Possible benefits of Stem Cell Transplantation for stroke

There in an increasing amount of research showing that stem cell transplantation can help stroke survivors. For example, scientists at the Stanford Stroke Center injected stem cells into the brains of rats who had suffered a stroke. Their tests showed that the stem cells did move to the damaged areas when they were injected close to the injury. They also found that the stem cells turned into the correct type of cell to make repairs and restore function.³ Another advance, outlined in a press release, offers more evidence that stem cells can repair brain damage after a stroke. A team of researchers at King's College London developed a tiny scaffolding that supports stem cells. They injected it into the brains of rats and found that ‘it is possible to fill a hole left by stroke damage with brand new brain tissue within 7 days.’⁴

In 2010, Professor Keith Muir and his research team began a clinical trial called the Pilot Investigation of Stem Cells in Stroke (PISCES). This is the first official trial to inject stem cells directly into the brains of ischemic stroke survivors. The trial aims to treat 12 patients by injecting them with between 5 million and 20 million stem cells. The PISCES trial began by injecting the brain of an elderly stroke survivor with a low dose of ReN00, which comes from foetal brain cells. The research team will follow his progress over two years. They intend to repeat this procedure with 11 more stroke survivors. Each patient will be given a higher dose. Researchers will then monitor any improvements in their condition and assess the safety of the treatment. If the first phase of this trial is successful, it is likely that it will be followed by a second, larger trial.⁵ The PISCES trial is being carried out in conjunction with ReNeuron Group plc. The chief scientific officer at ReNeuron, the company that developed the cells, explains that animal trials have already shown a good deal of success using similar methods:

‘We see re-growth of blood vessels, the generation of new neurons, a reduction in scarring and inflammation in the brain …There are a range of things that happen that are best described as the brain to some extent healing itself.’⁶

In 2009, Roland "Bud" Henrich became the first stroke patient to be injected intravenously with his own stem cells as part of a research trial. Doctors farmed the stem cells from his bone marrow. Henrich had suffered a stroke several months prior to the treatment. He had lost his ability to speak and suffered from significant weakness on his right side. Since the treatment, Henrich is able to walk and climb the stairs unaided and his speech is starting to return.⁷

There are also thousands of unverifiable stories of people who claim great success with stem cell treatment obtained through private clinics. In some countries, these clinics are licenced and regulated; in others, they are not. The following is a typical example of a reported case: Keith Buller, 57 years old, had a stroke that left him in a wheelchair and without speech. Nearly nine years later he received stem cell treatment at a clinic in Germany. The following is his own account:

‘Around 6 weeks after the stem cells were re-implanted into my spinal fluid, I woke up one fine day without any ear pain. I had lived with constant dull ear pain for over nine years and the pain had just disappeared! My face didn’t sag so much either. I could control my facial muscles much better and I could speak much better, too. I was finally able to have a conversation again. I had also had no sensation in my paralyzed right arm for those 9 years. All of a sudden the arm started to itch, it itched for literally 2 weeks and then suddenly the feeling returned. I could open and close my hand halfway much more easily. I’d also suffered from some pretty serious pain in my right leg below the knee; the pain has diminished and the only remaining pain is in the right ankle.'⁸

Arguments against Stem Cell Transplantation for stroke

Changes in legislation have led to human clinical trials in the UK and USA since 2009.⁹ Despite this, stem cell transplantation is not accepted by large sections of the medical community. Many doctors believe it is a potential treatment for stroke but is not yet ready to use. They argue that people who are desperate for a 'cure' are prepared to try anything. Stem cell treatment has been compared to 'snake oil', a tonic that makes great claims but is not backed up by sound medical evidence. Their suspicion is fuelled by the fact that many of the clinics are 'offshore'. For example, one clinic that treats patients from the USA is in the Dominican Republic.

Another argument against stem cell transplantation is based on the use of human embryo or foetal stem cells. Some clinics do use these stem cells, but not all. It is no longer necessary to harvest stem cells from a foetus. Stem cell treatment clinics increasingly use ‘adult stem cells’, which come from your own body. It is also possible to use cells from umbilical cord blood and possibly even from animals. Recent research has also been conducted into taking cells from teeth. The main benefit of stem cells from teeth is that they can be easily extracted and do not pose rejection issues for patients.¹⁰

The high cost of stem cell treatment at private clinics has also raised suspicion. On average, the cost of one treatment falls between €7,500 and €35,000. Add to this the cost of travelling to places such as Ukraine or China, where you might also have to pay for accommodation because most of the clinics are not residential.

