A novel in vitro model of primary human pediatric lung epithelial cells

Current in vitro human lung epithelial cell models derived from adult tissues may not accurately represent all attributes that define homeostatic and disease mechanisms relevant to the pediatric lung. We report methods for growing and differentiating primary Pediatric Human Lung Epithelial (PHLE) cells from organ donor infant lung tissues. We use immunohistochemistry, flow cytometry, quantitative RT-PCR, and single cell RNA sequencing (scRNAseq) analysis to characterize the cellular and transcriptional heterogeneity of PHLE cells. PHLE cells can be expanded in culture up to passage 6, with a doubling time of ~4 days, and retain attributes of highly enriched epithelial cells. PHLE cells can form resistant monolayers, and undergo differentiation when placed at air-liquid interface. When grown at Air-Liquid Interface (ALI), PHLE cells expressed markers of airway epithelial cell lineages. scRNAseq suggests the cultures contained 4 main sub-phenotypes defined by expression of FOXJ1, KRT5, MUC5B, and SFTPB. These cells are available to the research community through the Developing Lung Molecular Atlas Program Human Tissue Core. Our data demonstrate that PHLE cells provide a novel in vitro human cell model that represents the pediatric airway epithelium, which can be used to study perinatal developmental and pediatric disease mechanisms.