Wednesday, October 19, 2011

Advances in Using Stem Cells as a Treatment for MS


It is true that the term "stem cells" immediately has people thinking about those stem cells that are derived from fetuses or embryos – the topic of much discussion and controversy. However, much exciting work is being done on stem cells that can be taken from adults – either donors or the transplant recipient themselves.

Three presentations at ECTRIMS 2011 looked at current research on stem cells and the potential to be used as therapy for MS.

Until the late 1990s, stem cell research and theories around MS focused on only one thing – the idea that stem cells could be used to repair damaged cells that were no longer functioning. To date, researchers have not been able to produce damaged neurons with stem cells. However, about 10 years ago, it was discovered that stem cells can be used a different way – to create a "new" immune system for people with MS, one that does not attack the myelin.

The most progress in looking at the effect of stem cells in humans with MS (as opposed to experimental mice models) has been made on hematopoietic stem cells. This research was presented by Mark Freedman, MD from the Ottawa Hospital Research Institute at ECTRIMS 2011.

Hematopoietic stem cells (HSC) are taken from adult bone marrow and blood. They can also come from umbilical cord blood. They are multipotent, meaning they can turn into only a small number of different cell types. HSC are quite rare, making up less than .1% of bone marrow cells. These cells act as the foundation for the immune response.
Basically, the way that HSC can be used to treat MS are to "reconstitute" the immune system. The steps of treatment with HSC are:
  1. Bone marrow is harvested from the patient. 
  2. The HSCs are separated out from the other cells in the bone marrow. This is very important, as this also removes the pathogenic T cells that are thought to cause MS. 
  3. The HSC are multiplied in vitro (outside of the body). 
  4. Meanwhile, the patient's immune system is completely destroyed using chemotherapy. 
  5. The HSC are then transplanted back into the patient. 
  6. The HSC works to completely rebuild the immune system. However, the "new" immune system does not contain pathogenic T cells.
Dr. Freedman presented data from the Canadian MS Bone and Marrow Transplant study, which was conducted in 26 patients with very aggressive MS. These patients were on no therapy. Here is what happened:
  • None of the participants experienced relapses and no new lesions were detected.
  • Ten patients stabilized, meaning they showed no clinical progression, however they did not regain function.
  • Nine patients recovered much of their lost function. These were the ones who had been diagnosed most recently.
  • However, 7 patients continued to progress in terms of disability. Researchers think that timing of this kind of stem cell therapy is crucial and that to be effective, treatment cannot wait until there is too much damage.

The European Bone Marrow Transplant Registry is currently following people who got stem cell transplants in other places. It is estimated that about 50 people with MS are getting this kind of stem cell treatment every year.
  • A majority of these patients stabilized
  • Mortality started around 5 percent, but is now down to 1.3% of people treated this way.
  • People less than 40 years old and those who had the disease less than 5 years did best. 

The International Bone Marrow Transplant Study Group is initiating a clinical trial following this conference. This trial will randomize people to the best therapy in their country vs. HSC (bone marrow transplant). Look for exciting details about this study in upcoming months.


  1. I was just diagnosed in August. How can I get into a trial?

  2. This is a great article. Well-written and interesting.
    However, it is worth mentioning that the process mentioned above is very high risk. Destroying the existing immune system with chemo and then getting a bone marrow transplant by itself ends up killing a small, but significant % of patients. I can very well see how this approach may be appropriate in cases of very aggressive MS as those 26 mentioned in the trial, but more generally I am not sure it would be advisable for most MS patients.
    Another thing worth pointing out is that with an autologous transplant of this kind, since all the T cells are derived from the HSC, in the long run the patients may very well relapse since all their new T cells would come from their own HSC. I think one therefore cannot conclusively state that there would not be pathogenic T cells.
    Nonetheless this is an encouraging study.
    Paul Knoepfler
    Associate Professor
    UC Davis School of Medicine

  3. I'm 34 and was just diagnosed 4 weeks ago. How do I get on board?

  4. I received an autologous stem cell transplant for my aggressive MS last year as part of the NIH-supported Phase II clinical trial HALT-MS. As Dr. Knoepfler points out, HSCT is risky and in no way a guarantee. More research is critically needed and that's a huge problem: most health insurance companies (including my own, Presbyterian Health Plan) refuse to cover the treatment and the government doesn't have the money to pay for it.

    I made a video of my experience that won the Fan Favorite award in the AAN international film festival and I have started a both a Facebook page and website to encourage action. Phase III of this trial and others must happen if research is to advance.

    Dave Bexfield