Effects of Fetal Spinal Cord Transplants on Injured Rat Spinal Cord

ABSTRACT

OBJECTIVE: Previous studies have demonstrated that axon regeneration or remyelination after spinal cord injury occurs when provided with a suitable substratum such as fetal spinal cord (FSC). We carry out this study to determine whether FSC transplants can reduce the glial scar at the interface between host and graft. METHODS: Hemisectioned spinal cord injury was made by aspiration at T3 or T4 spinal cord level in rat. Cell suspension of E-14 FSC was introduced into the injured cavity contaning glial scar tissue. To indentify the transplanted cells from host tissue, FSC cells were labeled with DiI. Rats were sacrificed at 1, 2, 3, and 8 weeks after transplanation and spinal cord was undergone serial sections for immunocytochemistry and histological observation. The observation by electron microscope was carried out too. RESULTS: We could observe that the FSC transplants survived in host spinal cord and generally occupied most of the neuron-depleted area. Examination of serial sections through the graft-host interface which had been immunoreacted for glial fibrillary acidic protein demonstrated that the glial scar was no longer a continuous wall separating the graft and host tissues at eight weeks after injury. We could observe oligodendrocyte and the reformed myelin at the interface by electron microscope. CONCLUSION: The fetal spinal cord transplant can reduce an established glial scar or restrict the reformation of a scar following surgical manipulation, and that the FSC transplant can promote remyelination.