Hematopoietic stem cell therapy of autoimmune diseases.

Hematopoietic stem cell transplantation is a new therapy for severe autoimmune diseases. Patients who have failed standard therapies and are at high risk of subsequent morbidity and mortality are being considered as candidates. Early results are encouraging. However, the number of patients treated is limited, only short-term follow-up is available, the mechanism of improvement or stabilization is unknown, and the procedure has the potential for life-threatening toxicity.