小鼠胚胎神经干细胞海马移植对APP/PS1双转基因AD小鼠的治疗作用

目的 在APP/PS1双转基因阿尔茨海默病(Alzheimer disease, AD)小鼠观察神经干细胞(nerual stem cells, NSCs)移植后细胞的存活、迁移以及对小鼠记忆功能的影响.方法 增强型绿色荧光蛋白(enhanced green fluorescent protein, EGFP)质粒转染培养胚胎NSCs,小鼠海马内移植,水迷宫实验检测小鼠认知功能.结果 EGFP转染NSCs海马内移植2个月后可观察到GFP阳性细胞,大部分分布在针道附近,部分向同侧皮层迁移,亦有部分通过胼胝体向对侧大脑迁移,同时小量细胞发出类似于神经元的长突起.AD小鼠的记忆功能明显改善.结论 胚胎NSCs海马内移植后能存活、迁移并分化为神经组织细胞,并能显著改善APP/PS1双转基因AD小鼠的认知功能障碍.     

BDNF基因转染神经干细胞移植脑损伤大鼠移植细胞存活率和Trkβ、Erk1/2、Ras及Trx的表达

目的：探讨脑源性神经营养因子基因修饰神经干细胞（ BDNF／NSCs）移植大鼠创伤性脑损伤（ TBI）模型后,对移植细胞存活数量的影响及其机制。方法采用Feeney法制备TBI模型,于造模后72 h,随机分为两组：BDNFN／SCs 移植组及NSCs移植组,将3μL（1×108／mL）BDNF／NSCs或NSCs直接移植于脑损伤区。分别于移植后1、2、3和4周取脑组织,冻存或制备冰冻切片。在荧光显微镜下计数移植细胞存活数量,并采用免疫组织化学技术检测p－Erk1／2、Ras蛋白的表达;通过RT－PCR技术检测脑损伤区及周围组织中Trx、Trkβ基因的表达。结果 BDNF／NSCs组和NSCs 组细胞存活数随移植时间延长而减少,在移植后的不同时间点,BD-NF／NSCs组移植细胞存活率均明显高于NSCs 组（P＜0．05）;BDNF／NSCs组在移植后不同时间点移植细胞的p－Erk1／2、Ras蛋白表达强度均明显高于NSCs组（P＜0．05）;与NSCs组比较,BDNF／NSCs组损伤灶及周围脑组织中Trx、Trkβ基因的表达水平均明显增强（ P＜0．05）。结论 BDNF基因转染NSCs移植大鼠TBI后,能够明显提高移植细胞的存活率,上调Trkβ、p－Erk1／2、Ras及Trx的表达。 BDNF与其受体Trkβ结合后,可能通过Ras／Raf／Erk途径激活其下游的Trx基因从而激活细胞的抗氧化作用,进而减少移植细胞的氧化损伤,提高移植细胞在脑组织损伤区的存活率。     

神经干细胞经尾静脉移植后在阿尔茨海默病鼠脑组织中的分布

目的 观察移植的神经干细胞能否顺利通过阿尔茨海默病（AD）转基因小鼠的血脑屏障,以及进一步在其脑内存活与迁徙的规律。方法体外分离培养获得神经干细胞,绿色荧光蛋白标记后通过AD鼠尾静脉移植,在移植后48h,1周、2周,1个月分别取脑连续冰冻切片,荧光显微镜下观察移植细胞的分布以及迁移情况。结果在移植后的不同时间点,脑内均可见到散在分布绿色荧光蛋白阳性细胞,48h内以血管周围分布较为常见,随时间延长至4周,海马和脑皮质中也可见弥散分布。而接受移植的小鼠4周内生长发育良好,未见到有成瘤现象发生。结论神经干细胞能够顺利通过阿尔茨海默病转基因小鼠的血脑屏障,在其脑中弥散分布并随时间发生迁移。     

