嗅鞘细胞移植治疗脊髓损伤的研究进展

脊髓损伤的研究一直是神经科学界探讨的热点,而脊髓损伤后的神经修复和功能重建也一直困扰着临床医学界。既往认为中枢神经细胞的轴突损伤在自然条件下几乎不能再生,其原因是中枢神经环境不利于轴突再生、中枢神经细胞本身的再生能力低下、以及神经轴突不能穿越损伤瘢痕区到达靶细胞。脊髓损伤包括原发性损伤和继发性损伤,二者均可引起部分神经元的丢失和神经纤维的断裂;而继发性损伤可导致原发性损伤范围的扩大,使更多的神经元凋亡和神经纤维的变性、脱髓鞘改变等,从而导致相应部位的感觉、运动和神经反射功能的丧失。近年来,随着神经科学…     

嗅鞘细胞与脊髓损伤的治疗

摘要：嗅鞘细胞是一种特殊类型的神经胶质细胞,起源于嗅基底膜,分布在嗅球、嗅神经,并可伴随嗅神经轴突迁徙入脑。尽管目前嗅鞘细胞移植技术治疗脊髓损伤的疗效已经被大量基础实验证实,并且已经开始了初步的临床试验,但其在移植后作用的主要机制仍然需要继续探讨。脊髓的再生与修复是一个非常复杂的过程, 目前还有许多问题有待解决, 如嗅鞘细胞移植治疗的主要机制、嗅鞘细胞移植时机的选择、嗅鞘细胞纯度对移植效果的影响、嗅鞘细胞植入的方法等。     

嗅鞘细胞移植治疗脊髓损伤的临床研究现状

目的：对嗅鞘细胞生物学特性、培养纯化、嗅鞘细胞移植的可能机制及嗅鞘细胞移植在临床的应用等方面进行分析,介绍嗅鞘细胞移植治疗脊髓损伤的研究现状。 资料来源：以olfactory ensheathing cells,spinal cord injury,嗅鞘细胞,脊髓损伤为检索词检索PubMed数据库(2000/2009),中国期刊全文数据库(2000/2009)。 资料选择：纳入标准：①文章所述内容应与嗅鞘细胞及脊髓损伤密切相关。②同一领域选择近期发表或在权威杂志上发表的文章。排除标准：①重复性研究。②Meta分析。 结局评价指标：嗅鞘细胞移植治疗脊髓损伤的研究进展。 结果：嗅鞘细胞具有与许旺细胞和星形胶质细胞相似的特征。目前嗅鞘细胞移植的动物实验主要致力于提高轴突再生能力、替代细胞成分、阻止脱髓鞘病变和促进髓鞘再生等方面,移植的嗅鞘细胞具有促进感觉及运动功能恢复的客观结果,有些移植研究甚至已经进入了临床试验阶段。不过嗅鞘细胞移植由动物实验转化到临床应用还受到很多因素的影响,诸如移植剂量、细胞生长因子的活力,细胞移植的风险等,尤其是嗅鞘细胞移植后的近期及远期效果还需要进一步深入研究、评价,并且需要长时间的随访。有研究已经把用基因转染的嗅鞘细胞用于移植,在动物试验身上已经取得了满意的效果。 结论：随着基因工程技术发展以及嗅鞘细胞移植修复神经机制的深入研究,嗅鞘细胞移植必将为临床治疗脊髓损伤的患者带来康复的希望。     

嗅鞘细胞移植治疗晚期脊髓损伤临床试验初步报告

目的　开展嗅鞘细胞移植治疗晚期脊髓损伤的临床试验研究 ,探讨其移植是否安全可行 ,对晚期脊髓损伤患者是否有帮助脊髓神经功能恢复的作用。方法　取胚胎嗅球 ,消化成单个嗅鞘细胞后 ,培养 2～ 3周 ,然后将其移植到脊髓损伤部位的上下处。共治疗 171例伤后时间为 6个月至 18年 ,脊髓损伤部位没有压迫性病变的脊髓损伤患者 ,其中男 139例 ,女 32例 ,年龄为 2 .5～ 6 4岁。结果　嗅鞘细胞移植后两周～两个月时随访 ,按ASIA脊髓损伤神经功能分类国际标准评价 ,171例患者的脊髓功能均有部分恢复 ,其中运动功能由术前 34.5± 2 0 .3提高到 4 2 .0± 2 0 .0 ,轻触觉由术前 4 7.2± 2 4 .0提高到 6 1.8± 2 2 .9,痛觉由术前 4 8.6± 2 3.5提高到 6 4 .0± 2 2 .8。自身术前术后对照t检验 ,P <0 .0 0 1。患者无术后长期发热、脊髓感染和功能恶化等并发症 ,无与手术有关的死亡。结论　嗅鞘细胞移植安全可行 ,能帮助晚期脊髓损伤患者恢复部分脊髓神经功能。     

