Rats once paralyzed from complete surgical cuts through their spinal cords can walk again after stem cells were transplanted into the site of the injury, report researchers today in the journal Cell. The results suggest that stem cells might work as a treatment for patients even if they have completely severed cords, a potential therapy that has been viewed skeptically by many in the field.
Neural stem cells, derived from aborted fetal spinal cord tissue, were implanted onto each side of the spinal cord injury in the rats along with a supportive matrix and molecular growth factors. The human stem cells grew into the site of injury and extended delicate cellular projections called axons into the rats spinal cord, despite the known growth-inhibiting environment of the injured spinal cord. The rats' own neurons sent axons into the transplanted material and the rats were able to move all joints of their hind legs.
The cells are produced by a Rockville, Maryland company called Neuralstem. The same cells are also being tested in ALS patients (see "New Cells for ALS Patients") where they have shown some promise of stabilizing the progressive disease. Last month, the company announced that it has asked to FDA to approve a trial to test the cells in spinal cord-injured patients.