IL2 and neoplasm: To investigate whether T-CD3εζ28-GFP cells were activated by tumor cells secreting BiTEs, the concentrations of IL-2 and IFN-γ in the supernatant from the co-culturing medium of effector T and HeLa-EGFRvIII-BiTE cells were detected using enzyme-linked immunosorbent assay (ELISA).