Some researchers who support stem cell therapy believe that it will not help every stroke survivor. For example, it might be more difficult to treat brain infarcts involving white matter, which contains myelinated nerve fibres.¹¹

Stem cell treatment is an issue that is legally complex and religiously and politically controversial. As a consequence, there can be sudden changes in regulatory policies.¹² This can lead to discontinuation of treatments offered in some clinics or countries, which could result in cancelled appointments. For example, the German authorities recently passed new legislation that resulted in the closure of the controversial X-Cell Centre at the Institute for Regenerative Medicine, the largest stem cell clinic in Europe.¹³

Case histories

1. This article outlines an element of the stem cell debate and the experiences of Chuck Melton, a burly 24-year-old factory worker who went to China for stem cell therapy.

2. This BBC news article tells the story of three-year-old Dakota Clarke. She was born with a rare condition that affected her vision and balance. Stem cell treatment has helped her to “see things that she could not see before”. BBC News Saturday, 16 May 2009 00:29UK

Notes and references

1. ‘The leading edge of stem cell therapeutics’ by Singec I, Jandial R, Crain A, Nikkhah G and Snyder EY. In Annu. Rev. Med. 58: 313-328, 2007
2. ‘Stem cells for ischemic brain injury: a critical review’ by Burns TC, Verfaillie CM, Low WC. In J Comp Neurol. 2009 Jul 1;515(1):125-44. Review.
3. 'Long-term monitoring of transplanted human neural stem cells in developmental and pathological contexts with MRI’ by Raphael Guzman, Nobuko Uchida, Tonya M. Bliss, Dongping He, Karen K. Christopherson, et al. Edited by Irving L. Weissman, Stanford University School of Medicine, Stanford, CA, and approved April 24, 2007 (received for review October 6, 2006)
4. ‘Stem cells could help treat strokes’, BBSRC Press Release, Institute of Psychiatry, News, March 2009
5. 'Stroke patients take part in "milestone" UK trial of stem cell therapy'. Wise J. In British Medical Journal 2010; 341:c6574
6. ‘Stem cells injected into the brain of a stroke patient in world first’ by Ian Sample. guardian.co.uk, Tuesday 16 November 2010 13.03 GMT. The Principal Investigator for the PISCES (Pilot Investigation of Stem Cells in Stroke) trial is Professor Keith Muir, SINAPSE Chair of Clinical Imaging, University of Glasgow. It is a joint study between University of Glasgow and the ReNeuron Group, which on its webpage describe itself as a ‘clinical-stage stem cell business’. See: ReNeuron
7. 'Stem Cells Tested for Treatment of Stroke’ by Deborah Mann Lake. In Texas Medical Center: Issue Date: July 1, 2009.
8. XCell-Center, Germany. Mr. L. Ludemann
9. A human clinical trial to investigate the benefits of stem cells for stroke survivors was approved in Scotland in January 2009: ‘Restorative therapy in stroke using stem cells’ by Padma Srivastava MV. In Neurol India 2009 57:381-6. Nov. 2009. In early 2010, the Gene Therapy Advisory Committee in the UK gave ReNeuron permission to launch a human trial on the effects of stem cell therapy after a stroke. In May 2009, President Barack Obama decided to allow human stem cell research in the USA. This began with a clinical trial on the effects of stem cell therapy on spinal cord injury: ‘A New Stem Cell Era’ by Claudia Kalb. Newsweek, 9 March 2009.
10. ‘Stem cell research gives hope to stroke patients’. Psy-Org.com, December 8th, 2009
11. ‘Study on stem cells for stroke patients to start in Scotland later in 2009’ by Bryan Christie. In BMJ 2009;338:b245.
12. Elstner A, Damaschun A, Kurtz A, Stacey G, Aran B, Veiga A, Borstlap J “The changing landscape of European and international regulation on embryonic stem cell research” Stem Cell Research, 2009(2), 101–107.
13. Since December 2008 Regulation 1394/2007/EC has been in effect in the European Union. National or community legislation on stem cell research must conform to this legislation by December 2012. For a summary of 1394/2007/EC in the context of German medical legislation please klick here.