骨髓间充质干细胞分化为神经元样细胞后电生理特性的改变

背景：目前体外实验对骨髓间充质干细胞来源的神经元样细胞的研究多集中于形态学层面和神经标志物方面,对分化后的电生理功能研究较少。 目的：观察脑源性神经营养因子/碱性成纤维细胞生长因子/全反式维甲酸诱导Wistar大鼠骨髓间充质干细胞分化为神经元样细胞后电生理特性的变化。 设计、时间及地点：细胞学体外培养,对比观察,于2005-06/2007-10在天津市环湖医院细胞室和南开大学生命科学院完成。 材料：6周龄雄性Wistar大鼠3只,体质量160 g左右。 方法：贴壁培养法体外分离纯化间充质干细胞,用脑源性神经营养因子/碱性成纤维细胞生长因子/全反式维甲酸联合诱导间充质干细胞向神经元样细胞分化。诱导前和诱导3 d后分别用膜片钳技术检测细胞膜电流。 主要观察指标：流式细胞仪检测间充质干细胞表型;倒置显微镜观察诱导分化前后细胞形态变化;免疫细胞化学鉴定神经元特异性烯醇化酶的表达,以及全细胞电流测定结果。 结果：①流式细胞仪检测结果显示,CD90阳性率(99±3)%,CD31阳性率(3.4±0.8)%,CD34阳性率(0.3±0.1)%。说明这一细胞群大部分处于未分化的干细胞状态,其纯度可达95%。②光镜下可见未经诱导的间充质干细胞多为扁平形带突起的细胞,似纤维样细胞,诱导3 d后出现神经元样细胞。③免疫细胞化学结果显示,诱导前间充质干细胞的神经元特异性烯醇化酶呈弱阳性,诱导后呈强阳性。诱导72 h时分化率为(24.01±3.76)%。④诱导组神经元样细胞外向电流峰值及最大外向电流密度高于对照组(P < 0.05),但未发现内向钠电流。 结论：脑源性神经营养因子/碱性成纤维细胞生长因子/全反式维甲酸诱导方法可以诱导间充质干细胞向神经元方向分化,虽未发现具有成熟神经元电生理功能,但有向成熟神经元分化的趋势。     

低氧联合GDNF诱导大鼠神经干细胞分化为TH阳性神经元的实验研究

目的本试验在低氧环境下利用胶质源性神经营养因子(GDNF)对大鼠胚胎神经干细胞(NSCs)进行定向诱导分化,从而研究低氧对NSCs向多巴胺能神经元分化的影响,并获得相当数量的多巴胺能细胞,为下一步的细胞移植奠定基础。方法分离培养孕14 d～16 d Wistar大鼠胚胎皮质NSCs,通过传代培养获得单克隆生长的NSCs,在不同氧浓度下利用GDNF对大鼠NSCs进行定向诱导分化,通过免疫细胞化学方法检测TH阳性细胞表达。结果低氧可明显促进NSCs向TH阳性神经元分化,与常氧对照组比较有显著差异(P 0.01),且在3%低氧浓度时,NSCs向TH阳性神经元分化率最高。结论低氧可促进NSCs向TH阳性神经元分化,3%低氧浓度是促进NSCs向TH阳性神经元分化的最适氧浓度,低氧促进NSCs向TH阳性神经元分化的分化率与氧浓度梯度无依赖关系,低氧联合GDNF诱导NSCs分化为TH阳性神经元,诱导效能更为显著。     

