Stem cell research for spinal cord injuries covers wide territory. Some researchers focus their attention on using the stem cell research for spinal cords to create new myelin sheath cells and others simply want to improve the quality of the patients life regardless of the process. While most of the studies such as these are on lab rats, rather than human patients, a study using autologous stem bone marrow derived stem cells on human victims of spinal cord injury showed an improvement in the quality of life of the victims.
Reeve-Irvine Research Center
In Irvine, California at the Reeve-Irvine Research Center, University of California, Hans Keirstead and a group of colleagues used rats to study the effects of human embryonic stem cell treatment to restore motor skills they lost when they suffered acute damage to the spinal cord tissue. Their focus was on the restoration of the myelin sheath.
They myelin sheath is insulation tissue for neurons and mandatory for the conduction of electrical messages through the nervous system. If you look at the nerves as being similar to an extension cord and the spinal cord as the one that plugs directly into the outlet, when spinal cord injury occurs, it’s similar to slicing away some of the outside insulation on an electrical cord. The electricity never reaches the fixture that needs it for energy. In the case of the spinal column and myelin, the message from the brain to the extremities is lost at the site of the missing myelin.
Working from that information, the team at UC Irvine concluded that if you focused on repairing the sheath, you would restore lost neurological function. Earlier studies by the group showed the body’s own immune stem attacked the myelin and destroyed it after injury to the spinal cord. Initial studies showed that if they used antibodies suppressing that response, the myelin could regenerate and therefore restore the lost functions.
The team at UCI then used a method to encourage the stem cells to develop into oigodendrocyte cells, which are the building blocks necessary for the formation of myelin. In rats given the treatment with stem cells for spinal cord injury, within 7 days after injury, the cells did for the myelin tissue and wrap around the area of damage. After just two months, these injured rats walked. Their counterparts that received no treatment did not.
The scientists wondered whether this treatment could help previously injured victims. They injected the cells into a group of rats 10 months after injury. While the early-stage cells formed mature oligodendrocyte cells in both groups and traveled to the spinal cord, they could not grow because scar tissue filled the neuron cells and inhibited the myelin growth.
Karolinska Institutet
Karolinska Institutet, Stockholm Sweden, had similar results. However, they found that there were some problems with the use of stem cells for spinal cord injury. While it restored function, it also increased pain sensitivity in the rats. In order to avoid this, the scientists used a special gene in the stem cells, neurogenin-2 when they developed them in the culture. The hypothesis on the increased pain was that some of the cells developed in to a type of glial cell called astrocytes. These cells tend to cause pain axons to grow in the spinal cord with the secretion of substances that stimulate the development of neuronal cells.
The group also noted that the increased number of oligondendrocyte cells produced by the neurogenin-2 stem carrying stem cells, corresponded to a higher amount of myelin-coated nerves, white material, in the area of the damage.
The team at Karolinska Institutet used fMRI, functional Magnetic Resonance Imaging, to demonstrate the restoration of the sensory function. This technique, use at the institute’s experimental MRI location has an advantage. If experiments start on humans, the fMRI is one method of comparing results in the human studies.
Krembil Neuroscience Center
The work at the Krembil Neuroscience Center in Toronto Western Research Institute and the University of Toronto also noted that there was a window critical to the effectiveness of stem cell transplants. They added a combination of immune suppressing drugs and growth factors into the therapy and transplanted stem cells from the brains of adult rats into the crushed spines of injured rats. Over a third of the cells traveled to the area of injury and created tissues like those destroyed at the area, including myelin. As with the California study, the Toronto study showed that the process worked best soon after the injury and failed to work if done too late in the healing process.
Another study called “Activated Spinal Cord Ependymal Stem Cells Rescue Neurological Function” published by Moreno-Manzano, V., Rodríguez-Jiménez, F. J., García-Roselló, M., Laínez, S., Erceg, S., Calvo, M. T., Ronaghi, M., Lloret, M., Planells-Cases, R., Sánchez-Puelles, J. M. and Stojkovic, M. in 2009, shows the stem cells in the spinal cord lining called ependymal stem cells, reverses paralysis that often occurs with spinal cord injury. These cells are multiples higher in those with a spinal cord injury than with healthy subjects.
Once the transplant subject formed a lesion, the use of stem cells was more effective at creating the types of cells necessary for the repair of the area. While the study was an animal study, the information gleaned can help scientist understand the working mechanisms of stem cells and better ways to use them for human spinal cord damage.
DaVinci Biosciences did a cooperative study with Luis Vernaza Hospital in Ecuador showing that therapies using autologous bone marrow derived stem cells, stem cells that later form blood cells removed from the person whom they later benefit, are safe and improve the quality of life of victims who have chronic and acute spinal cord injury.
The study was small. It included only eight people, four with chronic injury and four with acute injuries. The study used several methods to test the quality of life, pain and improvement. The treatment showed no increase in pain and yet showed improvement to the quality of life that ranged from increased sensations to better mobility and bladder control. While the degree of improvement varied in patients, all eight subjects had some improvement.