Most cells in the body have the capacity to repair and renew. If you injure your skin, you will usually heal. However muscle and nerve cells are unable to repair and replace themselves. This is why if you have a heart attack there is death of cardiac muscle cells and new cells cannot replace the dead ones and if the spinal cord is severed nerve cells cannot repair. However there is an exception to this rule. Professor Raisman at UCL showed that olfactory bulbs in the brain contain nerve cells that do renew themselves. Chemicals in the air constantly hit these nerve cells and damage them. They regenerate because olfactory ensheathing cells [OECs] provide a pathway for fibres to grow back.
Professor Raisman demonstrated that paralysis in rats could be by these cells and now he has achieved some success with a patient.
Dr Pawel Tabakow heads the Polish team of scientists in Wroclaw responsible for making the leap from animal research to humans. He managed to get ethical approval to perform brain surgery and remove these olfactory nerve cells and then do a second operation on the spinal cord and inject these cells into it, on a patient, Darek Fidyka. His spinal cord had been cleanly cut, rather than crushed, by a stab wound.
The scientists believe the OECs provided a pathway to enable fibres above and below the injury to reconnect, using the nerve grafts to bridge the gap in the cord. Mr Fidyka had intensive physiotherapy five hours a day for five days a week and about 3 months after surgery started to notice improvements. He can now walk using a frame and some sensation has returned.
This has to be repeated in other patients before we can say that this is a definite treatment for spinal cord injuries. Mr Fidyka had a clean cut of his spinal cord however most spinal injuries are crush injuries. These would be much harder to treat by this method.