脑内注射人胚鞘细胞对颅脑损伤大鼠神经及运动功能缺失的影响

背景中枢神经再生失败的主要原因之一是损伤后中枢神经内的微环境(缺乏生长所需的神经营养因子、分泌产生抑制因子、胶质瘢痕形成等)不利于轴突的再生.为了促进中枢神经系统损伤后轴突再生,改善损伤区再生微环境很重要.其中嗅鞘细胞是近年来最为吸引人注目的一种治疗中枢神经损伤的有力工具.目的探讨嗅鞘细胞在大鼠颅脑损伤中的作用及其是否能在颅脑损伤后减少神经功能上的缺失.设计以实验动物为研究对象,随机对照实验研究.单位一所大学医院的神经外科.材料实验在2003-04/08在开封铁路医院神经外科中心实验室完成.选用成年健康Spraque-Dawley大鼠100只,雌雄不拘,体质量250～350g,随机分为正常组,脑损伤组,生理盐水组,嗅鞘细胞组.每组25只.每组再分为5个亚组,每个亚组5只大鼠.干预制备颅脑损伤的大鼠模型,在受伤后立即将嗅鞘细胞移植到受损的脑组织中,1,4d,1,2,4周对大鼠进行神经损伤评分,将大鼠处死观察嗅鞘细胞在脑组织中的分布情况.主要观察指标①大鼠的神经功能恢复情况.②嗅鞘细胞在脑组织中的分布情况.结果在术后2,4周时,嗅鞘细胞组NSS评分与脑损伤组和生理盐水组相比,差异有显著性意义.通过苏木精-伊红染色切片中的形态结构或GFAP和p75免疫化学,可见嗅鞘细胞在移植部位存活并迁移到周围邻近组织.统计不同时间段的5个6μm厚的冠状位组织切片中的p75阳性细胞总量,发现嗅鞘细胞的数量随着时间的推移逐渐变少.结论颅脑创伤后立即移植嗅鞘细胞到创伤的脑组织,嗅鞘细胞可在移植部位存活并迁移到周围邻近组织,与对照组相比,给予嗅鞘细胞能显著的降低颅脑创伤后引起的神经运动功能障碍.

Effect of human germinal sheathed cells injected into the brain on neurological and motor function impairment in rats after traumatic brain injury

BACKGROUND: One of the main causes of the failure of central nerve regeneration is that the microenvironment (lack of nerve growth factor, inhibitory factor produced by excretion and formation of glial scar) in the injured central nerves is not favorable for the regeneration of axons. Therefore, it is important to improve the microenvironment of injured area for the regeneration of axons. Recently, olfactory ensheathing cells (OECs) have been attracting much attention as a key method to treat central nervous injury.OBJECTIVE: To investigate the effect of OECs on traumatic brain injury (TBI) in rats and whether they can reduce neurological impairment after TBI.DESIGN: A randomized controlled experimental trial based on experimental animals.SETTING: Department of neurosurgery in a hospital affiliated to a university.MATERIALS: The experiment was conducted in the Central Laboratory of Department of Neurosurgery, Kaifeng Railway Hospital from April 2003 to August 2003. Altogether 100 healthy adult SD rats of either gender,weighting 250- 350 g, were randomly divided into four groups: normal group, TBI group, normal saline group and OEC group with 25 rats in each. Each group was further divided into five subgroups with 5 rats in each.INTERVENTIONS: The models of TBI in rats were established, and OECs were transplanted into brain tissues immediately after injury. The scores of nerve injury were assessed in the rats at day 1, day 4, week 1, week 2 and week 4. The distribution of OECs in brain tissues was observed after the rats were sacrificed.MAIN OUTCOME MEASURES: Neurological function recovery of rats and distribution of OECs in brain tissues.RESULTS: At week 2 and week 4 after operation, neurological severity scores (NSS) in OEC group significantly differed from those of TBI group and normal saline group. HE staining or immunohistochemistry of GFAP and p75 revealed that OECs could survive in the transplanted site and migrate toward the surrounding tissues. The total number of p75 positive cells in five coronal tissue slices of 6 μm thick was added up at different intervals. The results showed that the number of OECs was decreased with the passing time.CONCLUSION: OECs can survive in the transplanted site and migrate to the surrounding tissues when they are transplanted into the iujured brain tissues immediately after TBI. Giving OECs can reduce neurological and motor dysfunction induced by TBI.