人胚胎脑海马区神经前体细胞移植到损伤的成年大鼠脑内存活及迁移的研究

本文从人胚胎脑海马区分离、培养、鉴定了神经前体细胞(neuralprecursorcells,NPCs),并初步观察了大鼠纹状体海人酸(kainicacid,KA)损伤后,人神经前体细胞(hNPCs)移植到成年大鼠侧脑室和纹状体后存活和迁移的情况。取胎龄8~12周的人胚胎脑海马区细胞,用含人表皮生长因子(humanepidermalgrowthfactor,h-EGF)、人碱性成纤维细胞生长因子(humanbasicfi-broblastgrowthfactor,h-bFGF)以及人白细胞抑制因子(humanleukemiainhibitorygrowthfactor,h-LIF)的DMEM/F12培养液离体培养,以含1%胎牛血清(fetalbovineserum,FBS)的DMEM/F12诱导分化,巢蛋白(nestin)免疫荧光染色鉴定NPCs的特征。向成年大鼠右侧纹状体内立体定位注射KA,造成大鼠纹状体局部损伤。用溴脱氧尿嘧啶核苷(bromodeoxyuridine,BrdU)体外标记第2代hNPCs,48h后分别移植到正常成年大鼠和损伤大鼠手术侧的侧脑室和纹状体。6周后用抗BrdU抗体检测HNPCs的存活和迁移。结果显示:体外培养呈悬浮球状生长的细胞是nestin阳性的hNPCs。hNPCs移植6周后,在大鼠损伤侧的纹状体和侧脑室内,均检测到了BrdU阳性细胞,并有一部分细胞迁移到了周围纹状体实质和胼胝体。结果提示:体外分离培养的hNPCs移植到成年大鼠脑损伤区周围可以存活和迁移,损伤区域可能对移植细胞的迁移有一定的诱向作用。     

大鼠胚胎神经上皮细胞脑内移植治疗帕金森病的实验研究

目的 观察大鼠胚胎神经上皮细胞植入帕金森病大鼠纹状体后的存活、分化情况及治疗作用。方法 孕11d大鼠剖腹取胚胎，剥离神经管，胰酶消化后获取神经管壁上的神经上皮细胞，在脑立体定位仪下植入帕金森病大鼠毁损侧纹状体内，于移植后不同时间诱发旋转实验，观察症状的改善，并灌注取脑，切片后做酪氨酸羟化酶(TH)免疫组织化学染色，检测胚胎神经上皮细胞的存活及分化状况。结果 胚胎神经上皮细胞脑内移植后，帕金森病鼠的旋转行为有明显改善。移植后2、4及8周时可检测到成片或散在的TH-免疫阳性细胞。结论 胚胎神经上皮细胞移植至帕金森病大鼠纹状体后，可分化为多巴胺能神经元并能改善旋转症状。     

脑内移植间充质干细胞治疗大鼠帕金森病模型的研究

目的研究大鼠骨髓间充质干细胞(MSCs)脑内移植治疗帕金森病(PD)大鼠的可行性。方法贴壁培养法分离、培养大鼠骨髓MSCs。将BrdU标记的第3代MSCs移植到PD大鼠纹状体内,移植后1、2和4周检测PD大鼠的行为学变化,应用BrdU免疫荧光观察移植细胞在脑内的存活情况,应用免疫组化法检测酪氨酸羟化酶(TH)在移植细胞及黑质的表达。结果移植细胞后1周、2周和4周PD大鼠与移植前相比行为学有改善,旋转圈数明显减少(P<0.05);PD大鼠损毁侧和健侧黑质内TH阳性细胞数之比随移植时间的延长而增加,但未发现移植细胞呈现TH阳性表达。细胞移植后1周、2周和4周检测均可见纹状体内BrdU阳性细胞散在分布。结论植入脑内的MSCs能够生存和迁移,MSCs脑内移植对PD大鼠有一定的治疗作用。     