胶质源性神经营养因子与白细胞介素1β体外诱导中脑神经干细胞的分化

背景：在神经干细胞移植治疗帕金森病中,移植细胞的数量及多巴胺能神经元的分化比率是必须解决的问题,而有效的神经干细胞体外增殖与多巴胺能神经元的大量定向诱导分化是解决问题的关键所在。 目的: 探讨胶质源性神经营养因子与白细胞介素1β体外诱导中脑神经干细胞向多巴胺能神经元的分化。 方法:分离妊娠12 d小鼠胚胎腹侧中脑,经胰酶消化和机械吹打制成单细胞悬液,离心过滤后机械方法传代培养5~7 d的神经球,分组进行诱导分化10~12 d,待80%细胞从神经球迁移出来,分化为单细胞时,进行免疫细胞化学鉴定及流式细胞术检测酪氨酸羟化酶阳性细胞率。 结果与结论：神经球细胞表达巢蛋白抗原,能分化为神经元特异性烯醇化酶和胶原纤维酸性蛋白阳性细胞。胶质源性神经营养因子与白细胞介素1β在体外能明显提高中脑神经干细胞分化为酪氨酸羟化酶阳性神经元的比例,胶质源性神经营养因子诱导组、白细胞介素1β诱导组和两者联合应用均较空白对照组比例高,尤其是两者联合应用作用更显著,说明胶质源性神经营养因子、白细胞介素1β可明显促进中脑神经干细胞分化为数量足够、形态及功能成熟的多巴胺能神经元。     

底蜕膜间充质干细胞分化为多巴胺能样神经元

目的 探讨人胎盘底蜕膜间充质干细胞体外向多巴胺能样神经元分化的潜能,并优化诱导方案.方法 体外分离培养底蜕膜间充质干细胞,用表皮生长因子(EGF)+人碱性成纤维细胞生长因子(bFGF)+ B27添加剂和人音猬因子(SHH)+成纤维细胞生长因子8(FGF8)+forskolin+脑源性神经营养因子(BDNF)分两个阶段对其进行诱导;免疫细胞化学先后检测干细胞标记nestin和CD133、成熟神经元标记神经元特异性烯醇化酶(NSE)、神经胶质细胞标记胶质原纤维酸性蛋白(GFAP)、多巴胺能神经元标记酪氨酸羟化酶(TH)的表达;Western blot验证诱导后TH蛋白的表达;高效液相色谱-电化学检测诱导前后多巴胺的分泌.结果 经第一阶段诱导后,细胞形成漂浮生长的神经球,nestin和CD133均呈阳性表达;第二阶段诱导后,出现明显的神经元样形态,NSE、GFAP和TH均阳性表达,Western blot也显示TH蛋白的表达,多巴胺分泌量相比诱导前明显增加(P＜0.001).结论 底蜕膜间充质干细胞体外可分化为多巴胺能样神经元,可能成为帕金森病干细胞移植治疗新的种子细胞来源.     

音速波状蛋白促进骨髓间充质干细胞向多巴胺能神经元分化

目的探讨音速波状蛋白（Shh）促进人骨髓间充质干细胞（MSCs）体外定向分化为多巴胺能神经元样细胞的作用。方法体外分离、扩增和鉴定人骨髓MSCs。采用不同诱导方案诱导MSCs向神经元和多巴胺能神经元样细胞定向转化后,进行抗神经巢蛋白（Nestin）、神经元特异烯醇化酶（NSE）、神经胶质纤维酸性蛋白（GFAP）、酪氨酸羟化酶（TH）和多巴胺转运体（DAT）等免疫细胞化学染色,并计算阳性细胞百分率。结果实验组诱导后MSCs能分化为具有典型神经元形态的细胞,可见NSE、Nestin、GFAP、TH和DAT等神经细胞标志表达;对照组MSCs细胞形态无明显变化,上述特异性标志物表达均为阴性。实验2组（诱导方案含Shh）与1组（诱导方案不含Shh）的NSE、Nestin、GFAP阳性细胞百分率的差异无统计学意义,但实验2组TH和DAT阳性细胞百分率明显高于实验1组,差异具有统计学意义（P〈0.05）。结论Shh可促进MSCs分化为多巴胺能神经元样细胞。     

