Removal of neuroblastoma cells from bone marrow with monoclonal antibodies conjugated to magnetic microspheres.

Monoclonal antibodies bound to polystyrene microspheres containing magnetite have been used to remove tumour cells from bone marrow destined for autologous transplantation. The small magnetic beads can be targeted to the surface of tumour cells to render these magnetic. A flow system using permanent samarium cobalt magnets effects the rapid and efficient removal of "magnetic" tumour cells from bone marrow. The system is designed to be used with any type of tumour cell, so that by changing panels of monoclonal antibody it can be used for "cleaning" the bone marrow in many different malignancies.