IL21 and neoplasm: Figures 2A-D indicate that compared with mice immunized with the B16F10 cells, the serum cytokine levels of IFN-γ, TNF-α and IL-4 were significantly increased after the mice were immunized with the tumor vaccine B16F10/GPI-IL-21, whereas the serum TGF-β level was markedly decreased, which was statistically significant (A-D).