Eur Respir J. 2020 Oct 8:2002708. doi: 10.1183/13993003.02708-2020. Online ahead of print.
Cellular senescence permanently arrests the replication of various cell types and contributes to age-associated diseases. In particular, cellular senescence may enhance chronic lung diseases including chronic obstructive pulmonary disease and idiopathic pulmonary fibrosis. However, the role cellular senescence plays in the pathophysiology of acute inflammatory diseases, especially viral infections, is less well-understood. There is evidence that cellular senescence prevents viral replication by increasing antiviral cytokines, but other evidence shows that senescence may enhance viral replication by downregulating antiviral signalling. Furthermore, cellular senescence leads to the secretion of inflammatory mediators, which may either promote host defense or exacerbate immune pathology during viral infections. In this perspective, we summarise how senescence contributes to physiology and disease, the role of senescence in chronic lung diseases, and how senescence impacts acute respiratory viral infections. Finally, we develop a potential framework of how senescence may contribute, both positively and negatively, to the pathophysiology of viral respiratory infections, including SARS-CoV-2.