In particular, the levels of serum and bronchoalveolar lavage fluid proinflammatory chemokines and cytokines (CCL2/3, CXCL10, IL-6/10, IFN-γ, and TNF-α) are highly correlated with disease severity and progression in patients with COVID-19 (5, 34, 35). This evidence concerns the gene IL6 and COVID-19.