CD274 and colitis: At 8 h after intraperitoneal injection of PD-L1-Fc/Oxi-αCD nanoparticles, the H2O2 concentration in the colonic tissue of the colitis mice decreased significantly, while the H2O2 concentration remained little changed in the colonic tissue of the normal mice (Supplementary Fig. 8), indicating that the PD-L1-Fc/Oxi-αCD nanoparticles had reached the inflammatory site and reacted with the ROS.