IL6 and COVID-19: As consistent with our results, it was indicated that miR-18a-5p mimic significantly reduced inflammatory factors including IL-6, IL-8, IL-1β, and tumor necrosis factor (TNF)-α release, decreased the degranulation rate and histamine release rate of cells [33], this may explain the increased serum level of IL-6 in our severe COVID-19 patients, especially the nonsurvival ones.