OBJECTIVETo study the effect of growth factor-primed donor hematopoietic stem cells infusion (GPBSCI) as an early adoptive immunotherapy.

METHODSTwelve patients with high-risk leukemia received prophylactic GPBSCI after allogeneic hematopoietic stem cell transplantation (allo-HSCT). Out of the 12 patients, two were Ph(+) ALL in CR(1), one ALL in CR(2), one refractory ALL, three AML (one in relapse, one refractory disease, one in CR(3)), four CML in advanced stage and one myelodysplastic syndrome-refractory anemia with excess blast (MDS-RAEB).

RESULTSSixteen infusions were performed in the 12 patients, including 5 infusions were performed within +90 days post-SCT. The median mononuclear cells (MNC) and CD3(+) cells infused for GPBSCI before +90 d were 1.00 (0.95 - 1.24) x 10(8)/kg and 0.53 (0.39 - 0.63) x 10(8)/kg, and after +90 d were 2.27 (1.00 - 4.30) x 10(8)/kg and 1.15 (0.55 - 2.10) x 10(8)/kg, respectively. Four patients developed grade I - II acute GVHD, and one grade III acute GVHD. Seven patients developed chronic GVHD, of which four cases were extensive. Two patients had no transfusion related GVHD. No transfusion related pancytopenia was observed. Ten patients survived disease-freely at 563 (415 - 728) days of follow-up. Two patients died of leukemia relapse after GPBSCI.

CONCLUSIONAllo-HSCT with prophylactic GPBSCI could maximize graft-versus-leukemia effect with few fatal complications and might be a potentially curative strategy for hematological malignancy patients with high risk of relapse.