CCL2 and severe acute respiratory syndrome: The elevation of Th1 cytokine IFN-γ, inflammatory cytokines IL-1, IL-6 and IL-12 and chemokines IL-8, MCP-1 and IP-10 confirmed the activation of Th1 cell-mediated immunity and hyper-innate inflammatory response in SARS through the accumulation of monocytes/macrophages and neutrophils [17].