BDNF-GFP转染神经干细胞对脊髓损伤大鼠BDNF表达的影响

目的探讨脑源性神经营养因子（Brain-Derived Neurotrophic Factor,BDNF）和绿色荧光蛋白（Green Fluorescent Protein,GFP）转染后神经干细胞（Neural Stem Cells,NSCs）移植对脊髓损伤大鼠BDNF表达的影响。方法以携带BDNF-GFP基因的腺病毒转染NSCs,免疫组化及Western blot检测转染后NSCs BDNF表达。40只Wistar大鼠中假手术组8只,32只大鼠制成T9左侧横断模型,并随机分成四组：BDNF和GFP修饰的N-SCs移植组、GFP修饰的NSCs移植组、单纯NSCs移植组和模型组。在各NSCs移植组,脊髓损伤后向横断处显微注射等体积细胞,模型组在相同的部位注射等体积的PBS。实时定量PCR检测各实验组BDNF表达情况。结果免疫组化显示BDNF-GFP转染的NSCs可表达BDNF（黄色荧光）。Western blot结果显示BDNF-GFP转染的NSCs可表达相对分子质量约为41kU的融合蛋白条带。NSCs移植可使BDNF的表达量明显增高（P〈0.05或P〈0.01）,以BDNF-GFP转染的NSCs移植组BDNF表达量最高（P〈0.01）。结论 BDNF-GFP转染后NSCs可在脊髓半切模型中存活并高表达具有生物活性的BDNF。     

腺病毒载体Ad-BDNF-EGFP的构建和在神经干细胞中的表达

目的研究腺病毒载体Ad-BDNF-EGFP的构建及其在神经干细胞(NSCs)中的表达。方法通过RT-PCR从大鼠海马中获得BDNF基因,通过基因克隆、HEK293包装,获得含增强绿色荧光蛋白基因的重组腺病毒表达载体pAd-BDNF-EGFP,将其感染原代培养的神经干细胞,观察EGFP及BDNF2种基因的表达,镜下测定转染率,并检测RT-PCR产物,证实BDNF的存在。转染后的神经干细胞经G418筛选,抗性细胞传代扩增后获得成功转染BDNF基因的NSCs克隆。结果荧光显微镜下可见感染后的NSCs表达EGFP而发出绿色荧光;通过RT-PCR证明感染后的NSCs具有表达BDNF的能力;用ELISA鉴定细胞上清中分泌的BDNF,72h的含量达到最高值,为12.78ng/mL;证明通过构建病毒的感染可以使神经干细胞获得分泌BDNF的能力,且EGFP基因可作为神经干细胞移植研究中良好的示踪剂。结论腺病毒病毒介导EGFP基因及BDNF基因在大鼠胚胎神经干细胞中成功表达,为应用以神经干细胞直接作为基因靶细胞,介导基因治疗中枢神经系统疾病奠定了基础。     

福建省多层次养老服务供求现状及对策研究

目的 研究氯化锂对移植到胫神经内的神经干细胞的存活、分化的影响;研究神经干细胞移植和氯化锂处理对宿主神经轴突溃变、炎症细胞浸润的影响.方法 结扎成年大鼠右侧胫神经,将培养的神经干细胞注射到结扎部位远端,腹腔注射氯化锂或生理盐水,1周后用免疫荧光染色方法检测神经干细胞的巢蛋白(Nestin)、神经核抗原(NeuN)、胆碱乙酰转移酶(ChAT)、胶质细胞原纤维酸性蛋白质(GFAP)、神经纤丝蛋白200(NF200)、巨噬细胞抗原(ED1)的表达情况.结果 移植到胫神经内的神经干细胞存活良好,并沿神经轴索间隙向周围扩散.移植后的神经干细胞未见Nestin阳性表达,大部分移植细胞呈GFAP阳性表达,无NeuN或ChAT阳性表达.腹腔注射氯化锂能显著减少移植细胞的GFAP阳性表达比例.胫神经结扎后,神经内轴突溃变明显.与未移植神经干细胞组比较,移植组胫神经内NF200阳性表达明显增多,联合应用氯化锂能进一步增加NF200的表达.应用氯化锂能显著减少神经干细胞移植后胫神经内的ED1表达.结论 氯化锂能减少移植后的神经干细胞向胶质细胞方向的分化,神经干细胞移植联合应用氯化锂可以减少宿主神经轴突的溃变程度,同时能抑制神经干细胞移植后的炎症细胞浸润.     

