Effect Of Transplanting NSCs With PLGA In The Treatment Of Hemisected Spinal Cord Injury In SD Rats

Background: At present,it’s a difficult problem that how to prevent 、treatment and rehabilitation Spinal Cord injury. However,the development of biological technology and tissue engineering technology to bring new therapies for the trantment of spinal cord injury.Object: To study the effect of transplantation of Neural stem cells combined with Poly-Lactic-co-glycolicacid on the hemisected spinal cord injury in SD rats.Methods:(1) The NSCs used by the method of mechanical and pancreatin digestant isolation and culture from brain tissue which come from neonatal rats, identified by immuno-fluorescence assay, compared the cell ball diameter and number at the cultivation of 2, 5, 7 days,and compared the clone reproduction rate by MTT detected.(2) 72 female SD rats were divided into 6 groups: normal group, sham operation group, operation group, NSCs transplantation group, PLGA transplantation group, NSCs+PLGA transplantation group. The sham operation group was only removed Lamina;The normal group was do nothing;other groups made hemisecion Spinal Cord transected. On the seventh day after surgery, the operation group move DMEM/F12 liquid into the spinal cord injury; the NSCs transplantation group was transplant NSCs through micro—inject; PLGA transplantation group was transplant PLGA scaffold; NSCs+PLGA transplantation group was transplant the complex of NSCs and PLGA scafford; BBB evaluation and IP tests were performed at the day pre-operation,the7 day post- operation,the 1, 2,4,8 weeks post—transplantation.At the 2,4,8 weeks post—transplantation, electrophysiological examination 、HE staining test of spinal cord pathology were performed.Results:(1)Mechanical and trypsin digestion method can successfully culture NSCs,Immunofluorescence staining showed that Nestin, NF-200, GFAP staining were positive. The number and diameter of the NSCs ball by the mechanical isolation to culture were better than pancreatin digestant isolation(p<0.05). Proliferation ability of NSCs by the mechanical isolation to culture was also better than pancreatin digestant isolation by MTT detected at the cultivation of 2, 5, 7 days(p<0.05).(2) The mean score of BBB and IP in NSCs transplantation group, PLGA transplantation group, NSCs+PLGA transplantation group was significantly higher than that in operation group at 4,8 weeks post—transplantation(p<0.05). The mean score of BBB and IP in NSCs+ PLGA transplantation group significantly higher than that in NSCs transplantation group, PLGA transplantation group at 4, 8 weeks post—transplantation(p<0.05).(3) At 2,4,8 weeks after transplantation,the latent of MEPs was gradually shortened.There was a statistically significant difference in NSCs transplantation group, PLGA transplantation group and NSCs+PLGA transplantation group compare with operation group at 2, 4, 8 weeks after transplantation(p<0.05). It’s also have a statistically significant difference in NSCs+PLGA transplantation group compare with NSCs transplantation group and PLGA transplantation group at 4,8 weeks after transplantation.(4) After HE staining of spinal cord tissue, it Can be observed that the cavity and scar tissue appeared in each groups at 8 weeks after transplantation. the cavity and scar tissue in NSCs+PLGA transplantation group was less than NSCs transplantation group and PLGA transplantation group.Conclusion:(1) Mechanical and trypsin digestion method can successfully culture NSCs, but NSCs clone proliferation which can from group is better than those can from trypsin digestion group.(2) The transplantation of NSCs+PLGA complex have a positive effect on the repair of spinal cord injury in SD rats by means of behavioral, electrophysiological and pathological evaluation, especially in the recovery of the motor ability of the hind limb. This study indiacte that the NSCs+PLGA complex can’t complete recoverry the fuction and anatomic structure of spinal cord if it’s intury.(3) The behavioral, electrophysiological and pathological evaluation of PLGA and NSCs also have a positive effect on the repair of spinal cord injury, but the curative effect was weaker than NSCs+PLGA complex group.