Here, increased expression of IL-15 was seen in IL-1rn-/- mice, this is in agreement with Liu et al (2000), who showed increased expression of IL-15 by macrophages in the inflamed ileum of patients with Crohn's disease and that IL-15 increased local T cell activation and induced proinflammatory cytokine production by T cells and macrophages. Here, IL15 is linked to Crohn disease.