Survial And Migration Of Neural Stem Cells In Rat Spinal Cord

Neural stem cells(Neural stem cells, NSCs) are multipotential progenitor cells that have self-renewal activities. NSCs are capable of generating various kinds of cells composing the central nervous system, that is, neurons, astrocytes, and oligodendrocytes. It has been proved that there exist multipotential stem cells in CNS. After transplantation into CNS, NSCs can immigrate and differentiate further, and they can integrate with host cells to perform neural functions. The isolation and successful culture of those stem cells have brought a new hope of repairing the damages of CNS and treating neuraldegenerative disorders. And it has also offered an ideal gene carrier to study the mechanisms of neuralgenesis and hereditary diseases. So it is widely accepted that using transplantation of exogenetic neural stem cells is a method which has broad application prospects.The construction of culture system is premier to acquire and study neural stem cells. It has been proved that cells group cultured in serum-free medium can differentiate into 3 kinds of cells of CNS: neurons, astrocytes, and oligodendrocytes. This shows that the cells group (neurosphere) has the ability of self-reproduction. The successful culture of neural stem cells makes it possible to study the differentiation of neural stem cells.In our study we used the serum-free culture technique. Neural stem cells were cultured in DMEM-F12 medium supplemented with B27,EGF and bFGF. Suspended neurosphere which were positive stained of Nestin,Musashi were neural stem cells .Natural differentiated neurospheres were identified by NSE,GFAP andO4. The cells were positive stained of anti-NSE,anti-GFAP and anti-O4. This manifested that acquired neural stem cells had the ability of multi-direction differentiation.In our study, we transplanted the neural stem cells labeled with BrdU into spinal cord of rats directly. After 2 weeks, materials were acquired and cut into slices. After stained by BrdU immunohistochemistry, positive cells were seen in meninx of transplantation area and they distributed in white substance of spinal cord sparsely. This result showed that neural stem cells could survive after transplantation into spinal cord. The existence of positive cells around spinal central canal showed that neural stem cells could immigrate within body after transplantation.Now neural stem cell has been regarded as an ideal material of transplantation and substitute for CNS diseases. It has a broad prospect to treat spinal injury with transplantation of neural stem cells modified by exogenetic neural stem cells and neural trophic factors. With the deeper acknowledgment of neural stem cells, and with more studies on mechanisms of secondary damages after spinal cord injury in cell and molecule level, NSC will show more broad application prospects and clinical values.