As reported by Pereira et al. (1987), enlargement of the spleen, “splenomegaly,” was detected in IBD model mice (Figure 1A), and a significant increase in the transcriptional expression of the Th1 cytokine interferon-γ (IFN-γ) and Th17 cytokine interleukin-17 (IL-17) was detected (Figures 1B,C), without any changes in the Th2 cytokine IL-4 (not shown). Here, IL4 is linked to inflammatory bowel disease.