Cloned colony-stimulating factors have been shown to accelerate myeloid recovery following autologous bone marrow transplantation. Studies with granulocyte-macrophage colony-stimulating factor (GM-CSF) have demonstrated efficacy in accelerating neutrophil recovery in patients rescued from myeloablative therapy. In our previous study, however, the subset of patients who received monoclonal antibody and complement purged bone marrow grafts followed by GM-CSF recovered neutrophil counts at the same rate as placebo-treated patients. We have now performed a phase II trial to assess whether granulocyte colony-stimulating factor (G-CSF) results in accelerated engraftment in this group of patients. Twenty-three consecutive patients with recurrent non-Hodgkin's lymphoma received G-CSF (10.5 +/- 1.2 micrograms/kg per day) following myeloablative therapy consisting of etoposide (60 mg/kg), cyclophosphamide (100 mg/kg), and either carmustine (15 mg/kg) or fractionated total body irradiation (1200 cGy). All patients received bone marrow grafts which had been purged with a panel of monoclonal antibodies directed against either B or T cell determinants plus complement. Peripheral blood mononuclear cells (PBMC) were not administered to any of the patients in this study. Twenty-one patients engrafted at a median absolute neutrophil count (ANC) greater than 500/microliters at day 12 and ANC greater than 1000/microliters at day 14. The time to myeloid engraftment was significantly shortened compared to our previous experience with either GM-CSF or placebo following identical preparatory regimens (p < 0.01). G-CSF is capable of accelerating myeloid engraftment in patients receiving monoclonal antibody purged bone marrow grafts following myeloablative therapy when compared to historical control groups treated with placebo or GM-CSF.