BMSCs体外培养与向神经元样细胞诱导分化的研究进展

骨髓间充质干细胞(bone marrnw mesenchymal stem cells,BMSCs)是来源于骨髓组织中的非造血细胞,具有来源容易获取、不受伦理限制,广泛的增殖分化能力,易于分离、培养、扩增、纯化,免疫原性弱,免疫耐受性强,体外基因转染率高,并能稳定高效的表达外源基因等优点.因此,BMSC成为一种比较理想的种子细胞,BMSC由于能向神经细胞这种几乎不可再生细胞的分化能力,更是成为研究的热点.近年来BMSCs的体外诱导向神经元样细胞分化的方法和可能的机制取得了很多新的进展和成果,本文就BMSCs体外培养诱导向神经元样细胞分化的进展作一综述.     

诱导人骨髓间充质干细胞向成骨细胞分化

目的探讨人骨髓间充质干细胞(mesenchymal stem cells，MSCs)向成骨细胞诱导分化的能力。方法选用不同代次的MSCs，使用条件培养基，观察细胞的形态变化，采用细胞化学和免疫组化的方法检测碱性磷酸酶、钙盐沉积及Ⅰ型胶原的表达。结果MSCs在条件培养基中，15d后可见细胞变为多边形，碱性磷酸酶和Ⅰ型胶原染色阳性，形成钙结节，表现成骨细胞分化特点。结论在一定培养条件下成功诱导人MSCs向成骨细胞分化。在骨组织工程学方面MSCs作为种子细胞具有潜在的应用价值。     

间充质干细胞膜微粒的临床应用研究进展

由于干细胞具有自我更新和分化为其他类型细胞的能力,因此,干细胞在临床上的应用也越来越广泛。而间充质干细胞(mesenchymal stem cells,MSCs)不仅具有自我更新的能力,而且具有多向分化潜能,在不同的诱导条件下可以分化为不同组织[1],同时,MSCs来源方便,易于分离、培养、扩增和纯化,多代扩增后仍具有干细胞特性,不存在免疫排斥,体外基因转染率高并能稳定     

体外长期培养的家猪骨髓间充质干细胞生物学特性变化

目的 观察体外长期培养的家猪骨髓间充质干细胞(marrow mesenchymal stem cells,MSCs)生物学特性的变化.方法 将第1代MSCs(早期)和第35代MSCs(晚期)分别进行细胞形态学观察和染色体核型分析;钙沉积和细胞增殖测定,以及采用实时定量PCR定量分析成骨分化及成脂分化相关基因表达.结果 早期培养的MSCs细胞形态为较大的纺锤形,晚期为小的梭形.第35代MSCs细胞Ki-67染色强阳性,染色体数目增加.成骨诱导条件下早期MSCs茜素红S染色呈强阳性,晚期MSCs未见明显染色且OC基因表达明显下调(P＜0.01);成脂诱导条件下早期MSCs油红O染色阳性,晚期MSCs未见明显染色且PPARγ2基因表达明显下调(P＜0.01).结论 体外长期培养的家猪晚期MSCs不适合作为组织工程种子细胞.     

成人骨髓间充质干细胞体外向视网膜细胞的诱导分化

目的研究取材于成人骨髓的间充质干细胞在一定诱导条件下向视网膜神经细胞的分化。方法成人骨髓经密度梯度离心得到的细胞,根据其高黏附特性体外培养获得间充质干细胞。利用流式细胞仪分析其细胞表型,在体外诱导使其向视网膜神经细胞分化并用免疫荧光法进行鉴定。结果从骨髓中分离培养的细胞具有成纤维细胞样形态,贴壁生长,表型相对均一,表面标志为CD90、CD44、CD147阳性;而CD34、CD38、CD45、CD14、HLA-DR阴性。体外诱导后可以得到表达nestin(神经干细胞标志物)、GFAP(神经胶质细胞标志物)和Rhodopsin(视网膜光感受器细胞标志物)阳性的细胞。结论从人骨髓中分离培养得到的间充质干细胞具有向视网膜神经细胞分化的潜能。     

