IL15 and neoplasm: A significant increase in IFNγ and TNFα was only observed when IL-2, IL-15, and TGFβ were present (Figure 2D) after the initial cytokine activation, suggesting that an initial activation signal (either cytokine or tumor-induced) and a prolonged culture with IL-2 are required for TGFβ to induce cytokine hyperproduction.