IL6 and COVID-19: Our findings support the results of a previous study showing that IL-6 induces low HLA-DR expression and lymphopenia in patients with severe COVID-19 associated with immune dysregulation (Giamarellos-Bourboulis et al., 2020) and that the counts of circulating HLA-DR-positive cells were increased during convalescence in a patient with moderately severe COVID-19 (Thevarajan et al., 2020).