CCL2 and COVID-19: We evaluated the levels of IFN-α, IFN-γ, TNF-α, IL-1Ra, IL-2, IL-6, IL-7, IL-10, CCL2, CCL3, CXCL8, CXCL10 and GCSF in the serum and compared them among COVID-19 severity groups by Kruskal-Wallis test and stratified by polymorphism alleles.