IL6 and COVID-19: Of note, we noticed that relatively lower expression levels of IL6R was observed in BALF of COVID-19 patients compared with healthy individual (Supplementary File 1), and there are no significant differences in PBMC (Figure 1(E) and Supplementary File 1), suggests that IL-6/IL6R axis of cells in BALF and PBMC might not be involved in the pathophysiology of COVID-19 disease.