Culturing of Specialized Glial Cells (Olfactory Ensheathing Cells) of Human Olfactory Epithelium

A monolayer of dissociated glial cells of human olfactory epithelium was cultured in Petri dishes and 12-well plates using a polylysine-laminin substrate. Primary cultures were sub-cultured after 10–15 days. The cell cultures were analyzed by phase contrast microscopy at all stages of culturing. A cytological study involved histological methods (trypan blue staining) and immunocytochemical visualization of GFAP, nestin, and low-affinity nerve growth factor receptors. At the final stage of culturing (5 passages) the monolayer cultures included 2 types of cells: GFAP- and p75-positive glial cells and nestin-positive fibroblasts.__________Translated from Kletochnye Tekhnologii v Biologii i Meditsine, No. 2, pp. 95–98, 2005     

内皮细胞对神经干细胞增殖与分化的影响

已经确定神经干细胞在脑中不是随意分布,而是集中在血管周围的。尽管神经干细胞存在于血管周围,但是对于其与血管组成细胞之间的关系还不是很清楚。据报道,内皮细胞释放的可溶性因子可以刺激神经干细胞自我增殖,抑制其分化,并且提高神经元的比例。将内皮细胞与神经干细胞共同培养可以激活Notch途径来促进神经干细胞自我增殖。另外,血管内皮生长因子对神经细胞的生长也起着非常重要的作用,它促进了中枢神经系统星形胶质细胞的生长与分化。因此,内皮细胞不仅是传统意义上血管的组成部分,还是神经干细胞所在区域的重要成分,并且可以通过大脑产生的神经营养性分泌物来提高神经元的发生。     

Standardized Generation and Differentiation of Neural Precursor Cells from Human Pluripotent Stem Cells

Precise, robust and scalable directed differentiation of pluripotent stem cells is an important goal with respect to disease modeling or future therapies. Using the AggreWell?400 system we have standardized the differentiation of human embryonic and induced pluripotent stem cells to a neuronal fate using defined conditions. This allows reproducibility in replicate experiments and facilitates the direct comparison of cell lines. Since the starting point for EB formation is a single cell suspension, this protocol is suitable for standard and novel methods of pluripotent stem cell culture. Moreover, an intermediate population of neural precursor cells, which are routinely >95% NCAM^pos and Tra-1-60^neg by FACS analysis, may be expanded and frozen prior to differentiation allowing a convenient starting point for downstream experiments.     

神经干细胞向运动神经元分化及移植的研究进展

神经干细胞是神经科学领域研究的热点之一.在体外适当的条件下神经干细胞可诱导分化成运动神经元,如添加生长因子、相关信号分子、或添加从脊髓源性神经胶质细胞提取的特殊培养液和骨骼肌培养液等,定向诱导分化的神经元移植于脑或脊髓的病变部位将成为运动神经元退行性病变的潜在治疗方法.     

嗅鞘细胞的培养纯化及形态学特征

目的　建立体外培养纯化嗅鞘细胞 (Olfactoryensheathingcells,OECs)的模型 ,观察OECs生长状态和形态学变化 ,为研究神经再生获得丰富OECs来源奠定基础。方法　以原代培养的方法分离、培养成年大鼠嗅球OECs,再用阿糖胞苷抑制 ,P75抗体吸附方法纯化及Forskolin和牛垂体提取液 (bovinepituitaryextract,BPE)营养物质综合作用。根据P75免疫组化学染色结果统计所得OECs的纯度 ,同时对不同培养时期的OECs的形态进行观察。结果　 (1)此纯化方法所得的OECs纯度可达 95 %以上 ,细胞增殖速度较快 ,且细胞纯度不因培养时间的延长而明显下降。 (2 )未纯化前细胞形态多变 ,主要为巨噬细胞状、双极和多极状 ;纯化后 2～ 4天 ,OECs多呈双极或多极状 ;突起短小 ;4天后 ,OECs以突起细长的双极和三极为主 ,细胞走向一致 ,呈平行排列。结论　P75抗体吸附方法纯化效率高 ,Forskolin和BPE能够促进细胞的增殖 ,并影响细胞的形态及排布     

Lessons from the Embryonic Neural Stem Cell Niche for Neural Lineage Differentiation of Pluripotent Stem Cells

