Single‐cell RNA sequencing of peripheral blood mononuclear cells from bronchopulmonary dysplasia

Abstract

Abstract Background Bronchopulmonary dysplasia (BPD) is a severe respiratory disease that primarily affects premature infants, characterized by persistent inflammation and abnormal immune activation. This study aimed to elucidate the immunological mechanisms underlying BPD by integrating single‐cell RNA sequencing with T/B cell receptor profiling of peripheral blood mononuclear cells (PBMCs) from preterm infants with BPD, complemented by validation in a murine BPD model. Methods We profiled PBMCs from preterm infants diagnosed with BPD and healthy controls, identifying 22 distinct cell clusters corresponding to major immune cell types. Results Significant alterations were observed in myeloid and lymphoid subsets, with neutrophils undergoing metabolic reprogramming toward oxidative phosphorylation. T and B cell subsets exhibited phenotypic and functional changes, with B cells serving as crucial interaction hubs in cell communication networks. Progenitor cell analysis in BPD mouse models revealed specific alterations in hematopoietic stem cells. Analysis of cell–cell communication networks highlighted intricate intercellular interactions in BPD, emphasizing a pivotal role for the BTLA‐TNFRSF14 signaling axis in disease pathogenesis. Additionally, pharmacological blockade of BTLA in mouse models alleviated disease severity, suggesting its potential therapeutic effects through modulation of the BTLA‐TNFRSF14 pathway. Conclusion These findings enhance the understanding of the BPD immune microenvironment and lay the foundation for developing targeted immunomodulatory therapies. Highlights Single‐cell sequencing revealed immune cell profiles in bronchopulmonary dysplasia (BPD). Neutrophils underwent metabolic changes, and B cells were key in immune communication. Targeting B and T lymphocyte attenuator (BTLA)‐TNFRSF14 signalling reduced BPD severity in mouse models, suggesting a potential therapy.