骨髓间充质干细胞向神经细胞分化及移植研究进展

骨髓间充质干细胞(mesenchymalstemcells,MSCs)又称骨髓基质细胞(bonemarrowstromal cells,BMSCs),是干细胞研究的又一新的发现,是目前干细胞研究的热点和前沿。MSCs具有方便获取、易于分离培养和扩增纯化,在体外培养条件下多代扩增后仍保持多向分化潜能的特点,且遗传背景稳定,     

骨髓间充质干细胞分化为神经元样细胞的研究进展

无论是在体外实验还是在体内实验,骨髓间充质干细胞(Bone marrow mesenchymal stem cells,BMSCs)都可以向中枢神经系统(CNS)神经细胞分化,但争议颇多。因为功能性神经元不仅要具有典型神经元的形态、特异性标记,还要求具有可兴奋性、能和其他神经元形成突触联系、产生突触电位等,所以对骨髓间充质干细胞是否能诱导出真正具有功能的神经元存在很大分歧。在此对BMSCs向神经细胞诱导分化研究的现状、存在的问题及发展前景给予综述。     

体外诱导大鼠骨髓间充质干细胞为血管内皮细胞的研究

目的研究骨髓间充质干细胞（mesenchymal stem cells，MSCs）定向分化为血管内皮细胞，为组织工程血管化及细胞移植修复损伤组织提供理想的细胞来源。方法贴壁法分离SD大鼠MSCs进行体外培养和连续传代，采用第四代MSCs，以血管内皮生长因子（vascular endothelial growth factor，VEGF）和碱性成纤维细胞生长因子（basic fibroblast growth facotr，bFGF）进行体外诱导，免疫荧光染色方法鉴定内皮细胞，并通过透射电镜观察内皮细胞W-P小体。结果免疫荧光染色证实实验组细胞阳性表达，透射电镜观察到内皮细胞特有的WP小体。结论MSCs可以在体外定向分化为具有血管内皮细胞特性的细胞。     

人参皂苷Rg1通过miR-138-5p/SIRT1轴诱导骨髓间充质干细胞向髓核样细胞增殖分化

目的 探讨人参皂苷Rg1诱导大鼠骨髓间充质干细胞(bone marrow mesenchymal stem cells,BMSCs)向髓核样细胞(nucleus pulposus cells,NPCs)分化的机制.方法 从成年SD大鼠中分离培养BMSCs.通过CCK-8法检测不同浓度人参皂苷Rg1(0,2.5,5,10...     

间充质干细胞研究进展及其临床应用前景

间充质干细胞（mesenchymal stem cells,MSCs）通常是指从骨髓或其他组织中分离到的在体外具有多向分化潜能的一类细胞。自Friedenstein等首次报道骨髓中有少量细胞在培养过程中能贴壁分化形成类似骨、软骨的集落后,人们对这些细胞产生了浓厚兴趣。随后从鼠、兔、犬、人等多种动物的骨髓中均分离到了这种贴壁细胞。它们具有多向分化潜能,在体外不同诱导条件下可分化为成骨细胞、软骨细胞、脂肪细胞及神经细胞。     

Defined culture medium for stem cell differentiation: Applicability of serum-free conditions in the mouse embryonic stem cell test

The embryonic stem cell test (EST) is a validated method to assess the developmental toxicity potency of chemicals. It was developed to reduce animal use and allow faster testing for hazard assessment. The cells used in this method are maintained and differentiated in media containing foetal calf serum. This animal product is of considerable variation in quality, and individual batches require extensive testing for their applicability in the EST. Moreover, its production involves a large number of foetuses and possible animal suffering. We demonstrate the serum-free medium and feeder cell-free maintenance of the mouse embryonic stem cell line D3 and investigate the use of specific growth factors for induction of cardiac differentiation. Using a combination of bone morphogenetic protein-2, bone morphogenetic protein-4, activin A and ascorbic acid, embryoid bodies efficiently differentiated into contracting myocardium. Additionally, examining levels of intracellular marker proteins by flow cytometry not only confirmed differentiation into cardiomyocytes, but demonstrated significant differentiation into neuronal cells in the same time frame. Thus, this approach might allow for simultaneous detection of developmental effects on both early mesodermal and neuroectodermal differentiation. The serum-free conditions for maintenance and differentiation of D3 cells described here enhance the transferability and standardisation and hence the performance of the EST.     

