的决定因素。这些相同的过程，或者作为一种反应， 肺损伤，肿瘤转化，或内在的异常， 生长和分化，是发病的重要因素， 人类肺部疾病 此外，对生物学的理解 肺上皮细胞的生长和分化对于 实现基因治疗在肺部的全部潜力。 长期 这些研究的目的是确定分子和细胞 调节近端肺组织生长和分化的机制 上皮对中华绒螯蟹生长和分化机制的研究 发展肺将导致重要的见解的作用，这些 过程在肺部疾病中发挥作用。 这项建议的具体目标是 旨在检查发育中细胞的谱系关系， 气道上皮及其分化调控的分子机制 在这个上皮细胞中。这些研究将利用独特的转基因技术 原始近端和远端肺上皮的标记物，以检查 在早期肺发育过程中细胞向不同谱系的分配 发展肺间质在调节这些方面的作用 早期发育决定将通过以下方法在胎肺中进行检查： 破坏正常的间充质上皮相互作用。 额外 深入了解发育中细胞的谱系关系， 肺上皮和Clara细胞作为祖细胞的作用将 通过对表达Clara细胞分泌的细胞进行致突变性消融来获得 蛋白质-HSV胸苷激酶转基因发育过程中。 最后， 近端肺动脉中潜在的分化介质 将通过以下技术鉴定和表征上皮： 差减杂交荧光激活细胞分选将是 用于获得原始近端和原始远端的种群 表达β-半乳糖苷酶转基因的肺上皮细胞。 在构建近端和远端上皮cDNA后， 文库中，将进行消减杂交以分离和 表征来自原始近端肺动脉的独特克隆 上皮

Growth and differentiation of the pulmonary epithelium are essential determinants of lung function. These same processes, either as a response to lung injury, neoplastic transformation, or intrinsic abnormalities of growth and differentiation, are important factors in the pathogenesis of human lung disease. Additionally, an understanding of the biology of growth and differentiation of the pulmonary epithelium is essential for realizing the full potential of gene therapy in the lung. The long term objective of these studies is to define the molecular and cellular mechanisms regulating growth and differentiation in the proximal pulmonary epithelium. A study of the mechanisms of growth and differentiation in the developing lung will lead to important insights into the role these processes play in lung disease. The specific aims in this proposal are intended to examine the lineage relationships of cells in the developing airway epithelium and the molecular mechanisms regulating differentiation within this epithelium. These studies will utilize unique transgenic markers of primitive proximal and distal pulmonary epithelium to examine the allocation of cells to different lineages during early lung development. The role of the pulmonary mesenchyme in regulating these early developmental decisions will be examined in explanted fetal lungs by disruption of normal mesenchymal epithelial interactions. Additional insights into the lineage relationships of cells in the developing pulmonary epithelium and the role of Clara cells as progenitor cells will be gained by toxigenic ablation of cells expressing a Clara cell secretory protein-HSV thymidine kinase transgene during development. Finally, potential mediators of differentiation in the proximal pulmonary epithelium will be identified and characterized by the technique of subtractive hybridization. Fluorescence activated cell sorting will be used to obtain populations of primitive proximal and primitive distal pulmonary epithelial cells expressing a beta-galactosidase transgene. Following the construction of proximal and distal epithelial cDNA libraries, subtractive hybridization will be performed to isolate and characterize unique clones from the primitive proximal pulmonary epithelium.