Paralysis due to spinal injuries is a devastating injury that often leaves people in a wheelchair with no hope of being able to walk or use their legs again. Spinal cord injury currently affects over 200,000 people in the US and can be caused by a variety of traumatic instances.
(courtesy of http://www.cdc.gov/traumaticbraininjury/scifacts.html)
Science fiction has often fantasized about the possibilities of regenerative medicine and helping people with spinal injuries walk again, but this fantasy has not gotten us far, until now. Work by researchers in Poland have allowed a man, who suffered a traumatic spinal cord injury, to show improvement in his condition including improvements in muscle mass, sensations in the leg and voluntary movements. How were these scientists able to achieve such a remarkable and groundbreaking recovery? By using cells from the patients nose!
The cells isolated to treat the man in this study are called olfactory ensheathing glial cells. They are very similar to other glial cells in the nerves throughout your body (called Schwann cells) and are important in cleaning up damaged cells, clearing bacteria and in nerve regeneration in your olfactory system. Your olfactory system has the unique distinction of containing some of the only neurons in the body that can continually regenerate themselves throughout adulthood. This regeneration is thought to be assisted by these olfactory ensheathing cells and so make a logical target for possibly regenerating spinal cord nerves following injury.
The scientists isolated and grew these cells in a petri dish and then transplanted them into the spinal cord just above and just below the site of the injury. Once these cells were in place, they joined the two ends of the damaged nerve using another nerve from the leg of the patient. The patient then underwent an intense rehabilitation program (19 months) in order to try to facilitate the regeneration of the spinal cord. The results were fascinating. First, the patient suffered no loss of smell due to the removal of one of his olfactory bulbs suggesting that is was able to regenerate or the other bulbs were able to compensate. Secondly, the patient improved from having no movement or sensation in his legs (classified as ASIA A) to regaining some motor function and sensation in his legs (ASIA C). This meant the man could voluntarily move his legs (partially) and regained some of his lost muscle mass (following the rehab). Finally, when the scientists looked at images of the man’s spinal cord, it was confirmed that the nerve graft had bridged the injury.
The study is groundbreaking in its ability to apparently restore some function to the man’s legs and the relative ease of isolating cells to aid in the regeneration from the nose. Cautious optimism is necessary though for a couple reasons: 1) the man, contrary to how the media is representing it, is not walking around normally as he was before the injury. He has movement and sensation in his legs and is undergoing rehab (with the help of a walker and leg braces) to regain his muscle strength. It is too early to tell if this is as good as it will get or if he will continue to improve. 2) It is uncertain if the nerve graft will remain functional and living for an extended period of time. Currently, 19 months later, everything seems good. But follow up studies on the man are necessary. 3) This technique was done in one person and while it was seemingly successful, more controlled, clinical trials are needed to ensure that this is a viable treatment. It is important to note that the spinal injury in this man was relatively recent (21 months old) and so it is unknown if this treatment would benefit someone who has had their injury for a longer period of time. While there is undoubtedly more work to be done, the results are exciting and promising. People suffering from nerve injuries of all sorts may find relief and independence thanks to this therapy. Science fiction may become reality with help from your nose.