IL2 and neoplasm: To enhance direct cell–cell interactions between tumor cells and immune cells, various types of fusion molecules were produced and applied, for example, anti-tumor associated antigen (TAA)-antibodies fused with cytokines [8], TAA linked with a molecular chaperone [9], scFv-scTRAIL [10], OVA-gp100 [11], interleukin-2 (IL-2)-TCR [12], etc. By this way, cell–cell crosstalk is promoted and biological processes are accelerated, exerting enhanced antitumor effects [13].