ABSTRACT
@#ObjectiveTo investigate Schwann cells whether survival and migration after transplanted to central nervous system for a long-term.MethodsThe Schwann cells of rat were expended in vitro, the part of them were labeled with 5'-bromodeoxyuridine (BrdU) and transplanted to rat's middle brain injured by electric needle stimulus, the others were labeled with Hoechst 33342, seeded to PLGA scaffold, and transplanted to rat's transected spinal cord. 8 and 11 months later, rat brain and spinal cord were taken out respectively, examined by BrdU immunohistochemistry and fluorescence microscope.ResultsBrdU positive cells could be seen after 8 months and migrated toward cerebral cortex. Hoechst 33342 positive cells could be identified in scaffold and transected spinal cord after 11 months under fluorescence microscope.ConclusionGrafted Schwann cells can survive in central nervous system for a long-term and migrate toward distance.
ABSTRACT
OBJECTIVE: Recent advances in stem cell biology make it possible to induce the regeneration of injured axons and to replace lost cells in the injured spinal cord. It has been found that stem cells in human cord blood differentiate into mature neurons and glial cells both in vitro and in vivo. These findings suggest that human umbilical cord blood cells(HUCBs) can be used as therapeutic donor cells in cases of spinal cord injury. METHODS: To attempt the repair an injured cord following spinal cord injury(SCI), we transplanted HUCBs into contused spinal cords. This was found to promote a long-term improvement in neurologic function relative to a lesion-control group. HUCBs were cultured in vitro for 7 days. Bromodeoxyuridine(BrdU) was added to the media to allow the BrdU to integrate into dividing cells. Cultured HUCBs(2x106 cells) were then injected into the injury epicenter 7 days after SCI. The Basso-Beattie-Bresnahan(BBB) locomotor rating system was used to score functional improvement in HUCBs transplanted rats. Immunohistochemical staining for neurofilament, macrotubule associated protein 2(MAP-2), glial fibrillary acidic protein(GFAP), and nestin was performed. RESULTS: Immunohistochemical analysis 5 weeks after SCI showed that gliogenesis of the transplanted donor HUCBs had occurred within the adult rat spinal cord. These donor-derived astrocyte-like cells extended their processes into the host tissues and integrated well. HUCBs derived neurons(neurofilament, MAP-2) and nestin expressing cells were also detected. Behavior analysis using BBB rating scores showed that functional improvement was greater in transplanted rats than in non-treated rats. CONCLUSION: HUCBs are one of the potential sources for transplantation material for the treatment of SCI.