CCL2 and COVID-19: Transcriptomic studies revealed remarkably enhanced expressions of CCL2, CXCL8, CSF3, CSF2, and CXCL10 in Calu-3 cells infected with SARS-CoV-2 [34], inflammatory factors that were shown to be strongly elevated in the serum of patients with severe clinical symptoms of COVID-19 [43,44].