Enzyme replacement therapy for murine mucopolysaccharidosis type VII.

Recombinant mouse beta-glucuronidase administered intravenously to newborn mice with mucopolysaccharidosis type VII (MPS VII) is rapidly cleared from the circulation and localized in many tissues. Here we determine the tissue distribution of injected enzyme and describe its effects on the histopathology in 6-wk-old MPS VII mice that received either one injection of 28,000 U recombinant beta-glucuronidase at 5 wk of age or received six injections of 28,000 U given at weekly intervals beginning at birth. These mice were compared with untreated 6-wk-old MPS VII mice. The single injection decreased lysosomal distention in the fixed tissue macrophage system. MPS VII mice that received multiple injections had 27.8, 3.5, and 3.3% of normal levels of beta-glucuronidase in liver, spleen, and kidney, respectively. Brain had detectable beta-glucuronidase, ranging from 2.0-12.1% of normal. Secondary elevations of alpha-galactosidase and beta-hexosaminidase in brain, spleen, liver, and kidney were decreased compared with untreated MPS VII mice. Although no improvement was observed in chondrocytes, glia, and some neurons, the skeleton had less clinical and pathological evidence of disease and the brain had reduced lysosomal storage in meninges and selected neuronal groups. These data show that recombinant beta-glucuronidase treatment begun in newborn MPS VII mice provides enzyme to most tissues and significantly reduces or prevents the accumulation of lysosomal storage during the first 6 wk of life. Whether therapy begun later in life can achieve this level of correction remains to be established.     

Behavioral consequences of bone marrow transplantation in the treatment of murine mucopolysaccharidosis type VII.

The gusmps/gusmps mouse is a model of the human lysosomal storage disease mucopolysaccharidosis type VII caused by deficient beta-glucuronidase activity. Bone marrow transplantation has been shown to correct some of their biochemical and pathological abnormalities but its efficacy in correcting their neurological functional deficits is unknown. We transplanted the neonatal gusmps/gusmps mice and their normal controls and evaluated their central nervous system function with two behavioral tests: the grooming test, a developmentally regulated and genetically based activity, and a Morris water maze test which assessed spatial learning abilities. The two transplanted groups groomed less than the normals, were unable to remember the location of an invisible platform from day to day, and were severely impaired at developing strategies to locate the platform in unfamiliar locations. The performance of both normal and mutant transplanted groups was clearly inferior to the untreated normals and, in some instances, close to or worse than the untreated mutants, even though the enzyme abnormalities of the mutants have been partially corrected. Hence, the behavioral deficits in the mutant mice were not restored to normal while similarly treated normal mice showed significant functional deterioration, indicating the detrimental consequence of this therapy in the neonatal period.     

神经干细胞移植治疗帕金森病的实验研究

目的:神经干细胞的发现为神经系统退行性疾病的治疗,提供了新的方法。通过碱性成纤维细胞生长因子(basicfibroblastgrowthfactor,bFGF)反应性神经干细胞的移植,探讨神经干细胞在帕金森病(Parkinson'dis-ease,PD)治疗中的作用。方法:体外用bFGF作为丝裂原培养E16大鼠中脑神经干细胞,经BrdU标记后植入PD大鼠纹状体,了解PD大鼠旋转行为的改善情况。结果:神经干细胞移植组PD大鼠旋转行为改善明显。结论:bFGF反应神经干细胞移植对PD有明显的治疗作用。     

Enzyme replacement therapy for murine mucopolysaccharidosis type VII leads to improvements in behavior and auditory function.

