Researchers are said to be “stunned” by the success of a recent clinical trial of a new stem cell treatment for stroke patients. By injecting the cells into participants’ brains, scientists were able to produce some remarkable improvements, with several patients regaining motor function in their limbs.
A full report of the study has been published in the journal
Stroke , with lead author Gary Steinberg telling the Washington Post that patients’ improvements were “not just minimal recovery like someone who couldn't move a thumb now being able to wiggle it. It was much more meaningful. One 71-year-old wheelchair-bound patient was walking again.”
The trial involved the use of modified bone marrow–derived mesenchymal stem cells, which were injected into the specific region of each patient’s brain that had become damaged following their stroke. Amazingly, the researchers were not actually expecting to see any clinically relevant results at this stage, as they were just testing out a low dose of the treatment in order to assess its safety.
However, of the 18 patients involved in the study, seven experienced dramatic improvements in their cognitive and motor capabilities. In terms of safety, the study authors report that all participants experienced at least one temporary adverse effect, ranging from headaches and nausea to muscle spasticity. Importantly, though, all of these are thought to have been caused by the surgical procedure itself rather than the stem cells.
How stem cell treatment can restore motor function for stroke patients

To evaluate the success of the treatment, the researchers used a number of standardized scales that are commonly used to assess the severity of symptoms in stroke patients. For instance, the Fugl-Meyer motor function total score is often used to measure recovery, with an improvement of 10 points representing a “clinically meaningful” change.
The patients involved in the study experienced an average improvement of 11.4 points on this scale, which translated into a “clinical improvement in the power of upper and lower limbs, ranging from an improvement in the ability to stand to the disappearance of tremor.”
Furthermore, the study authors make a point of noting that their patients had been suffering from their various symptoms for an average of 22 months prior to treatment. This is well beyond the six-month cut-off period that is typically considered to represent the point at which stroke-related brain damage becomes permanent and untreatable.
Exactly how the treatment works is not entirely understood, although Steinberg suspects that the stem cells somehow kick-start the brain's own ability to repair itself, rather than developing into new neurons themselves.
Given that at present, more than 70 percent of people who suffer strokes end up with some sort of enduring disability, this new treatment could potentially be a game-changer – although more trials will be needed before it becomes readily available.