Pluripotent stem cells offer an abundant and malleable source for the generation of differentiated cells for transplantation as well as for in vitro screens. Patterning and differentiation protocols have been developed to generate neural progeny from human embryonic or induced pluripotent stem cells. However, continued refinement is required to enhance efficiency and to prevent the generation of unwanted cell types. We summarize and interpret insights gained from studies of embryonic neuroepithelium. A multitude of factors including soluble molecules, interactions with the extracellular matrix and neighboring cells cooperate to control neural stem cell self-renewal versus differentiation. Applying these findings and concepts to human stem cell systems in vitro may yield more appropriately patterned cell types for biomedical applications.     

大鼠骨髓间充质干细胞向神经细胞和星形胶质细胞分化的研究

目的探讨体外诱导骨髓间充质干细胞(BMSCs)分化成神经细胞或星形胶质细胞。方法使用四种不同的诱导方式来处理BMSCs:-巯基乙醇(BME)、维甲酸(RA)、无血清培养基以及和新生鼠的脑星形胶质细胞共培养。结果四种方法处理后,BMSCs都能表达神经细胞标示物MAP2或星形胶质细胞标志物GFAP,并伴随着明显的细胞形态的改变。用RA诱导以及在无血清的培养基中培养,BMSCs主要分化成神经元样细胞,表达神经元的标志物MAP2,并且BME能促进这个过程。但在和星形胶质细胞共培养后,BMSCs主要分化成GFAP+细胞。结论BMSCs依赖于不同的诱导条件,具有分化成神经细胞或星形胶质细胞的可塑性。     

Short Duration Electrical Stimulation to Enhance Neurite Outgrowth and Maturation of Adult Neural Stem Progenitor Cells

New therapies are desperately needed for human central nervous system (CNS) regeneration to circumvent the lack of innate regenerative ability following traumatic injuries. Previously attempted therapies have been stymied by barriers to CNS regeneration largely because of protective mechanisms such as the blood brain barrier, inhibitory molecules, and glial scar formation. The application of electric stimulation (ES) has shown promise for enhancing peripheral nervous system regeneration, but is in its infancy in CNS regeneration. The objective of this study is to better understand how short duration ES can be harnessed to direct adult neural stem progenitor cell (NSPC) neurogenesis, neurite extension, and maturation. Herein, NSPCs were exposed to physiological levels of electrical stimulation of 0.53 or 1.83 V/m (applied power supply setting of 1.2 and 2.5 V) of direct current (DC) for 10 min/days for 2 days with a total differentiation time of 3 days. Culturing conditions consisted of either mitogenic growth factors or the neuronal differentiation factor interferon-γ (IFN-γ). Stimulated NSPCs showed lengths that were over five times longer than unstimulated controls (112.0 ± 88.8 μm at 0.53 V/m vs. 21.3 ± 8.5 μm for 0 V/m with IFN-γ) with the longest neurites reaching up to 600 µm. Additionally, ES resulted in mature neuronal morphologies and signs of differentiation through positive βIII tubulin, neuronal nuclei (NeuN), and better organized filamentous-actin (f-actin) staining with growth cone formation. Additionally, the neurites and soma of stimulated NSPCs showed increases in intracellular Ca²⁺ during stimulation, signifying the presence of functional neurons capable of electrical conductance and communication with other cells. Our study demonstrates that short stimulation times (10 min/ day) result in significant neurite extension of stem cells in a quick time frame (3  days). This ES modality is potentially advantageous for promoting axon re-growth at an injury site using delivered adult stem cells; however, significant work still remains to understand both the delivery approach of cells as well as ES application in vivo.     

