经枕大池神经干细胞移植治疗大鼠创伤性脑损伤的研究

Transplantation of neural stem cells via the cisterna magna for treatment of traumatic brain injury in rats

目的将神经干细胞经枕大池移植到创伤性脑损伤模型大鼠蛛网膜下腔中并观察其存活、迁移和分化，从而为神经干细胞的体内存活、迁移和分化机理研究和临床应用提供实验依据。方法体外培养BrdU标记的胚胎神经干细胞并应用免疫荧光细胞化学染色对BrdU、神经干细胞标记物nestin的表达进行鉴定；采用Feeney自由落体撞击法制做大鼠脑损伤模型，伤后24h将BrdU标记的胚胎神经干细胞经立体定向注射移植到蛛网膜下腔；制作大鼠脑组织石蜡切片，应用免疫组织化学染色检测BrdU、微管相关蛋白2（MAP2）、胶质纤维酸性蛋白fGFAP）表达；伤前24h、伤后24h及1、2周行动物运动神经功能评分。结果免疫荧光检测显示神经球的表面细胞表达nestin及BrdU；免疫组织化学染色检测到脑内损伤灶存在BrdU阳性神经干细胞、MAP2阳性神经元和GFAP阳性胶质细胞；接受神经干细胞移植的大鼠神经运动功能评分的恢复较对照组有明显提高，差异有统计学意义（P〈0．05）。结论经枕大池移植到脑损伤大鼠蛛网膜下腔中的神经干细胞能存活且具有远距离迁移能力，并明显有助于脑损伤大鼠神经运动功能的恢复。

Objective To investigate the potential of neural stem cells （NSCs） injected into the cisterna magna to migrate into the injured brain tissue to survive and differentiate into neural cells in rats with traumatic brain injury （TBI）. Methods Embryonic NSCs cultured in vitro were labeled with BrdU and identified using immunoftuorescence assay for nestin and BrdU expression. The labeled NSCs were stereotactieally injected into the subarachnoid spaces of rats 24 h after experimental traumatic brain injury. The motor neurological function of the rats was assessed 24 h before and 24 h and 1 and 2 weeks after the injury, and immunohistochemistry was used to detect the expressions of BrdU, MAP2 and GFAP in the brain tissues. Results Positive expressions of nestin and BrdU were detected on the neurospheres by immunofluorescence assay. NSC transplantation resulted in significantly improved motor neurological fimction of the rats with traumatic brain injury （P〈0.05）. Immunohistochemistry demonstrated the presence of BrdU-positive NSCs, MAP2-positive neurons and GFAP-positive glial cells in the traumatic brain tissue of rats 1 and 2 weeks after NSC transplantation. Conclusion Neural stem cells injected via the subarachnoid space can migrate into the injured rat brain tissue and differentiate into neural cells to promote the recovery of motor neurological function of rats with traumatic brain injury.