D15-01 Patient-derived Airway Organoids Model Therapy Responses in Neonatal Bronchopulmonary Dysplasia

Rationale Modeling BPD is limited by scarce neonatal lung tissue, despite the physiologic relevance of 3D airway organoids. Bronchoalveolar lavage (BAL) from intubated preterm infants provides a clinically accessible source of airway epithelium. We derived BAL-based airway organoids (BAL-AOs) to capture patient-specific epithelial diversity and drug responses. We hypothesized that BAL-AOs retain disease-relevant epithelial states of BPD and will reproduce patient-specific injury-repair phenotypes and therapeutic responses ex vivo. Methods BAL-AOs were generated from BAL samples (Liu et al.) of 7 BPD patients (4 male, 3 female). Organoid formation and cellular composition were assessed via microscopy, immunofluorescence, and single-cell RNA sequencing (Fig 1A). We subjected male and female BAL-derived airway organoids exposed to dexamethasone (250 ng/ml) or vehicle to bulk RNA sequencing. Findings were validated against LungMAP human BPD lung specimens (control, evolving, chronic, healed). The role of sex as a biological variable was also assessed in response to dexamethasone. Results BAL-AOs demonstrated cellular heterogeneity in human airways and exhibited robust differentiation into basal, ciliated, and secretory cell types (Fig. 1B). The majority of the differentially expressed genes (DEGs) in male (88 up, 132 down) and female (90 up, 112 down) organoids were unique to each sex, with 26.3 % genes common between the male and female organoids (Fig 1C). Pathway analysis after exposure to dexamethasone showed downregulation of inflammatory and remodeling pathways, including NF-κB and chemokine signaling. Female organoids showed strong enrichment of cell cycle (E2F targets, DNA replication), while male organoids showed negative enrichment for epithelial proliferation. Female organoids uniquely showed enrichment of surfactant-associated pathways, suggesting that dexamethasone triggered expression of surfactant proteins (like SFTPB) and related alveolar maturation genes predominantly in females (Fig 1D). DEGs were validated with the LungMAP data. Conclusion BAL-AOs offer a novel, patient-specific platform for modeling neonatal BPD, enabling mechanistic insights into therapeutic response. Together with complementary models such as iPSC organoids, lung-on-a-chip devices, and animal studies, BAL-derived organoids will be a powerful tool for testing novel interventions. This abstract is funded by: NIH