A stem cell gel developed by scientists can regenerate broken spinal cord nerves, research has shown. The gel is applied to the site of an injury. In rats with completely severed spinal cords, it produced an "astonishing degree" of nerve growth, said US scientists. Treated animals which were previously paralysed experienced "significant" functional improvement and were able to move all the joints of their affected legs. The gel was made by embedding neural stem cells in a mixture of blood clotting protein and growth chemicals. "Using this method, after six weeks the number of axons (nerve fibres) emerging from the injury site exceeded by 200-fold what had ever been seen before," said study leader Professor Mark Tuszynski, from the University of California at San Diego. "The axons also grew 10 times the length of axons in any previous study, and, importantly, the regeneration of these axons resulted in significant functional improvement." Similar results were obtained in the laboratory using human stem cells. Cells were tagged with a fluorescent protein so that their progress could be monitored. Scientists watched them grow, become neurons, and sprout axons. | 
