骨髓间质细胞源性神经球移植对大鼠脊髓损伤的修复作用

Transplantation of neurospheres derived from bone marrow stromal cells promotes neurological recovery in ratswithspinal cord injury

目的探讨骨髓间质细胞源性神经球(BMSCs-NS)移植在大鼠脊髓损伤修复中的作用。方法体外原代培养大鼠BMSCs-NS。Wistar大鼠45只,玻璃器压迫法制备胸髓(T9-10)完全损伤模型,随机分成三组:BMSCs-NS移植组(A组,n=15)、BMSCs移植组(B组,n=15)和培养液组(C组,n=15)。BBB评分评估三组大鼠后肢运动功能在不同时间段的恢复及双下肢运动诱发电位(MEPs)情况。结果 BBB平均分值为:A组,7.8±1.42;B组,5.7±0.90;C组,1.4±0.29。移植修复21d后BBB绝对分值,A组较B组和C组明显改善(B组:p<0.001;C组:p<0.0001)。移植5w后B组少数大鼠可以诱发出MEPs,但潜伏期较长(20ms)且波幅较低。2w时A组未能诱发出MEPs,但5w时的MEPs接近正常。结论细胞移植治疗能够恢复大鼠后肢的承重运动功能并能成功诱导出理想的MEPs。

Objective The aim of this study was to investigate the potential for neurological recovery by transplantation neurospheres （NS） derived from BMSCs into thoracic SCI. Methods Adult Wistar rats were used： 45 were subjected to complete thoracic spinal cord injury （SCI） performed by the balloon compression method. BMSCs were cultured in vitro to obtain NS. Groups of 15 rats each received transplants of BMSCs - NS （group A）, BMSCs （group B）, and injection of medium only （group C） into the SCI lesion. Rats from each group were evaluated and compared longitudinally for motor function recovery and motor evoked potentials （MEPs） in different time. Results The average mean of the final recovery scores in groups： A was 7.8 ±1.42, B was 5.7 ±0. 90, C was 1.4±0. 29. Five weeks after transplantation, many neuronal or axonal sproutings were observed and replaced by host cells in the SCI lesion of group A. For absolute score attained, group A showed significant improvement compared with group B （P 〈 0.001） and C （P 〈 0.000l） for all time points from 21 days after SCI. MEPs were detected 5 weeks after transplantation in a few group B rats, but the latency was more than doubled （20 ms）, and amplitude was significantly decreased. Two weeks after transplantation, no clear MEPs were recorded in group A rats. However, 5 weeks after transplantation, MEPs similar to those of normal rats were recorded in two animals from group A. Conclusion Transplanted rats could walk with weight bearing and show recovered motor evoked potentials （MEPs）.