The viability and differentiation of fetal spinal cord tissue after transplantation in injured mid‐cervical spinal cord

Abstract

Mid‐cervical spinal cord injury interrupts the bulbospinal respiratory pathway and causes a secondary degenerative cascade, including loss of neurons and demyelination. To date, there is no effective treatment for spinal cord injury. Fetal spinal cord (FSC) tissue is composed of neural progenitors, which may have the capability to replace the lost cell and form a neural relay between separated spinal segments. Thus, the present study was design to investigate the viability and differentiation of progenitors derived from FSC after delayed transplantation into the injured spinal cord. Embryonic day 14 FSC expressing green fluorescence protein (GFP) was transplanted into the lesion cavity in rats received unilateral C4 hemisection at 1 week post‐injury. At 8 week post‐transplantation, the viability of FSC was examined by quantifying GFP‐positive area in spinal cord sections. The histological results demonstrated that GFP‐positive area was ~70 % of contralateral (i.e., uninjured side) spinal cord tissue. Immunofluorescence staining revealed that neural cell markers [e.g., neuronal nuclei (NeuN) for neuron; glial fibrillary acidic protein (GFAP) for astrocyte; ionized calcium‐binding adapter molecule 1 (Iba1) for microglia; receptor interacting protein (RIP) for oligodendrocyte] were detected in GFP‐positive tissue. In addition, there are some serotonin and choline acetyltransferase positive cells in the graft region. These results demonstrated that transplants of FSC can survive at least for 8 week post‐transplantation and differentiate into different neural cells, suggesting FSC transplants may have the potential to repair the injured spinal cord.Support or Funding InformationNational Health Research Institutes (NHRI‐EX104‐10223NC); Ministry of Science and Technology (MOST 100‐2320‐B‐110‐004‐MY3)