大鼠胚胎神经干细胞的纯化、诱导分化及鉴定

探讨胚胎神经干细胞 (Neural stem cell,NSCs)的体外纯化扩增、保存标记、诱导分化及其鉴定方法。将14 .5 d胎龄大鼠大脑额叶皮质 NSCs在无血清 DMEM/ F12 (含 2 0 ng/ ml b FGF,2 0 ng/ m l EGF及 B2 7辅助培养液 )培养 ,利用有限稀释法将悬浮生长的单个细胞所形成的克隆球挑选出来、通过亚克隆连续传代大量扩增而纯化 ,免疫组化鉴定 nestin抗原阳性 ;选取部分 NSCs冻存、复苏后 nestin抗原阳性 ;用 Brd U孵育 NSCs,被 Brd U标记的 NSCs及其血清诱导分化后仍均呈 Brd U阳性。用血清或饲养层诱导 NSCs分化为大量表达 Tubulin- (神经元特异性抗原微管蛋白 3)阳性的神经元和 GFAP(神经胶质纤维酸性蛋白 )阳性的神经胶质细胞。由该实验可知有限稀释单细胞克隆连续传代是分离纯化、大量扩增胚胎期大脑 NSCs的简单有效方法。饲养层细胞也能诱导 NSCs分化为神经细胞。 Brd U可标记、示踪神经系统疾病动物模型 NSCs的实验治疗。掌握 NSCs的体外纯化培养、保存标记、诱导分化及鉴定方法可为进一步研究 NSCs的生物学特性及神经系统疾病的治疗提供新方法。     

Ultrasound Effect on Neural Differentiation of Gingival Stem/Progenitor Cells

Dental pulp loss due to caries or pulpitis can affect the longevity of teeth. Dental pulp tissue engineering necessitates the use of progenitor cells that has the potential to differentiate into neural, vascular and odontoblasts like cells. Previous reports have shown that human gingival progenitor cells (HGPCs) can be differentiated into different cell types; however neural differentiation of these cells, to the best of our knowledge, has not been reported. Low intensity pulsed ultrasound (LIPUS) has been reported to enhance cell differentiation. The aims of this study were (1) to explore the potential neural differentiation of HGPCs and (2) to investigate the effect of LIPUS on the differentiation of HGPCs when incubated under neuroinductive conditions. The HGPCs were isolated from human interdental papilla proximal to the premolar teeth that were extracted for orthodontic purpose. The HGPCs were induced to differentiate into neural lineage using a neuroinductive culture medium. HGPCs were divided into four groups; control group, neuro-induction (NI) group, ultrasound group (LIPUS), and a combined NI+LIPUS group. HGPCs were harvested for immunostaining and q-PCR after 1 day. Immunostaining for neuron specific antigens and q-PCR suggested that HGPCs can be differentiated into neural lineage and that selected neurodifferentiation markers can be enhanced by LIPUS.     

胰岛素对大鼠神经干细胞增殖和分化的影响

目的探讨胰岛素对大鼠神经干细胞(NSCs)增殖和分化的影响。方法培养大鼠大脑皮层NSCs,用胰岛素作用于培养的NSCs,3H-TdR掺入检测NSCs的增殖,免疫细胞化学和流式细胞仪检测NSCs的分化。结果胰岛素能明显促进NSCs对3H-TdR的摄入,明显促进细胞的增殖,并且胰岛素促细胞增殖作用具有一定的量效关系;免疫细胞化学和流式细胞仪结果显示,胰岛素对NSCs向神经元的分化有明显促进作用,并且NSCs分化后多巴胺能神经元数目明显增加。结论胰岛素可能具有促进NSCs增殖和向神经元包括多巴胺能神经元分化的作用。     

An Overview of Neural Differentiation Potential of Human Adipose Derived Stem Cells

There is wide interest in application of adult stem cells due to easy to obtain with a minimal patient discomfort, capable of producing cell numbers in large quantities and their immunocompatible properties without restriction by ethical concerns. Among these stem cells, multipotent mesenchymal stem cells (MSCs) from human adipose tissue are considered as an ideal source for various regenerative medicine. In spite of mesodermal origin of human adipose-derived stem cells (hADSCs), these cells have differentiation potential toward mesodermal and non-mesodermal lineages. Up to now, several studies have shown that hADSCs can undergo transdifferentiation and produce cells outside of their lineage, especially into neural cells when they are transferred to a specific cell environment. The purpose of this literature review is to provide an overview of the existing state of knowledge of the differentiation potential of hADSCs, specifically their ability to give rise to neuronal cells. The following review discusses different protocols considered for differentiation of hADSCs to neural cells, the neural markers that are used in each procedure and possible mechanisms that are involved in this differentiation.     

