Abstract Rationale Alveolar regeneration after acute lung injury or surgical resection is essential for restoring lung function, yet no effective therapy exists. Mesenchymal cells, particularly alveolar myofibroblast (AMF)-like cells, re-engage developmental programs during repair, but their precise role and therapeutic potential remain unclear. Methods We developed an intersectional genetic approach to selectively label and ablate AMF-like cells during regeneration following influenza A virus (PR8) injury or compensatory regrowth after pneumonectomy. Longitudinal analyses included histology, stereology, spatial transcriptomics and scRNA-seq of lineage-labeled cells. Candidate pathways were validated in alveolar organoids and tested in human alveolosphere cultures using donor and COPD lung tissues. Results Targeted manipulation of AMF-like cells revealed their critical involvement in alveolar repair and regrowth. Transcriptomic profiling uncovered conserved epithelial-mesenchymal communication networks across distinct injury contexts. Functional assays in organoid systems demonstrated the importance of these niche-stem cell interactions for alveolar morphogenesis. In human lung tissue, corresponding mesenchymal signatures were detected and evaluated in disease settings, and preliminary ex vivo studies supported the feasibility of modulating these pathways to enhance regenerative capacity. Conclusions AMF-like cells are indispensable for alveolar repair. Intersectional genetics combined with organoid and human validation uncovers actionable epithelial-mesenchymal circuits, offering a translational framework to restore regeneration and prevent fibrosis. Clinical relevance Targeting AMF-like cell pathways could enable regenerative therapies for influenza sequelae, post-resection recovery, and COPD/emphysema. This abstract is funded by: German Research Foundation (DFG)
Khadim et al. (Fri,) studied this question.