嗅神经鞘细胞移植治疗实验性脊髓损伤的研究

目的:观察移植体外培养的嗅神经鞘细胞(OEC)对大鼠脊髓左半侧横断伤的治疗作用。方法:将应用改良Nash法培养的OECs移植到成年大鼠T10脊髓左半侧横断处,8周后分别采用改良Tarlov法运动学功能评分、辣根过氧化物酶(HRP)顺行示踪、透射电镜观察、P75免疫组织化学染色及HE染色等方法,观察动物的运动功能、脊髓再生的轴突和髓鞘、OEC的存活和脊髓损伤程度。结果:8周时治疗组运动学功能评分高于对照组(P<0.05);治疗组再生轴突穿越损伤区,对照组则无再生轴突穿越;超微结构显示治疗组轴突数量多于对照组,且髓鞘的完整性强于对照组,OEC表现为星形胶质细胞样和雪旺氏细胞样两种,包绕轴突髓鞘;免疫组化染色显示移植后8周OECs仍然存活,在损伤区均匀、散在分布;损伤后8周脊髓损伤区有胶质瘢痕及空洞形成。结论:移植的嗅神经鞘细胞可促进大鼠运动功能的恢复、脊髓轴突的再生和髓鞘的重塑。

Transplantation of olfactory ensheathing cells for treating experimental spinal cord injury

Objective:To observe the therapeutic effect of primary culture of olfactory ensheathing cells(OECs) in adult Wistar rats after left hemitransected spinal cord injury.Methods:The OECs cultured with modified Nash method were transplanted into left hemitransected spinal cord at T10 level.Eight weeks later,the motor functions of hindlimbs,the regenerated axons,the myelin sheaths,the survival of OECs,and the severity of spinal cord injury were determined by modified Tarlov method,HRP anterograde tracing technique,transmission electron microscopy,p75 immunostaining,and HE staining,respectively.Results:Eight weeks after transplantation,the scores of motor functions in treatment group were significantly higher than those in control group(P < 0.05).The regenerated axons in treatment group penetrated the glial scar.There were much more axons and better integrity of the myelin sheaths in treatment group.Schwann cell-like and astrocyte-like OECs that surrounded the regenerated axons were found.Transplanted OECs still survived and evenly dispersed in the injured area.There were glial scar or cavity formation in the injured area of spinal cord.Conclusion:The transplanted OECs can improve the motor function of rats and enhance the regeneration of injured axons.