嗅黏膜嗅鞘细胞与肌基膜管联合移植修复脊髓损伤

目的：观察嗅黏膜来源的嗅鞘细胞与肌基膜管联合移植后对脊髓损伤的修复效果。 方法：1只SD大鼠行背正中切口，顺椎旁肌纤维切除约1.5 cm×0.8 cm×0.6 cm的肌条，复温、漂洗并挤压肌条以排出肌浆，制成肌基膜管。4只SD大鼠麻醉后取出嗅黏膜，胶原酶消化法分离培养嗅鞘细胞，调整浓度至1011 L-1。取SD大鼠50只，随机分成5组：嗅鞘细胞+肌基膜管联合组、嗅鞘细胞组、肌基膜管组、模型组、正常组，10只/组。除正常组外，其余组均建立脊髓损伤模型，于T10横断脊髓并切除约2 mm，将培养7 d的嗅鞘细胞与肌基膜管按组别分别植入脊髓断端，模型组用浸有DMEM的凝胶海绵桥接横断的脊髓。 结果：移植后第8周，嗅鞘细胞+肌基膜管联合组、嗅鞘细胞组大鼠运动功能明显恢复，出现大关节大幅度运动，且前者运动功能BBB评分升高尤为显著（P < 0.01）；肌基膜管组大鼠仅见小关节轻微活动；模型组大鼠后肢挛缩重，无明显功能恢复。嗅鞘细胞+肌基膜管联合组后肢体感诱发电位及运动诱发电位的潜伏期显著低于其他各组（P < 0.01）。苏木精-伊红染色和核转录因子免疫组化染色结果显示，嗅鞘细胞+肌基膜管联合组、嗅鞘细胞组的移植物与损伤脊髓整合较好，未见明显空洞，有大量染色呈阳性的纤维，纤维较长，由近侧端长入远侧端；肌基膜管组有空洞形成，染色阳性的纤维数量少，纤维细小且排列紊乱；模型组端断间充满瘢痕组织，未见明显染色阳性纤维。 结论：嗅鞘细胞移植可促进脊髓损伤后的轴突再生，肌基膜管作为一种生物管道，两者联合应用可明显促进脊髓损伤后的轴突再生及功能恢复。     

嗅鞘细胞静脉移植治疗脊髓损伤

背景：嗅鞘细胞移植治疗脊髓损伤在众多疗法中效果较佳,成为最有前景的治疗方法之一。目前移植方法为局部移植,存在操作复杂、创伤大、重复移植治疗困难等缺点。寻找一种简单易行且疗效好的移植方法成为各国学者研究的热点。 目的：分析嗅鞘细胞静脉移植治疗脊髓损伤的可行性和疗效。 方法：制备Wistar大鼠脊髓半切模型,随机分4组：嗅鞘细胞髓内局部移植组、嗅鞘细胞静脉移植组、D/F12静脉移植组和空白对照组。定期行CBS功能评分及组织学检查,评价脊髓修复情况。 结果与结论：嗅鞘细胞髓内局部移植组、嗅鞘细胞静脉移植组的功能恢复和组织学改变优于D/F12静脉移植组和空白对照组,嗅鞘细胞髓内局部移植组、嗅鞘细胞静脉移植组间无显著差别。说明嗅鞘细胞静脉移植可向脊髓损伤部位迁移并修复脊髓损伤,其疗效与嗅鞘细胞髓内局部移植相当。     

嗅鞘细胞移植后大鼠损伤脊髓神经生长因子的表达

目的 研究嗅鞘细胞移植对大鼠损伤脊髓内的神经生长因子(NGF)表达的影响,以从NGF角度探讨嗅鞘细胞移植修复大鼠脊髓损伤的机制.方法 48只SD大鼠用NYU -Ⅱ撞击机(10g-25 mm)损伤T10脊髓制作脊髓损伤(SCI)模型,随机分为嗅鞘细胞组、DMEM组各24只;另设立正常对照组6只.将GFP-嗅鞘细胞细胞悬液移植入嗅鞘细胞组大鼠损伤处,DMEM组用单纯的DMEM/F12液代替,正常对照组不做任何处理.移植术后1d、7d、14 d、21 d,用BBB评分法测定脊髓运动功能,RT - PCR方法比较各时间点NGF表达差异.移植术后第21天应用免疫组化比较嗅鞘细胞组、DMEM组、正常对照组大鼠脊髓损伤区NGF的表达差异.结果 移植后1d、7d、14 d、21 d,嗅鞘细胞移植组运动功能评分均高于同期DMEM组.NGF表达量在术后第1天最高,第7天达峰值,之后缓慢降低.移植后第21天,嗅鞘细胞移植组脊髓NGF表达量高于同期DMEM组和正常对照组.结论 嗅鞘细胞移植可上调损伤脊髓NGF的表达,从而促进了损伤脊髓的修复.     

