When inflammatory mediators were measured in bronchoalveolar lavage fluid on different days post-infection, significantly lower levels of proinflammatory cytokines (IL-1β, IL-6 and TNF-α), immunomodulatory cytokines (GM-CSF, IL-12 p40, IL-17) and chemokines (MCP-1, MIP-1α) were detected in the TLR 4 deficient mice compared to the wild type. Here, IL6 is linked to infection.