CXCL2 and colitis: However, the increase in Cxcl2 and Il-1β mRNA expression was significantly suppressed in the colons of IL-4Rα-/- colitis mice (Figure 3C; Cxcl2; 5.3 ± 1.7 in WT colitis, 0.5 ± 0.3 in IL-4Rα-/- colitis; p < 0.05, Il-1β; 6.6 ± 2.1 in WT colitis, 0.3 ± 0.1 in IL-4Rα-/- colitis; p < 0.01).