不同来源嗅鞘细胞修复脊髓损伤的效果比较

背景：研究表明嗅鞘细胞所分泌的细胞黏附分子和神经营养因子具有保护脊髓神经元和促进脊髓轴突再生的效应。目的：比较嗅球及嗅黏膜固有层来源的嗅鞘细胞异体移植修复脊髓损伤的能力。设计、时间及地点：随机对照动物实验，于2007-06/2008-06在西电集团医院中心实验室完成。材料：随机选取雄性3月龄及23月龄SD大鼠各6只，分为实验组(23月龄)和对照组(3月龄)，用于嗅鞘细胞的体外培养和纯化；SD大鼠30只随机分为乳鼠嗅球嗅鞘细胞移植组、正常嗅黏膜嗅鞘细胞移植组、对照组，每组10只。方法：30只SD大鼠制造脊髓损伤模型，分别将体外培养的乳鼠和SD大鼠嗅鞘细胞进行脊髓损伤模型的异体移植，对照组不做移植。主要观察指标：术后4，8周，进行BBB神经功能评分，诱发电位，组织病理学观察。结果：实验过程中大鼠死亡7只，各组死亡率大致相同。移植后第4，8周时，乳鼠嗅鞘细胞移植组、正常嗅黏膜嗅鞘细胞组评分差异无显著性意义(P > 0.05)，均显著高于空白对照组(P < 0.001)；嗅鞘细胞移植2组评分8周高于4周(P < 0.01)。术后4周，各组动物均未引出运动诱发电位，移植后8周时，2组嗅鞘细胞移植组动物均可引出运动诱发电位，2组差异无显著性意义(P > 0.05)，空白对照组动物仍未引出运动诱发电位(P < 0.001)。移植后8周，2组嗅鞘细胞移植组脊髓损伤区有较多细胞浸润，对照组细胞数目较少。结论：来源于嗅球与嗅黏膜的嗅鞘细胞对脊髓损伤修复均有促进作用，且两者作用无明显差异。

Different sources of olfactory ensheathing cells repairs spinal cord injury

BACKGROUND: Studies showed cellular adhesion molecule and neurotrophic factor secreted from olfactory ensheathing cells (OECs) could protect the spinal neurons and promote the regeneration of spinal axon. OBJECTIVE: To compare the competence to repair spinal cord injury between olfactory mucosa OECs and olfactory bulb OECs.DESIGN, TIME AND SETTING: Randomized control animal experiment was performed in the central laboratory of Xidian Group Hospital between June 2007 and June 2008. MATERIALS: Twelve male SD rats were randomized selected and divided into experiment group (n=6, 23 months old) and control group (n=6, 3 months old). They were used for in vitro culture and purification of OECs; other 30 SD rats were randomized into three groups of 10 rats each: neonatal rat olfactory bulb OECs transplantation group, normal olfactory mucosa OECs transplantation group and blank control group. METHODS: Spinal cord injury models were produced in 30 rats, which were transplanted with the neonatal rat or SD rat OECs cultured in vitro. No transplant was given in the control group. MAIN OUTCOME MEASURES: At 4 and 8 weeks postoperation, the Basso, Beattie, Bresnahan (BBB) score for nerve function, the evoked potential of legs and the histopathological diversify of injured spinal cord.RESULTS: Seven rats died during the experiment process, and the death rate was similar between groups. At 4 and 8 weeks postoperation, there was no significant difference in the BBB scores between neonatal rat olfactory bulb OECs transplantation group and normal olfactory mucosa OECs transplantation group (P > 0.05), which were both significantly higher than blank control group (P < 0.001); the BBB scores in two transplantation groups were higher at 8 weeks than at 4 weeks (P < 0.01). At 4 weeks postoperation, no animal was shown to elicit motion evoked potential, but it was present in two transplantation groups at 8 weeks, with no significant difference between two groups (P > 0.05). The blank control group had still no motion evoked potential (P < 0.001). At 8 weeks postoperation, more cell infiltrations were found in the injured spinal cord of two transplantation groups, while few in the control group. CONCLUSION: Both OECs dissociated from olfactory bulb and olfactory mucosa have the same ability to repair the injured spinal cord, and their effect is similar.