CCL2 and bacterial infectious disease: In the case of systemic bacterial infection, resident CD68+ Kupffer cells engulf and kill the bacteria, and CD11b+ Kupffer cells/Mφs are recruited to the liver via the MCP-1/CCR2 axis; CD68+ resident Kupffer cells produce MCP-1 and CD11b+ Kupffer cells/Mφs express CCR2/MCP-1 receptors and are recruited to the liver13.