PBPC harvesting was performed in two patients with advanced-stage low-grade non-Hodgkin's lymphoma after mobilization with dexa-BEAM chemotherapy plus G-CSF. The collected grafts were subjected to immunomagnetic purging using B cell-specific moAbs and paramagnetic beads. Immunophenotypic and/or molecular analysis of the resulting products (PCR amplification of t(14;18) or CDR-III rearrangements) demonstrated successful depletion of lymphoma cells. Rapid and durable hematopoietic recovery occurred after reinfusion of the purged grafts following myeloablative radiochemotherapy (9-10 days to neutrophils > 0.5 x 10(9)/l; 9-11 days to platelets > 20 x 10(9)/l). We conclude that effective immunomagnetic purging of PBPC grafts is feasible without affecting engraftment.