Human iPSC-Based Alveolus-on-Chip Reveals Immunometabolic Regulation of Influenza A Virus Infection by Butyrate

Influenza A virus (IAV) infection was modelled in this system to test the influence of the short-chain fatty acid butyrate on viral replication. Single-cell RNA sequencing and cytokine profiling were used to map transcriptional dynamics and immune–metabolic responses related to viral infection and butyrate treatment. The alveolus-on-chip recapitulated key features of the human distal lung, including epithelial–macrophage crosstalk, barrier integrity, and IAV susceptibility.

Macrophage plasticity and epithelial remodeling were central determinants of infection outcome. Butyrate treatment constrained host biosynthetic and metabolic programs exploited by IAV, including ribosome biogenesis, RNA processing, and mitochondrial function, while preserving type I/II interferon signaling. Cytokine profiling further demonstrated reduced IL-1β and TNF-α, elevated IL-10, and increased GM-CSF, suggesting a shift toward regulatory and tissue-supportive immunity.

This study establishes an isogenic iPSC-derived alveolus-on-chip as a human-relevant platform to dissect immunometabolic regulation during viral infection. The model reveals a dual role of butyrate in dampening inflammation and metabolic activation while maintaining antiviral defense. Beyond influenza, the approach may serve as a scalable framework for patient-specific modeling of respiratory infections and for assessing nutritional or metabolite-based interventions.