大鼠脊髓损伤BDNF基因修饰神经干细胞移植后HRP逆行示踪

目的：检测大鼠脊髓损伤脑源性神经营养因子（Brain-derived neurotrophic factor,BDNF)基因修饰神经干细胞移植后，神经纤维的再通及后肢功能恢复情况。方法：大鼠L4脊髓全横断后，在横断处立即移植BDNF基因修饰神经干细胞，分四个时相点（1周，1、2、3个月）进行辣根过氧化物酶（HRP）逆行示踪，并观察损伤移植处的形态学变化及大鼠后肢运动功能恢复情况。结果：损伤移植处脊髓的形态学明显好转；损伤移植处上段脊髓中，移植1个月组有HRP阳性细胞，以后两组逐渐增多；移植组大鼠后肢运动功能明显恢复。结论：大鼠脊髓损伤BDNF基因修饰神经干细胞移植后，在损伤移植处有HRP阳性神经元和神经纤维，大鼠后肢运动功能明显恢复，提示BDNF基因修饰神经干细胞有修复大鼠脊髓损伤的作用。     

转基因神经干细胞移植治疗暂时性脑缺血的实验研究

目的探讨转染血管内皮细胞生长因子(VEGF)基因的神经干细胞在宿主缺血区的基因表达情况,以及对神经功能的保护作用.方法用脂质体介导法将VEGF121基因转染到大鼠神经干细胞中.经RT-PCR及免疫荧光染色检测转基因神经干细胞及其分化细胞的基因表达情况.建立大鼠大脑中动脉梗塞模型(tMCAO),并将其随机分成(1)对照组,(2)细胞悬液PBS移植组,(3)神经干细胞移植组,(4)转基因神经干细胞移植组,前3组每组10只大鼠,第4组20只大鼠.立体定向法将BrdU标记的转基因神经干细胞移植到tMCAO大鼠的纹状体缺血半暗区.移植后2～12周进行神经损害严重程度评分(NSS)并与其他3组比较.用免疫荧光染色方法观察移植后1周转基因神经干细胞在脑内的基因表达情况和移植后12周转基因神经干细胞在脑内的分化、迁徙情况.结果转基因神经干细胞及其分化的子代细胞均有VEGF121的表达并持续2周左右.移植后2、4、6、8、10、12周(4)组大鼠的NSS评分分别为5.8±1.5、5.0±1.0、4.6±1.0、4.0±0.7、4.0±1.0、3.8±0.4,均低于其他3组.其中第8周显著低于(1)、(2)组(均P=0.008),第12周显著低于(1)、(2)、(3)组(均P=0.000).转基因神经干细胞移植后1周在宿主脑内迁徙并表达VEGF基因产物,移植后12周在宿主脑内存活、迁徙,部分分化成神经元.结论转染VEGF基因的神经干细胞移植后在缺血早期表达基因产物,并对宿主局部血管和神经结构具有保护作用.转基因神经干细胞移植是治疗脑缺血性疾病的可行途径.     

移植诱导中脑NSCs分化的多巴胺能神经元对PD大鼠治疗作用的实验研究

目的研究移植诱导中脑神经干细胞分化出的多巴胺能神经元对PD大鼠的治疗作用.方法利用纹状体提取液诱导大鼠胚胎中脑神经干细胞,使其部分分化为酪氨酸羟化酶(TH)阳性的多巴胺能神经元,继而把分化后的细胞移植到PD大鼠的纹状体内,免疫组化法证实移植细胞的存活并以诱发旋转行为的改善来观察其治疗作用.结果纹状体提取液能够诱导中脑神经干细胞分化出多巴胺能神经元而且这种经诱导后产生的细胞能够在PD大鼠体内长期存活并改善阿卟吗啡诱导的旋转行为.结论诱导中脑神经干细胞分化出的多巴胺能神经元对PD有一定的治疗作用.     

