MUC5AC and COVID-19: To address the above research questions regarding mucin expression in COVID-19, we applied validated RT-PCR assays integrated with clinical data to examine the transcriptional mucin landscape in the blood of patients with symptomatic COVID-19, symptomatic patients without COVID-19, and healthy controls and investigated the effect of COVID-19 drugs on SARS-CoV-2–induced mucin expression in pulmonary epithelial cells.