Mucopolysaccharidosis type VII (MPS VII; Sly syndrome) is one of a group of lysosomal storage diseases that share many clinical features, including mental retardation and hearing loss. Lysosomal storage in neurons of the brain and the associated behavioral abnormalities characteristic of a murine model of MPS VII have not been shown to be corrected by either bone marrow transplantation or gene therapy. However, intravenous injections of recombinant beta-glucuronidase initiated at birth reduce the pathological evidence of disease in MPS VII mice. In this study we present evidence that enzyme replacement initiated at birth improved the behavioral performance and reduced hearing loss in MPS VII mice. Enzyme-treated MPS VII mice performed similarly to normal mice and significantly better than mock- treated MPS VII mice in every phase of the Morris Water Maze test. In addition, the auditory function of treated MPS VII mice was dramatically improved, and was indistinguishable from normal mice. These data indicate that some of the learning, memory, and hearing deficits can be prevented in MPS VII mice if enzyme replacement therapy is initiated early in life. These data also provide functional correlates to the biochemical and histopathological improvements observed after enzyme replacement therapy.     

异种大鼠神经干细胞脑内移植未导致明显的免疫排斥反应

目的 探讨异种大鼠神经干细胞脑内移植是否会导致明显的免疫排斥反应。方法 制作SD大鼠大脑中动脉夹闭致脑缺血模型，将体外培养的Wistar大鼠神经干细胞移植到脑缺血同侧或对侧的纹状体区，在移植后的不同时间杀死大鼠，研究脑内单核吞噬细胞的侵润、脾脏淋巴滤泡增殖以及脑内干细胞存活和迁移的情况。结果 移植后的干细胞在脑内大量存活并向损伤区域迁移；与未接受干细胞移植的对照组相比较，干细胞移植组大鼠并未发生明显的脑内单核吞噬细胞侵润和脾脏淋巴滤泡的大量增殖。结论 异种神经干细胞脑内移植未导致明显的免疫排斥反应。     

Murine mucopolysaccharidosis type VII: long term therapeutic effects of enzyme replacement and enzyme replacement followed by bone marrow transplantation.

We demonstrated previously that short term administration of recombinant beta-glucuronidase to newborn mice with mucopolysaccharidosis type VII reduced lysosomal storage in many tissues. Lysosomal storage accumulated gradually after cessation of enzyme replacement therapy. Mice alive at 1 yr of age had decreased bone deformities and less lysosomal storage in cortical neurons. Here we compare the effects of long term enzyme replacement initiated either at birth or at 6 wk of age, and of enzyme administration initiated at birth followed by syngeneic bone marrow transplantation (BMT) at 5 wk of age. Several mice from each treatment group lived to at least 1 yr of age. Liver and spleen samples had beta-glucuronidase levels ranging from 2.4 to 19.8% of normal and showed a parallel decrease in lysosomal storage. The combination of enzyme replacement therapy followed by BMT reduced lysosomal distension in meninges, corneal fibroblasts, and bone when compared with treatment with enzyme alone. Mice treated at birth had less lysosomal storage in some neurons of the brain and the skeletal dysplasia was less severe when compared to mice whose treatment was delayed until 6 wk of age. We conclude that both enzyme replacement alone and early enzyme replacement followed by BMT have long term positive effects on murine mucopolysaccharidosis type VII. In addition, treatment started at birth is far more effective than treatment initiated in young adults.     

Murine mucopolysaccharidosis type VII. Characterization of a mouse with beta-glucuronidase deficiency.

We have characterized a new mutant mouse that has virtually no beta-glucuronidase activity. This biochemical defect causes a murine lysosomal storage disease that has many interesting similarities to human mucopolysaccharidosis type VII (MPS VII; Sly syndrome; beta-glucuronidase deficiency). Genetic analysis showed that the mutation is inherited as an autosomal recessive that maps to the beta-glucuronidase gene complex, [Gus], on the distal end of chromosome 5. Although there is a greater than 200-fold reduction in the beta-glucuronidase mRNA concentration in mutant tissues, Southern blot analysis failed to detect any abnormalities in the structural gene, Gus-sb, or in 17 kb of 5' flanking and 4 kb of 3' flanking sequences. Surprisingly, a sensitive S1 nuclease assay indicated that the relative level of kidney gusmps mRNA responded normally to androgen induction by increasing approximately 11-fold. Analysis of this mutant mouse may offer valuable information on the pathogenesis of human MPS VII and provide a useful system in which to study bone marrow transplantation and gene transfer methods of therapy.     