人类神经前体细胞大鼠胎脑内移植研究

目的探讨人类神经前体细胞大鼠胎脑侧脑室内移植后的移行和分布。方法采用机械方法从胎脑中分离神经细胞,应用N2培养基进行培养,细胞用携带LacZ基因的腺病毒或BrdU标记,移植到孕期为16~18d的胎鼠侧脑室内,检查出生后不同时期脑组织中移植细胞的分布和移行。结果成功培养出人类的神经干细胞,细胞聚集形成神经球,呈悬浮状态,大部分细胞表达神经前体细胞的标志物巢蛋白,这种细胞能够分化为神经元、星型胶质细胞和少突胶质细胞。神经干细胞在体内和体外可以稳定表达外源性基因,移植到胎鼠脑内,人类胚胎神经前体细胞广泛移行并分布于宿主的脑组织中,结合到大鼠的前脑、中脑和后脑,形成广泛的嵌合现象。结论神经干细胞可以稳定表达外源性基因,移植到发育期的脑内,能够整合到脑组织中,形成广泛的嵌合现象。     

Magnetic Resonance Imaging of Transplanted Neural Stem Cells in Parkinson Disease Rats

Parkinson's disease (PD) is a degeneration disease with a main pathological change of characteristic deletion of nigra dopaminergic neurons. Now it is well known that neural stem cells (NSCs) reside in specific mammal brain region[1]. NSCs are optimal for cell-replacement therapy, thus making it a complementary therapeutic strategy to the traditional pharmacological therapies and fetal mesencephalic tissues transplantation[2]. It is important to distinguish grafted NSCs from host brain cel…     

Experimental Study of Cell Migration and Functional Differentiation of Transplanted Neural Stem Cells Co-labeled with Superparamagnetic Iron Oxide and Brdu in an Ischemic Rat Model

Objective To explore the migration of transplanted neural stem cells co-labeled with superparamagnetic iron oxide （SPIO） and bromodeoxyuridine （Brdu） using the 4.7T MR system and to study the cell differentiation with immuno-histochemical method in ischemic rats. Methods Rat neural stem cells （NSCs） co-labelled with SPIO mediated by poly-L-lysine and bromodeoxyuridine （BrdU） were transplanted into the unaffected side of rat brain with middle cerebral artery occlusion （MCAO）. At weeks 1, 2, 3, 4, 5, and 6 after MCAO, migration of the labelled cells was monitored by MRI. At week 6 the rats were killed and their brain tissue was cut according to the migration site of transplanted ceils indicated by MRI and subjected to Prussian blue staining and immunohistochemical staining to observe the migration and differentiation of the transplanted NSCs. Results Three weeks after transplantation, the linear hypointensity area derived from the migration of labelled NSCs was observed by MRI in the corpus callosum adjacent to the injection site. Six weeks after the transplantation, the linear hypointensity area was moved toward the midline along the corpus callosum. MRI findings were confirmed by Prussian blue staining and immunohistochemical staining of the specimen at week 6 after the transplantation. Flourescence co-labelled immunohistochemical methods demonstrated that the transplanted NSCs could differentiate into astrocytes and neurons. Conclusion MRI can monitor the migration of SPIO-labelled NSCs after transplantation in a dynamical and non-invasive manner. NSCs transplanted into ischemic rats can differentiate into astrocytes and neurons during the process of migration.     

携带脑源性神经营养因子基因人脐带干细胞改善脑损伤大鼠神经功能的实验研究

目的 研究携带脑源性神经营养因子(BDNF)基因的人脐带间充质干细胞(UCMSC)脑内移植对脑损伤大鼠神经行为学恢复的影响.方法 建立大鼠自由落体颅脑损伤动物模型;培养纯化UCMSC,构建BDNF-pcDNA3重组质粒载体,并转染UCMSC;体外检测UCMSC携带BDNF基因的表达水平,并进行生物活性分析.将成功表达BDNF的UCMSC移植入大鼠损伤局部脑组织.2周进行神经功能缺损评分,探讨BDNF转基因UCMSC移植对脑损伤大鼠神经行为学的影响.结果 大鼠脑损伤后2周,神经功能[(10.50±0.53)分]障碍明显.UCMSC在损伤脑区存活,迁移;BDNF转基因UCMSC移植后神经功能[(5.50±0.76)分]与单纯UCMSC移植组[(7.75±0.71)分]比较明显改善,差异有统计学意义(P＜0.01).结论 携带BDNF基因的UCMSC脑内移植对脑损伤大鼠神经行为学恢复有明显促进作用.

