CCL2 and COVID-19: Severe COVID-19 cases exhibit a dysfunctional immune response characterized by higher blood plasma levels of interleukin (IL)-1β, IL-2, IL-6, IL-7, IL-10, granulocyte colony-stimulating factor, interferon gamma-induced protein-10 (C-X-C motif chemokine ligand 10 (CXCL10)), monocyte chemoattractant protein-1 (C-C motif chemokine ligand 2 (CCL2)), macrophage inflammatory protein 1α (CCL3) and tumour necrosis factor, which mediate widespread lung inflammation and fail to successfully eradicate the pathogen1,4–7.