预诱导与全反式维甲酸并脑源性神经营养因子体外诱导骨髓基质干细胞向神经元样细胞的分化

背景：骨髓基质干细胞可定向诱导分化为神经元样细胞,但目前培养的方法尚不统一。 目的：采用预诱导与全反式维甲酸和脑源性神经营养因子为培养体系,拟在体外诱导大鼠骨髓基质干细胞向神经细胞分化。 设计、时间及地点：细胞学体外观察,于2007-12/2008-06在新疆医科大学第一附属医院医学研究中心干细胞室完成。 材料：清洁级雄性SD大鼠2只,由新疆医科大学动物试验中心提供。 方法：采用贴壁法体外分离培养大鼠骨髓基质干细胞,经反复传代细胞逐渐纯化。取生长状态良好的第3代骨髓基质干细胞,按8×107 L-1密度接种后,改换含10 μg/L碱性成纤维细胞生长因子、20 μg/L表皮生长因子的神经干细胞培养体系进行预诱导,48 h后去除预诱导液,加入含10 μg/L脑源性神经生长因子、1 μmol/L全反式维甲酸的神经干细胞培养体系定向诱导骨髓基质干细胞分化为神经细胞。以未诱导的骨髓基质干细胞作为对照。 主要观察指标：流式细胞仪检测第3代骨髓基质干细胞表面标志的表达,诱导后免疫荧光染色和流式细胞仪检测巢蛋白阳性的表达,免疫荧光染色鉴定神经元特异性烯醇化酶和胶质纤维酸性蛋白的表达。 结果：第3代骨髓基质干细胞CD29,CD44表达率分别为97.1%,99%,CD45表达率为0.5%,CD34呈阴性表达。预诱导48 h后巢蛋白阳性率为24%,而对照组仅为4.6%。诱导48 h后,巢蛋白染色呈阳性,并可见大量神经元特异性烯醇化酶和胶质纤维酸性蛋白阳性细胞出现;对照组均呈阴性表达。 结论：神经干细胞培养体系联合全反式维甲酸与脑源性神经生长因子,可在体外高效、稳定地诱导骨髓基质干细胞转化为神经元样细胞,并进一步向神经元和神经胶质细胞方向分化。     

Mes42细胞及细胞因子对中脑和纹状体神经前体细胞的分化作用

了解中脑神经前体细胞和纹状体神经前体细胞在Mes42细胞及细胞因子作用下的体外诱导分化情况.采用含细胞因子或/和Mes42细胞条件培养基和细胞膜碎片的分化培养基培养中脑神经前体细胞和纹状体神经前体细胞,孵育7 d后行免疫细胞化学染色了解其体外诱导分化情况.IL-lα(100pg/ml),IL-11(1 ng/ml),GDNF(1μg/ml)和LIF(1 ng/ml)可诱导中脑神经前体细胞分化成TH阳性神经元,增加分化的TH阳性细胞数目.Mes42细胞条件培养基和其细胞膜裂解碎片以及细胞因子IL-11,LIF,GDNF,IL-1α共同培养神经前体细胞,诱导分化的TH阳性细胞数目无明显增加,但TH阳性细胞的形态更趋成熟.而纹状体神经前体细胞在上述分化培养基内鲜见TH阳性细胞.中脑神经前体细胞可在体外被诱导分化成TH阳性神经元,可能成为帕金森病移植治疗的供体细胞.     

