Proteomics and phosphoproteomics of SARS-CoV-2 and IAV treated APCs

The clinical course of SARS-CoV-2 infection is highly variable with a subset of patients developing severe COVID-19 and acute respiratory distress syndrome (ARDS). COVID-19 induced lung injury and respiratory failure appears to be driven by dysregulated immune responses, yet the exact mechanisms remain unknown. Here, we analyzed monocytes isolated from healthy donors treated with SARS-CoV-2, influenza A (Panama strain) or TLR7/8 agonist R848. Notably, overnight exposure to SARS-CoV-2, but not influenza A virus, induced a profibrotic signature, characterized by high expression of known fibrogenic factors like TGFB1, SPP1 and LGMN, and showed highly significant similarity with profibrotic macrophage populations identified in idiopathic pulmonary fibrosis (IPF). In conclusion, SARS-CoV-2 triggers profibrotic macrophage responses, and ARDS-associated lung fibrosis.