Cellular therapy refers to the use of live cells to replace or repair a damaged organ system. The first widespread use of this approach occurred more than 50 years ago when hematopoietic stem cells (HSCs) from the bone marrow of a healthy donor (allogeneic) were used to replace the hematopoietic system of a recipient after it was ablated during chemo/radio therapy of leukemia, the recipient’s hematopoietic system being “collateral damage” during the eradication of the unwanted leukemia cells.
Explore this issue:November 2008
This approach was later extended to the use of autologous stem cells in various malignant conditions such as breast cancer, allowing the use of more intense chemotherapy. In this context, the therapy is referred to as “hematopoietic stem cell support.” This principle was adopted for treating severe autoimmune disease more than 10 years ago in patients who failed to respond to conventional immunosuppression but in whom the marrow toxicity restricted dose escalation. Over 1,000 autoimmune disease patients have been treated, with around 30% achieving sustained remission.
Recently another cell, the mesenchymal stem cell (MSC), has been applied to the treatment of autoimmune disease. The concept is completely different from HSC in that pretreatment with chemotherapy is not required, and the MSCs are thought to home in on damaged tissue and exert a local paracrine healing effect. This article will review the basis of this novel treatment and results of recent trials.