Levels of IL-1β, IL-6, CCL2, CCL3, CXCL1, and CXCL2 were significantly greater 6 h following infection than in mock-infected mice (P < 0.05) but were similar among wild-type, CCR2−/−, and Nr4a1−/− mice (Fig. 11). This evidence concerns the gene CXCL2 and infection.