IL6 and COVID-19: In contrast, the expression level of IL-6 was only upregulated in vitro, in SARS-CoV-2 infected AECs (Fig. 2D, log-fold of 2.9 ± 0.3; P = 0.001); and not in nasopharyngeal swabs or lung autopsies of COVID-19 patients (Fig. 2E,F).