嗅鞘细胞移植修复大鼠脊髓损伤的组织病理学变化☆

背景：对于脊髓损伤,目前临床尚无有效的治疗对策,近年来嗅鞘细胞移植对脊髓损伤修复取得了一定的进展。 目的：观察嗅鞘细胞移植在缓解损伤脊髓的病理反应和超微结构变化,及其在发生发展中的作用。 方法：60只大鼠随机分为空白组,模型组,嗅鞘胞移植组和DF12组,每组15只。空白组：仅切开T10全椎板及T9,T11部分椎板,对脊髓未作其他处理,明胶海绵轻柔压迫止血;模型组：仅切断脊髓,未作特殊处理;嗅鞘细胞移植组和DF12组：切断脊髓后用微量注射器分别注射嗅鞘细胞和DF12培养液,随后缝合切口。脊髓损伤后1,3,7,14,28,42,56 d每组麻醉2只受检大鼠,取材做光镜观察和电镜观察。 结果与结论：单纯脊髓横切损伤后,发生了出血、水肿、变性、坏死以及囊腔形成,胶质细胞增生和神经纤维再生。嗅鞘细胞移植后,明显减轻了神经元和神经纤维的坏死变性程度,减轻病理反应,并能对损伤神经元实施保护;防止了胶质细胞过度增生形成瘢痕屏障,明显增加了再生神经纤维的数量。提示嗅鞘细胞移植对损伤脊髓具有减轻病理反应和促进修复的作用。     

嗅鞘细胞移植脊髓损伤大鼠NG2的表达

背景：对于脊髓损伤,目前临床尚无有效的治疗对策,近年来嗅鞘细胞移植治疗脊髓损伤修复取得了一定的进展。NG2是主要的硫酸软骨素蛋白多糖分子,对轴突有抑制作用。 目的：观察嗅鞘细胞移植对脊髓损伤大鼠NG2表达的影响,进一步分析嗅鞘细胞移植在修复脊髓损伤中的作用途径。 方法：将112只大鼠随机分为4组,空白组、模型组、嗅鞘细胞移植组及DF12组各28只。空白组仅切开T10全椎板及T9,T11部分椎板,对脊髓未作其他处理;其他3组应用脊髓横切法制作脊髓损伤动物模型。嗅鞘细胞移植组进行嗅鞘细胞移植,每侧断端植入20 000 cells;DF12组于相同部位注射DF12培养液。在大鼠脊髓损伤后1,3,7,14,28,42和56 d时,取材按照SP试剂盒的操作步骤检测NG2的表达。 结果与结论：空白组NG2呈低表达,在模型组、DF12组脊髓损伤24 h后损伤部位的NG2的表达开始升高,7 d时达到顶点,4周时NG2表达明显降低,6,8周时仅在局部有所表达。嗅鞘细胞移植组脊髓损伤1 d时NG2表达开始增加,主要在损伤部位,在各时间点与模型组、DF12组相比NG2表达水平明显降低,但高于空白组NG2各时间点的表达。提示嗅鞘细胞移植后NG2的表达水平降低,嗅鞘细胞具有抑制NG2表达的作用,可消除或减轻细胞外基质中对轴突有抑制作用的化学屏障,这可能是其治疗脊髓损伤促进轴突再生的机制之一。     