中脑神经干细胞和骨髓基质干细胞对帕金森大鼠行为学及脑组织形态学的影响

背景：研究发现神经干细胞或者骨髓基质干细胞可脑内移植治疗中枢神经系统疾病,但是两种干细胞移植治疗效果的比较相对较少。目的：观察比较中脑神经干细胞和骨髓基质干细胞对帕金森大鼠行为学及脑组织形态学的影响。方法：58只SD大鼠构建帕金森病模型,随机分为3组,分别为骨髓基质干细胞组(20只)、中脑神经干细胞组(20只)、生理盐水组(18只)。造模成功后3周,选取右侧纹状体 2 个坐标点注入骨髓基质干细胞悬液、中脑神经干细胞悬液、生理盐水5 μL。移植后5个月腹腔注射阿朴吗啡观察大鼠的行为学变化,取纹状体脑组织制备石蜡切片进行免疫组化荧光染色。结果与结论：治疗后第5个月骨髓基质干细胞组和中脑神经干细胞组大鼠旋转次数较治疗前显著下降(P < 0.05),且明显低于生理盐水组(P < 0.05),骨髓基质干细胞组和神经干细胞组比较差异无显著性意义(P > 0.05)。移植后第1周,骨髓基质干细胞组纹状体内有BrdU与Nestin双重染色细胞;移植后第1个月,脑纹状体内出现BrdU/GFAP双重染色细胞和BrdU/NSE双重染色细胞;纹状体内存在TH阳性细胞,但未出现明显BrdU/TH双重染色细胞;移植1个月之后,BrdU与Nestin双重染色细胞数量逐渐减少,最终基本消失,但仍然存在一定的数量的BrdU/GFAP、BrdU/NSE双重染色细胞,BrdU/GFAP阳性细胞数量相对较多。同一时间点,中脑神经干细胞组也存在类似情况,但生理盐水组未发现双标细胞。结果表明,中脑神经干细胞和骨髓基质干细胞移植均可改善帕金森大鼠的行为学,且可分化为神经元、星形胶质细胞、多巴胺能神经元。中国组织工程研究杂志出版内容重点：干细胞;骨髓干细胞;造血干细胞;脂肪干细胞;肿瘤干细胞;胚胎干细胞;脐带脐血干细胞;干细胞诱导;干细胞分化;组织工程     

大鼠胚胎神经干细胞黑质内移植后的存活及分化

目的：观察胚胎神经于细胞脑内移植后的存活及生长分化状况。方法：从孕11d(E11d)大鼠胚胎神经管获取神经上皮细胞，经神经巢蛋白(nestin)染色鉴定干细胞；同时植入同种大鼠黑质内。于移植后7d、14d取脑，用神经元特异烯醇化酶(NSE)、酪氨酸羟化酶(TH)免疫组化方法检测移植细胞的存活及分化状况。结果：E11d神经管上皮细胞多数呈nestin染色阳性，黑质内移植后增殖形成细胞团并随时间延长而增大。免疫组化染色显示移植细胞团内有NSE及TH免疫阳性细胞。结论：胚胎神经上皮细胞多数为神经干细胞，黑质内移植后可以存活并分化为多巴胺能神经元。     

移植间充质干细胞治疗帕金森病大鼠

目的移植骨髓间充质干细胞(MSCs)治疗大鼠帕金森病(PD)。方法将BrdU标记的MSCs移植到单侧注射6-OHDA制备的PD大鼠模型损毁侧纹状体内,由阿朴吗啡诱导大鼠的旋转行为,用免疫组化和免疫荧光法检测大鼠黑质TH的表达和移植细胞的存活、迁移和分化,用1H-MRS检测大鼠双侧纹状体N-乙酰门冬氨酸(NAA)、胆碱类化合物(Cho)、肌酸(Cr)的信号强度。结果骨髓MSCs定向移植术后8周,PD大鼠的旋转行为较术前明显改善,损毁侧黑质TH阳性细胞数较术前增加;BrdU阳性细胞散在分布于移植侧脑组织内,可表达神经胶质纤维酸性蛋白(GFAP)和微管相关蛋白2(MAP-2);PD大鼠损毁侧纹状体NAA/Cr较术前升高(P<0.05),Cho/Cr下降(P<0.05)。结论植入纹状体内骨髓MSCs能够存活并对PD模型大鼠有治疗作用。     

携带绿色荧光蛋白基因的神经上皮干细胞移植治疗帕金森病

背景：神经干细胞异体移植的细胞替代疗法是治疗帕金森病的热点,但先前的研究重点关注移植细胞的形态学信息和动物的行为改变,作用机制尚未明确。 目的：通过检测神经上皮干细胞脑内移植后帕金森病模型大鼠的旋转行为改变与其脑内多巴胺含量变化的关系,分析神经上皮干细胞移植治疗帕金森病的作用机制。 方法：建立帕金森病大鼠模型,造模后分为2组,实验组将携带绿色荧光蛋白基因的胚胎神经上皮干细胞克隆后移植到帕金森病模型大鼠的纹状体内,对照组注射等量的生理盐水。取材后检测移植细胞的存活与分化,对比分析大鼠行为改变与其脑内多巴胺含量变化的关系。 结果与结论：移植后实验组大鼠的旋转行为明显改善,移植细胞在宿主脑内存活良好,并分化出TH阳性细胞。实验组大鼠脑内多巴胺的含量明显高于对照组。提示携带绿色荧光蛋白基因的神经上皮干细胞脑内移植后帕金森病模型大鼠的旋转行为改善与其脑内多巴胺含量的变化成正比,分化出有功能的TH阳性细胞可能是神经干细胞移植治疗帕金森病的基本机制。 关键词：神经上皮干细胞;帕金森病;绿色荧光蛋白;转基因鼠;多巴胺 doi:10.3969/j.issn.1673-8225.2012.06.029     

