CCL2 and infection: The initial infection induces various protective inflammatory responses in the host, including an increase in the expression of pro-inflammatory cytokines such as interferon (IFN)-γ, interleukin (IL)-1, IL-6 and IL-12, as well as in chemokines such as C-C motif chemokine ligands (CCL) including CCL-2 (also known as monocyte chemoattractant protein-1) and CCL-5 (also known as RANTES), as well as C-X-C motif chemokine ligands (CXCL) including CXCL2 (also known as macrophage inflammatory protein-2 α) and CXCL8 (also known as IL-8) [33,34].