IL2 and neoplasm: It was found that manufacturing and infusing MTX–EVs were safe, without toxic effects, and that infusion of MTX–EVs led to notable reductions in the number of tumor cells and CD163+ macrophages in MPE, as well as to the stimulation of IL-2 and IFN-γ release, which can activate cytotoxic T lymphocyte (CTL)/T helper 1 (TH1) responses and elicit anti-tumor immunity [89].