Encapsulation cell therapy for mucopolysaccharidosis type VII using genetically engineered immortalized human amniotic epithelial cells

Mucopolysaccharidosis type VII (MPSVII) is a lysosomal storage disease resulted from a deficiency of the enzyme beta-glucuronidase (GUSB), which is necessary for degradation of glycosaminoglycans (GAGs). The deficiency of GUSB causes progressive accumulation of GAGs and subsequent lysosomal distension in multiple tissues, including the central nervous system (CNS). In murine experiments, bone marrow transplant, enzyme replacement, viral vectors, and genetically modified cells were successfully used for correction of the visceral accumulation of GAGs, but little improvement was seen in the brain, because these therapeutic agents cannot cross the blood-brain barrier (BBB). Although direct intracerebral injection of GUSB-encoding viral vectors has been developed to bypass the BBB, the possibility of tumor formation and the toxicity of over-expressed GUSB have been reported. In this study, we generated immortalized human amniotic epithelial (IHAE) cells to maintain the effect of implantation, and encapsulated these cells to prevent harmful immunological response and tumor formation and to regulate the level of GUSB expression within the host. Moreover, we generated IHAE cells that over-express and secrete human GUSB following transduction with an adenoviral vector encoding human GUSB. Therapeutic efficacy for MPSVII was evaluated in and ex vivo experiments using these encapsulated genetically engineered GUSB-encoding IHAE cells. We confirmed that encapsulated genetically engineered IHAE cells could secrete significant amounts of GUSB outside the capsule in vitro and into the cerebral parenchyma of C3H mice seven days after the capsule implantation. Thus, encapsulation cell therapy using genetically engineered IHAE cells is an effective armamentarium for the treatment of MPSVII.     

神经干细胞移植途径的理论研究进展

神经干细胞是指来源于神经组织或能分化为神经组织、具有自我更新能力和多向分化潜能的一类细胞,近年来神经干细胞研究成为治疗神经退行性疾病和中枢神经系统损伤的热点.移植入宿主体内的神经干细胞能够向神经系统病变部位趋行、聚集,并能够存活、增殖、分化为神经元和/或胶质细胞,从而促进宿主缺失功能的部分恢复.如何将神经干细胞准确、安全移植到宿主体内,并最终迁移、聚集到脑内功能缺失部位成为该技术发展的一个重要环节.文章就目前神经干细胞动物实验和临床研究中较多采取的移植途径,包括局部注射移植、经脑脊液注射移植、经血液循环注射移植的研究进展加以概述,比较这3种方法各自的优缺点,分析神经干细胞移植的安全性和有效性,探讨哪种移植途径才是神经干细胞最适合的移植方法.     

