AUTOLOGOUS TRANSPLANTATION IN PATIENTS WITH ACUTE MYELOID-LEUKEMIA INFIRST REMISSION WITH IL-2-CULTURED MARROW OR PERIPHERAL-BLOOD STEM-CELLS FOLLOWED BY IN-VIVO IL-2

Background: Autologous transplantation using the patient's marrow or p eripheral blood stem cells is still plagued by high relapse rates most ly due to the lack of a graft-versus-leukemia (GVL) effect. We have de veloped a strategy to combine immunological purging of the autograft a nd posttransplant immunotherapy.Material and Methods: Bone marrow (BM) and/or peripheral blood progenitor cells (PBPC) were harvested from p atients with AML who had poor prognostic features. Leukapheresis after priming with G-CSF was performed immediately after entering first rem ission and the harvested cells were cultured for 8 days in the presenc e of interleukin-2 (IL-2), that supports the expansion and activation of cytotoxic cells. The blood cells were then harvested from the cultu re containers and given to the patient who had received myeloablative chemotherapy during the culture period. Patients were given daily inje ctions of IL-2 for the first week in order to maintain the cytotoxic a ctivity of the transplanted blood cells. Results: Over the last years we have refined this technique and have treated 19 patients. Side effe cts have been acceptable with most patients developing high temperatur es during posttransplant IL-2 treatment. However, all finished the pre scribed course. Transplantation of PBPC either alone or together with BM resulted in much faster engraftment than transplantation with BM al one. Disease-free survival in these high-risk patients is encouraging. Conclusion: Culture of BM and/or PBPC in IL-2 for 1 week allows both immunologic purging and adoptive immunotherapy to be applied in patien ts receiving autografts for AML.