Theoretically, corticosteroid therapy might have benefit for severe COVID-19 patients when cytokine storm occurs, as it can exhibit immunosuppressive effects through inhibiting NF-κB signaling; inhibiting the synthesis of proinflammatory cytokines including IL-1β, IL-2, IL-6, TNF-α, IL-17, and granulocyte-macrophage colony-stimulating factor; and reducing the proliferation, activation, differentiation, and survival of T cells and macrophages (18, 41). Here, CSF2 is linked to COVID-19.