SUMMARY: OVERALL PROGRAM The goal of this Program Project Grant (PPG) is advancing the latest discoveries in stem cell biology, human organoid models, and gene editing to understand and treat genetic lung diseases. After a century of basic sciences advances, culminating in recent Nobel Prize-winning discoveries, such as nuclear reprogramming and gene editing, biomedical research now faces an inflection point, poised for clinical translation of basic science successes. While it is hard to envision a more optimistic time in health-related research, treatments for many devastating lung diseases have not yet been realized, and clinical therapies in most cases still largely focus on treating symptoms or maintaining life support to allow endogenous lung tissue stem cells enough time to repair, without available therapies able to interrupt disease-initiating mechanisms or augment the lung’s capacity to regenerate. Here we address these challenges by proposing an integrated, multi-investigator PPG to translate lung stem cell research from basic discovery to future clinical applications. An initial focus on ameliorating genetic lung diseases of the airway and alveoli is pursued, given that their proximal disease-driving gene mutations are well described. The use induced pluripotent stem cells (iPSCs) carrying these mutations or their gene-edited progeny is a shared technology harnessed by all Projects together with a proposed Gene Editing Core, and coordinated by an Administrative Core. Our 4 project leaders have worked together extensively to develop protocols to differentiate iPSCs into a broad diversity of lung epithelial lineages, recently optimizing methods to produce the two stem cell populations that maintain all airway and alveolar epithelia, basal cells and alveolar type 2 cells (AT2s), respectively. Having established these stem cell banks and protocols, we turn our focus here on applying these resources to advance our mechanistic understanding of how gene mutations initiate airway and alveolar epithelial dysfunction resulting in disease, and we seek to therapeutically intervene with novel precision therapeutics or regenerative cell therapies. Towards these goals, we here propose 4 projects and 2 cores, all interacting to complete shared aims, and synergistic cross-project experiments. Aim 1 will promote collaborative, integrated cross-project approaches that produce new human models of genetic airway and alveolar diseases, and will apply these in vitro iPSC and organoid-based models to understand basic pathogenic mechanisms that lead from epithelial dysfunction to lung disease. Aim 2 will identify potential therapeutic strategies able to reverse or ameliorate aberrant pathways responsible for the alveolar dysfunction present in genetic diseases that affect the distal lung, including proteostasis, mitochondrial dysfunction, and metabolic changes that we hypothesize lead to reversible epithelial toxic gain-of-function phenotypes. Aim 3 will devel...