Batf2 knockdown ameliorates early-stage hyperoxia-induced BPD-like lung injury and is associated with suppression of GBP5/NF-κB signaling

OBJECTIVE: Bronchopulmonary dysplasia (BPD) is characterized by persistent inflammation and impaired alveolar development. Macrophage inflammatory dysregulation contributes to BPD progression, but its upstream regulators remain incompletely understood. This study investigated the role of Batf2 in hyperoxia-induced lung injury and its potential association with GBP5/NF-κB signaling. METHODS: Batf2 was initially screened using the peripheral blood transcriptomic dataset GSE32472. An early-stage hyperoxia-induced BPD-like lung injury model in neonatal mice and an LPS-stimulated RAW264.7 inflammatory macrophage model were used for in vivo and in vitro validation, respectively. Macrophages were depleted using clodronate liposomes, and Batf2 was silenced using adenoviral shRNA in vivo and siRNA in vitro. Alveolar development and macrophage polarization-related changes were evaluated by histological staining, radial alveolar count, western blotting, RT-qPCR, immunofluorescence staining, and flow cytometry. RNA sequencing, GBP5 knockdown, and GBP5 overexpression rescue experiments were performed to investigate downstream mechanisms. RESULTS: Batf2 expression was increased in BPD-related peripheral blood transcriptomic data, hyperoxia-exposed neonatal lungs, and LPS-stimulated RAW264.7 macrophages. Hyperoxia induced alveolar simplification and a pro-inflammatory macrophage-associated phenotype, whereas macrophage depletion attenuated lung injury. Batf2 knockdown improved alveolar development, reduced M1-associated and pro-inflammatory markers, and restored M2-associated markers. RNA sequencing identified Gbp5 as a Batf2-associated candidate gene. GBP5 overexpression partially reversed the changes in iNOS and Arg1 induced by Batf2 silencing, whereas GBP5 knockdown reduced inflammatory mediators and suppressed NF-κB p65 phosphorylation and nuclear translocation. In hyperoxia-exposed lung tissues, Batf2 knockdown was also associated with reduced GBP5 expression and p65 phosphorylation. CONCLUSION: Batf2 knockdown alleviates early BPD-like alveolar injury and macrophage-associated inflammatory responses in hyperoxia-exposed neonatal mice. GBP5/NF-κB signaling may partially contribute to Batf2-associated inflammatory regulation, although the cellular and molecular causality of this pathway requires further validation.