From the Guardian, a look at a research group that is attempting to use cells from the nose to regenerate presently untreatable nerve damage: "Studies in animals have established that the cell implants can restore nerve functions. Rats with severed nerves have regained functions of a forepaw. But the first human study, which tests the safety of the procedure, will be limited to patients with one very specific and similar injury to ensure the results are clear. ... If successful, with refinement and research the procedure could be tried on people in a wheelchair. It also has the potential to heal other nerve injuries, such as those caused by stroke, blindness and deafness."
Link: http://www.guardian.co.uk/medicine/story/0,11381,1653838,00.html