Furthermore, to test whether co-assembly affect the PD-L1 blocking ability of EH at the cellular level, a competition experiment between EH monomer, EH assembly, EH@Ag2S and the natural ligand PD-1 was performed to verify the checkpoint blocking ability. As shown in Fig. , when PD-1 was incubated with MC38 cells, a large amount of PD-1 was distributed on the cell membrane. However, when PD-1 was co-incubated with EH monomer, EH assembly, and EH@Ag2S with cells, respectively, the localization of PD-1 on cell membrane was disturbed, suggesting that different forms of EH did not affect the PD-L1 blocking ability of EH itself. In addition, to study the tumor inhibition effect, tumor cells were co-incubated with T cells after incubation with the EH, antibody and EH@Ag2S, respectively (Fig. ). As shown in Fig. growing number of T cells surrounded the cancer cells with increasing incubation time.