CCL4 and influenza: Previous in vitro studies have shown that influenza infection induced the production of cytokines IFN-α, tumour necrosis factor (TNF)-α, IL-1, IL-6, and IL-8, and the mononuclear cell attractant chemokines CCL-3/MIP-1α, CCL-4/MIP-1β, CCL-2/MCP-1, CCL-7/MCP-3, CXCL-10/IP-10, and CCL-5/RANTES in human monocytes, epithelial cells, and rat alveolar or murine macrophages [29].