| Spinal Cord Injruy Research at the McEwen Centre
Cellular Therapy
After a spinal cord injury, many of the nerve fibers at the injury site lose their insulating layer of myelin. As a result, the fibers are no longer able to properly transmit signals between the brain and the spinal cord contributing to paralysis. Unfortunately, the spinal cord lacks the ability to restore these lost myelin-forming cells after trauma.
- Research led by McEwen Investigator Dr. Michael Fehlings has shown that transplanting brain adult brain stem cells into the injured spinal cord helps recover coordination and improves walking patterns in experimental animal models of spinal cord injury. The transplanted cells traveled within the site of injury, came in close contact with neurons and developed into glia, a cell type which helps neurons function by forming an insulating sheet round them.
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Figure: After transplantation of adult neural stem cells into the injured spinal cord, grafted cells (green) are closely integrated into the injured spinal cord tissue especially around the surviving injured axons. Grafted myelin forming cells (green) ensheath the injured nerve fibers (blue) and restore myelin sheath (red) around them. Credit: Soheila Karimi and Eftekhar Eftekharpour (Fehlings Lab) |
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Research led by McEwen Investigator Dr. Freda Miller has shown that stem cells isolated from the skin of rodents and humans can make another type of peripheral myelinating cell called a Schwann cell. When transplanted into the injured rodent spinal cord, these stem cell-derived Schwann cells create a bridge across the spinal cord lesion. This bridge promotes the growth of neurons, and myelinates the regrowing neurons and uninjured neurons that have lost their myelin insulation, both changes that lead to improved locomotor function. These studies raise the possibility that such myelinating cells could ultimately be generated from the skin of spinal cord patients themselves, thereby alleviating problems associated with immune rejection.
Tissue engineering
Tissue engineering in the spinal cord involves the implantation of scaffold material to guide cell placement and foster cell development. These scaffolds can also be used to deliver stem cells at the site of injury and maximize their regenerative potential.
- McEwen Investigator Dr. Molly Shoichet is developing various three-dimensional scaffolds that are being tested in experimental models of spinal cord injury. Dr. Shoichet is designing scaffolds that provide support to replace lost tissue or to act as guidance channels for the neurons to regrow past the site of injury. Some may even provide a delivery system for growth factors or neuroprotective drugs.
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Figure: Primary neurons are guided to grow in hydrogel patterned with cell-adhesive peptides separated by non-adhesive volumes. Credit: Shoichet lab |
Figure: Minimally-invasive intrathecal drug delivery system for spinal cord injury repair.
Credit: Shoichet lab.
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Background: What is Spinal Cord Injury?
 When the spinal cord is damaged—either accidentally (car accidents, falls) or as the result of a disease (multiple sclerosis, infections, tumours, severe forms of spinal bifida, etc.)—it can result in the loss of sensation and mobility and even in complete paralysis.
Spinal cord injury has a profound impact on the lives of the individuals affected and their families. Unfortunately, when nerve cells in the spinal cord die, the damage is irreversible and currently cannot be cured. |
Impact of Spinal Cord Injury
41,000 Canadians live with spinal cord injury.
≥1,100 new spinal cord injuries occur each year.
84% of spinal cord injuries occur to people under the age of 34. |
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About Neurodegenerative Diseases
 Neurodegenerative diseases, such as Alzheimer’s disease, Parkinson’s disease, amyotrophic lateral sclerosis (ALS) and Huntington’s disease, are caused by the deterioration and death of brain cells, or neurons.
Depending on the type of neurons affected, neurodegenerative diseases may impact various brain functions, such as movement (as in Parkinson’s disease and ALS) or memory and cognition (as in Alzheimer’s disease).
For many years scientists thought that the brain was incapable of producing new cells in adulthood. We now know this is false, but the brain’s capacity to replace dying neurons is very limited. People with neurodegenerative disease currently face a future without hope of a cure.
As the Canadian population ages, the number of individuals living with neurodegenerative disease is expected to continue to grow. |
Impact of Neurodegenerative Diseases
420,000 Canadians over the age of 65 have Alzheimer Disease or a related dementia (Alzheimer Society of Canada)
100,000 Canadians live with Parkinson’s disease (Parkinson Society Canada)
3,000 individuals in Canada live with ALS (ALS Society of Canada) |
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