Fig. 1. Schematic illustration of engineering of PD-L1-Fc-loaded ROS-responsive nanoparticles for targeted treatment of colitis.

PD-L1-Fc-modified nanoparticles can target the inflamed colon via passing through the blood vessels around the inflammation site, and the loaded PD-L1-Fc is released in response to high levels of ROS in the microenvironment of the diseased colon, which then exerts its multiple biological activities by mediating the frequency of inflammatory cells or inflammatory cytokine production. NPs nanoparticles.