Lung epithelial cell specification in human pluripotent stem cells

肺移植仍然是终末期肺病的唯一确定性治疗方法 由于严重的并发症和捐献器官的短缺而受阻。一个潜在 对于至少某些上皮受到特异性影响的疾病， 细胞或细胞替代疗法。这种疗法的应用还很遥远， 然而.细胞治疗的先决条件是无限量供应正确的上皮细胞， 祖细胞和有效的植入程序。在本建议中，我们主要关注 第一个目标，并使用通用损伤模型来证明这些细胞的潜力。 为了解决潜在气道祖细胞无限供应的问题，我们将重点放在 胚胎干细胞（ESC）和诱导多能干细胞（iPSC）， 称为人多能干细胞（hPSC）。我们在这里描述的一代从 可以将推定的胎肺远端尖端祖细胞（pDTP）群体的hPSC 不断扩大（到现在18个月），并有效地重新填充大部分或全部 免疫缺陷NSG小鼠的博来霉素损伤的肺中的谱系。而且这些 细胞可以转化为具有基底细胞（BC）的所有特征的细胞，即干细胞。 然而，气道的细胞显示出更有限的扩张。尽管事实上 将pDTP移植到博来霉素处理的NSG小鼠的气道中，衍生的BC样细胞 没有移植，这表明BC可能不具备移植能力，或者 博来霉素不是这些细胞的合适损伤模型。本提案的目的是 分子表征这两种细胞群，并评估它们在各种 伤害模型该提案的具体目标是： 目的1：pDTP和BC样细胞的分子和体外表征 目标二。hPSC衍生的pDTP和BC样细胞的体内潜力。 目标3：pDTP的培养条件和克隆性。

Lung transplantation, the only definitive treatment for end-stage lung disease, remains hampered by severe complications and a shortage of donor organs. One potential alternative for at least some diseases where the epithelium is specifically affected is stem cell or cellular replacement therapy. Application of this type of therapy is still far away, however. Prerequisites for cellular therapy are an unlimited supply of the correct epithelial progenitors and an efficient engraftment procedure. In this proposal, we focus primarily on the first goal, and use generic injury models to demonstrate the potential of these cells. To address the issue of an unlimited supply of potential airway progenitors, we focused on embryonic stem cells (ESCs) and induced pluripotent stem cells (iPSCs), collectively termed human pluripotent stem cells (hPSCs). We describe here the generation from hPSCs of a population of putative fetal lung distal tip progenitors (pDTPs) that can be expanded continuously (up to now 18 months) and efficiently repopulates most or all lineages in bleomycin-injured lungs of immunodeficient NSG mice. Furthermore, these cells can be converted to cells with all the characteristics of basal cells (BCs), the stem cells of the airway, which, however, showed more limited expansion. Despite the fact the pDTPs engrafted in the airways of bleomycin-treated NSG mice, the derived BC-like cells did not engraft, suggesting that BCs may not possess engraftment capacity or that bleomycin is not an appropriate injury model for these cells. The goal of this proposal is to molecularly characterize both cell populations and evaluate their potentials in a variety of injury models. The specific aims of the proposal are: Aim 1: Molecular and in vitro characterization of pDTPs and BC-like cells Aim 2. In vivo potential of hPSC-derived pDTPs and BC-like cells. Aim 3. Culture conditions and clonality of pDTPs.