CCL2 and respiratory system disorder: Among 48 cytokines/chemokines, evaluated by multiplex analysis in patient plasma, 6 (IL-6, CXCL-10, HGF, MIG, MCP-1, and G-CSF; Supplementary Table S2) were identified as highly significant in COVID-19 patients compared to non-COVID-19 respiratory disease controls (p-value < 0.0001) (Figure 2).