Updated project metadata. Discovery of therapies that are able to correct defective CFTR requires patient derived in vitro pre-clinical cell models to be developed. Two main approaches exist to expand bronchial and nasal cultures, such as conditionally reprogrammed cells (CRC) and feeder free dual SMAD inhibition (SMADi) to overcome senescence, low cell count, and increase passages. To mimic airway epithelium the expanded cells are differentiated at air liquid Interface (ALI). This project focused to compare the global proteome of ALI differentiated CRC and SMADi expanded HNECs both treated and untreated with CFTR corrector VX-809.