Abstract：

Objective To explore the effect of brain derived neurtrophic factor(BDNF) gene modified umbilical cord mesenchymal stem cells ( UCMSC ) transplantation on neurological functional improvement in rats after brain trauma.Methods Cerebral contusion model in motor-sensory cortex in rats was established by a weight hammer falling method.UCMSC were cultured and transferred with BDNF gene.After BDNF expression and activity were determined,the BDNF gene modified UCMSC were implanted into traumatic brain.The neurological function was evaluated for 2 weeks after brain injury.And the BDNF expression was determined by using immunohistochemistry.Results Severe neurological dysfunction was seen in animals that had been subjected to contusion brain injury( 10.50 ±0.53 ).A significant improvement on neurological function was found in the UCMSC transplantaion animal( 7.75 ± 0.71 ), compared with only brain injury group (P ＜ 0.01 ).Moreover, rats in BDNF gene modified UCMSC showed the most behavior improvement ( 5.50 ± 0.76 ) (P ＜ 0.01 ).Conclusion BDNF gene modified UCMSC transplantation can survive and migrate, and improve neurological function in brain traumatic rats.     

神经干细胞在海人酸毁损大鼠海马中的迁移和分化

目的：观察胎鼠神经干细胞移植入海人酸毁损成年大鼠海马中的迁移和分化情况。方法：体外培养胎鼠海马源性神经干细胞。立体定位注射海人酸毁损大鼠海马CA1区锥体细胞。毁损1周后，将Hoechst33342标记的神经干细胞移植毁损区．分别于术后1、2,4、8周取材，利用荧光技术和免疫组织化学方法，追踪移植的神经干细胞在毁损侧海马中的存活、迁移和分化情况。结果：移植的神经干细胞在海马锥体层呈链状迁移，并分化为MAP2阳性细胞和GFAP阳性细胞。结论：移植的神经干细胞在海马锥体层呈链状迁移。大部分分化为胶质细胞。     

绿色荧光蛋白转基因小鼠神经干细胞移植对海仁藻酸致SD大鼠小脑变性损害的实验研究

目的通过观察绿色荧光蛋白(GFP)转基因小鼠神经干细胞(NSCs)移植对海仁藻酸(KA)致SD大鼠小脑变性损害区的存活、迁移情况,为临床上NSCs移植治疗小脑变性提供理论依据。方法SD大鼠40只随机分为正常对照组(A组),KA损伤未移植组(B组),KA损伤后注射生理盐水组(C组),KA损伤后NSCs移植组(D组)。分离、培养GFP转基因小鼠的NSCs,以立体定向微量注射方法移植至KA致小脑变性损害区,进行行为学、免疫组化研究。结果(1)行为学观察:A组大鼠头部及口鼻呈机敏的探索状,四肢及躯干动作协调,尾巴稍抬高,可左右摆动。B组和C组表现为精神差,厌食,少动,行动摇晃迟缓,身体左右摇晃,头部触地,尾巴拖地,多次侧翻跌倒并自己不能翻正,嘴部寻找食物笨拙,过竿时间较A组明显延长。D组行为学表现及过竿时间较A组差,但优于B、C组,差异有统计学意义(P<0.05)。(2)免疫组化发现NSCs在小脑变性区存活和迁移,未见细胞过度增生。植入细胞存活数随时间延长而减少,7 d、14 d、28 d分别为(102±67)、(58±77)、(24±6)个/HP,差异有统计学意义(P<0.01)。结论NSCs在小脑变性损害区能够存活、迁移,能够改善KA致小脑变性共济失调症状,提示NSCs移植可成为治疗小脑变性损害的治疗手段。     

Induction of functional recovery by co-transplantation of neural stem cells and Schwann cells in a rat spinal cord contusion injury model

