The Study On Spinal Cord Injury Repair By Co-Transplantation Of IPS-derived Neural Stem Cells And Actived Schwann Cells

?Objective?Spinal cord injury has been a major problem for the medical community.Cell transplantation promotes nerve repair after SCI is currently hot research.The discovery of induced pluripotent stem cells breaks the traditional view on stem cell differentiation and culture.In this study,induced iPS cells were used as “seed cells”,and the pre-prepared PCL was used as a tissue engineering scaffold.Western-Blot,immunohistochemical staining and limb function scores were used to explore the effectiveness of repairing spinal cord injury,in order to provide new ideas and theoretical basis for clinical repair of spinal cord injury.?Methods?1.Umbilical cord blood mononuclear cells were induced into iPS cells and cultured in human embryonic stem cell culture medium,and then cultured in vitro using neural stem cell conditioned medium.2.Systematic observation of the differentiation rate and characteristics of human umbilical cord blood derived induced pluripotent stem cells(HUCB-iPS)in the direction of neural cells under conditioned medium.3.The prepared PCL bio-scaffold was incubated with both cells to allow the seed cells to migrate into the tissue engineering scaffold.4.Western-blot method was used to detect the changes of the expression levels of the relevant neurotrophic factors after injury.To explore the principle of transplantation of tissue-engineered iPS cells to repair spinal cord injury,and to explore the mechanism of iPS cells repairing spinal cord injury and promoting axonal regeneration.?Results?1.After inducing iPS cells with the four transcription factors in vitro for 18 days,we can see that the iPS cells have larger colonies with clear boundaries and are isolated from the MEF cells.After immunostaining with NANOS,SOX2,OCT4 and DAPI of iPS cells,iPS cells were seen to be green under NANOG and OCT4 staining,and red under SOX2 staining and blue under DAPI staining.After staining with Nestin and DAPI,under the fluorescence microscope,Nestin staining of neural stem cells was green,DAPI staining was blue,and the size of cell spheres was uniform.2.Spinal cord tissue from different groups and performed HE staining.Among them,the reduction of cavities in the group of ASCs combined with iPS-NSCs co-culture stent implantation was most obvious and showed A larger amount of cell proliferation and infiltration suggest that the combined transplantation of ASCs and tissue-engineered iPS cells can improve the local pathological structure after SCI and improve the recovery of motor function after spinal cord injury in experimental animals.3.In the evaluation of hindlimb motor function,the BBB scores of the experimental animals reached the highest on the 56 th day in all groups.The BBB score of some experimental animals in this group can reach 12 points in the eighth week after cell transplantation.4.Eight weeks after cell transplantation,Western-blot was used to detect the expression of NT3,GDNF,NGF and other neurotrophic factors and inflammatory factors.The results showed that there was no significant difference in NT3 expression in spinal cord between the cell transplantation group and the spinal cord injury group at the eighth week(P > 0.05).The results showed that the expression of GDNF and NGF was higher in the spinal cord injury group than in the spinal cord injury group at the eighth week(P < 0.05).?Conclusions?In this experiment,human iPS cells were successfully induced from umbilical cord blood mononuclear cells and iPS cells were successfully induced in the direction of neural stem cells.In cell transplantation for the treatment of spinal cord injury,iPS-NSCs combined with ASCs transplantation for the treatment of subacute spinal cord injury have a better effect on the immunohistochemical staining and the limb function score of the experimental animals than the transplanted cells alone.