嗅鞘细胞/细胞外基质夹层支架的制备和形态学观察

目的研究嗅粘膜嗅鞘细胞在细胞外基质夹层支架内的生长特性,为治疗神经系统损伤寻找新的移植供体。方法嗅鞘细胞/细胞外基质夹层支架由四层毯状细胞外基质支架和三层嗅粘膜嗅鞘细胞相间叠加构成。纤维蛋白原、层粘连蛋白和纤粘连蛋白按一定比例混合后,在新鲜大鼠血浆促凝作用下,构建单层毯状细胞外基质支架,在支架表面种植嗅粘膜来源的嗅鞘细胞。于倒置显微镜下观察嗅鞘细胞在支架上/内的生长过程,培养3d后,在细胞表面再次滴加上述细胞外基质混合胶以构建第二层毯状支架,依次重复两次。夹层支架制成组织切片和超薄切片后,用光镜和电镜观察和分析夹层支架的内部结构以及嗅鞘细胞在支架内的生长情况。结果由顶层至底层,支架内的嗅鞘细胞数量逐渐增多,细胞突起逐渐延长,细胞内分泌颗粒逐渐增多及其电子密度逐渐增高;细胞可在支架之间迁移,其水平排列方向具有一致性;嗅鞘细胞的细胞膜可与支架紧密粘附,支架内局部区域出现组织间隙。结论嗅粘膜嗅鞘细胞可在细胞外基质夹层支架内正常增殖和分化,细胞与支架具有良好的组织相容性。该夹层支架可作为嗅鞘细胞三维生长的载体,用于移植治疗神经损伤。     

Preparation of Human Olfactory Ensheathing Cells for the Therapy of Spinal Cord Injuries

Bulletin of Experimental Biology and Medicine - We developed an optimal protocol for preparing and culturing of olfactory ensheathing cells from human olfactory mucosa. Using this protocol, we...     

新生大鼠海马神经干细胞的分离培养及分化研究

研究新生大鼠海马区脑组织中神经干细胞体外培养方法,为治疗神经系统疾病寻找合适的细胞来源。取新生SD大鼠的海马区脑组织,采用accutase结合机械分离法获取神经干细胞,在含有B－27、碱性成纤维生长因子和表皮生长因子的DMEM／F12无血清培养液中培养;Accutase酶消化后传代培养,取第3代细胞行抗巢蛋白免疫荧光染色鉴定并以含10％胎牛血清培养液诱导分化,神经元特异烯醇化酶和胶质纤维酸性蛋白免疫荧光染色检测NSCs向神经元及胶质细胞分化的能力。分离的新生大鼠海马区脑组织中细胞,在无血清培养液中形成大量的神经球,部分神经球出现融合及贴壁分化现象,细胞呈典型NSCs 形态。经巢蛋白染色鉴定,大部分为阳性细胞。神经细胞球经含有胎牛血清培养液培养后,可分化为神经元特异烯醇化酶和胶质纤维酸性蛋白表达阳性的细胞。从新生大鼠海马组织分离培养的NSCs具有自我更新和增殖能力,在含胎牛血清培养液中具有向神经元和神经胶质细胞分化的潜能。     

Pluripotent Stem Cells as a Robust Source of Mesenchymal Stem Cells

Mesenchymal stem cells (MSC) have been extensively studied over the past years for the treatment of different diseases. Most of the ongoing clinical trials currently involve the use of MSC derived from adult tissues. This source may have some limitations, particularly with therapies that may require extensive and repetitive cell dosage. However, nowadays, there is a staggering growth in literature on a new source of MSC. There is now increasing evidence about the mesenchymal differentiation from pluripotent stem cell (PSC). Here, we summarize the current knowledge of pluripotent-derived mesenchymal stem cells (PD-MSC). We present a historical perspective on the subject, and then discuss some critical questions that remain unanswered.     

