Ethological And Pathological Research Of Repair Of Spinal Cord Injury With Schwann Cells And Neural Stem Cells

Objective: Spinal cord injury (SCI) can the neuronal death, axonaldegeneration and demyelination of the injured site, which has highincidence and morbidity. Therefore, SCI treatment is a difficulty problemin medical profession. Schwann cell is a functional cell which isdistributed in peripheral nervous system, the base membrane of outersurface layer of Schwann cells play an important role in the regenerationof nerves. The neural stem cells (NSCs) have the ability to differentiateinto neurons, astrocytes and oligodendrocytes, which can self-update,and provide a large population of cells in brain tissues. Both Schwanncell and NSC could help repair SCI in a certain degree; however, theirsynergy has not yet been studied. The purpose of our study is to find aneffective method to repair SCI, and to evaluate the feasibility andsignificance of this method.Methods: In this study, we used the improved Allen’s modeling methodto prepare SCI model in rats; After the preparation, the SCI model wasassessed with Basso, Beattie&Bresnahan locomotor rating scale (BBBscale) and histopathologic methods. At the same time, the Schwanncells and neural stem cells of fetal rats were isolated and cultured, andthe cell purity was identified. The successful SCI models were treatedwith Schwann cells, neural stem cells and the combination of Schwannand NSCs to repair the spinal cord injury.1105cells were injected into rats via tail vein for successive7days. One, two, four and eight weeksafter injection, the motor function of rats were evaluated with BBB scale,and the spinal cord injury repairing was evaluated with HE staining.Results: In this study, we used neural stem cells, Schwann cells and thecombination of NSCs and Schwann cells to treat SCI rats. The resultsshowed that the motor function of rats was recovered well in thecombination of NSCs and Schwann cells group, the BBB scores wereincreased significantly at week8; however, the NSC alone group orSchwann cell alone group, the BBB scores were increased in a certaindegree, but the effects were weaker than the combination group. HEstaining results showed that the normal gray matter and white matterwere restored in the combination group, and the spinal cord tissues hadnormal morphology without deformation or shrinkage; in the NSC alonegroup or Schwann cell alone group, although the morphology of spinalcord tissue was recovered at a certain degree, the impaired range wassmaller, and the gray matter and white matter were more than controlgroup, there were still a small amount of microcapsule cavity.Conclusion: Our study found the SCI model in rats could be repaired byNSCs and Schwann cells homing to the site of injury. In the process ofspinal cord repairing, the NSCs and Schwann cells can secrete lots ofneurotrophic factors and related genes and proteins, these factorsultimately contributed to SCI repair. Our study provided a reference for treatment of patients with spinal cord injury with a greater clinicalsignificance.