Multiple sclerosis (MS) is a debilitating illness in which the immune system begins to attack the insulation (myelin) that surrounds the neurons in our brains. The damage of this attack effectively short circuits the messages our brain send to the body resulting in troubles with balance, coordination, muscle strength, sensations and tremors. There is no known cause for MS but research has suggested that there is a genetic component, related to your body’s inflammatory response, as well as a potential link between viral infection (Epstein Barr and Herpes viruses) and MS development. These viruses infect the majority of the population, 90% in the case of Epstein Barr, and so there must be some other factor that contributes to MS development or the rate of MS in the population would be higher. As it is, MS occurs in approximately 240 people out of every 100,000 Canadians. It was suggested by a researcher in Italy that narrowed veins may be the cause of MS but recent research has shown there appears to be no link between narrowed veins and MS and so the search for a cause continues.
MS can occur as a progressive disease with ever-present symptoms or as a relapsing and remitting disease where people experience periods of symptoms and periods without symptoms. Currently there are few therapies and treatments available for MS and the ones we have are usually limited to dampening the immune system using steroids or other immunosuppressant’s. These treatments are often applied when a person has an attack or exacerbation of their MS symptoms as in the relapsing and remitting diseases. Many researchers spend their days looking for a way to halt the damage done by the immune system for good and this is where a new clinical trial looking at resetting patient’s immune system may hold some promise.
Published in JAMA Neurology, this three year interim report shows how resetting the immune system of patients with relapsing and remitting MS affects the progression of their disease. To reset their immune system, the patients were given various chemotherapy drugs designed to kill off all the immune cells, including those that are responsible for attacking the neurons. The patients then had their immune system repopulated using immune stem cells transplanted back into their body. These stem cells were removed and frozen prior to destruction of their immune system. The hope was that this would act like hitting the reset button and prevent the immune system from attacking the neurons and doing further damage. The researchers saw that patients who had this treatment were more likely to stay in remission and also had some improvements in neurologic function.
The results of the trial are early but they are promising. If these results hold up for the full 5 years of the trial then it may be an option for people who have not had success with other forms of treatment. The concern with this procedure is that it can be relatively invasive and unpleasant. While the trial did not see many serious adverse effects, the treatment does require chemotherapy to delete the patient’s immune system and as such all the side effects of chemotherapy would apply to this treatment. Still, for people suffering from the disease, this may offer a possible treatment or it may spawn research into different ways of resetting the immune system. Larger trials are needed before this technique is deemed safe for general use but we may be able to hit the reset button on future autoimmune disorders too.