Intestinal macrophages in patients with Crohn’s disease induce the Th1 and Th17 polarization of naïve CD4+ T cells, which seems to be caused by the accumulation of immature macrophages in the total macrophage population of patients with Crohn’s disease (Kamada et al., 2009; Ogino et al., 2013). Here, CD4 is linked to Crohn disease.