重编程人皮肤成纤维细胞为iPS细胞的研究

目的探讨高效建立人多能性细胞的方法。方法利用经典的Yamanaka方法及Oct4病毒的重复感染,诱导人皮肤成纤维细胞为诱导的多能性干(iPS)细胞。通过AKP染色及分化能力,验证其多潜能特性。结果通过Oct4病毒的重复感染,将人皮肤成纤维细胞重编程为iPS细胞;所建立的iPS细胞AKP染色阳性,免疫缺陷裸鼠的皮下获得了含三胚层结构的畸胎瘤。结论通过Oct4病毒的重复感染,成功的将人皮肤成纤维细胞重编程为iPS细胞。     

鼠星形胶质细胞重编程为诱导多潜能干细胞的研究

目的研究星形胶质细胞重编程为诱导多潜能(iPS)干细胞的可行性,为进一步研究iPS细胞诱导技术奠定基础。方法用分别含Oct4,Sox2,Klf4和c-myc因子的4种逆转录病毒载体病毒颗粒感染星形胶质细胞,获得iPS细胞并进行鉴定。结果感染后第28天具有胚胎干细胞形态的克隆出现,诱导效率为(0.015±0.005)%,且碱性磷酸酶(AP)染色及SSEA-1和Oct4免疫荧光染色均显阳性。结论星形胶质细胞可以重编程为iPS细胞,进一步证明了iPS细胞诱导技术的普遍适用性。     

小鼠骨髓间充质干细胞、骨髓单核细胞和胚胎成纤维细胞重编程为诱导性多能干细胞的效率比较

目的比较小鼠骨髓间充质干细胞(BMSCs)、小鼠骨髓单核细胞(BM-MNCs)和小鼠胚胎成纤维细胞(MEFs)重编程为诱导性多能干细胞(iPS细胞)的效率。方法用慢病毒LV-ef1a-mOct4-IRES-EGFP、LV-ef1a-mSox2-IRES-EGFP、LV-ef1a-mKlf4-IRES-EGFP和LV-ef1a-mc-Myc-IRES-EGFP感染BMSCs、BM-MNCs和MEFs,通过计算碱性磷酸酶染色阳性克隆数比较这3种细胞重编程为iPS细胞的效率。用胚胎干细胞表面标记检测、胚胎干细胞内源基因检测、拟胚体形成实验和畸胎瘤形成实验验证重编程获得的iPS细胞的多能性。结果起源于小鼠BMSCs、BM-MNCs及MEFs的3种iPS细胞均能形成边缘光整的致密克隆,可表达干性基因Nanog、Rex-1、SSEA-1,并能在体内外分化为三胚层组织。但是BMSCs来源的碱性磷酸酶阳性克隆数低于BM-MNCs和MEFs来源的克隆数。结论小鼠BMSCs、BM-MNCs及MEFs均可重编程为iPS细胞,但BMSCs重编程为iPS细胞的效率低于BM-MNCs和MEFs。     

利用慢病毒载体构建稳定干扰β-catenin的人胚胎干细胞系

目的建立β-catenin稳定干扰的人胚胎干细胞系。方法利用β-catenin慢病毒干扰质粒PLKO.1-puro-β-catenin转染包装细胞293FT制备重组慢病毒,并感染人胚胎干细胞,采用嘌呤霉素筛选稳定表达shβ-catenin人胚胎干细胞克隆;试验分为稳定转染β-catenin干扰质粒组(Shβ-catenin)、稳定转染空白载体组(VECTOR)和对照未感染组(WT)三组,RT-PCR检测干扰后β-catenin mRNA表达;进一步免疫荧光检测干扰后细胞β-catenin和OCT4的蛋白表达。结果β-catenin特异性shRNA的慢病毒感染人胚胎干细胞后,获得稳定表达shβ-catenin的人胚胎干细胞系,Shβ-catenin组β-catenin mRNA表达明显降低,只有WT组mRNA表达的1%,而VECTOR组和WT组之间无明显差异;免疫荧光染色进一步验证shβ-catenin组中基本无β-catenin蛋白的表达,但表达多能性标记OCT4。结论通过β-catenin特异性shRNA慢病毒载体构建了稳定干扰β-catenin的人胚胎干细胞系。     

重编程肝癌细胞系Huh7为多潜能干细胞样细胞

[摘要] 目的 重编程肝癌细胞系Huh7细胞为多潜能干细胞。方法 包装携带有Oct4、Sox2、Nanog、Lin28基因的慢病毒,将包装好的病毒共感染Huh7细胞,采用碱性磷酸酶染色、免疫荧光、实时定量PCR,免疫组织化学等方法对诱导出的多潜能干细胞样克隆细胞进行鉴定。结果 Huh7细胞被重编程为多潜能干细胞样细胞,碱性磷酸酶染色呈阳性,免疫荧光实验证明其表达多潜能因子,Oct4与TRA-1-60,qPCR实验证明其高水平表达内源性的多潜能相关基因及干细胞特异的microRNAs,体内分化实验结果表明iHuh7可以形成畸胎瘤。结论 通过携带四种多潜能因子的慢病毒介导的重编程, Huh7细胞可以被诱导为多潜能干细胞样细胞。     

