Figure 1.

The expression of PD-1 and PD-L1 in the colonic mucosa of patients with ulcerative colitis. (A) The expression of PD-1 was significantly increased in the colonic mucosa of patients with UC compared to that of the normal controls. (B) The expression of PD-L1 was also significantly increased in patients with UC. (C, D) When compared the active inflammation in the mucosa, the expression of PD-1 was significantly higher in mucosa with active inflammation. However, the level of PD-L1 was not significantly different according to the mucosal inflammation. PD-1, programmed death 1; PD-L1, programmed death-ligand 1; UC, ulcerative colitis.