A man from Poland paralyzed from the chest down, has regained feeling in his legs and is able to walk with the aid of parallel bars and leg braces, after nose cells were transplanted into his damaged spinal cord.
The man also reportedly can drive a car. Investigators say the former firefighter has recovered some bladder and bowel sensation, as well as some sexual function.
An international team of researchers is hailing as a "breakthrough" the success of the cell transplantation procedure.
They say the landmark procedure opens the door for others with damaged nervous systems who cannot walk due to spinal cord injury or stroke. But the operation is controversial.
The patient was paralyzed after being stabbed in the back in 2010.
Specialized olfactory ensheathing cells, taken from his nose, were transplanted after being grown in the laboratory. The cells are part of the sense of smell.
About 100 tiny injections of the cells were made above and below the severed spinal cord, which researchers bridged with nerve tissue across an 8-millimeter gap.
The lead researcher, Geoffrey Raisman of University College London’s Institute of Neurology, said the procedure clears the way for neural transplants to treat patients who can’t walk due to stroke and other neurological damage.
An estimated 3 million people around the world are confined to a wheelchair.
Simone di Giovanni, who did not participate in the research, is head of Restorative Neuroscience at Imperial College London.
Di Giovanni said the cell transplantation strategy is - in principle - very promising.
“But what is still unclear is how effective this strategy can really be for functional recovery, even in animals in pre-clinical studies. So, this poses further challenge to the interpretation of this one case," Di Giovanni said.
Di Giovanni said the experiments on animals have been under way for 30 years, with mixed results.
Experts said nerve cells in the spinal cord don’t regenerate. However, the olfactory bulb is a rich source of nerve cells that can be reproduced in a petri dish.
Di Giovanni remains cautious of the findings, reported by British and Polish researchers in the journal Cell Transplantation.
“I think it is a potentially interesting report. However, it is only a one-case report and as such, it is very, very difficult to draw a conclusion from that," Di Giovanni said.
Investigators do not want to give false hope to millions of paralyzed people around the world.
While they say the results are so far modest, investigators are planning clinical trials - with 10 more patients - involving a procedure they believe potentially could reverse paralysis.