神经干细胞在创伤性脑损伤灶周边的成活和迁移

背景:成年人中枢神经系统再生困难,颅脑损伤后,损伤灶周边区域神经细胞的存活数量直接影响患者的预后。如何有效地使移植入创伤性脑损伤灶周边的神经干细胞存活分化,是目前神经修复再生研究的重点。目的:探讨神经干细胞移植入大鼠创伤性脑损伤灶周边的成活、迁移和分化情况。方法:利用无血清培养技术,加入表皮生长因子、碱性成纤维生长因子诱导刺激大鼠胚胎源性前脑神经干细胞生长增殖,并在体外进行克隆培养,移植前行BrdU标记,采用免疫组化和免疫荧光法检测其增殖特性和多向分化潜能,并观察其移植到Fenney’s落体脑损伤模型鼠脑皮质内的成活和迁移情况。结果与结论:免疫组化及免疫荧光检测结果显示克隆细胞球呈nestin和BrdU阳性,分化后呈NSE,GFAP,MAP-2阳性。免疫组化及荧光双标检测结果显示移植后7,14d损伤灶周边散在BrdU阳性细胞,并且GFAP阳性细胞增多。提示前脑神经干细胞在体外培养中能够增殖,并分化为神经元和神经胶质细胞,移植后能够在创伤性脑损伤灶周边存活和迁移,形态上显示出与脑组织整合的特点。     

胚胎嗅鞘细胞和中脑腹侧细胞移植对帕金森病SD大鼠纹状体神经元存活和分化的影响

目的观察胚胎嗅球嗅鞘细胞(OECs)和胚胎中脑腹侧细胞(VMCs)联合移植对帕金森病(PD)SD大鼠纹状体神经元存活及分化的影响。方法 12只PD模型SD大鼠随机平均分成两组:单独VMCs组(在脑立体定位仪下将VMCs植入PD大鼠模型毁损侧纹状体内)和联合移植组(在脑立体定位仪下将OECs和VMCs植入PD大鼠模型毁损侧纹状体内)。OECs来源于5～7d绿荧光鼠的嗅球嗅鞘,VMCs来源于孕13～14d绿荧光胎鼠中脑腹侧的脑组织。于移植后4、14周灌注取脑,切片后做酪氨酸羟化酶(TH)免疫组织化学染色,检测胚胎中脑腹侧细胞的存活及分化状况。结果移植4周后单独VMCs组及联合移植组纹状体区都可检测到TH免疫阳性神经元,数量无统计学差异(P0.05)。移植14周后联合移植组纹状体区TH免疫阳性神经元数量比单独VMCs组明显增多(P0.05)。结论胚胎中脑腹侧细胞联合嗅鞘细胞移植入帕金森病大鼠纹状体促使纹状体神经元分化为多巴胺能神经元。     

神经干细胞移植对帕金森病样模型大鼠的治疗作用

目的 观察大鼠神经干细胞(NSC)植入帕金森病(PD)模型大鼠的脑纹状体后的存活、分化及功能状态.方法 体外分离培养NSC,单克隆培养,免疫细胞化学检测多向分化潜能和特异性标记nestin.建立PD大鼠模型,纹状体内植入DAPI标记的NSC,检测6-羟基多巴胺(6-HHDA)诱发的旋转行为,荧光检测标记细胞的分布情况,免疫细胞化学和高效液相色谱检测细胞分化和神经递质含量.结果 培养的NSC表达nestin,具有自我更新和多向分化能力;NSC植入PD模型大鼠纹状体后大鼠诱导旋转行为显著改善(P＜0.05);NSC在脑内迁移,并在纹状体内形成少量酪胺酸羟化酶(TH)阳性细胞、纤维;植入后纹状体内多巴胺(DA)及其代谢产物含量上升,2个月时分别增加3.6倍和2.8倍,4个月时增加3.4倍和2.4倍(P＜0.01).结论 神经干细胞在体外大量扩增后植入PD脑内能长期存活并分化、分泌神经递质,从而部分改善PD症状.     

