use of high dose immunoablative therapy with autologous hematopoietic stem cell transplantation for the treatment of severe autoimmune disease
Autologous (using patient’s own stem cells) hematopoietic stem cell transplantation is a method of increasing the intensity of chemotherapy that can be given to a patient with a severe autoimmune disease who is failing standard therapy. By collecting stem cells (CD34+) prior to chemotherapy, higher doses of cyclophosphamide (200 mg/kg) can be given to ablate the immune system because the patient can be rescued from bone marrow failure by reinfusion of the patient’s own stem cells. Some patients may also receive lymphoablative antibodies or total body irradiation to eradicate residual autoreactive cells. This stem cell transplantation strategy allows the patient to reconstitute their immune system without redeveloping their autoimmune disease or developing graft versus host disease. This procedure is most often used for treatment-resistant SLE, systemic sclerosis, multiple sclerosis, and other autoimmune diseases with varying success rates and a mortality rate as high as 8% at a cost of up to $100,000. Other immunoablative and/or transplantation strategies are also being investigated.