The Immunohistochemical Characterization of Human Fetal Olfactory Bulb and Olfactory Ensheathing Cells in Culture as a Source for Clinical CNS Restoration

Clinical studies have expanded the therapeutic olfactory ensheathing cells (OECs) transplantation to different human Central Nervous System (CNS) diseases. In fact, the OEC transplantation in clinic is a mixture of olfactory bulb cells; they even have not demonstrated that they have such a subpopulation yet. However, as a source of OECs transplantation, the development and identification of human fetal OECs are still need more understanding, because some surgery try to restoration CNS injury with a more purity of OEC cultures generated by a number of different procedures. In this article, twelve human fetal olfactory bulb (OB) samples were obtained from six fetuses in 20 weeks of gestation, it was studied by immunofluorescence on histological sections and cultured cells with multiple antibodies under confocal microscopy. The P75NTR positive OB‐OECs (olfactory ensheathing cell from the olfactory bulb) were present in both outer olfactory nerve layers and glomerular layer. The percentage of OB cells in culture, about 22.31 was P75NTR positive, 45.77 was S100β, and 31.92 was GFAP. P75NTR and GFAP were coexpressed with S100β, respectively; however, P75NTR was not coexpressed with GFAP in human fetal OECs. It is suggested that the localization and development of human OECs in OB are different to those in rodent, and the P75NTR immunohistological staining is still necessary to identify and characterize human fetal OECs in culture before transplantation. Anat Rec, 2010. © 2009 Wiley‐Liss, Inc.     

Robust Enhancement of Neural Differentiation from Human ES and iPS Cells Regardless of their Innate Difference in Differentiation Propensity

Our analyses of three human induced pluripotent stem cell (hiPSC) and six human embryonic stem cell (hESC) lines showed marked variability in differentiation potential into specific lineages, which often hampers their differentiation into specific cell types or cell lineages of interest. Simultaneous inhibition of both Activin/Nodal and BMP pathways with small molecules, SB431542 and dorsomorphin (DM), respectively, promoted significant neural differentiation from all human pluripotent stem cell (hPSC) lines tested, regardless of their differentiation propensity. On the contrary, differentiation into other cell lineages and the number of undifferentiated cells were significantly reduced after differentiation by the dual inhibition. These results demonstrate that innate differentiation propensity of hPSCs could be overcome, at least in part, by modulation of intracellular signaling pathways, resulting in efficient generation of desirable cell types, such as neural cells.     

不同鼠龄生后大鼠海马神经干细胞的传代和分化

目的研究不同鼠龄大鼠海马神经干细胞(NSCs)的传代增殖和分化情况。方法将生后SD大鼠分为3d、10d、20d 3组,应用胰酶消化法将海马组织制成单细胞悬液,用含碱性成纤维生长因子(bFGF)、表皮生长因子(EGF)、B27的无血清细胞培养技术进行体外培养,单克隆培养后通过Nestin、NSE、GFAP免疫细胞化学染色鉴定神经干细胞、神经元、星形胶质细胞;细胞传3代后,在各组培养基中加入终浓度为10%的血清诱导分化,1周后进行NSE免疫细胞化学染色,计数阳性细胞比例,进行统计学分析。结果3组SD大鼠海马组织细胞,单克隆培养后表达Nestin,诱导分化后分别表达NSE和GFAP。生后3d大鼠神经干细胞在传1-6代时每代均快于生后10d和20d大鼠,传6代后,3组细胞传代时间间隔几近一致;生后3d组大鼠海马神经干细胞分化为神经元的比例较其它2组高(P<0.05)。结论生后3d大鼠神经干细胞增殖速度和分化为神经元的数量都高于10d和20d大鼠。     

褪黑素促进体外缺氧的神经干细胞增殖及定向分化

目的:观察褪黑素对体外缺氧诱导的小鼠神经干细胞(neural stem cells,NSCs)增殖和分化的影响。方法:取孕12.5 d胚胎小鼠大脑皮质分离培养NSCs,建立缺氧模型。利用免疫荧光染色,检测分析褪黑素对缺氧诱导后不同时间点的NSCs增殖和分化的影响。结果:缺氧后NSCs的增殖能力明显下降,而褪黑素可显著改善这一现象,促进缺氧后NSCs的增殖。缺氧后NSCs向神经元的分化明显受阻,褪黑素处理组的神经元的分化率明显高于对照组,其中作用高峰期是分化的第七天。结论:体外缺氧的NSCs增殖和分化均明显受到抑制,而褪黑素的干预可明显改善干细胞的增殖,促进NSCs向神经元的分化,但对星形胶质细胞的分化没有显著影响。