多因子联合诱导脂肪组织源性干细胞分化为神经元样细胞

背景：国内均可见有探讨脂肪干细胞向神经元诱导分化的相关研究报道,但运用差速贴壁法纯化脂肪组织源性干细胞,多因子联合诱导脂肪组织源性干细胞分化为神经元样细胞的研究鲜有报道。 目的：观察多因子联合诱导和分步诱导方案诱导大鼠脂肪组织源性干细胞体外分化为神经元样细胞的可行性。 方法：取SD雄性大鼠腹股沟和附睾脂肪垫脂肪组织,酶消化法分离、差速贴壁法纯化脂肪组织源性干细胞。免疫荧光细胞化学法鉴定脂肪组织源性干细胞(CD44,CD49d,CD106);“鸡尾酒”式神经元诱导培养基对脂肪组织源性干细胞进行诱导分化,并用免疫荧光细胞化学法鉴定(Nestin和NeuN)分化结果。 结果与结论：大鼠腹股沟和附睾脂肪垫脂肪组织内分离、原代培养的脂肪组织源性干细胞形态均一,呈长梭形,细胞核椭圆形,核仁明显,细胞质染色浅,呈旋涡状克隆样生长;CD44和CD49d阳性表达而CD106阴性;诱导培养基内培养6 h后脂肪组织源性干细胞呈锥体形或不规则,有短而细的指状突起;24 h后多数细胞显示类神经元的形态学特征,且Nestin和NeuN阳性。提示肪组织源性干细胞在多因子“鸡尾酒”式培养基内可向神经元方向分化。     

成人骨髓间充质干细胞的体外培养和定向神经分化

目的 探讨成人骨髓间充质干细胞(MSCs)的体外培养和定向神经诱导分化的条件.方法 从正常成人志愿者髂骨中分离获取MSCs,体外培养扩增纯化后传代于塑料培养皿中,以含有脑源性生长因子(BDNF)联合维A酸(RA)的培养液对传至3～5代的细胞进行体外诱导分化,采用免疫细胞化学法对诱导后的细胞鉴定.结果 诱导1h有部分细胞表达神经干细胞标志巢蛋白nestin,6h后大部分细胞具有典型神经元形态.表达神经元特异性烯醇化酶(NSE)阳性细胞占细胞总数的(46.45±2.54)%.结论 MSCs可通过体外培养并纯化,应用BDNF联合RA可以在体外诱导MSCs成为神经元样细胞.     

人皮肤源性间充质干细胞体外诱导向淋巴细胞分化的可能性

背景：研究发现真皮组织中存在间充质干细胞,存在自体移植的可能性。如能在一定条件下将皮肤来源的间充质干细胞诱导分化为淋巴细胞,则可解决许多免疫系统损伤疾病。 目的：探讨人皮肤源性间充质干细胞经体外诱导向淋巴细胞转分化的可能性。 方法：体外培养人皮肤源性间充质干细胞至第14代,流式细胞仪检测细胞表面标志的表达。诱导人皮肤源性间充质干细胞转分化的条件培养基由人淋巴细胞培养上清液和新鲜人皮肤源性间充质干细胞培养液以7∶3比例组成。倒置显微镜观察诱导后细胞形态学变化。流式细胞仪检测诱导后1~8 d细胞表面淋巴细胞标志的表达。流式细胞仪检测诱导后3,6,9 d人皮肤间充质干细胞自身标记表达的变化。 结果与结论：人皮肤源性间充质干细胞稳定表达自身特异性标志CD73,Vimentin等,不表达造血系统特异性标志CD34,CD45等,且低表达HLA-I,完全不表达HLA-DR。诱导3 d后,细胞体积明显增大,细胞增殖速度明显低于诱导前,细胞内和细胞间存在许多折光性强的囊胞样颗粒。除CD45淋巴细胞标志的表达无明显变化外,诱导后1~ 4 d人皮肤源性间充质干细胞CD3,CD19,CD16,CD4,CD8的表达率均随诱导时间的延长呈线性升高趋势,诱导后5~8 d处于平台期。诱导后3,6,9 d人皮肤源性间充质干细胞自身标记CD73,CD34,Vimentin,HLA-DR的表达无变化,HLA-I的表达率随诱导时间的延长逐渐上升。提示在体外人皮肤源性间充质干细胞可以被诱导向淋巴细胞转分化,具有参与免疫系统损伤修复的潜能。     

Tyrosine hydroxylase-positive cells and dopaminergic neuronal function in human embryonic stem cells An electrophysiological validation

