New hope was raised yesterday for people left paralyzed by injury, after doctors said they had succeeded in using stem cells to restore feeling in two patients.
In a world first, doctors at Zurich University said two out of three men who had agreed to take part in an early trial, had regained some sensation below the level of their injuries.
It is the first time anyone has reported a positive outcome from stem cell therapy for severe spinal cord injury - and holds out the possibility of greater things in years to come.
The ultimate aim is to help those paralysed by injury to walk again.
Stem cells are special cells that can turn themselves into almost any kind of cell in the body. Those from human embryos have that absolute ability, while 'adult' stem cells have already specialized to a degree. For instance, neural stem cells can special ise into different type of nerve cells, but not something else like muscle or blood cells.
The trial worked on the theory that injected adult stem cells would transform themselves into spinal cord nerves, reconnecting brain and lower body.
Professor Armin Curt, leading the study, described the result as “fundamental”.
He said: “To find something that can repair the spinal cord is a huge breakthrough. If we can show that something has changed for the better [as a result of stem cell therapy] that’s fundamental.”
He presented the findings at the annual conference of the International Spinal Cord Society in London on Monday.
Prof Curt was working in partnership with StemCells Inc., a Californian company which also has a base in Cambridge.
Dr Stephen Huhn, from the firm, said: “We think these stem cells are one of the first tools we have for actually repairing the central nervous system.
"To see this kind of change in patients who truly have the worst-of-the-worst type of injury to the spinal cord is very exciting."
The three patients, who all had complete spinal injury where they could feel nothing below the break, were each given a dose of 20 million ‘adult’ neural stem cells about six months ago.
This was primarily a safety trial, and Prof Curt said monitoring had shown “a very good safety profile”.
But detailed questioning and objective tests also showed signals were passing up the injured spine to the brain, when they had not before.
One of the patients, Knut Ølstad, a 46-year-old Norwegian financial consultant, said: “I’ve noticed changes. When somebody touches my stomach, I can feel something. I can’t be specific, but I can sense it.”
Mr Ølstad was paralysed from the mid-chest down last summer during a cycling holiday in the Alps.
On his last descent, having cycled over 500 miles and climbed the equivalent of two Everests, he was flipped over the handlebars after braking to avoid a car.
The recent improvement was modest, but he said: “It provides me with hope for the future.”
He believed stem cells could one day help him and others like him walk again.
Prof Curt was cautious about that possibility, but Dr Huhn said: “I think it’s in the realm of possibility.”
Stem cell research for spinal injury “requires an incremental approach where we build the therapy one brick at a time”, he added.
Walking was not the only aim: people paralysed through injury also wanted to regain sensation, bowel and sexual function, he said.
The results come almost a year after another US firm, Geron, pulled out of a similar trial using embryonic stem cells, citing cost concerns.
