IL2 and neoplasm: In contrast to T-cell harvesting from peripheral blood, TIL therapy harnesses the power of a patient’s own tumor fighting T-cells by isolating them from autologous tumor tissue (isolation step), growing and activating those cells ex vivo (expansion step), treatment with lymphodepleting chemotherapy prior to TIL infusion (pre-conditioning step), infusing expanded TILs, and supporting in vivo T-cell activation and proliferation post TIL infusion with high-dose interleukin-2 therapy (HD-IL-2) (153).