A robust human airway organoid platform enables scalable expansion and trajectory mapping of pulmonary neuroendocrine cells

Pulmonary neuroendocrine cells (PNECs) are rare chemosensory epithelial cells, facultative stem cells, and a cell-of-origin for neuroendocrine lung cancers, yet the mechanisms governing their differentiation and heterogeneity are poorly understood. Here we establish NEr-fAOs, a human fetal airway organoid platform that robustly enriches PNECs, and identify a cooperative requirement for dual GSK3 and NOTCH inhibition to drive directed PNEC differentiation. This strategy yields stable cultures with up to 60-fold expansion of PNECs whose transcriptomes closely match fetal and adult PNECs. In addition to PNEC-enrichment, NEr-fAOs retain diverse airway epithelial cell types, preserving epithelial complexity. Time-resolved single-cell transcriptomics maps PNEC trajectories in NEr-fAOs, resolving precursor and mature states. Comparative analyses further reveal a distal airway bias in NEr-fAOs and enrichment for lower-airway progenitors. NEr-fAOs thus provide a scalable, tractable platform to dissect human PNEC biology and distal airway progenitor hierarchies relevant to lung development, cancer, and disease.