Multiple sclerosis (MS) involves the deterioration of the nervous system as a result of immune attack. Because MS is thought to be a disorder that is mediated by the immune system, treatments developed to combat the disorder often involve inhibiting the immune system to keep it from successfully attacking the brain and spinal cord. However, though some of these therapies can slow MS, most patients reach a point where therapy stops working, and the disease inevitably progresses. In a paper published in the esteemed Journal of the American Medical Association (JAMA) in 2015, researchers show that a new approach to MS therapy involving stem cell transplantation improves the symptoms associated with MS, as well as quality of life for patients, and that these improvements are sustained over a 6 month follow up period.
Unlike traditional MS therapies that suppress the immune system, autologous hematopoietic stem cell transplantation (HSCT) is aimed at instead resetting the immune system. It involves storing stem cells from the patient’s blood or bone marrow while the patient’s remaining immune cells are attacked with chemotherapy. The stem cells are then reintroduced back into the patient’s blood and eventually produce new cells that repopulate the immune system.
Prior to this publication, a nonmyeloablative regimen of HSCT shown to improve neurological symptoms, as well as quality of life in over 20 patients at Northwestern University in Chicago. In the current study, researchers analyzed all of the patients who underwent this therapy at Northwestern and included a follow-up analysis of these patients 6 months after the conclusion of their treatment regimen. This research took place over about 10 years and involved over 100 people with MS.
The patients in the study were treated with nonmyeloblative HSCT over approximately 10 days in the hospital and evaluated in terms of outcomes related to treatment safety, changes in disability, relapses, and disease activity measured by magnetic resonance imaging (MRI). The treatment appeared relatively safe, causing no deaths or serious infections. However, 7 people in the study developed thyroid disorders, and 7 people developed immune-mediated thrombocytopenia, a bleeding disorder that can be serious.
When looking at all the patients treated in the study, the researchers found that half of them had improved disability scores 2 years after treatment, and 64% showed this improvement 4 years after treatment. Upon closer analysis, the researchers found that though those with secondary-progressive MS and those who had the disease for more than 10 years did not show improvements in their disability scores, those with relapsing-remitting MS and those who had the disease for less than 10 years did show improvements.
While this study was an observational one, without a control group, it demonstrates the significant potential for stem cell therapies in treating MS. Randomized control trials, which are currently supported by the National MS Society, will help clarify how exactly stem cell therapies can help those with MS and other neurological conditions.
Burt, R.K. (2015). Association of Nonmyeloablative Hematopoietic Stem Cell Transplantation With Neurological Disability in Patients With Relapsing-Remitting Multiple Sclerosis. JAMA, 313(2), 275-284.