5-氮胞苷诱导心肌组织中c-kit~+干细胞分化的实验研究

目的:创建小鼠心肌干细胞(cardiac stem cells,CSC)分离、培养的方法,借助干细胞表面标记c-kit纯化CSC,并用5-氮胞苷诱导CSC分化为心肌细胞。方法:用酶定时消化方法分离提取小鼠心脏组织中的细胞,进行体外培养;免疫磁珠法纯化c-kit阳性细胞,并用流式细胞仪检测纯化后细胞表面标记c-kit、lin和CD34的表达;以免疫细胞化学染色法检测诱导后心肌特异性蛋白T、连接蛋白-43、心肌细胞特异性结蛋白;结合形态学变化,分析不同诱导条件作用结果之间的差异。结果:从C57BL小鼠心肌组织中分离消化所得的细胞中,含有一种小而圆形、折光性强的细胞,经传代培养的细胞增殖速度比原代细胞明显为快,存在较多的类似于干细胞增殖和形态学特点的细胞。用免疫磁珠法可以分选出高纯度的c-kit+CSC,这种CSC基本不表达CD34和lin。在不同诱导条件下,此种CSC可以分化为搏动的细胞,并能表达心肌特异性蛋白。结论:从C57BL小鼠心肌组织中可以获得CSC,用免疫磁珠法可以分选出表型为c-kit+-CD34--lin-高纯度的CSC,经5-氮胞苷诱导或改变CSC生长的微环境后,此种细胞可以分化成心肌细胞,且能形...     

In vitro developmental toxicity test detects inhibition of stem cell differentiation by silica nanoparticles

While research into the potential toxic properties of nanomaterials is now increasing, the area of developmental toxicity has remained relatively uninvestigated. The embryonic stem cell test is an in vitro screening assay used to investigate the embryotoxic potential of chemicals by determining their ability to inhibit differentiation of embryonic stem cells into spontaneously contracting cardiomyocytes.Four well characterized silica nanoparticles of various sizes were used to investigate whether nanomaterials are capable of inhibition of differentiation in the embryonic stem cell test. Nanoparticle size distributions and dispersion characteristics were determined before and during incubation in the stem cell culture medium by means of transmission electron microscopy (TEM) and dynamic light scattering.Mouse embryonic stem cells were exposed to silica nanoparticles at concentrations ranging from 1 to 100 μg/ml. The embryonic stem cell test detected a concentration dependent inhibition of differentiation of stem cells into contracting cardiomyocytes by two silica nanoparticles of primary size 10 (TEM 11) and 30 (TEM 34) nm while two other particles of primary size 80 (TEM 34) and 400 (TEM 248) nm had no effect up to the highest concentration tested.Inhibition of differentiation of stem cells occurred below cytotoxic concentrations, indicating a specific effect of the particles on the differentiation of the embryonic stem cells. The impaired differentiation of stem cells by such widely used particles warrants further investigation into the potential of these nanoparticles to migrate into the uterus, placenta and embryo and their possible effects on embryogenesis.     

骨髓干细胞移植治疗缺血性心脏病的研究进展

干细胞具有自我更新，多向分化能力，在适宜的体外培养中干细胞能够稳定生存增殖并保持多向分化潜能，是便于体外操作的理想的靶细胞。本综合近几年国内外献，阐述了骨髓干细胞通过移植技术移植至试验动物的病损心脏，可以分化增殖为心肌细胞和血管结构，从而改善缺血的心脏功能。因此具有广阔的临床应用前景，值得进一步研究。     

Cardiac repair by embryonic stem-derived cells

Cell transplantation approaches offer the potential to promote regenerative growth of diseased hearts. It is well established that donor cardiomyocytes stably engraft into recipient hearts when injected directly into the myocardial wall. Moreover, the transplanted donor cardiomyocytes participate in a functional syncytium with the host myocardium. Thus, transplantation of donor cardiomyocytes resulted in at least partial restoration of lost muscle mass. It is also well established that embryonic stem (ES) cells differentiate into cells of ecto-, endo-, and mesodermal lineages when cultured under appropriate conditions in vitro. Robust cardiomyogenic differentiation was frequently observed in spontaneously differentiating ES cultures. Cellular, molecular and physiologic analyses indicated that ES-derived cells were bona fide cardiomyocytes, with in vitro characteristics typical for cells obtained from early stages of cardiac development. Thus, ES-derived cardiomyocytes constitute a viable source of donor cells for cell transplantation therapies.     

