CCL2 and COVID-19: Interestingly, higher levels of various cytokines such as IFN-γ (Th1), interleukins IL-1β, IL-2, 6, 7, 8, 17, monocyte chemoattractant protein-1 (MCP-1/CCL2), IFN-γ induced protein 10 (IP10), tumor necrosis factor-α (TNF-α), macrophage inflammatory protein-1α (MIP-1α/CCL3) and granulocyte-colony stimulating factor (G-CSF) have been reported in severe COVID-19 patients [2,30].