The management of MS has advanced rapidly during the past few decades. In 1992, there were no FDA-approved therapies for MS. In 2015, we have 13 approved treatments for altering the course of MS. Unfortunately, gaps in our knowledge remain. We have no approved options for progressive forms of MS and for many, the current treatment options are not enough to completely stop the course of their MS. Could stem cells be the magic bullet we are looking for? What types of stem cell treatments are there? Do stem cells have the potential to reverse disability? In this article we will look at hematopoietic stem cell transplants, mesenchymal stem cells and for-profit stem cell clinics in the U.S. and abroad.
MS is an autoimmune disease resulting from complex interactions between genetic and environmental factors, resulting in an immune attack that destroys myelin and the underlying axons themselves. Like other autoimmune diseases, including rheumatoid arthritis and systemic lupus, MS represents an immune system gone awry. As noted, there are 13 FDA-approved disease modifying therapies. For some people with MS, these therapies may be quite effective in slowing the progression of disability, decreasing relapse frequency and helping prevent new MRI lesions. Our current treatments are not always effective enough for some people, however.
Host vs donor
What if we could “reboot” the immune system of the person with MS and give them an immune system that does not attack myelin? Sometimes this happens during the course of treatment of another health problem like certain cancers. During the treatment of some cancers, bone marrow transplants are used. These are typically allogeneic transplants, meaning that the stem cells used for the transplant come from someone other the patient. This is typically a brother, sister or an unrelated donor who is matched as closely as possible. Cells from umbilical cord blood can also be used. Once the cells from the donor are harvested, the recipient is treated with high doses of chemotherapy to kill any cancer. This chemotherapy also wipes out the recipients existing immune system The donor cells are then given to the recipient by vein and a new immune system is generated in the bone marrow. This new immune system is essentially that of the donor and not the recipient. The person with MS who gets an allogeneic bone marrow transplant to treat their cancer may have added benefit of treating their MS as well. They have been given a new immune system, one that does not attack myelin. Obviously, this is not the way we want to resort to treating MS. Allogeneic stem cell transplants require the long-term use of drugs to help prevent a war between the new immune system and the recipient. When the new immune system attacks the recipient, we call that graft versus host disease. When the recipient’s remaining immune system attacks the new immune system, we call that host versus graft disease. In addition to these complications, there is the risk of serious infections due to immune suppression from the initial high-dose chemotherapy, or the long-term lower dose immune suppressant drugs.
This brings us to a procedure called autologous hematopoietic stem cell transplantation or HSCT for MS. In contrast to the allogeneic stem cells from another individual, autologous stem cells come from the patient’s own bone marrow. There are several advantages. No donor needs to be identified and there is no risk of graft versus host or host versus graft disease. This eliminates the need for long-term immune suppressant drugs. There are still, however, the risks associated with the high-dose chemotherapeutic agents used in the initial shut down (immune ablation) of the immune system.
When other routes fail