移植时间对嗅鞘细胞移植治疗脊髓损伤效果的影响★

背景：嗅鞘细胞移植治疗陈旧性脊髓损伤的疗效可受多种影响因素如受伤的时间、节段、性别等的影响，而患者受伤后应在哪个时间段进行嗅鞘细胞移植目前尚无定论。 目的：关注嗅鞘细胞移植时间窗的选择对脊髓损伤患者运动和感觉功能恢复的影响。 设计：自身前后对照观察。 单位：泰安荣军医院神经外科。 对象：选择2004-06/2007-06山东省泰安荣军医院脊柱脊髓外科收治的脊髓损伤患者135例，其中男121例，女14例；年龄7~59岁，平均36岁。脊髓损伤时间：0~6个月21例，7个月~2年71例，2年以上43例。纳入患者或其（未成年）父母了解这一临床试验的特殊性和可能结果；患者或其监护人同意接受细胞移植治疗并签自愿接受协议书；实验和治疗方案符合中国卫生部（91-006）文件规定，经山东省泰安荣军医院伦理委员会批准。 方法：①将流产胚胎的嗅球消化成单个嗅鞘细胞后培养7~15 d待用。产妇同意提供流产胚胎用于实验，此方案经过医院伦理委员会批准。②患者全身麻醉后，借助显微镜将已培养好的嗅鞘细胞悬液采用多靶点注射的方法分别移植到相应的区域内。靶点的选择据损伤情况而定，一般位于损伤区域的上下两端及左右侧正常脊髓处。据损伤区域的大小决定靶点的多少，每个靶点注射细胞量约100万单位，悬液约50 μL，含量大约2×1010 L-1,一般为2~5个靶点。③于移植前及移植后2~8周按照美国脊髓损伤学会制定的美国脊髓损伤学会标准评估患者运动和感觉功能。 主要观察指标：美国脊髓损伤学会标准评分。 结果：脊髓损伤患者135例均进入结果分析。不同移植时间窗脊髓损伤患者运动和感觉功能均较移植前有明显提高，差异有非常显著性意义（P < 0.01）；不同移植时间窗患者移植后运动和感觉功能分数及分数提高程度比较，差异无显著性意义（P > 0.05）。 结论：嗅鞘细胞移植可促进脊髓损伤患者的神经功能恢复，且不存在移植时间窗差异。     

The importance of olfactory ensheathing cells for spinal cord injury

<正>We have been conducting clinical trials on olfactory ensheathing cell(OEC)transplantation for incomplete chronic spinal cord injury(SCI)since 2005.Long-term follow-up results verified that sensory and motor functions improved in most patients to varying degrees.However,the main source of OECs     

Transplantation of olfactory ensheathing cells for promoting regeneration following spinal cord injury

OBJECTIVE： To investigate the status of olfactory ensheathing cells （OECs） transplantation in facilitating the regeneration of spinal cord injury. DATA SOURCES： Articles about OECs transplantation in treating spinal cord injury were searched in Pubmed database published in English from January 1981 to December 2005 by using the keywords of ＂olfactory ensheathing cells, transplantation, spinal cord injury＂. STUDY SELECTION： The data were checked primarily, literatures related to OECs transplantation and the regeneration of spinal cord injury were selected, whereas the repetitive studies and reviews were excluded. DATA EXTRACTION： Totally 43 articles about OECs transplantation and the regeneration and repair of spinal cord injury were collected, and the repetitive ones were excluded. DATA SYNTHESIS： There were 35 articles accorded with the criteria. OECs are the olfactory ensheathing glias isolated from olfactory bulb and olfactory nerve tissue. OECs have the characters of both Schwann cells in central nervous system and peripheral astrocytes. The transplanted OECs can migrate in the damaged spinal cord of host, can induce and support the regeneration, growth and extension of damaged neuritis. Besides, transgenic technique can enable it to carry some exogenous genes that promote neuronal regeneration, and express some molecules that can facilitate neural regeneration, so as to ameliorate the internal environment of nerve injury, induce the regeneration of damaged spinal cord neurons, which can stimulate the regeneration potential of the damaged spinal cord to reach the purpose of spinal cord regeneration and functional recovery. CONCLUSION： OECs are the glial cells with the energy for growth at mature phase, they can myelinize axons, secrete various biological nutrition factors, and then protect and support neurons, also facilitate neural regeneration. OECs have been successfully isolated from nasal olfactory mucosa and olfactory nerve. Therefore, autologous transplantation of OECs and objective genes modified OECs carrying various neurotrophic factors may become an effective method to treat spinal cord injury in the future.     

Transplantation of olfactory ensheathing cells for promoting regeneration following spinal cord injury

