CXCL1 and infection: At early time points, Fpr2-/- mice showed a significant decrease in CXCL1, CXCL2, IL-1β, CCL2, GM-CSF, IL-6, and CCL3 levels at 1 hour and 3 hours after infection, and an increase in IL-22 and IL-23, but there is no change in TNF-α, as compared with WT mice (Figures 5A, B).