MUC5B and COVID-19: In large airway tissues, genes related to the mucosal layer (MUC4, MUC5AC, MUC5B) as well as cytokine-mediated signaling pathway genes (CCL20, CXCL1, CXCL6, CXCL6, MMP1) and type I interferon genes (IFIT3, ISG15, STAT1, MX1) were upregulated in COVID-19.