PT - JOURNAL ARTICLE AU - Stefanie Deinhardt-Emmer AU - Sarah Böttcher AU - Clio Häring AU - Liane Giebeler AU - Andreas Henke AU - Roland Zell AU - Franziska Hornung AU - Christian Brandt AU - Mike Marquet AU - Alexander S. Mosig AU - Mathias W. Pletz AU - Michael Schacke AU - Jürgen Rödel AU - Regine Heller AU - Sandor Nietzsche AU - Bettina Löffler AU - Christina Ehrhardt TI - SARS-CoV-2 causes severe alveolar inflammation and barrier dysfunction AID - 10.1101/2020.08.31.276725 DP - 2020 Jan 01 TA - bioRxiv PG - 2020.08.31.276725 4099 - http://biorxiv.org/content/early/2020/09/02/2020.08.31.276725.short 4100 - http://biorxiv.org/content/early/2020/09/02/2020.08.31.276725.full AB - Infections with SARS-CoV-2 lead to mild to severe coronavirus disease-19 (COVID-19) with systemic symptoms. Although the viral infection originates in the respiratory system, it is unclear how the virus can overcome the alveolar barrier, which is observed in severe COVID-19 disease courses.To elucidate the viral effects on the barrier integrity and immune reactions, we used mono-cell culture systems and a complex human alveolus-on-a-chip model composed of epithelial, endothelial, and mononuclear cells.Our data show that SARS-CoV-2 efficiently infected epithelial cells with high viral loads and inflammatory response, including the interferon expression. By contrast, the adjacent endothelial layer was no infected and did neither show productive virus replication or interferon release. With prolonged infection, both cell types are damaged, and the barrier function is deteriorated, allowing the viral particles to overbear.In our study, we demonstrate that although SARS-CoV-2 is dependent on the epithelium for efficient replication, the neighboring endothelial cells are affected, e.g., by the epithelial cytokine release, which results in the damage of the alveolar barrier function and viral dissemination.