Fibrinolytic niche is requested for alveolar type 2 cell-mediated alveologenesis and injury repair
Ali, G.; Zhao, R.; Zhang, M.; Jain, K. G.; Chang, J.; Komatsu, S.; Fang, X.; Zhou, B.; Liang, J.; Jiang, D.; Ikebe, M.; Matthay, M. A.; Ji, H.-L.
Show abstract
COVID-19, SARS, and MERS are featured by fibrinolytic dysfunction. To test the role of the fibrinolytic niche in the regeneration of alveolar epithelium, we compared the self-renewing capacity of alveolar epithelial type 2 (AT2) cells and its differentiation to AT1 cells between wild type (wt) and fibrinolytic niche deficient mice (Plau-/- and Serpine1Tg). A significant reduction in both proliferation and differentiation of deficient AT2 cells was observed in vivo and in 3D organoid cultures. This decrease was mainly restored by uPA derived A6 peptide, a binding fragment to CD44 receptors. The proliferative and differential rate of CD44+ AT2 cells was greater than that of CD44- controls. There was a reduction in transepithelial ion transport in deficient monolayers compared to wt cells. Moreover, we found a marked suppression in total AT2 cells and CD44+ subpopulation in lungs from brain dead patients with acute respiratory distress syndrome (ARDS) and a mouse model infected by influenza viruses. Thus, we demonstrate that the fibrinolytic niche can regulate AT2-mediated homeostasis and regeneration via a novel uPA-A6-CD44+-ENaC cascade.
Matching journals
The top 10 journals account for 50% of the predicted probability mass.