Scientists at NUI Galway are starting tests on the use of stem cells to treat spinal cord injury. Michelle McDonagh meets the head of the research
Spinal cord injury affects more than 25 million people worldwide, with 130,000 new cases reported each year. Professor of neurology at the Mayo Clinic in Minnesota, Anthony Windebank, believes the difficulties associated with spinal cord repair may be solved within the next 10 years, but he urges caution when discussing possible "cures" for such a life-shattering injury.
Windebank leads a research alliance which involves the Regenerative Medicine Institute (Remedi) at NUI Galway and the Mayo Clinic. The research combines adult stem cell expertise at Remedi with a novel tissue engineering breakthrough pioneered at the Mayo Clinic.
Up to 80 per cent of spinal cord injuries (SPIs) in Europe and the US occur in the under-40 age group. The main causes of the injury in Ireland are road traffic accidents, sports accidents and general accidents such as falls. The overwhelming majority of victims tend to be male.
"Because it is such a disease of young people, most people with spinal cord injury live for many years afterwards, so the injury burden for the person, their family and society is huge," says Windebank.
About half of all SPIs occur in the lower part of the spinal cord, the lumbar region, causing paraplegia, which involves the loss of the use of the legs. The other half strike at the level of the neck, causing quadriplegia, the loss of the use of the arms and legs. A very high spinal cord injury can also affect breathing.
While use of a wheelchair is the most obvious result of a spinal cord injury, almost all patients lose control of their bowel and bladder function and of their sexual function. Many will suffer pain and muscle spasms.
"If you ask people with SPI what they would like to get back most, people with lower back injury want control of their bowel and bladder back, even above being able to walk again.
The majority of people who are paralysed end up living independent lives in wheelchairs, he says, with 70 per cent in Ireland going back to some form of work. However, for a quadriplegic, the chances of going back to work are low and most are never able to live independently.
Not surprisingly, depression is a major problem in spinal cord injury patients, but the extent of this problem depends to some extent on the quality of the rehabilitation available to them. "In Ireland, people are lucky. All spinal cord injury patients end up at the Rehabilitation Institute in DúLaoghaire, which is comparable to such facilities anywhere else in the world," he says.
While Windebank stresses that hope of a cure should not be promoted by the scientific community, he says spinal cord injury victims may have legitimate reason to believe that treatments are closer than ever.
He urges people to be wary of the "amazing" new stem cell treatments which are available in places such as Mexico and eastern Europe. "If people read about these treatments and wonder whether they should travel abroad, they should first check to see if there is a lot of money being charged. If it's a reputable research study in Europe, the US, Canada, Australia or any developed country, they do not allow charges for experimental treatments. You must be very certain that the treatment will not cause you any harm . . . One of the major concerns is that unregulated stem cell treatment, whether adult or embryonic cells, might cause some unusual forms of cancer."
The research that Remedi and the Mayo Clinic are working on is already showing encouraging results in spinal cord injury repair in animals. The concept of using synthetic materials in the body is not new; artificial joints have been used for the past 50 years. What is new is the idea of using these materials as a form of scaffolding for stem cells. Stem cells are cells that have the capacity to develop into any organism in the body - organ, muscle, cartilage, fat or nerve.
The Remedi study is using only adult stem cells, which can be obtained from the bone marrow of the patient, and not the more controversial embryonic cells. "The advantage of using adult cells is that you are using the person's own tissue to repair their own tissue. The disadvantage is that adult stem cells are harder to make behave the way we want them to," says Windebank.
"It's hugely challenging, but now we have the tools and, with time, it is realistic to believe that we will be able to get the nerves to reconnect and refunction again in humans. If a nerve in the peripheral nervous system, such as in the arm or the leg is cut, it will actually regenerate quite well by itself and reattach to the muscle. These are the exact same nerves as the spinal cord, just in a different environment. What we are doing is trying to provide an environment for the nerves to regenerate in the spinal cord."
The first pre-clinical trials at Remedi using neural stem cells have just been announced. Initial results are expected in the first quarter of 2007. "I would be hopeful that a person who sustained a spinal injury this year could expect that within seven-10 years we will have made progress," he adds optimistically.