Researchers continue to make progress in induced nerve regeneration: "researchers were able to regenerate 'an astonishing degree' of axonal growth at the site of severe spinal cord injury in rats. Their research revealed that early stage neurons have the ability to survive and extend axons to form new, functional neuronal relays across an injury site in the adult central nervous system (CNS). The study also proved that at least some types of adult CNS axons can overcome a normally inhibitory growth environment to grow over long distances. Importantly, stem cells across species exhibit these properties. ... The scientists embedded neural stem cells in a matrix of fibrin [mixed] with growth factors to form a gel. The gel was then applied to the injury site in rats with completely severed spinal cords. ... Using this method, after six weeks, the number of axons emerging from the injury site exceeded by 200-fold what had ever been seen before. 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. ... The grafting procedure resulted in significant functional improvement: On a 21-point walking scale, without treatment, the rats score was only 1.5; following the stem cell therapy, it rose to 7 - a score reflecting the animals' ability to move all joints of affected legs. Results were then replicated using two human stem cell lines, one already in human trials for ALS. ... We obtained the exact results using human cells as we had in the rat cells."