IL15 and inflammatory bowel disease: Additionally, we analyzed immune cell-infiltrating characteristics in the intestinal mucosa in IBD and found that UC was characterized by M1 macrophages (P < 0.001); M0 macrophages (P < 0.001); neutrophils (P < 0.001); eosinophils (P < 0.01) (Figures 1E,I); and the inflammatory factors IL18, IL8, and IL15 (Figure 1H).