IL2 and leukemia: To date, first trials and ongoing clinical phase I/II studies show the feasibility of using freshly purified or interleukin-2 (IL-2) activated NK-DLIs for the treatment of high risk patients suffering from leukemia or tumors in both, non-transplant settings and after haplo-SCT as an additional immunotherapy [1]–[3], [12]–[16].