神经干细胞NgR基因沉默立体定向移植治疗大鼠脑损伤

背景:神经干细胞具有自我增殖能力和多向分化潜能,一定条件下可以分化成神经系统的各种细胞,因此在神经损伤修复方面有着良好的应用前景.而RNA干扰避免了永久基因沉默的弊病,最有希望与神经干细胞移植相结合治疗颅脑损伤.目的:检测是否可以通过沉默NgR基因的方法提高神经干细胞立体定向移植对重型颅脑损伤大鼠的治疗效果.方法:60只雄性Wistar大鼠制成重型液压颅脑损伤模型后随机区组法分为3组,每组20只.实验组:造模24 h后向损伤的大鼠脑组织内注射NgR基因沉默的神经干细胞悬液6 μL:对照组:同法注射等量的神经干细胞悬液:空白组:同法注射等量的不含干细胞的培养液.伤后24 h,3 d,1,2周行动物神经学缺损评分.2周后处死行免疫组织化学和苏木精-伊红染色.结果与结论:转染小分子干扰RNA后,与对照组相比,实验组NgR基因蛋白表达量明显降低,移植后1周和2周,接受神经干细胞移植的大鼠神经学缺损评分明显低于对照组(P＜0.05):且其脑组织切片中的神经元数量较对照组明显增多(P＜0.01).伤后2周苏木精-伊红染色空白组可见损伤处脑组织断裂,为瘢痕连接,有明显空洞形成;对照组在移植部位出现典型的神经细胞样形态学改变;实验组出现媳型的神经细胞样形态学改变且空洞消失.免疫组织化学染色观察空白组BrdU标记的阳性细胞为(37.92±16.02)个/高倍视野,对照组为(89.68±15.34)个/高倍视野,实验组为(102.67±13.52)个/高倍视野,各组间两两比较,差异均有显著性意义(P＜0.01).提示神经干细胞NgR基因沉默后立体定向移植治疗大鼠脑损伤可明显改善重型颅脑损伤后大鼠的神经学功能.     

颅脑损伤后移植神经干细胞诱发的淋巴细胞浸润

目的探讨在外伤性脑损伤的条件下,移植同种异体神经干细胞所诱发的淋巴细胞浸润现象。方法60只SD大鼠随机分配到实验组(n=30)和对照组(n=30),制作脑损伤模型,实验组将Wistar大鼠来源的神经干细胞移植到损伤灶,对照组注射等量生理盐水。通过脑组织切片HE染色、免疫组织化学以及流式细胞术检测局部淋巴细胞浸润的表现,并通过流式细胞术检测神经干细胞的MHC-Ⅰ分子。结果神经干细胞表达MHC-Ⅰ分子的阳性率为6.57%±0.44%。HE染色和免疫组织化学显示,实验组脑损伤灶有相当数量的淋巴细胞浸润,对照组未见淋巴细胞浸润。流式细胞术显示,在损伤脑组织中,实验组的CD4 淋巴细胞数/总细胞数比率为13.28%±1.60%,对照组为0.41%±0.12%,P<0.01);实验组的CD8 淋巴细胞/总细胞数比率为5.11%±1.03%,对照组为0.57%±0.26%,P<0.01)。结论神经干细胞具有一定免疫原性,当移植到外伤性脑损伤病灶中时,可以诱发局部淋巴细胞浸润。     

In-utero diagnosis of mucopolysaccharidosis type VII in a fetus with an enlarged nuchal translucency.

Mucopolysaccharidosis type VII was diagnosed prenatally during the first pregnancy of a Turkish consanguineous couple, following diagnostic work-up of an increased nuchal translucency detected by ultrasound at 13 weeks of gestation. Mucopolysaccharidosis type VII (MPS VII) or Sly syndrome is a rare autosomal recessive lysosomal storage disease, caused by the deficiency of the enzyme beta-glucuronidase. The most severe form of MPS VII manifests itself by non-immune fetal hydrops. Tests for the diagnosis of metabolic disorders, especially lysosomal diseases, are essential when the major causes of hydrops fetalis have been excluded. The presence of a beta-glucosidase deficiency, Gaucher's disease, in the infant of the patient's sister emphasizes the importance of a complete family history in consanguineous couples and the risk for several recessive diseases in some families.     

