OBJECTIVETo observe the therapeutic efficacy of 131I-labeled granulocyte macrophage colony-stimulating factor (GM-SCF) in SCID mouse-acute myeloid leukemia model, and the relationship between dose and effect.

METHODSSCID-mouse acute myeloid leukemia model was established by injecting HL-60 cells through tail vein. GM-CSF was labeled with 131I by the chloramines-T method. SCID mice were randomly divided into 6 groups. Groups I, II and III treatment groups were given 9.25 x 10(5), 22.20 x 10(5) and 37.00 x 10(5) Bq of 131I-GM-CSF, respectively. Group IV was given 131I. Group V was given blending of 131I and GM-CSF. Group VI was control. Changes of HL-60 cells in blood and marrow, as well as white blood cells, red blood cells and platelets in blood were detected. Survival time of the SCID mice was calculated.

RESULTIt was observed that WBC, HL-60 cells in blood and marrow were less in treatment groups than that in control groups, especially in groups II, III. After 2 weeks of treatment, BPC of II, III groups increased remarkably (P < 0.01). Survival time of the SCID mice was prolonged in treatment groups (P < 0.01), especially in group III, the longest survival time of 60 days.

CONCLUSION131I-GM-CSF could increase leukemic SCID mice survival rate. The therapeutic efficacy of low dose and mediate dose of 131I-GM-CSF is dose-dependent. 131I-GM-CSF is an effective radiation immunity therapy for leukemic mice.