Furthermore, monocyte-to-macrophage trajectory analysis in scRNA-seq of BALF samples from COVID-19 patients exposed enrichment of chronic hyperinflammatory monocytes in critical COVID-19 presenting with elevated expression levels of inflammasome-related genes (NLRP3, IL1-β, IL10RA) and genes associated with fibrosis (FGL2, TGFB1, COTL1) potentially contributing to tissue damage in severe COVID-19 (154). Here, FGL2 is linked to COVID-19.