光电成像系统在评价胚胎干细胞体外定向分化为心肌细胞中的应用

目的采用简易光电成像系统记录胚胎干细胞(ES细胞)体外定向分化心肌细胞的搏动频率,为药物诱导ES细胞体外定向分化心肌细胞提供量化评价指标。方法以简易光电成像系统记录心肌细胞搏动频率,并以维A酸和淫羊藿苷诱导ES细胞定向分化心肌细胞为例,收集分化过程中发育依赖性基因(α-肌球蛋白重链、心室肌球蛋白轻链及β-肾上腺素受体)和心肌特异性蛋白(α-辅肌动蛋白和肌钙蛋白T)表达情况,同步分析光电成像信号与分子生物学指标的一致性。结果光电成像系统可灵敏反映分化心肌细胞的搏动频率,在与维A酸和淫羊藿苷共培养体系中,搏动频率与心肌发育依赖性基因、蛋白表达和β-肾上腺素受体形成等一致,可体现心肌分化的不同时间段。结论简易光电成像系统能灵敏记录ES细胞定向分化心肌细胞的搏动频率,此搏动频率与细胞分化成熟程度一致,可望成为药物诱导分化心肌细胞初步评价的量化指标。     

Peptidomimetic small-molecule compounds promoting cardiogenesis of stem cells

Embryonic stem (ES) cells may be used as an alternative source of functionally intact cardiomyocytes for ischemic heart disease. Several natural and synthetic small molecules have been identified as useful tools for controlling and manipulating stem cell renewal and differentiation. Currently, there is an urgent requirement for novel small molecules that specifically induce differentiation of stem cells into cardiomyocytes. To identify compounds that promote cardiomyogenesis of stem cells, cell-based screening of a peptidomimetic small-molecule library was carried out. A series of ??-turn peptidomimetic compounds, including CW209E, increased the expression of ??-MHC promoter-driven enhanced green fluorescent protein (EGFP) and ratio of beating embryoid bodies (EBs) without inducing cytotoxicity in mouse embryonic stem cells. CW209E also increased the number of beating EBs in human embryonic stem cells (hESCs) and human induced pluripotent stem cells (hiPSCs). Thus, this chemical compound should be useful for elucidation of the molecular pathway of cardiogenesis and generation of cardiomyocytes ex vivo, which can be further applied for experimental or clinical cell therapy for ischemic heart diseases.     

川续断皂苷Ⅵ诱导大鼠骨髓间充质干细胞向成骨细胞方向分化的研究

目的探讨川续断皂苷Ⅵ(akebia saponin D)对大鼠骨髓间充质干细胞(MSCs)定向诱导分化为成骨细胞的影响。方法用密度梯度离心结合贴壁培养法分离纯化大鼠骨髓MSCs,选择合适的培养基,传代扩增。采用不同浓度的川续断皂苷Ⅵ对大鼠MSCs定向诱导分化,MTT法观察各组对MSCs的增殖作用并绘制细胞生长曲线;观察MSCs诱导分化过程中成骨细胞内碱性磷酸酶(alkaliphosphatase,ALP)活性;采用ELISA法检测MSCs诱导分化过程中骨钙素(Osteo-calcin,OC)的含量;RT-PCR方法检测MSCs诱导分化过程中核心结合因子α-1(Cbfα1)mRNA表达。结果细胞生长曲线显示各组MSCs数量均随时间延长而增加,中、高浓度的川续断皂苷Ⅵ能明显提高MSCs分化为成骨细胞的ALP活性和骨钙素的含量,且使Cbfα1 mRNA的表达升高。结论川续断皂苷Ⅵ具有促进大鼠体外MSCs向成骨细胞增殖和分化的作用,这一作用可能与其升高Cbfα1 mRNA的表达有关。