Therapeutic strategies to favor epithelial repair and regeneration in preclinical models of primary airway and alveolar cultures and live lung tissue

Bacterial infections with <italic>S. aureus</italic> (SA) and <italic>P. aeruginosa</italic> (PA) are responsible for epithelial damage and play a role in the development/progression of acute and chronic lung diseases. Bacterial virulence factors (VirF) also alter epithelial repair. Proreparative strategies are thus needed to restore lung integrity and function. Importantly, our previous work has revealed a prorepair role of K⁺ channels. Our aims were to 1) implement preclinical models and cutting edge protocols to study airway and alveolar repair/regeneration, 2) assess the effect of PA and SA VirF on epithelial repair/regeneration, and 3) demonstrate K⁺ channel activator benefit despite infection. Human airway and alveolar primary cell cultures were used to study early steps (i.e. guided cell migration, cell proliferation, repair rates) and late stage of epithelial repair/regeneration (restoration of a tight and fully differentiated epithelium). Tissue integrity was also evaluated within serial slices of living lung tissue (with the innovative protocol of precision cut lung slices, PCLS). Cultures and PCLS were exposed to PA or SA VirF and K⁺ channel (K_ATP, KvLQT1) activators. Our data showed that PA and SA VirF severely altered early and late repair steps in airway and alveolar cell cultures from healthy donors and patients with respiratory diseases. This deleterious effect was reversed by K⁺ channel activators, which also enhanced ciliogenesis during airway regeneration and markers of functional integrity in PCLS. Our findings highlight pro-reparative/-regenerative effects of K⁺ channel activators, despite the presence of infection, in innovate pre-clinical models.