A Biofabricated Human Acinus-on-a-Chip Unveils Mechanotransductive Drivers of Ventilator-Induced Lung Injury via Decoupling Volutrauma and Barotrauma.

Ventilator-induced lung injury (VILI), an iatrogenic complication of mechanical ventilation, remains poorly understood due to the absence of physiologically relevant in vitro models, impeding targeted therapy development. Here, we engineer a bioinspired acinus-on-a-chip model recapitulating human pulmonary acinar architecture and VILI pathological hallmarks, enabling mechanistic elucidation by decoupling distinct mechanical injury modes. Crucially, we uncover fundamentally divergent molecular pathways that volutrauma predominantly drives DNA damage response (DDR)-mediated P53-dependent apoptosis and nuclear factor kappa-B (NF-κB)-driven inflammation, whereas barotrauma primarily triggers mitochondrial dysregulation, Wnt suppression, and metabolic collapse. Single-cell profiling further reveals injury mode-specific heterogeneity, identifying a rare TGF-β-enriched basal-secretory transitional cluster in barotrauma that possibly drives fibrotic remodeling. Pharmacological P21 inhibition, agonist-mediated Wnt pathway activation, or pathological mitochondrial fragmentation inhibition each significantly ameliorated VILI severity, with findings correlating strongly with clinical outcomes. Collectively, this study establishes a mechanobiological framework to optimize ventilation and reveals novel VILI therapeutics by integrating microengineering with stem cell biology.