CCL2 and COVID-19: Next, we investigated more deeply the interplay between IFNs and immune markers whose elevation in circulation has been associated with poor prognosis in COVID-19, including interlelukin (IL)-22, SAA, IL-10, IP-10, IL-6, IL-8, MIP-3α, IL-1RA, MIP-1α, TNF-α, MCP-1, and MCP-4 (Fig. 7E and Dataset S20) (39, 40, 43, –45).