Notably, there was an increase in the proportion of infiltrated immune cells (CD45+), CD4+ and CD8+ T cells, macrophages (CD11b+F4/80+), and neutrophils (CD11b+Gr1+) in Smad4−/− mice during colitis compared with those in WT mice (Figure 3d,e), which was accompanied by enhanced IFNγ levels (Figure 3f). Here, CD8A is linked to colitis.