Regenerative Medicine for Spinal Cord Injury Using Induced Pluripotent Stem Cells

Spinal cord injury (SCI) is a devastating injury that causes permanent neurological dysfunction. To develop a new treatment strategy for SCI, a clinical trial of transplantation of human-induced pluripotent stem cell-derived neural precursor cells (NPCs) in patients in the subacute phase of SCI was recently initiated. This research focuses on the establishment of cell therapy for chronic SCI, which is more challenging owing to cavity and scar formation. Thus, neurogenic NPC transplantation is more effective in forming functional synapses with the host neurons. Furthermore, combinatory rehabilitation therapy is useful to enhance the efficacy of this strategy, and a valid rehabilitative training program has been established for SCI animal models that received NPC transplantation in the chronic phase.

• 1
  Transplanted NPCs secrete neurotrophic factors to attenuate secondary damage and differentiate into neurons that establish synaptic connections with host axons, contributing to functional recovery after SCI.
• 2
  Selective chemogenetic stimulation of transplanted NPCs enhances synapse formation with host neurons, prevents atrophy of the injured spinal cord, and improves locomotor function.
• 3
  A combination of NPC transplantation and rehabilitation therapy promotes neuronal differentiation, regeneration, and maturation of neural circuits, enhancing the recovery of motor and sensory functions in chronic SCI.