许旺细胞与PLGA共同移植于大鼠全横断脊髓损伤的实验研究

目的观察许旺细胞与PLGA组织工程材料共同移植于大鼠全横断脊髓损伤处对脊髓修复的影响。方法许旺细胞与PLGA体外共同培养后行扫描电镜观察,将其共移植于大鼠横断性脊髓损伤处,不同时间行BrdU／MBP免疫组化、天青-美蓝染色、透射电镜、运动功能评分（BBB）、运动诱发电位（MEP）、股四头肌复合肌肉动作电位（CMAP）、体感诱发电位（SEP）检测。结果扫描电镜下许旺细胞在PLGA内生长良好。6个月后移植物内可见BrdU／MBP免疫组化双染阳性细胞,天青-美蓝染色和透射电镜观察可见新生的髓鞘及形成髓鞘的许旺细胞。BBB评分各组间无显著性差异,MEP和SEP检测移植后6个月所有大鼠波形仍未恢复,但T（11-12）椎间隙可记录到SEP波。结论许旺细胞与PLGA具有良好的组织相容性,共同移植于损伤脊髓可促进轴突生长及髓鞘再生,但没有与损伤远端联系。

Research about schwann cells and PLGA implanted to rat transected spinal cord

OBJECTIVE: To investigate the recovery of rat transected spinal cord injury after implantation of Schwann cells combined with poly (lactide-co-glycolide) (PLGA). METHODS: Schwann cells were expanded, co-cultured with PLGA for 9 days in vitro, and then analyzed with scanning electron microscope (SEM). Rat spinal cord at the level of T(9) was transected. Schwann cells labeled with BrdU and PLGA scaffold were implanted to injury site. After 1, 3, 6 months, BrdU/MBP immunohistochemistry double staining, semi-thin sections stained thionin and ultra-thin section were performed to investigate myelin renew. BBB open field locomotion, motor evoked potential (MEP), compound muscle action potential (CMAP) and somatosensory evoked potential (SEP) were recorded. RESULTS: Schwann cells grew well on PLGA under SEM. BrdU/MBP double positive cells would been seen, remyelination was thin and formed by Schwann cells at 6 months later under electron microscope (EM). BBB behavioral tests revealed no significant difference in recovery comparing with experiment group and control group. The results of MEP, CMAP and SEP showed no significant improvement in the conduction of spinal cord. CONCLUSIONS: There are the compatibility between Schwann cells and PLGA. Although remyelination was found in morphology, function conduction of spinal cord failed to be established.