实验性自身免疫性神经炎大鼠模型的制备与评价
2017-07-05张明原晓晶敖强
张明 原晓晶 敖强
[摘要] 目的 探索实验性自身免疫性神经炎(EAN)动物模型的建立和相关指标的评价。 方法 将20只体重140~160 g的 Lewis雌性大鼠随机分为EAN组(n = 10)和对照组(n = 10),并对各组从1~10进行编号。EAN组采用P0180-199多肽免疫,对照组注射生理盐水;免疫后观察42 d,记录行为学变化并评分;免疫后第18天检测两组大鼠神经肌肉动作电位、坐骨神经电镜组织学及免疫组织化学、腓肠肌HE染色等指标。 结果 EAN组高峰期坐骨神经复合动作电位传导速度低于对照组,差异有统计学意义(P < 0.05),振幅明显低于对照组,差异有高度统计学意义(P < 0.01)。电镜结果显示EAN组大鼠坐骨神经髓鞘结构肿胀、蜂窝改变、脱失,轴突变细或消失。HE染色结果显示EAN組大鼠腓肠肌纤维变细、胞浆淡染等炎症退行性改变。免疫组化结果显示坐骨神经髓鞘结构以水肿、脱失为主者炎症因子Iba-1(巨噬细胞)、CD3(T 细胞)增多;坐骨神经髓鞘结构以脱失为主者神经轴蛋白NF200减少;坐骨神经髓鞘结构以蜂窝状改变、脱失为主者神经髓鞘蛋白S100减少。 结论 采用P0180-199诱导的自身免疫性神经炎模型发病率高,容易复制,病理改变接近临床特发性神经炎。本研究EAN发病高峰期的各项评价指标为该模型进一步的病生理过程探讨提供了依据。
[关键词] 实验性自身免疫性神经炎;模型;脱髓鞘
[中图分类号] R745.430.5 [文献标识码] A [文章编号] 1673-7210(2017)05(c)-0026-05
[Abstract] Objective To explore the establishment of experimental autoimmune neuritis (EAN) rat model and the evaluation of related indexes. Methods Twenty female Lewis rats weighing 140-160 g were randomly divided into EAN group (n = 10) and control group (n = 10), and the number of each group was 1-10. The EAN group was immunized with P0180-199 peptide. The control group was injected with saline. After 42 days of immunization, the behavioral changes were recorded and scored. At the eighteenth days after immunization, the nerve-muscle action potential, sciatic nerve electronic microscope and immunohistochemistry and HE staining of gastrocnemius muscle and other indicators of the rats in the two groups were detected. Results The sciatic nerve conduction velocity in the peak of the compound action potential in the EAN group was lower than that of control group, with statistically significant difference (P < 0.05), and the amplitude was obviously lower than that of control group, with highly statistically significant difference (P < 0.01). The results of electron-microscope showed swell, honeycomb changes and miss out of myelin sheath, with an attenuation or disappearance of axon in the EAN group. The results of HE staining showed thinning of gastrocnemius-myofibers and stained cytoplasm and other degenerative changes in the EAN group. The results of immunohistochemistry showed that inflammatory factors Iba-1 (macrophage) and CD3 (T cells) were increased in those with swell and miss out of myelin sheath. The axonal protein NF 200 was decreased in those with miss out of myelin sheath. The myelin protein S100 was decreased in those with honeycomb changes and miss out of myelin sheath. Conclusion The autoimmune neuritis model induced by the P0180-199 has high incidence and easy copy, and the pathological changes are close to clinical idiopathic neuritis. In this study, the evaluation indexes of EAN during peak hours provide a basis for the further study of the physiological process of this disease.
[Key words] Experimental autoimmune neuritis; Model; Demyelination
实验性自身免疫性神经炎(experimental autoimmune neuritis,EAN)是国际上公认的吉兰-巴雷综合征(Guillian-Barre syndrome,GBS)的经典动物模型,该动物模型的建立对GBS自身免疫性机制的假说起到了很大的支持作用[1-4]。Waksman等在1955年首次使用周围神经匀浆在兔子身上建立了人类GBS模型[5]。其后,研究者们通过纯化的外周神经组织匀浆、髓鞘蛋白或合成多肽,来诱导各种易感动物模型,也有研究者将具有抗原特异性T细胞系静脉注入动物体内,来诱导具有抗原特性的EAN模型[6-7],其中最为广泛应用的是通过外周神经匀浆、髓鞘蛋白或合成多肽诱导的Lewis大鼠模型,例如采用P0180-199配以不完全弗氏佐剂免疫[8-9]。EAN典型病理表现是T细胞和巨噬细胞浸润,外周神经组织水肿及脱髓鞘[10-12],坐骨神经及腰髓神经根病理改变最明显,而颈丛神经及颈髓神经根则不明显[7]。1975年Allt[13]通过电镜对兔EAN模型外周神经进行观察,发现了髓鞘的两种变化:髓鞘蜂窝改变和髓鞘脱失。……