Defining a developmental path to neural fate by global expression profiling of mouse embryonic stem cells and adult neural stem/progenitor cells

To understand global features of gene expression changes during in vitro neural differentiation, we carried out the microarray analysis of embryonic stem cells (ESCs), embryonal carcinoma cells, and adult neural stem/progenitor (NS) cells. Expression profiling of ESCs during differentiation in monolayer culture revealed three distinct phases: undifferentiated ESCs, primitive ectoderm-like cells, and neural progenitor cells. Principal component (PC) analysis revealed that these cells were aligned on PC1 over the course of 6 days. This PC1 represents approximately 4,000 genes, the expression of which increased with neural commitment/differentiation. Furthermore, NS cells derived from adult brain and their differentiated cells were positioned along this PC axis further away from undifferentiated ESCs than embryonic stem-derived neural progenitors. We suggest that this PC1 defines a path to neural fate, providing a scale for the degree of commitment/differentiation.     

Transplantable neural progenitor populations derived from rhesus monkey embryonic stem cells

Cell-based therapies using embryonic stem cells (ESCs) in the treatment of neural disease will require the generation of homogenous donor neural progenitor (NP) populations. Here we describe an efficient culture system containing hepatocyte growth factor (HGF) and G5 supplement for the production of highly enriched (88.3%+/-8.1%) populations of NPs from rhesus monkey ESCs. Additional purification resulted in NP preparations that were 98% nestin positive. Moreover, NPs, as monolayers or neurospheres, could be maintained for prolonged periods of time in media containing HGF+G5 or G5 alone. In vitro differentiation and in vivo transplantation assays showed that NPs could differentiate into neurons, astrocytes, and oligodendrocytes. The kinds and quantities of differentiated cells derived from NPs were closely correlated with their niches in vivo. Glial differentiation was predominant in periventricular areas, whereas cells migrating into the cortex were mostly neurons. Cell counts showed that 2 months after transplantation, approximately 25% of transplanted NPs survived and 65%-80% of the surviving transplanted cells migrated along the ventricular wall or in a radial fashion. Subcloning demonstrated that several clonal lines derived from NPs expressed nestin and differentiated into three neural lineages in vitro and in rat brains in vivo. In contrast, some subcloned lines showed restricted differentiation both in vitro and in vivo in rat brains. These observations set the stage for obtaining highly enriched NPs and evaluating the efficacy of NP-based transplantation therapy in the nonhuman primate and will provide a platform for probing the molecular mechanisms that control neural induction.     

Improved safety of hematopoietic transplantation with monkey embryonic stem cells in the allogeneic setting

Cynomolgus monkey embryonic stem cell (cyESC)-derived in vivo hematopoiesis was examined in an allogeneic transplantation model. cyESCs were induced to differentiate into the putative hematopoietic precursors in vitro, and the cells were transplanted into the fetal cynomolgus liver at approximately the end of the first trimester (n = 3). Although cyESC-derived hematopoietic colony-forming cells were detected in the newborns (4.1%-4.7%), a teratoma developed in all newborns. The risk of tumor formation was high in this allogeneic transplantation model, given that tumors were hardly observed in immunodeficient mice or fetal sheep that had been xeno-transplanted with the same cyESC derivatives. It turned out that the cyESC-derived donor cells included a residual undifferentiated fraction positive for stage-specific embryonic antigen (SSEA)-4 (38.2% +/- 10.3%) despite the rigorous differentiation culture. When an SSEA-4-negative fraction was transplanted (n = 6), the teratoma was no longer observed, whereas the cyESC-derived hematopoietic engraftment was unperturbed (2.3%-5.0%). SSEA-4 is therefore a clinically relevant pluripotency marker of primate embryonic stem cells (ESCs). Purging pluripotent cells with this surface marker would be a promising method of producing clinical progenitor cell preparations using human ESCs.     

Tenascin-R promotes neuronal differentiation of embryonic stem cells and recruitment of host-derived neural precursor cells after excitotoxic lesion of the mouse striatum

