CCL2 and COVID-19: The level of inflammatory factors in patients with COVID-19 are increased, among which are IL-1RA, IL-1B, IL-7, IL-8, IL-9, IL-10, granulocyte-macrophage colony stimulating factor (GM-CSF), IFN-γ, fibroblast growth factor (FGF), granulocyte-colony stimulating factor (G-CSF), interferon-γ-inducible protein (IP10), macrophage inflammatory protein 1 alpha (MIP1A), platelet-derived growth factor (PDGF), monocyte chemoattractant protein (MCP1), vascular endothelial growth factor (VEGF), and tumor necrosis factor (TNF-α).