IL15RA and neoplasm: GT-00AxIL15 simultaneously binds TA-MUC1 as tumor target and IL-15R for immune activation, retaining wild-type IL-15 binding characteristics, i.e., binding to endogenous IL-15Rα and IL-15Rβγ, resulting in natural downstream-signaling and IL-15-mediated effects such as induction of activation and proliferation of immune effector cells.