转基因小鼠脊髓源神经干细胞移植于脊髓损伤模型后的成活、分化、迁移

Survival, differentiation and migration of the spinal cord derived neural stem cells from transgenic mice transplanted into mouse models of spinal cord injury

目的将从绿色荧光蛋白（GFP）转基因小鼠胚胎脊髓分离培养的神经干细胞（NSCs）移植到小鼠脊髓损伤模型损伤处，观察小鼠运动恢复和NSCs在脊髓内的存活、迁移和分化，探讨NSCs在临床治疗脊髓损伤的作用。方法采用简单随机化分组方法将小鼠随机分为空白组（n=10）、损伤组（n=30）、细胞移植组（n=30），制备损伤模型并在损伤处进行NSCs移植，于时间节点进行Basso-Beattie—Bresnahan（BBB）评分、斜板实验和免疫组织化学检测。结果击打后小鼠双后肢均瘫痪，BBB评分为0分，移植2周后评分开始出现差异，移植组提高到（4．50±1．04）分，损伤组为（2．17±0．75）分（P=0．023）；4周时移植组为（8．17±1．47）分，损伤组为（5．33±1．03）分（P=0．015）；6周时移植组为（10．8±1．47）分，损伤组为（8．33±0．81）分（P=0．017）；8周时差异最大，移植组为（15．50±1．37）分，损伤组为（11．17±1．16）分（P=0.016）。斜板实验中在1周时移植组为（17．17±3．18）°，损伤组为（14．83±3．06）°；2周时移植组为（23．33±d．27）°，损伤组为（18．17±2．40）°；4周后两组比较差异有统计学意义，移植组为（33．83±6．30）°，损伤组为（23．50±1．76）°（P=0．024），6周时较4周变化不大，移植组为（37．50±8．50）°，损伤组为（27．67±3．56）°（P=0．029），8周时显著提高，移植组为（46．83±6．05）°，损伤组为（36．33±7．23）°（P=0．019）。荧光检查结果显示移植的NSCs会在体内存活并迁移，部分保持未分化状态，少量分化为胶质细胞，向神经元分化较少。结论NSCs对脊髓损伤的恢复有促进作用，这种作用是通过移植细胞后形成一个有利于恢复的微环境，增加向神经元分化的比例来促进恢复。

Objective To observe the mice motion recovery and neural stem cell （NSCs） survival, migration and differentiation after the green fluorescent protein （GFP） ＋ - positive NSCs which was isolated and cultivated from mouse embryonic spinal cord was transplanted into mouse models of spinal cord injury lesions. Methods mice were randomly divided into control group （ n = 10）, injury group （ n = 30） and cell transplanted group （ n = 30）. The NSCs were transplanted into spinal cord injury after establishing the injured models. The Basso- Beattie- Bresnaban （BBB） function scores, inclined plane test and immunohistochemistry testing were respectively evaluated and recorded 1, 2, 4, 6, 8 weeks after the operation. Results The mouse hind limbs were paralyzed after hitting and BBB scores were 0. The transplanted group increased to 4. 50 ± 1.04, injury group was 2. 17 ± 0.75, scores began to appear differences at 2 weeks （P = 0. 023 ）. The scores of transplanted group was 8.17 ± 1.47 and injury group was 5.33 ± 1.03 at 4 weeks （P =0. 015）. The scores of two groups were increased with the passage of time after 4 weeks. The scores of transplanted group was 10. 8 ± 1.47 and injury group was 8. 33 ± 0. 81 at 6 weeks （ P = 0. 017）. The difference was biggest at 8 weeks, transplanted group was 15.50 ± 1.37 and injury group was 11.17 ± 1.16 （P = 0. 016 ）. The angle of transplanted group was （17. 17 ± 3.18 ）° and injury group was （ 14. 83 ± 3.06 ） ° at 1 weeks. At 2 weeks, the angle of transplanted group was （23.33 ±_ 4.27 ）° and injury group was （18.17 ±2. 40）°. The two groups＇ results appeared significant differences at 4 weeks in inclined plane test （P =0. 024）. The transplanted group was （33.83 ±6. 30）°, injury group was （23.50 ± 1.76）°（ P = 0. 029）. The small difference of The difference was biggest at 8 weeks, transplanted group was （46. 83 ±6. 05 ） ° and injury group was （36. 33 ± 7. 23 ）°（ P = 0. 019 ）. The transplanted NSCs can survive and migrate in the body, some of which can remain undifferentiated state, a small part of which can differentiate into glia, less of which differentiate into neurons. Conclusion There was a promoting effect of NSCs for the recovery of spinal cord injury. It was forming a micro - environment conducive to resume by transplanting cells and increasing the proportion of neurons to promote recovery.