Epithelial stem/progenitor cells as repair agents in diffuse alveolar damage

摘要 这个应用程序的总体目标是开发一个令人信服的理由和可行的方法 人上皮干/祖细胞移植治疗弥漫性肺泡损伤 终末期植入和改善器官功能。干细胞/祖细胞替代疗法被设想为一种 在以弥漫性肺泡损伤为主的几种临床情况下有意义的治疗辅助药物 上皮丢失：严重的急性肺损伤，例如由于流感或其他原因引起的ARDS，以及急性 慢性纤维性肺病的恶化。最近在应用程序中讨论的研究表明有效 肺泡再生，从而改善肺功能，需要第一阶段的扩张和迁移。 干细胞/祖细胞重建肺泡屏障，随后进行新生细胞第二阶段分化 屏障细胞分化为成熟的II型(AEC2s)和I型肺泡细胞。要为以下项目开发翻译程序 健康肺上皮干/祖细胞移植的肺泡再生：三个基本目标 提出：(1)进一步描述内源性人类远端肺的信号程序 严重创伤后上皮干细胞可以被激活，以建立新的肺泡屏障，然后 区分为AEC2。(2)人远端(小气道和肺泡)上皮池的体外发育 干细胞，既有内源性的，也有IPSC来源的，适合移植并在小鼠体内定向分化。 使用报告表面活性蛋白C和细胞角蛋白的基因编辑细胞从人iPS细胞中分离出远端基底样细胞 17(Krt17)，和Nkx2.1将用于开发移植后定向分化的可行方案。 (3)使用可通过移植获得的肺修复/再生模型作为评估 人上皮干/祖细胞的再生潜能。猕猴iPS细胞适用于 移植到感染流感的猴子身上将被用作治疗的灵长类动物模型。这是意料之中的 灵长类动物在气体交换和肺泡组织学方面的功能改善可以实现，为 干细胞/祖细胞作为严重急性肺损伤后辅助治疗的理论和方法学 在人类身上。

ABSTRACT The overall goal of this application is to develop a compelling rationale and workable methodology for the treatment of diffuse alveolar damage with transplanted human epithelial stem/progenitor cells capable of long term engraftment and improved organ function. Stem/progenitor replacement therapy is envisioned as a meaningful therapeutic adjunct in several clinical situations dominated by diffuse alveolar damage with epithelial loss: severe, acute lung injury, e.g. due to influenza or other causes of ARDS, as well as acute exacerbations of chronic fibrotic lung disease. Recent studies discussed in the application indicate effective alveolar regeneration, and thus improved lung function, requires both a first phase of expansion and migration of stem/progenitor cells to re-establish alveolar barriers followed by a second phase of differentiation of new barrier cells into mature type II (AEC2s) and type I alveolar cells. To develop a translational program for alveolar regeneration by transplantation of healthy lung epithelial stem/progenitor cells, three basic objectives are advanced: (1) Further delineation of the signaling programs by which endogenous human distal lung epithelial stem cells can be activated following major injury to establish new alveolar barriers and then differentiate to AEC2s. (2) In vitro development of pools of human distal (small airway and alveolar) epithelial stem cells, both endogenous and iPSC-derived, suitable for transplantation and directed differentiation in mice. Distal basal-like cells from human iPS cells using gene edited cells reporting surfactant protein C, cytokeratin 17 (Krt17), and NKX2.1 will be used to develop a workable protocol for directed differentiation after transplant. (3) Employ models of lung repair/regeneration approachable by transplantation as tools to assess the regenerative potential of human epithelial stem/progenitor cells. Macaque iPS cells suitable for transplantation into influenza-infected monkeys will be used as a primate model for therapy. It is anticipated that functional improvement in gas exchange and alveolar histology can be achieved in primates, providing both a rationale and methodology for stem/progenitor cells as adjunctive therapy after severe acute lung injury in humans.