Objective To study the transplantation efficacy of neural stem cells （NSCs） and Schwann cells （SC） in a rat model of spinal cord contusion injury. Methods Multipotent neural stem cells （NSCs） and Schwann cells were harvested from the spinal cords of embryonic rats at 16 days post coitus and sciatic nerves of newborn rats, respectively. The differential characteristics of NSCs in vitro induced by either serum-based culture or co-culture with SC were analyzed by immunofluorescence. NSCs and SCs were co-transplanted into adult rats having undergone spinal cord contusion at T9 level. The animals were weekly monitored using the Basso-Beattie-Bresnahan locomotor rating system to evaluate functional recovery from contusion-induced spinal cord injury. Migration and differentiation of transplanted NSCs were studied in tissue sections using immunohistochemical staining. Results Embryonic spinal cord-derived NSCs differentiated into a large number of oligodendrocytes in serum-based culture upon the withdrawal of mitogens. In cocultures with SCs, NSCs differentiated into neuron more readily. Rats with spinal cord contusion injury which had undergone transplantation of NSCs and SCs into the intraspinal cavity demonstrated a moderate improvement in motor functions. Conclusions SC may contribute to neuronal differentiation of NSCs in vitro and in vivo. Transplantation of NSCs and SCs into the affected area may be a feasible approach to promoting motor recovery in patients after spinal cord injury.     

移植的神经干细胞在脑损伤区壳聚糖载体中的存活与分化

目的:探讨移植的NSCs在大鼠脑损伤区壳聚糖载体中的存活、分化情况及其对TBI大鼠认知功能的影响。方法:低温冷冻干燥法制备壳聚糖多孔支架。将从鼠胚前脑中分离的NSCs扩增、标记BrdU。Feeney法制备SD大鼠TBI模型,随机分为3组:损伤对照组清创后不做移植;NSCs 支架移植组行壳聚糖作载体的NSCs移植;NSCs 支架 NGF移植组行壳聚糖作载体的NSCs移植,并在其中加入NGF。术后1、2、3个月行避暗回避和跳台试验。脑切片行Nissl染色、BrdU与NF-200免疫荧光双标染色。结果:两移植组的认知功能在术后1、2、3个月较损伤对照组明显改善,含NGF的移植组改善更加显著。两移植组术后1、2、3个月在移植区均可见BrdU与NF-200免疫荧光双标细胞,含NGF移植组中的双标细胞数量多、胞体大、突起多且长。结论:大鼠TBI后移植的外源性NSCs可以在脑损伤区壳聚糖载体中长期存活并向神经元分化,可以改善大鼠的认知功能;NGF对其具有促进作用。     

转染脑源性神经营养因子的骨髓间充质干细胞移植治疗大鼠脑缺血损伤的实验研究

目的： 探讨移植转染脑源性神经营养因子(brain-derived neurotrophic factor, BDNF)基因的大鼠骨髓间充质干细胞(mesenchymal stem cells,MSCs)在宿主脑缺血区的基因表达情况,以及对神经损伤的修复作用。方法： 将pcDNA 3.1-BDNF转染到大鼠MSCs中,并检测其表达情况。建立大鼠大脑中动脉梗塞(middle cerebral artery occlusion,MCAO)模型,并将大鼠随机分成对照组、PBS移植组、MSCs移植组和转基因MSCs移植组,每组均8只。将PBS悬液、5-溴脱氧尿嘧啶核苷(bromodeoxyuridine,BrdU)标记的MSCs悬液、BrdU标记的转基因MSCs悬液分别移植到PBS移植组,MSCs移植组和转基因MSCs移植组大鼠的纹状体缺血区半暗带,对照组不移植。移植后1～30 d对各组大鼠进行神经损害严重程度评分(neurological severity score, NSS)并相互比较。移植后30 d,检测各组大鼠脑缺血区BDNF、神经元特异性烯醇化酶(neuron specific enolasw,NSE)和胶质纤维酸性蛋白(glial fibrillary acidic protein,GFAP)的表达情况。结果： 大鼠脑缺血区移植转基因MSCs 24 h后,检测到BDNF的表达。移植后1 d各组NSS评分无显著差异,移植后7、14、21、30 d均显示转基因MSCs移植组低于其他组。移植后30 d, 转基因MSCs组BDNF阳性细胞数较MSCs组明显增多;NSE、GFAP阳性细胞数较其他组显著增多。结论： 大鼠脑缺血区移植转基因MSCs后表达基因产物,同时其表达的NSE、GFAP蛋白增加,对宿主的神经损伤具有修复作用。转染BDNF基因的MSCs移植是治疗脑缺血性疾病的可行途径。     

