IL2 and neoplasm: Generation of tumor-infiltrating lymphocyte (TIL) cultures is performed by first culturing resected tumor fragments or tumor single-cell suspensions in medium containing IL-2 for 3–5 weeks followed by a rapid expansion protocol (REP) involving the activation of TILs using an anti-CD3 monoclonal antibody in the presence of irradiated peripheral blood mononuclear cells (PBMC) and IL-2 (2, 6, 7).