CD274 and colitis: Flow cytometry analysis showed decreased frequencies of DCs, macrophages and neutrophils in colitis mice treated with soluble PD-L1-Fc, PD-L1-Fc/PLGA nanoparticles or PD-L1-Fc/Oxi-αCD nanoparticles compared with untreated colitis mice or colitis mice treated with Blank/Oxi-αCD nanoparticles, with more obvious decreases in the frequencies of these cells in PD-L1-Fc/Oxi-αCD nanoparticles-treated colitis mice (Figs. 5A–C, 6A–C, Supplementary Fig. 14A, –C and  15A, –C).