Abstract:

In our recently co-authored Physiological Reviews manuscript entitled “The biology of regeneration failure and success after spinal cord injury” , we sought to provide a comprehensive and up-to-date description of how the glial scar develops following spinal cord injury (SCI) to chronically inhibit axon regeneration. Our additional intention was to clarify some of the confusion in the field relating to an oversimplified view of the glial scar. We would like to take this opportunity to reiterate how the current body of literature, expounding details of the glial scar, has progressed beyond a simplified and outdated understanding of this structure as a mono-cellular arrangement consisting only of astrocytes that solely limit axon regeneration. Instead, our perception of the glial scar has evolved to acknowledge the nuances of this multi-cellular structure to one that is able to limit the expansion of inflammatory processes shortly following SCI and that also persists chronically to limit axon regeneration.Further, we would like to expand upon some of the details presented in the review by offering an outlook on the current state of the field and avenues for progression. This includes the specific role of chondroitin sulphate proteoglycan components in axonal growth and plasticity, and the current assessment of SCI at different stages post injury. As such, this perspective should be considered a companion piece to our original work,adding new insights from across the field from recent publications.