Abstract
Post-acute sequelae of SARS-CoV-2 (PASC) occurs in subsets of individuals, including those with preexisting lung disease. To investigate PASC pathogenesis and therapeutics in a chronic bronchitis mouse model (Scnn1b-Tg), Scnn1b-Tg and WT mice were inoculated with a mouse-adapted SARS-CoV-2 virus (SARS-CoV-2 MA10) and followed for 60 days. Viral titer, histology, immunohistochemistry, single-cell RNA sequencing, RNA in situ hybridization, and spatial transcriptomic profiling characterized disease pathologies. Scnn1b-Tg mice inoculated with SARS-CoV-2 MA10 exhibited lower viral titers and less weight loss than WT mice. Airway epithelia of Scnn1b-Tg mice were less infected than epithelia of WT mice, reflecting increased airway mucus and enhanced epithelial antiviral activities in Scnn1b-Tg mice. However, Scnn1b-Tg mice subsequently exhibited heterogeneous airway and parenchymal disease with elevated Il33 expression characteristic of human eosinophilic pneumonia. Cohorts of infected mice were given a monoclonal antibody targeting the IL-33 receptor (ST2) or enteral prednisone. Administration of an anti-ST2 monoclonal antibody mitigated development of eosinophilic pneumonia, while enteral prednisone suppressed IL-33 expression and disease. The eosinophilic pneumonia in Scnn1b-Tg mice after SARS-CoV-2 MA10 infection mimics reports of eosinophilic pneumonia in humans after SARS-CoV-2, suggesting that targeting of IL-33 may be beneficial in treating post-viral eosinophilic pneumonia in humans.
Authors
Padraig E. Hawkins, Sarah R. Leist, Hong Dang, Minako Saito, Lisa C. Morton, Jesse B. Hines, Rodney C. Gilmore, Stephen A. Schworer, Ella F. Burns, Jason R. Rock, Robert S. Hagan, James J. Pestka, Alexandra Schäfer, Kenichi Okuda, Lauren K. Heine, Jack R. Harkema, Wanda K. O’Neal, Alessandra Livraghi-Butrico, Raymond J. Pickles, Ralph S. Baric, Richard C. Boucher
Figure 6
Transcriptional analysis reveals activated AT2 cells and Th2-skewed macrophages at baseline.