Functional recovery following traumatic spinal cord injury mediated by a unique polymer scaffold seeded with neural stem cells and Schwann cells

Background The most important objective of transplant studies in the injured spinal cord has been to provide a favorable environment for axonal growth. Moreover, the continuing discovery of new grafts is providing new potentially interesting transplant candidates. Our purpose was to observe the morphological and functional repair effects of the co-transplantation of neural stem cell （NSC）, Schwann ceils （SCs） and poly lactide-co-glycolide acid （PLGA） on the spinal cord injury of rats.Methods A scaffold of PLGA was fabricated. NSCs and SCs were cultured, with the NSCs labeled with 5-bromodeoxyuridine, and the complex of NSC/PLGA or NSC＋SCs/PLGA were constructed. Thirty-six Wistar rats were randomly divided into three groups： group A （transplantation of PLGA）, group B （transplantation of NSC/PLGA） and group C （transplantation of NSC＋SCs/PLGA）. The 3 mm length of the right hemicord was removed under the microscope in all rats. The PLGA or the complex of PLGA-celIs were implanted into the injury site. Basso-Beattie-Bresnahan （BBB）locomotion scores, motor and somatosensory evoked potential of lower limbs were examined to learn the rehabilitation of sensory and motor function at 4 weeks, 8 weeks, 12 weeks and 24 weeks after injury. All the recovered spinal cord injury （SCI） tissues were observed with HE staining, immunohistochemistry, and transelectronmicroscopy to identify the survival, migration and differentiation of the transplanted cells and the regeneration of neural fibres at 4 weeks, 8 weeks,12 weeks and 24 weeks after injury.Results （1） From 4 weeks to 24 weeks after injury, the BBB locomotion scores of cell-transplanted groups were better than those of the non-cell-transplanted group, especially group C （P 〈0.05）. The amplitudes of the somatosensory evoked potential （SEP） and motor-evoked potential （MEP） were improved after injury in groups B and C, but the amplitude of SEP and MEP at 4 weeks was lower than that at 12 weeks and 24 weeks after injury. Compared with group B, the amplitude of SEP and MEP in group C was improved. The amplitude of SEP and MEP was not improved after injury in group A. （2） HE staining revealed the volume of the scaffold decreased and the number of cells in the scaffold increased. Newly-grown capillaries also could be seen. Immunohistochemistry staining showed the transplanted NSCs could survive and migrate until 24 weeks and they could differentiate into neurons and oligodendrocytes. The regenerated axons were observed in the scaffold-cell complex with transelectronmicroscopy. The above manifestations were more extensive in group C.Conclusions The transplanted NSC can survive and migrate in the spinal cord of rats up to 24 weeks after injury, and they can differentiate into various neural cells. Co-transplantation of cells/PLGA can promote the functional recovery of the injured spinal cord. The effect of co-transplanting NSC＋SCs/PLGA is better than transplanting NSC/PLGA alone.     

脂肪组织的干细胞作为神经系统基因治疗载体的研究

目的观察大鼠脂肪组织源性基质细胞表达外源基因的能力和脑内移植后的分布,以获取基因治疗自体移植的载体细胞。方法腺病毒载体Ad5βgal介导法将LacZ转入培养的大鼠脂肪组织源性基质细胞。Hoechst33258标记细胞,立体定向移植到大鼠的纹状体,脑组织切片,在荧光显微镜下检查存活的细胞。结果脂肪组织源性基质细胞能够在体内和体外稳定表达LacZ基因,细胞移植到脑内可以移行,移植细胞没有过渡增生和肿瘤形成,对宿主脑组织无破坏。结论脂肪组织源性基质细胞可以稳定表达夕J源基因,与脑组织有很好的相容性,是中枢神经系统基因治疗的良好载体。