CCL2 and pneumonia: For example, the concentrations of cytokines such as interleukin-6 (IL-6), interleukin-8 (IL-8), interleukin-15 (IL-15), and monocyte chemoattractant protein-1 (MCP-1) are markedly elevated, mirroring the cytokine storm observed in severe SARS-CoV-2-induced pneumonia (24–27).