SUCCESSFUL ENGRAFTMENT AFTER AUTOLOGOUS TRANSPLANTATION OF 1O-DAY CULTURED BONE-MARROW ACTIVATED BY INTERLEUKIN-2 IN PATIENTS WITH ACUTE LYMPHOBLASTIC-LEUKEMIA

Disease recurrence remains the major problem in autologous bone marrow transplantation (BMT) for hematologic malignancies, To improve the th erapeutic efficiency of autologous BMT, we investigated the use of aut ologous marrow activated in vitro with interleukin 2 (IL-2) to generat e killer cells for in vivo purging, A feasibility trial was initiated in 5 patients with poor prognosis acute lymphoblastic leukemia, who we re transplanted, after marrow ablative therapy, with autologous marrow cultured for 10 days with 10(3) units of IL-2/ml. A highly significan t increase in NK activity and an induction of LAK activity were observ ed after incubation, Patients received 0.64 to 1.56 x 10(8) cultured B M cells/kg and 1.87 to 44.8 x 10(4) CFU-GM/kg. Four patients engrafted and achieved granulocyte counts >0.5 x 10(9)/l on days 35, 24, 36 and 22 after transplant, Three of these patients showed platelet recovery to >50 x 10(9)/l on days 25, 42 and 40 after transplant, One patient remained thrombocytopenic until relapse, One patient died on day 12 af ter transplant, This study demonstrates that cultured BM activated wit h IL-2 can be used successfully for hematological rescue in the clinic al setting.