CCL2 and acute respiratory distress syndrome: Research derived from SARS infection cases correlated acute respiratory distress syndrome (ARDS) to the early activation of IFN-γ and IFNα and upregulation of proteins encoded by ISGs, pro-inflammatory cytokines, and chemokines, particularly IL-6, -8, CXC-chemokine ligand 10 (CXCL10), and CC-chemokine ligand 2 (CCL2) (Tang et al., 2005; Baas et al., 2006).