OBJECTIVES: I. Compare the incidence of acute graft versus host disease (GVHD) grades II-IV and extensive chronic GVHD in chronic myeloid leukemia patients treated with purged donor lymphocyte infusion (DLI) processed with CD8 high density microparticles (HDM) vs unpurged DLI following nonmyeloablative, HLA identical sibling peripheral blood stem cell transplantation. II. Compare the rates of complete cytogenetic, clinical, and hematologic remission and mortality and GVHD in patients treated with these regimens. III. Determine the efficacy of CD8 HDM in depleting greater than 95% of CD8+ cells in donor lymphocytes. IV. Compare the safety and toxicity of these regimens in these patients.