THERAPEUTIC EFFICACY OF RECOMBINANT HUMAN LEUKEMIA INHIBITORY FACTOR IN A PRIMATE MODEL OF RADIATION-INDUCED MARROW APLASIA

The therapeutic efficacy of recombinant human leukemia inhibitory fact or (LIF) was examined in a nonhuman primate model of radiation-induced marrow aplasia. Rhesus monkeys received 450 cGy of total-body, 1:1 mi xed neutron:gamma radiation. For 23 days thereafter, each monkey recei ved a daily subcutaneous injection of LIF or human serum albumin (HSA) at a dose of 15 mu g/kg body weight. Complete blood counts and white blood cell differentials were monitored for 60 days postirradiation. A dministration of LIF significantly decreased (P less than or equal to .05) the duration of thrombocytopenia (platelet count <30,000 or 20,00 0/mu L), ie, 9.3 days or 6.3 days, respectively, versus the HSA-treate d control monkeys, 12.2 days or 10.2 days, respectively. Treatment wit h LIF did not alter the duration of neutropenia (absolute neutrophil c ount <1,000/mu L) as compared with the HSA-treated control monkeys. Cy tokine administration did not exacerbate the radiation-induced anemia observed in the HSA-treated control monkeys. (C) 1994 by The American Society of Hematology.