Spinal cord injury can lead to severe motor, sensory and autonomic dysfunction. Currently, there is no effective treatment for the injured spinal cord. The transplantation of Schwann cells, neural stem cells or progenitor cells, olfactory ensheathing cells, oligodendrocyte precursor cells and mesenchymal stem cells has been investigated as potential therapies for spinal cord injury. However, little is known about the mechanisms through which these individual cell types promote repair and functional improvements. The five most commonly proposed mechanisms include neuroprotection, immunomodulation, axon regeneration, neuronal relay formation and myelin regeneration. A better understanding of the mechanisms whereby these cells promote functional improvements, as well as an appreciation of the obstacles in implementing these therapies and effectively modeling spinal cord injury, will be important to make cell transplantation a viable clinical option and may lead to the development of more targeted therapies.
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P.A. received a Canadian Institute for Health Research (CIHR) Frederick Banting and Charles Best Canadian Graduate Scholarship–Doctoral Award and the CIHR Transplantation Training Program Award. G.J.D. was supported by a Multiple Sclerosis Society of Canada Doctoral Scholarship and the CIHR Transplantation Training Program Award. B.J.H. holds a CIHR Frederick Banting and Charles Best Canadian Graduate Scholarship–Doctoral Award, a Zoology Graduate Fellowship and a CIHR Transplantation Training Program Award. J.R.P. is supported by the Donna Joan Oxford Postdoctoral Fellowship Award from the Multiple Sclerosis Society of Canada and by postdoctoral fellowship awards from CIHR, Alberta Innovates Health Solutions and T. Chen Fong. W.T. receives support from the John and Penny Ryan British Columbia Leadership Chair in Spinal Cord Research and from CIHR FRN 130475.
The authors declare no competing financial interests.
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Assinck, P., Duncan, G., Hilton, B. et al. Cell transplantation therapy for spinal cord injury. Nat Neurosci 20, 637–647 (2017). https://doi.org/10.1038/nn.4541
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