The neuroplastic and therapeutic potential of interneurons in the injured spinal cord

There is a growing appreciation for spontaneous anatomical and functional changes, or neuroplasticity, after spinal cord injury. One key element of neuroplasticity recently identified are spinal interneurons. The work presented in this thesis identifies a specific population of spinal interneurons that contribute to respiratory plasticity - the excitatory, ipsilaterally projecting population of V2a SpINs - after high cervical spinal cord injury (Aim 1). Building upon these results, we transplanted neural progenitor cells enriched with stem-cell derived V2a interneurons and found that donor cells promoted anatomical and functional repair of the phrenic (respiratory) circuit. These studies serve as a basis for ongoing work focused on identifying other interneuronal phenotypes that may be beneficial for both motor and sensory repair after injury. Understanding the neuroplastic and therapeutic potential of spinal interneurons may help identify novel therapeutic targets for functional repair of the central nervous system.