CCL2 and bacterial infectious disease: Classical type 1 cytokines and chemokines (e.g., IL-2, IL-12, IFN-γ, TNF-α, MCP-1/CCL2, MIP-1α/CCL3, and RANTES/CCL5) were predominantly induced around the peak of bacterial infection, and then decreased as bacterial replication was controlled at 28 dpi.