IL1B and staphylococcus aureus infection: To determine if the decreased inflammatory cells influx is dependent on inferior production of cytokines/chemokines following Staphylococcus infection, we measured the expression of cytokines (IL-6, IL-1β, and IFN-β) and chemokines (KC/CXCL1, CXCL2, and CXCL10) in lung homogenates, BALF or blood at 24 h after Staphylococcus challenge (Figures 2C–N).