A paralyzed man is now able to stand on his own after receiving an injection of reprogrammed stem cells into his spinal cord injury. In a first-of-its-kind trial run by neuroscientist Hideyuki Okano and his colleagues at Keio University, four men, all classified as having no motor or sensory function below the injury site, received transplantations of cells derived from induced pluripotent stem (iPS). Two of them saw improvements in their motor functions. As well as the man who was able to stand, another also regained some movement and was able to eat by himself. The two others, however, experienced minimal improvement.
The ASIA Impairment Scale
Spinal cord injuries are ranked on a five-level scale known as the American Spinal Injury Association (ASIA) Impairment Scale, or AIS. The most severe grade is A, which is complete paralysis. Grade B occurs when the person has some sensation below the point of injury but a loss of motor function. At grade C, the key muscles are not strong enough to move against gravity, whereas they can at grade D. Grade E patients’ functions are normal. The motor functions of one of the patients in the trial improved from grade A to D.
“That person is now training to walk. This is a dramatic recovery,” said Okano. Toru Ogata, a professor at the University of Tokyo, who is well-versed in spinal cord injuries, added, “It’s possible that the [transplanted] cells have engrafted and are increasing the number of nerves. Even though it is only one person, it’s amazing that a grade-A patient is now able to stand and can start practicing to walk. The outcome is groundbreaking.”
No Serious Adverse Health Effects Observed
All four patients were two to four weeks out from suffering a spinal cord injury. Two of them were aged 60 or over. Other details about them remain confidential. The surgeries were performed between 2021 and 2023. The main aim of the trial was to confirm the safety of injecting the cells. Fortunately, no serious adverse health effects were observed. Further trials on patients with chronic paralysis are expected in 2027.