Targeted neural differentiation of murine mesenchymal stem cells by a protocol simulating the inflammatory site of neural injury

Damaged neural tissue is regenerated by neural stem cells (NSCs), which represent a rare and difficult‐to‐culture cell population. Therefore, alternative sources of stem cells are being tested to replace a shortage of NSCs. Here we show that mouse adipose tissue‐derived mesenchymal stem cells (MSCs) can be effectively differentiated into cells expressing neuronal cell markers. The differentiation protocol, simulating the inflammatory site of neural injury, involved brain tissue extract, fibroblast growth factor, epidermal growth factor, supernatant from activated splenocytes and electrical stimulation under physiological conditions. MSCs differentiated using this protocol displayed neuronal cell morphology and expressed genes for neuronal cell markers, such as neurofilament light (Nf‐L), medium (Nf‐M) and heavy (Nf‐H) polypeptides, synaptophysin (SYP), neural cell adhesion molecule (NCAM), glutamic acid decarboxylase (GAD), neuron‐specific nuclear protein (NeuN), βIII‐tubulin (Tubb3) and microtubule‐associated protein 2 (Mtap2), which are absent (Nf‐L, Nf‐H, SYP, GAD, NeuN and Mtap2) or only slightly expressed (NCAM, Tubb3 and Nf‐M) in undifferentiated cells. The differentiation was further enhanced when the cells were cultured on nanofibre scaffolds. The neural differentiation of MSCs, which was detected at the level of gene expression, was confirmed by positive immunostaining for Nf‐L protein. The results thus show that the simulation of conditions in an injured neural tissue and inflammatory environment, supplemented with electrical stimulation under physiological conditions and cultivation of cells on a three‐dimensional (3D) nanofibre scaffold, form an effective protocol for the differentiation of MSCs into cells with neuronal markers. Copyright © 2015 John Wiley & Sons, Ltd.     

The transplantation of neural stem cells and predictive factors in hematopoietic recovery in irradiated mice.

A number of surprising observations have shown that stem cells, in suitable conditions, have the ability to produce a whole spectrum of cell types, regardless, whether these tissues are derived from the same germ layer or not. This phenomenon is called stem cell plasticity, which means that tissue-specific stem cells are mutually interchangeable. In our experiments, as a model, we used neural stem cells (NSCs) harvested from fetal (E14-15) neocortex and beta-galactosidase positive. In the first experiment we found that on days 12 and 30 after sub-lethal irradiation (LD 8.5 Gy) and (beta-galactosidase(+)) NSCs transplantation all mice survived, just as the group with bone marrow transplantation. Moreover, the bone marrow of mice transplanted NSCs contained the number of CFU-GM colonies with beta-galactosidase(+) cells which was as much as 50% higher. These differences were statistically significant, p<0.001. In the second experiment, we studied kinetics of (beta-galactosidase(+)) NSCs after their transplantation to sub-lethally irradiated mice. Histochemistry of tissues was performed on days 12 and 30 post-transplantation, and beta-galactosidase(+) cells were detected with the help of histochemical examination of removed tissues (lung, liver, spleen, thymus, and skeletal muscle). In tissues removed on day 12 post-transplantation, we found a significantly higher number of beta-galactosidase(+) cells in the spleen and thymus on day 30. While we presumed the presence beta-galactosidase(+) cells in the spleen, as spleen and reticuloendothelial system represent an important retaining system for different cell types, the presence of beta-galactosidase(+) cells in the thymus was rather surprising but very interesting. This indicates a certain mutual and close interconnection of transplanted stem cells and immune system in an adult organism. In the third experiment, we verified the mutual interchange of Sca-1 surface antigen in the bone marrow cells and NSCs before transplantation. Analysis of this antigen showed 24.8% Sca-1 positive cells among the bone marrow cells, while NSCs were Sca-1 negative. Our experiments show that NSCs share hemopoietic identity and may significantly influence the recovery of damaged hematopoiesis but do not have typical superficial markers as HSCs. This result is important for the determination of predictive factors for hemopoiesis recovery, for stem cell plasticity and for their use in the cell therapy.     

