Stem cell transplantation holds the promise of recovery from debilitating spinal cord injury. Now, a paper in the March issue of Nature Neuroscience reports that the treatment can also worsen a problem suffered by some spinal cord injury patients.
In this condition, called allodynia, normally painless stimuli become painful. The authors showed that this side effect could be prevented by using gene transfer to control the type of cells produced from the transplanted stem cells.
Looking at recovery in rats with spinal cord injury, Christoph Hofstetter and his colleagues found that rats who received neural stem cells harvested from the spinal cord of other rats did recover some motor function as a result. However, they also developed allodynia in their forepaws, reacting to normal stimuli -- such as cold and pressure -- as if they were painful. This increased sensitivity was suggested to be due to abnormal axon growth in these animals.
Another group of animals received stem cells that had been infected with the gene for neurogenin2 before transplantation, which prevents them from differentiating into a type of brain cell called astrocytes. These rats showed even better recovery, without the allodynia and also had less abnormal axon growth.
These results show that stem cell transplantation may be useful in treating spinal cord injuries, but it can also cause serious side effects, which should be considered in the planning of human clinical trials.
Christoph P Hofstetter
Tel: +46 85 24 87 062
Additional contact for comment on paper:
Univ. of Wisconsin Medical School
Tel: +1 608 265 8668
Also available online.
(C) Nature Neuroscience press release.
Message posted by: Trevor M. D'Souza