Stem cells have the potential to develop into cells with special functions such as the nerve cells in the brain or the muscle cells of the heart. It is this potential that is a reason for researching their use in MS, as they might be able to repair damage to the nervous system or boost the immune system to prevent damage from happening.
Hematopoietic stem cell transplantation (HSCT) is a type of stem cell therapy that is being investigated as a treatment for MS. HSCT is currently still an experimental treatment that is only available as part of clinical trials. This review outlines the results from these studies, the safety and the effectiveness of the HSCT procedure.
The review found that HSCT treatment can reduce inflammation, reduce the number of relapses and slow down the progression of disability. Although treatment did not result in a freedom from disease activity, as although it reduced the number of immune cells and inflammation, loss of myelin and nerve cells was still seen. There are also several significant risks associated with treatment including development of autoimmune diseases, malignancies and death. Due to advances in knowledge and changes in the HSCT treatment in the last 10 -15 years, it is now safer than it was in the year 2000, although the risk of death is still just over 1 in every 100 people treated.
The authors suggest that HSCT could possibly be considered a treatment for people who have MS that is resistant to other treatments. However they conclude that the need for HSCT treatment will need to be re-evaluated against the increasing availability of other drug treatments that have a very similar benefits to HSCT but with less risks.
Stem cells are different from all other kinds of cells in the body as they are unspecialised, which means they are not already dedicated to having a specific function in the body. They have the potential to develop into cells with special functions such as the nerve cells in the brain or the muscle cells of the heart. It is this potential that is a reason for researching their use in MS, as they might be able to repair damage to the nervous system or boost the immune system to prevent damage from happening.
Hematopoietic stem cell transplantation (HSCT) is a type of stem cell therapy that is being investigated as a treatment for MS. The HSCT is an aggressive procedure that involves several stages:
First the stem cells are collected from the person with MS. These are either collected directly from their bone marrow using a needle and syringe to suck the cells from the bone marrow in the hip while under general anaesthetic. Or the person is given a drug that encourages the stem cells to leave the bone marrow and enter into the blood so they can be collected in a blood sample. The stem cells are then frozen. The person with MS is given high dose chemotherapy and sometimes radiotherapy to kill off their existing immune system. Their own stem cells are then defrosted and injected into the person with MS, where they multiply and recreate the immune system.
HSCT is currently still an experimental treatment that is only available as part of clinical trials. This review outlines the results from these studies, the safety and the effectiveness of the HSCT procedure.
How this study was carried out
This review looks at the current status of the research into stem cell treatment of MS. 23 published studies were examined and compared. The first study about HSCT in people with MS was published in 1997. In 1998 based on the evidence from the initial studies, a conference was held to discuss and create some guidelines for HSCT research, as there were several ethical and practical concerns.
The review outlines the results from the studies performed to date, the safety and the effectiveness of the HSCT procedure.
What was found
The review found that 538 people with MS had undergone HSCT since the creation of the 1998 guidelines. 336 people (62%) who received HSCT had primary or secondary progressive MS. Early trials included more people with progressive MS but more recent trials had included more people with relapsing remitting MS. All the studies reviewed were small trials ranging from 5-74 participants.
The review found several risks and side effects of HSCT treatment. These included:
- Disease reactivation causing a worsening of MS symptoms.
- Sepsis and urinary tract infections were reported in almost all studies. Sepsis is potentially life-threatening condition triggered by an infection, where the body's immune system goes into overdrive causing widespread inflammation, swelling and blood clotting.
- Reactivation of varicella-zoster virus, causing shingles and herpes simplex virus, causing cold sores or herpes.
- Development of autoimmune diseases, mainly autoimmune thyroiditis, where the body sees the thyroid, and the hormones it produces, as threats, attacks and destroy them.
- Malignancies, such as leukaemia.
- Treatment related mortality, this is defined as death due to causes unrelated to the underlying disease but considered related to the transplantation. Deaths that occurred as a consequence of transplantation ranged from 2.7% to 20% of people being treated in the studies that were reviewed. A recent analysis suggests that that the risk of death is now 1.3% or 1 person in every 100 treated. This reduction is due to changes in the way people are selected for the trials and also changes in the way that the procedure is done.
The review found that only four studies provided data and information on the long-term effects and safety of HSCT. Due to the differences in the participants' characteristics, treatment methods and ways of assessing the outcomes the authors found it was very difficult to compare the results of the studies directly and draw definitive conclusions.
The review found several effects of HSCT on people with MS. These included:
- Most studies found that in the two years following treatment participants EDSS score was less likely to increase, for most people it remained the same as it was just before treatment. This suggested that HSCT could prevent disability progression in the short term, but there currently is little evidence to confirm if disability progression can be stopped in the longer term.
- HSCT did not result in a freedom from disease activity. It reduced the number of immune cells and inflammation but loss of myelin and nerve cells was still seen.
