Stem cell hope for Duchenne muscular dystrophy

Duchenne muscular dystrophy (DMD) is an inherited disease that affects about one in every 4,000 males born in the USA. It is caused by mutations in the DMD gene that lead to the protein dystrophin being either absent or faulty, which leads to muscle cell death, progressive muscle wasting and early death, with few patients surviving beyond their 40th birthday.

In recent years scientists have been investigating the possibility of transplanting healthy stem cells into the muscle of patients in order to replace the lost muscle cells and halt the progression of the disease, but it has proved difficult to identify muscle precursor cells that can both make new muscle cells and persist as a pool of precursor cells in the patient, the latter is an important consideration if repeated transplants are to be avoided since muscle cells wear out and need to be replaced.  A paper published in this weeks issue of the scientific journal Cell by scientists at Harvard University is an important step towards developing a means to screen for the right cells and use them to treat DMD

http://news.bbc.co.uk/1/hi/health/7500523.stm

In their work (1) Dr. Amy Wagers and her coworkers concentrated on a type of cell known as satellite cells that are closely associated with muscle fibers in mice and humans; by studying the proteins found on the surface of these cells they were able to identify a sub-population they termed skeletal-muscle precursor cells (SMPs)  in mice that could produce muscle cells while maintaining a reserve of precursor cells for future rounds of muscle cell production.  They next needed to evaluate these cells for their ability to do this when transplanted into an animal whose muscles were being damaged due to faulty dystrophin, in order to determine whether their ideas were correct.
They chose to use the mdx mouse model, a mouse which has a defect in the dystrophin gene and displays many of the biochemical and physiological characteristics of DMD. The mdx mouse displays less severe symptoms than humans with DMD, but like humans is characterized by progressive muscle wasting and early death and has been crucial to the development of many of the new therapies for DMD, including gene therapy and novel drugs, that are currently entering clinical trials. Dr. Wager’s work found that engraftment of transplanted SMPs into the muscles of  mdx animals lead to the production of new muscle cells to replace lost to DMD, and that the transplants also showed therapeutic value by improving muscle histology and rescuing physiological muscle function i.e. the muscles got stronger.  Analysis of the muscles of mice which received transplanted cells also showed that the second requirement that the transplanted cells should give rise to a pool of cells capable of acting as a source of muscle cells in future was also fulfilled.

This is very promising work, and marks an important milestone in the development of stem cell therapy for DMD.  Before human trials can begin however more work will need to be done to develop methods of isolating and preparing human SMPs for use in clinical trials, and there remains the challenge of how to transplant the cells into all the muscles in the body where they are required.

Cheers

Paul Browne

Related posts:

Progress towards a cure for Duchenne Muscular Dystrophy

Promising clinical trial result for exon skipping in Duchenne Muscular Dystrophy

1) Cerletti M. et al. “Highly Efficient, Functional Engraftment of Skeletal Muscle Stem Cells in Dystrophic Muscles” Cell Vol 134, Pages 37-47 ( 2008)

10 responses to “Stem cell hope for Duchenne muscular dystrophy

  1. l have Duchenne Muscular Dystrophy & l am happy that something is being done to end this disease. I hope l will be still alive when the first cure will be discovered or invented .

  2. Amit,
    Exon skipping is a promising research it seems but then that is for DMD. You have not mentioned whether you are looking for DMD or some other muscular dystrophy. Also, which are the exons deleted? Exon 51 skipping is at most advanced stages of research.
    Rgds….Anup

  3. There is a huge amount of research coming through, but it often takes years for it to actually reach the markets – something scientists and regulators are trying to speed up.

  4. Is there any recent research going on muscular destrophy. Is there any treatment till now. Please send the reply quickly.

  5. Jyotirmai, I am not a medical doctor so I can’t offer any specific advice, but I do encourage you to discuss the possibility of your son taking part in clinical trials of new treatments with your son’s doctors.

    They can advise you on whether there are any clinical trials in progress or being planned that your son could take part in.

    You might find the following websites helpful, and they may be able to tell you about clinical trials that are being planned.

    http://www.muscular-dystrophy.org/
    http://www.mdausa.org/

    I hope that your efforts on behalf of your son are successful.

    • Hi,

      My son is 5 years old is just now diagnosed with DMD. He is ok right now. Have approached for enrolling him for clinical trials with researhers and pharmaceutical companies. Will highly appreciate your guidance in this regard.
      Regards…Anup

      • Blue Sky Science

        I’m sorry to hear about your son’s DMD, and admire your decision to see if he can take part in a DMD therapy trial, such trials make a vital contribution to the development of medicines which may benefit not only your own son but thousands of other people with muscular dystrophy. I’m not qualified to give professional advice on participation in clinical trials, but it is clearly important to ensure that any trial your son participates in is appropriate for him.

        The UK Muscular Dystrophy Campaign has some good general advice at:

        http://www.muscular-dystrophy.org/research/your_questions_answered

        The US National Institutes of Health (NIH) has some information, with links to useful resources on clinical trials at:

        http://www.ninds.nih.gov/disorders/md/md.htm#Clinical_trials

        A good place to start is the ClinicalTrials.gov website, which lists all clinical trials that have been registered in the US, and many in other countries, I searched using the keywords “muscular dystrophy” and limited my search to active trials, and found 47 trials which are either recruiting patients or will soon start to do so.

        http://clinicaltrials.gov/ct2/results?term=Muscular+Dystrophy&recr=Open&rslt=&type=&cond=&intr=&outc=&lead=&spons=&id=&state1=&cntry1=&state2=&cntry2=&state3=&cntry3=&locn=&gndr=&rcv_s=&rcv_e=&lup_s=&lup_e=

        At the risk of stating the obvious, I would also add that before taking part in a trial you should discuss the trial thoroughly with your son’s consultant, and make sure that all relevant medical records are available for the clinical trial team to examine. Make sure that you find out from the clinical trial team who will be responsible for any longer-term follow up care that your son after the trial has officially finished, and how participation in the trial will affect medical insurance cover.

        Finally, I would urge you to be very cautious about any clinical trial where you are expected to pay for the cost of the procedure, or for a substantial part of the costs, such charges are often a sign that the trail is not a genuine trial but rather a cover for unscrupulous doctors who want to make money from an procedure which has not yet been shown to work.

        I hope this information is useful, and hope that you find a treatment that helps your son.

  6. My 7 year old son is suffering from dmd.I come to know about 4 years before, In begining he didnot climb but walk run easily. But from 3 month before he is unable to stand now he cannot sit self. In dystrophin gene test a deleation of number 12 is told.I want to know any stem cell therepy or medicine can cure him.Thanks.

  7. Sarona Stanley

    My son was diagnosed with DMD early 2005. He has been wheelchair-bound since. He was 8 years old when he was diagnosed with DMD. He is now 12 years old and the rapid muscle wasting has worsened in the last 3mths. His eyesight has also gone bad in the last 6 months. I wish and pray that the medical profession would come up with some form of stem cell treatment soon for DMD like they did with the 19-year old with Multiple Scloresis earlier today. The Announcement has given all DMD sufferers hope. May our good Lord above continue to guide the medical profession in expediting the process of stem cell treatments for all DMD sufferers including my precious son. Please help make my son live.