Alveolar Repair after Viral Injury: A Tale of Two Cell Types

Kass-Gergi and Vaughan discuss how alveolar repairs after viral injury. Sendai virus (SeV) is a murine paramyxovirus that bears significant homology to human parainfluenza virus 1. For years, it has been used as a vector for gene therapy in mouse models, but its antigenicity and induction of host immune responses make it an excellent natural model of injury and repair. The paper by Hernandez et al which capitalizes on these observations and use SeV infection to uncover fascinating and largely novel aspects of epithelial repair after respiratory viral injury, highlighting a previously unknown role for alveolar type 1 (AT1) cells in these processes. The authors observe a previously undescribed phenomenon of AT2-less regions in murine lungs in response to injury, begging direct comparison with mouse models of influenza and SARS-CoV-2 infection.