BACKGROUND: Induced differentiation strategies and cytochemical properties of human embryonic stem cells (hESCs) have been investigated. However, the electrophysiological functions of tyrosine hydroxylase (TH)-positive cells derived from hESCs remain unclear. OBJECTIVE: To investigate the differentiation efficiency of TH-positive cells from hESCs in vitro using modified four-step culture methods, including embryoid body formation, and to examine the functional characteristics of the differentiated TH-positive cells using electrophysiological techniques.DESIGN, TIME AND SETTING: Neuroelectrophysiology was performed at the Reproductive Medicine Center and Stem Cell Research Center, Peking University Third Hospital, and the Neuroscience Research Institute and Department of Neurobiology, Peking University, from September 2004 to August 2008.MATERIALS: The hESC line, PKU-1.1, a monoclonal cell line derived from a pre-implantation human blastocyst in the Reproductive Medical Center of Peking University Third Hospital. The patch clamp recording system was provided by the Neuroscience Research Institute and Department of Neurobiology, Peking University. METHODS: The hESC line was induced to differentiate into TH-positive cells in vitro using a modified four-step culture method, including the formation of embryoid body, as well as the presence of sonic hedgehog and fibroblast growth factor 8. The cell karyotype was assessed by G-banding karyotype analysis techniques and specific markers were detected immunocytochemically. Whole-cell configuration was obtained after obtaining a tight seal of over 1 GΩ. Ionic currents were detected by holding the cells at -70 mV and stepping to test voltages between 80 and 40 mV in 10-mV increments in voltage-clamp configuration. MAIN OUTCOME MEASURES: We measured the cell karyotype, specific cell markers, and the electrophysiological properties of the voltage-gated ion channels on the cell membrane of TH-positive dopaminergic cells differentiated from our hESCs line in vitro. RESULTS: The differentiated cells had a consistent appearance, and the majority of cells (> 90%) expressed TH and (3-tubulion, as well as the neural progenitor marker, nestin. Cell karyotype analysis demonstrated that all of the hESCs had a stable and normal karyotype (46, XX) after differentiation. In addition, patch clamp recording showed that the 10 recorded TH-positive cells exhibited a fast inward current when the test voltage depolarized to 30 mV, and a delayed outward current when the test voltage depolarized to -10 mV. The peak of inward current was obtained at voltage between -10 mV and 0 mV, while the peak of outward current was obtained at 40 mV. The average peak of inward current density was (-50.05 ± 15.50) pA/pF, and the average peak of outward current density was (41.98 ± 13.55) pA/pF.CONCLUSION: More than 90% of the differentiated hESC-derived cells induced by the modified four-step culture method exhibit dopaminergic neuronal properties, including general electrophysiological functional properties, such as functional potassium and sodium channels.     

Stromal factors SDF1α, sFRP1, and VEGFD induce dopaminergic neuron differentiation of human pluripotent stem cells

Human embryonic stem cell (hESC)-derived dopaminergic (DA) neurons hold potential for treating Parkinson's disease (PD) through cell replacement therapy. Generation of DA neurons from hESCs has been achieved by coculture with the stromal cell line PA6, a source of stromal cell-derived inducing activity (SDIA). However, the factors produced by stromal cells that result in SDIA are largely undefined. We previously reported that medium conditioned by PA6 cells can generate functional DA neurons from NTera2 human embryonal carcinoma stem cells. Here we show that PA6-conditioned medium can induce DA neuronal differentiation in both NTera2 cells and the hESC I6 cell line. To identify the factor(s) responsible for SDIA, we used large-scale microarray analysis of gene expression combined with mass spectrometric analysis of PA6-conditioned medium (CM). The candidate factors, hepatocyte growth factor (HGF), stromal cell-derived factor-1 α (SDF1α), secreted frizzled-related protein 1 (sFRP1), and vascular endothelial growth factor D (VEGFD) were identified, and their concentrations in PA6 CM were established by immunoaffinity capillary electrophoresis. Upon addition of SDF1α, sFRP1, and VEGFD to the culture medium, we observed an increase in the number of cells expressing tyrosine hydroxylase (a marker for DA neurons) and βIII-tubulin (a marker for immature neurons) in both the NTera2 and I6 cell lines. These results indicate that SDF1α, sFRP1, and VEGFD are major components of SDIA and suggest the potential use of these defined factors to elicit DA differentiation of pluripotent human stem cells for therapeutic intervention in PD.     

