Stem Cells Sheltered from Air-Raids Repair Airways

The studies by Tata et al. and Lynch et al. in 2018 demonstrated that myoepithelial cells (MECs) in submucosal glands (SMGs) of the respiratory tract could act as reserve stem cells to regenerate the surface airway epithelium (SAE) after severe injury. Using lineage tracing and marker analysis, they showed that MECs proliferated, migrated, and differentiated into SAE cells, driven by Wnt/Lef-1 and Sox9 signaling pathways. This regenerative response was significant under severe injury conditions but not under mild injury or homeostasis. The findings highlighted the potential of MECs in airway repair and raised new questions about the mechanisms and environmental factors influencing this process.