OBJECTIVE: To investigate the status of olfactory ensheathing cells (OECs) transplantation in facilitating the regeneration of spinal cord injury. DATA SOURCES: Articles about OECs transplantation in treating spinal cord injury were searched in Pubmed database published in English from January 1981 to December 2005 by using the keywords of "olfactory ensheathing cells, transplantation, spinal cord injury". STUDY SELECTION: The data were checked primarily, literatures related to OECs transplantation and the regeneration of spinal cord injury were selected, whereas the repetitive studies and reviews were excluded. DATA EXTRACTION: Totally 43 articles about OECs transplantation and the regeneration and repair of spinal cord injury were collected, and the repetitive ones were excluded. DATA SYNTHESIS: There were 35 articles accorded with the criteria. OECs are the olfactory ensheathing glias isolated from olfactory bulb and olfactory nerve tissue. OECs have the characters of both Schwann cells in central nervous system and peripheral astrocytes. The transplanted OECs can migrate in the damaged spinal cord of host, can induce and support the regeneration, growth and extension of damaged neuritis. Besides, transgenic technique can enable it to carry some exogenous genes that promote neuronal regeneration, and express some molecules that can facilitate neural regeneration, so as to ameliorate the internal environment of nerve injury, induce the regeneration of damaged spinal cord neurons, which can stimulate the regeneration potential of the damaged spinal cord to reach the purpose of spinal cord regeneration and functional recovery. CONCLUSION: OECs are the glial cells with the energy for growth at mature phase, they can myelinize axons, secrete various biological nutrition factors, and then protect and support neurons, also facilitate neural regeneration. OECs have been successfully isolated from nasal olfactory mucosa and olfactory nerve. Therefore, autologous transplantation of OECs and objective genes modified OECs carrying various neurotrophic factors may become an effective method to treat spinal cord injury in the future.     

嗅鞘细胞移植损伤脊髓组织的超微结构变化

背景：脊髓损伤后神经功能难以自行恢复,嗅鞘细胞具有外周性和中枢性两种胶质细胞的成鞘功能,是修复受损神经最有前途的种子细胞。嗅鞘细胞移植到受损脊髓后的组织学和超微结构的变化可能帮助解释嗅鞘细胞发挥修复作用的机制。 目的: 验证嗅球源性嗅鞘细胞移植对脊髓损伤功能恢复的促进作用,并观察移植的嗅鞘细胞对神经元和轴突组织和超微结构的影响。 方法：将已制备脊髓模型的Wistar大鼠随机分为3组,对照组不做任何注射操作,DMEM/F12组注射DMEM/F12培养基,嗅鞘细胞组注射嗅鞘细胞悬液。每周进行肢体活动BBB评分,8周后取脊髓标本进行组织学和免疫组织化学观察,评价脊髓损伤的修复情况,并观察嗅鞘细胞移植对脊髓组织和超微结构的影响。 结果与结论：3组动物均出现后肢运动功能的恢复,嗅鞘细胞组优于对照组和DMEM/F12组,在4周后更为明显。组织学观察可见,在嗅鞘细胞组可见有神经纤维通过损伤处。损伤处附近,嗅鞘细胞组脊髓腹侧的神经纤维和神经元形态较好,损伤较轻。而对照组和DMEM/F12组神经纤维和神经元损害严重。嗅鞘细胞组的caspsase-3阳性细胞数少于对照组和DMEM/F12组。超微结构观察可见,嗅鞘细胞组的神经纤维和细胞形态均优于对照组和DMEM/F12组。结果表明嗅鞘细胞移植对大鼠脊髓损伤修复有明显的促进作用,并可恢复损伤神经的部分功能,对受损神经纤维和神经元有保护作用。     

Cell therapy for spinal cord injury with olfactory ensheathing glia cells (OECs)

The prospects of achieving regeneration in the central nervous system (CNS) have changed, as most recent findings indicate that several species, including humans, can produce neurons in adulthood. Studies targeting this property may be considered as potential therapeutic strategies to respond to injury or the effects of demyelinating diseases in the CNS. While CNS trauma may interrupt the axonal tracts that connect neurons with their targets, some neurons remain alive, as seen in optic nerve and spinal cord (SC) injuries (SCIs). The devastating consequences of SCIs are due to the immediate and significant disruption of the ascending and descending spinal pathways, which result in varying degrees of motor and sensory impairment. Recent therapeutic studies for SCI have focused on cell transplantation in animal models, using cells capable of inducing axon regeneration like Schwann cells (SchCs), astrocytes, genetically modified fibroblasts and olfactory ensheathing glia cells (OECs). Nevertheless, and despite the improvements in such cell‐based therapeutic strategies, there is still little information regarding the mechanisms underlying the success of transplantation and regarding any secondary effects. Therefore, further studies are needed to clarify these issues. In this review, we highlight the properties of OECs that make them suitable to achieve neuroplasticity/neuroregeneration in SCI. OECs can interact with the glial scar, stimulate angiogenesis, axon outgrowth and remyelination, improving functional outcomes following lesion. Furthermore, we present evidence of the utility of cell therapy with OECs to treat SCI, both from animal models and clinical studies performed on SCI patients, providing promising results for future treatments.