A simple method for large-scale generation of dopamine neurons from human embryonic stem cells

Dopamine (DA) neurons derived from human embryonic stem cells (hESCs) are potentially valuable in drug screening and as a possible source of donor tissue for transplantation in Parkinson's disease. However, existing culture protocols that promote the differentiation of DA neurons from hESCs are complex, involving multiple steps and having unreliable results between cultures. Here we report a simple and highly reproducible culture protocol that induces expandable DA neuron progenitors from hESCs in attached cultures. We found that the hESC-derived neuronal progenitors retain their full capacity to generate DA neurons after repeated passaging in the presence of basic fibroblast growth factor (bFGF) and medium conditioned with PA6 stromal cells. Using immunocytochemistry and RT-PCR, we found that the differentiated DA neurons exhibit a midbrain phenotype and express, e.g., Aldh1a, Ptx3, Nurr1, and Lmx1a. Using HPLC, we monitored their production of DA. We then demonstrated that the expanded progenitors are possible to cryopreserve without loosing the dopaminergic phenotype. With our protocol, we obtained large and homogeneous populations of dopaminergic progenitors and neurons. We conclude that our protocol can be used to generate human DA neurons suitable for the study of disease mechanisms, toxicology, drug screening, and intracerebral transplantation.     

Generation of dopamine neurons from embryonic stem cells in the presence of the neuralizing activity of bone marrow stromal cells derived from adult mice

Stromal cell lines such as PA6 and MS5 have been employed for generating dopamine (DA) neurons from embryonic stem (ES) cells. The present study was designed to test whether bone marrow stromal cells (BMSC) derived from adult mice might be available as a feeder layer to produce DA cells efficiently from ES cells. When ES cells were grown on BMSC in the presence of fibroblast growth factor 8 (FGF8) and sonic hedgehog (SHH), about 40% of TuJ1-positive neurons expressed tyrosine hydroxylase (TH). Because these cells labeled with TH were negative for dopamine-beta-hydroxylasae (DBH), the marker for noradrenergic and adrenergic neurons, the TH-positive cells were most likely DA neurons. They indeed expressed midbrain DA neuron markers such as Nurr 1, Ptx-3, and c-ret and were capable of synthesizing and releasing DA in vitro. Furthermore, DA neurons differentiated from ES cells in this differentiation protocol survived transplantation in rats with 6-hydroxydopamine lesions and reversed the lesion-induced circling behavior. The data indicate that BMSC can facilitate an efficient induction of DA neurons from ES cells and that the generated DA neurons are biologically functional both in vitro and in vivo. Insofar as BMSC have recently been employed in autologous cell therapy for ischemic heart and arteriosclerotic limb diseases, the present study raises the possibility that autologous BMSC can be applied in future cell transplantation therapy in Parkinson's disease.     

Estrogen promotes differentiation and survival of dopaminergic neurons derived from human neural stem cells

To investigate the effect of estrogen on neuronal differentiation, especially on dopaminergic (DA) neurons, human neural stem cells (NSCs) were differentiated in the presence of 17beta-estradiol. NSCs gave rise to tyrosine hydroxylase (TH)-positive neurons in vitro, the proportion of which was increased by 17beta-estradiol. Increase in TH-positive neurons was abrogated by an estrogen receptor (ER) antagonist, ICI182780, suggesting ERs play a role in differentiation of DA neurons. The observation that ERs were expressed in both proliferating NSCs and postmitotic DA neurons suggested that increase in TH-positive neurons was due to induction and support of DA neurons. 17beta-Estradiol also increased the number of DA neurons derived from human NSCs in vivo when the cells were grafted into mouse brains. These results support a possible role for estrogen in the transplantation of NSCs for Parkinson's disease.     

