CXCL1 and bacterial pneumonia: Because cytokines are important regulators of the inflammatory response to bacterial pneumonia [45], we measured pulmonary (TNF-α, IL-6, IL-10, CXCL1) and systemic (TNF-α, MCP-1, IL-6, IFN-γ, IL-10, IL12p70) cytokine and chemokine levels (Table 1).