脑溢安颗粒对实验性大鼠脑出血后神经干细胞增殖的影响

目的:探讨中药脑溢安颗粒对脑出血后神经干细胞反应的影响。方法:72只雄性SD大鼠单纯随机分为假手术组、模型组、脑溢安组,采用Rosenberg方法复制大鼠脑出血模型,分别给予不同处理,于术后1,12h,1,3,5,7d处死动物,运用免疫组织化学,Westernblot方法检测脑出血后各组的nestin表达。结果:脑出血后,nestin阳性细胞增多,1d达高峰,然后逐渐降低,维持到第7天,nestin阳性细胞主要分布在海马、皮质区,且脑溢安组与模型组1d前各时间点差异无显著性意义(P>0.05),3d后各时间点差异有显著性意义(t分别为3.081,8.034,5.833,P<0.05～0.01);nestin蛋白表达有相同趋势。结论:正常脑组织中存在一定数量的神经干细胞,脑出血后神经干细胞被激活增殖,中药脑溢安能维持促进增殖,这种作用可能是通过调节细胞外因子来实现。     

不同数量神经干细胞移植治疗实验性脑梗死

背景:研究已经确证脑梗死后进行神经干细胞移植可以促进动物神经功能恢复。目的:观察在大鼠实验性脑梗死后移植不同数量神经干细胞的效果,以期寻找出能有效促进神经功能恢复的最小移植数量。方法:提取Wistar胚胎鼠脑组织,体外培养神经干细胞。利用线栓法制作Wistar大鼠脑梗死模型。在大鼠脑梗死第7天,取培养第12天的神经干细胞,预标记BrdU后通过立体定向、微量注射泵方法,分别移植低6×105、中8×105、高10×105数量的神经干细胞,并设立假移植组,通过抓握牵引实验、斜板实验评价移植3个月时4组动物的行为学变化,以及BrdU、神经元特异性烯醇化酶、胶质纤维酸性蛋白等免疫组织化学染色方法检测移植后神经干细胞与周围宿主整合及向神经元、神经元胶质细胞分化情况。结果与结论:神经干细胞移植后能在宿主脑内存活,并分化为神经元和胶质细胞促进功能恢复。移植神经干细胞后3个月时,各移植组与假移植组相比行为学评分均有显著性升高;中等数量移植组大鼠各项行为学评分明显优于低等数量移植组,而中、高等数量移植组两组之间差异没有显著性意义。提示脑梗死后移植不同数量神经干细胞可改善因脑梗死造成的功能障碍,8×105数量神经干细胞移植可以较少的数量发挥较好移植效果。     

Brca-1基因调控神经干细胞移植治疗脑梗死

背景:最近国际上有人推测神经前体细胞和神经细胞的增殖受到Brca-1基因调控.目的:观察Brca-1基因调控神经干细胞移植对SD大鼠急性缺血性脑梗死模型影响.方法:参照Longa等线栓法建立SD大鼠急性脑梗死模型.应用立体定位法,分别向模型大鼠病侧脑室内注射PBS溶液、常规培养的神经干细胞、10-5 mol/L 17β-雌二醇培养的神经干细胞.采用动物行为学评分评价模型动物不同时间点的神经功能缺损;激光共聚焦显微镜观察神经干细胞Nestin表达;TTC染色测定不同时间点脑梗死体积变化;光镜和电镜分别观察脑梗死区病理变化.免疫组织化学法检测NSE和GAFP表达.结果与结论:①17β-雌二醇培养组动物神经功能恢复程度优于常规培养组(P < 0.05).②激光共聚焦显微镜显示脑缺血再灌注组和空白干预组在4 d时荧光强度最强,7 d时荧光表达减弱,17β-雌二醇培养组也是在4 d时表达最强,但是持续表达高强度的时间长,7 d时仍能见到较强的荧光表达.③17β-雌二醇培养组脑梗死体积明显缩小,与脑缺血再灌注组和空白干预组相比差异有显著性意义(P < 0.05).④17β-雌二醇培养组细胞移植治疗7 d神经元基本无肿胀,核仁清晰,染色质分布均匀,大部分毛细血管形态正常.⑤17β-雌二醇培养组NSE和GFAP表达的阳性结果也高于常规培养组.结果表明用雌激素干预Brca-1基因表达的神经干细胞移植后治疗效果好于常规培养的神经干细胞.     

