CD274 and neoplasm: The amount of tumor-infiltrated CD45.1+ CD8+ T cells pre-incubated with sEVWT or sEVS345D was significantly lower compared to those treated with sEVS345A, while there was no difference among the infiltrated CD45.2+ CD8+ T cells treated the same set of EVs, but having their PD-L1 blocked (Fig. 5e).