Loss of GABAergic projection neurons under excitotoxic conditions in the striatum is associated with a disturbance of motor and cognitive functions as seen, for instance, in Huntington's disease. Since current treatments cannot replace degenerated neurons, research on alternative therapeutic approaches needs to be pursued. In this context, the transplantation of genetically modified stem cells into lesioned brain areas of patients is a possible alternative. In this study, green fluorescent protein-labeled murine embryonic stem cells (ESCs) were stably transfected to overexpress the extracellular matrix molecule tenascin-R (TNR), which is expressed by striatal GABAergic neurons. TNR-overexpressing ESCs were analyzed in comparison with their parental cells regarding neural differentiation and migration in vitro, and after transplantation into the striatum of quinolinic acid-treated mice, which serve as a model for Huntington's disease. In comparison with sham-transfected control cells, TNR-overexpressing ESCs showed enhanced differentiation into neurons in vitro, reduced migration in vitro and in vivo, and increased generation of GABAergic neurons and decreased numbers of astrocytes 1 month and 2 months after transplantation, but without significant effects on locomotor functions. Interestingly, TNR-overexpressing ESCs transplanted into the striatum attracted host-derived neuroblasts from the rostral migratory stream and promoted stem cell-mediated recruitment of host-derived newborn neurons within the grafted area. Thus, we show for the first time that overexpression of an extracellular matrix molecule by in vitro predifferentiated ESCs exerts beneficial effects on tissue regeneration in a mouse model of neurodegenerative disease. Disclosure of potential conflicts of interest is found at the end of this article.     

Transplantation of Cultured Human Neural Progenitor Cells into Rat Brain: Migration and Differentiation

We studied the fate in vitro cultured human stem/progenitor cells after transplantation into rat brain. The cells from human fetuses at 8-12 weeks' gestation were cultured in vitro for 14 days and transplanted into the brain of 10-day-old and adult rats. Microscopic examination showed that human stem/progenitor cells migrated into various regions of rat brain. Immunohistochemical assay demonstrated that some cells differentiated into astrocytes and neurons, while others retained the embryonic phenotype.     

Neural stem cells directly differentiated from partially reprogrammed fibroblasts rapidly acquire gliogenic competency

Neural stem cells (NSCs) were directly induced from mouse fibroblasts using four reprogramming factors (Oct4, Sox2, Klf4, and cMyc) without the clonal isolation of induced pluripotent stem cells (iPSCs). These NSCs gave rise to both neurons and glial cells even at early passages, while early NSCs derived from clonal embryonic stem cells (ESCs)/iPSCs differentiated mainly into neurons. Epidermal growth factor-dependent neurosphere cultivation efficiently propagated these gliogenic NSCs and eliminated residual pluripotent cells that could form teratomas in vivo. We concluded that these directly induced NSCs were derived from partially reprogrammed cells, because dissociated ESCs/iPSCs did not form neurospheres in this culture condition. These NSCs differentiated into both neurons and glial cells in vivo after being transplanted intracranially into mouse striatum. NSCs could also be directly induced from adult human fibroblasts. The direct differentiation of partially reprogrammed cells may be useful for rapidly preparing NSCs with a strongly reduced propensity for tumorigenesis.     

Human embryonic stem cell-derived neural precursor transplants attenuate apomorphine-induced rotational behavior in rats with unilateral quinolinic acid lesions

To test the efficacy of human embryonic stem cell (hESC)-derived neural precursors in an experimental model of Huntington's disease (HD), we differentiated hESC into nestin-positive neural precursors by co-culturing with PA6 stromal cells, and subsequently transplanted them into the striatum of quinolinic acid (QA)-induced HD model. The transplanted animals exhibited a behavioral recovery in the apomorphine-induced rotation test for 3 weeks after transplantation. The transplanted hESC-derived neural precursors were found in both cortex and striatum. They also exhibited some evidence of neuronal differentiation. At the time of examination, no tumor was detected. These results strongly suggest that hESC-derived neural precursors can lead to a behavioral recovery, as well as neuronal differentiation, in the pre-clinical model of HD.     

神经前体细胞的增殖和分化及其对Parkinson病的治疗作用

本实验分离 1 1～ 1 5 d胎鼠的大脑皮层 ( CP)和中脑的神经前体细胞 ( MP) ,观察它们在体外的增殖和分化及其对帕金森病 ( PD)的治疗作用。结果发现 ,CP较 MP生长迅速 ,容易形成神经球 ,加入 N2 / B2 7有助于神经球的形成 ;有 /无血清分化后 ,CP和 MP都能发育成微管相关蛋白 -2 ( MAP-2 )阳性细胞 ,其中 MP倾向于发育成酪氨酸羟化酶 ( TH)阳性细胞。将 MP或 CP植入6 -OHDA损伤的大鼠纹状体后 ,MP发育成的 TH+神经元数量明显地较 CP移植组和对照组者多 ( P<0 .0 5 )且 MP移植后 4～ 8周旋转行为发生明显改善 ,与 CP移植组和对照组相比有显著性差异 ( P<0 .0 5 )。上述结果提示 ,虽然 CP在体外的增殖能力较MP强 ,但 MP更易于分化成 TH阳性神经元并改善 PD大鼠的旋转行为 ,此点对于神经前体细胞治疗 PD的应用极其重要。