不同数量神经干细胞移植治疗实验性脑梗死

背景：研究已经确证脑梗死后进行神经干细胞移植可以促进动物神经功能恢复。目的：观察在大鼠实验性脑梗死后移植不同数量神经干细胞的效果,以期寻找出能有效促进神经功能恢复的最小移植数量。方法：提取Wistar胚胎鼠脑组织,体外培养神经干细胞。利用线栓法制作Wistar大鼠脑梗死模型。在大鼠脑梗死第7天,取培养第12天的神经干细胞,预标记BrdU后通过立体定向、微量注射泵方法,分别移植低6×105、中8×105、高10×105数量的神经干细胞,并设立假移植组,通过抓握牵引实验、斜板实验评价移植3个月时4组动物的行为学变化,以及BrdU、神经元特异性烯醇化酶、胶质纤维酸性蛋白等免疫组织化学染色方法检测移植后神经干细胞与周围宿主整合及向神经元、神经元胶质细胞分化情况。结果与结论：神经干细胞移植后能在宿主脑内存活,并分化为神经元和胶质细胞促进功能恢复。移植神经干细胞后3个月时,各移植组与假移植组相比行为学评分均有显著性升高;中等数量移植组大鼠各项行为学评分明显优于低等数量移植组,而中、高等数量移植组两组之间差异没有显著性意义。提示脑梗死后移植不同数量神经干细胞可改善因脑梗死造成的功能障碍,8×105数量神经干细胞移植可以较少的数量发挥较好移植效果。     

同种异体胚胎神经干细胞移植修复脊髓损伤的时效性观察

目的:观察同种异体胚胎神经干细胞移植对脊髓损伤大鼠双后肢运动功能的修复作用,并分析其移植时效性。方法:实验于2003-07/08在大连医科大学分子生物学实验室和大连理工大学环境与生命学院生物医学实验室完成。①取孕14￣16d的大白鼠1只,引颈处死,剖腹,取出胎鼠,钳取大脑皮质及皮质下脑室旁的脑组织,体外培养大鼠胚胎神经干细胞。②将30只成年SD大鼠按随机数字表法分为3组,即损伤对照组、早期移植组和延期移植组,每组10只。3组大鼠均制作脊髓横断损伤模型,造成大鼠下肢瘫痪,早期移植组、延期移植组大鼠分别在伤后3d及3周移植胎鼠脑组织神经干细胞。观察移植后大鼠双后肢的运动功能恢复情况,通过胶质原纤维酸性蛋白及神经元特异性烯醇化酶免疫组化染色法观察各组大鼠的脊髓组织形态学变化,胶质原纤维酸性蛋白是星形胶质细胞特异性标志蛋白,神经元特异性烯醇化酶是神经元特异性蛋白。结果:脊髓损伤建模实验纳入大鼠30只,全部进入结果分析,无脱失。①各组大鼠神经干细胞移植后双后肢的功能恢复情况:早期移植组和延期移植组大鼠双后肢的运动功能均有明显改善,但早期移植组表现尤为显著。早期移植组和延期移植组细胞移植后五六天即可见瘫痪大鼠的后肢肌力开始恢复,二三周后可出现爬行,4周后后肢活动活跃;损伤对照组大鼠的瘫痪肢体无任何恢复。②移植4周后早期移植组大鼠移植区脊髓组织的形态学变化:脊髓移植区肉眼可见有增生的组织充填,镜下有大量新生的细胞,表现为神经元和神经胶质细胞阳性染色(胶质原纤维酸性蛋白( ),神经元特异性烯醇化酶( ))。结论:神经干细胞移植对脊髓横断大鼠运动功能恢复有促进作用,早期移植疗效更好。