Efficient production of neural stem cells and neurons from embryonic stem cells

We have developed a simple method to efficiently produce a large number of neural stem cells and neurons from mouse embryonic stem (ES) cells. When cultured in astrocyte-conditioned medium (ACM) with mitogens (FGF-2 and EGF) under free-floating conditions, colonies of undifferentiated ES cells give rise to neural stem spheres (NSSs), composed of plentiful neural stem cells. Subsequent culture of the NSSs on an adhesive substrate with mitogens results in the migration of neural stem cells onto the substrate. These cells can be expanded, preserved by freezing, and differentiated into functional neurons. Neural stem cells and neurons provided by this NSS method may be valuable as potential donor cells for neuronal transplantation and also as convenient alternatives to tissue-derived neural cells.     

神经干细胞转染酪氨酸羟化酶基因后的分化

目的 探讨神经干细胞（NSCs）转梁酪氨酸羟化酶（TH）基因后的分化。方法 从胚胎16天Wistar大鼠室管膜前下周围区分离、增殖、鉴定NSCs；将TH基因和缺陷性逆转录病毒载体N2A构建成真核表达质粒，以电穿孔将其转入PA317包装细胞内；收集PA317包装产生的逆转录病毒颗粒，感染体外培养的NSCs，经G418筛选，获得成功转染TH基因的NSCs克隆；分别以0.4ng/ml bFGF和5％胎牛血清诱导转染及未转染TH基因的NSCs分化，比较TH基因转染及不同诱导方式对NSCs分化的影响，同时在分化细胞内检测TH的表达。结果 以0.4ng/ml bFGF诱导可使95％以上的NSCs分化为神经元，而5％FBS诱导则大多分化为神经胶质细胞，无论是否转染TH基因，神经元及神经胶质细胞的分化比例不成生改变；TH基因转染后能在神经干细胞的子代细胞内高效、稳定表达。结论 TH基因转染不影响NSCs的分化潜能，TH能在神经干细胞的子代细胞中有效表达0.4ng/ml bFGF诱导可以促使NSCs分化为神经元。     

Loss of RE-1 silencing factor in mesenchymal stem cell-derived dopamine progenitors induces functional maturity

Stem cell-derived dopamine (DA) neurons hold great promise for Parkinson's disease (PD). Mesenchymal stem cells (MSCs) have great potential for clinical applications. The generation of DA cells from MSCs using sonic hedgehog (SHH) and fibroblast growth factors (FGF8 and bFGF) has been reported. However, the DA cells showed weak electrical properties, representing DA neuron progenitors. Since RE-1 Silencing Factor (REST), suppresses mature neuronal genes in neuronal progenitors, we studied its role in the maturation of MSC-derived DA cells. REST expression did not change during the induction process, thus we knocked down REST and subjected MSCs to the same neural induction cocktail. We observed increases in the protein level of the Na(+) voltage-gated channel and tyrosine hydroxylase (TH). Electrophysiological analyses showed spontaneous firings and spontaneous postsynaptic currents, similar to native DA neurons. Taken together, these results show REST as the limiting gene in the generation of functional mature neurons from MSCs.     

胚胎大鼠神经干细胞电生理特性检测

目的 探讨胚胎大鼠神经干细胞体外培养分化的子代细胞电生理特性。方法 传代细胞单层贴壁培养,细胞内电流钳记录静息膜电位、动作电位、膜阻抗等电生理指标。结果 神经干细胞在现有培养条件下可初步分化为神经元和胶质细胞,并表现出不同的电生理特性。结论 神经干细胞表现出多向分化潜能,但现有培养条件尚不能使子代细胞电生理功能完全成熟。