- Treatment was more successful in people with MS who had relapsing remitting MS, a short disease duration and a lower EDSS score.
What does it mean?
The study shows that due to advances in knowledge and changes in the HSCT treatment in the last 10 -15 years, mean that it is now safer than it was in the year 2000, although the risk of death is still just over 1 in every 100 people treated.
The results suggest HSCT treatment can reduce inflammation, reduce the number of relapses and slow down the progression of disability. The authors suggest that HSCT could possibly be considered a treatment for people who have MS that is resistant to other treatments. However they conclude that the need for HSCT treatment will need to be re-evaluated against the increasing availability of other drug treatments that have a very similar benefits to HSCT but with less risks.
Radaelli M, Merlini A, Greco R, et al.
Autologous bone marrow transplantation for the treatment of multiple sclerosis..
Curr Neurol Neurosci Rep. 2014 Sep;14(9):478.
More about about stem cells
Stem cells are naturally occurring cells that differ from other cells in the body, as they are unspecialised, which means they are not already dedicated to having a specific function in the body. They have the potential to develop into different types of cell and it is this which is driving the scientific interest in their use as a possible therapy in multiple sclerosis.
Three possible theories as to how stem cell treatment might work in MS are being explored, stem cells might be persuaded to:
- Develop into nerve cells to repair damage to the brain
- Develop into oligodendrocytes to repair damage to myelin
- Boost the immune system to prevent damage
Although work with stem cells is still at a very early stage, there have been small clinical trials in people with MS in both Europe and the United States. This paper reviewed the work that has been done on the theory of boosting the immune system to treat MS.
Clinical trials in progress
Currently there are a number of stem cells trials ongoing in the UK. This includes a study part-funded by the MS Trust into a stem cell therapy at Frenchay Hospital in Bristol that aims to reduce the increase in disability that is commonly seen in people with a progressive form of multiple sclerosis. This trial started in 2012 and results are expected to be announced in 2017.
Interest in stem cell research is high and unfortunately, as the trials are only small scale at the moment, any opportunities are always massively over-subscribed. The MS Trust is not aware of any opportunities to get involved in stem cell research at the moment.
Stem cell treatments are being offered commercially on the internet, as are 'clinical trials' where the participants are expected to pay for treatment, these sites should be approached with great caution. In some instances, clinics have been found to be offering expensive treatments with no evidence that they work or are safe and providing little in the way of follow-up support for customers. The MS Trust is not currently aware of any ethical, authorised clinics using stem cells to treat MS outside clinical trials.
Hope or hype?
Stem cells do offer great potential but currently all stem cell treatments remain experimental and the consensus is that any treatment based on stem cells is still some years away. As well as studies to show that the stem cells can be used to repair or replace damaged parts of the body, a lot of work also needs to be done to ensure stem cells can be controlled and are safe to use.
Stem cell treatments for MS always seem to attract a great deal of media interest and not all of these reports are accurate accounts of what the studies have found. Prof Neil Scolding who is leading the stem cell research in Bristol wrote an article for Open Door on stem cells, including the media's reporting of research.
You can read more about MS research including how to tell good research from hype in Research and MS.
The NHS Choices website also has a helpful 'Behind the Headlines' section that takes a closer look at the research behind some of the top newspaper headings and examines what the study really found.
You can read more about stem cells in the A to Z of MS.
Research by topic areas...
Disease modifying treatments
Correale J, Chiquete E, Milojevic S, et al.
Assessing the potential impact of non-proprietary drug copies on quality of medicine and treatment in patients with relapsing multiple sclerosis: the experience with fingolimod.
Drug Des Devel Ther. 2014;8:859-67.
Read the full text of this paper
Bergvall N, Petrilla AA, Karkare SU, et al.
Persistence with and adherence to fingolimod compared with other disease-modifying therapies for the treatment of multiple sclerosis: a retrospective US claims database analysis.
J Med Econ. 2014 Jul 14:1-39. [Epub ahead of print]
Hosseini B, Flora DB, Banwell BL, et al.
Age of onset as a moderator of cognitive decline in pediatric-onset multiple sclerosis.
J Int Neuropsychol Soc. 2014 Jul 17:1-9. [Epub ahead of print]
Brownlee WJ, Miller DH.
Clinically isolated syndromes and the relationship to multiple sclerosis.
J Clin Neurosci. 2014 Jul 11. [Epub ahead of print]
Sandry J, Sumowski JF.
Working memory mediates the relationship between intellectual enrichment and long-term memory in multiple sclerosis: an exploratory analysis of cognitive reserve.
J Int Neuropsychol Soc. 2014 Jul 14:1-5. [Epub ahead of print]
Wilson L, Loucks A, Bui C, et al.
Patient centered decision making: Use of conjoint analysis to determine risk-benefit trade-offs for preference sensitive treatment choices.
J Neurol Sci. 2014 Jun 23. [Epub ahead of print]