Autologous stem cell transplantation for autoimmune diseases: issues in protocol development

For patients with autoimmune disease resistant to conventional therapy, aggressive strategies employing high dose chemoradiotherapy and autologous stem cell transplant appear to be warranted. Support for this approach comes from animal studies employing marrow transplantation, which have shown promising results. Likewise, longterm control of autoimmune disease has been demonstrated in some survivors of allogeneic transplants for malignancy who incidentally had preexisting autoimmune disease. Initial strategies for autografting will use intensive transplant regimens incorporating cyclophosphamide with or without total body irradiation. Peripheral blood stem cell grafts purified by CD34 selection will be depleted of lymphocytes, and lead to rapid hematologic reconstitution after treatment. Close monitoring for disease responses, adverse effects of intensive immunosuppression, and longterm sequelae of high dose therapies will be required. Initial studies are best performed as close collaborations between rheumatologists and transplant specialists in appropriate research centers.