IL2 and neoplasm: We observed only small amounts of IL-2 in the supernatants of unmodified DCs, GFP-DCs or AFP-DCs which may be insufficient for the stimulation of T-cell proliferation and this may explain the failure of the AFP-DC vaccine to effectively control tumor growth compared with AFP/IL-2-DC, while a higher level of IL-2 production by the DCs was detected following IL-2 transfection.