诱导性建立多能干细胞系

目的建立多能干细胞系,并鉴定其是否具有正常于细胞的特性。方法将原代皮肤标本用胶原酶消化处理,利用成纤维细胞培养基进行培养,然后感染病毒。对挑选的人成体细胞来源的iPS克隆进行扩大培养,并对克隆进行免疫荧光检测和lit-PCR检测,确定表达的分子标志,采用体外三胚层分化来鉴定其生物学特性。结果所获得的iPS细胞经鉴定具有碱性磷酸酶活性。并表达Nanog、SSEA-4、Sox2、TRA-1-60等干细胞特异标记物,可形成拟胚体并在体内外可以分化为三胚层的细胞类型。结论成功建立了iPS细胞系,为今后的研究提供了良好的细胞模型。     

Sox2、Klf4、Oct4、c-Myc基因编程脐带基质间充质细胞

目的 探讨利用Sox2、Klf4、Oct4、c-Myc基因将脐带基质间充质细胞（UMC）编程为多潜能干细胞（iPS）.方法 原代分离培养UMC细胞,包装生产逆转录病毒感染细胞,将感染后细胞接种到饲养层细胞培养,镜下观察细胞形态学变化.对编程后细胞进行碱性磷酸酶（AP）染色、检测细胞内源多能基因表达量和体内分化畸胎瘤实验.结果 原代获得UMC细胞,被编程细胞形态类似于胚胎干细胞,AP染色阳性,内源多能基因Oct4、Sox2、Nanog、Rex1表达量增高,体内分化为畸胎瘤.结论 利用Sox2、Klf4、Oct4、c-Myc基因可将UMC细胞编程为iPS细胞.     

慢病毒介导shRNA沉默巢蛋白表达对人黑色素瘤细胞转移特性的影响

摘要：目的应用慢病毒介导的RNA干扰技术,有效沉默黑色素瘤细胞株UACC903 巢蛋白（nestin）的表达,研究其对黑色素瘤
细胞转移能力的影响。方法以人nestin mRNA编码序列作为干扰靶点,以慢病毒基因PLL3.7 作为质粒载体,构建靶向人
nestin的shRNA表达质粒,另构建不针对任何已知mRNA的阴性对照shRNA表达质粒,分别感染UACC903细胞并流式分选获
得高纯度的nestin 干扰或对照组细胞。应用RT-PCR、免疫荧光及Western blotting 检测不同组别nestin 表达的变化。分别用
Transwell侵袭试验检测跨膜细胞的数量评估各组黑色素瘤细胞的侵袭能力,划痕法检测迁移能力改变。光镜观察各组细胞形
态变化,免疫荧光检测E-cadherin、N-cadherin 和β-catenin 在不同组别的表达变化。结果成功构建nestin shRNA慢病毒载体
nestin-RNAi-LV。RT-PCR 及免疫荧光结果显示干扰组UACC903 细胞nestin mRNA及蛋白表达水平较对照组显著降低。
nestin下调的UACC903细胞黏附、侵袭及迁移能力下降（P<0.05）。结论慢病毒介导的shRNA 能有效地静默食管癌细胞nestin
基因的表达,能抑制黑色素瘤细胞UACC903迁移。
     

核因子I-C 降低皮肤成纤维细胞对TGF-β的敏感性

目的探讨核因子I-C（NFI-C）对血小板源性生长因子（PDGF）促进皮肤成纤维细胞表达TGF-β受体Ⅱ（TβRⅡ）作用的影
响。方法含有NFI-C序列的慢病毒转染人皮肤成纤维细胞（HFF-1）;根据细胞生长活性及转染效率筛选最佳转染复数（MOI）;
PDGF-BB刺激体外培养的HFF-1细胞、转染NFI-C的HFF-1细胞以及转染阴性病毒的HFF-1细胞,并设立转染NFI-C但不用
PDGF处理的细胞;以不做任何处理的HFF-1 细胞作为空白对照组;采用western blot、RT-qPCR测定各组细胞TβRⅡ的表达。
数据采用单因素方差分析、LSD-t及SNK-q检验对各组数据进行分析。结果慢病毒转染HFF-1最适MOI为50。PDGF处理的
HFF-1细胞表达TβRⅡ高于空白对照组（P<0.05）;在PDGF作用下,转染NFI-C的HFF-1细胞表达TβRⅡ低于未转染的细胞（P<
0.05）;阴性病毒无明显抑制作用（P>0.05）;单纯转染NFI-C的HFF-1细胞表达TβRⅡ与空白对照组无显著性差异（P>0.05）。结
论NFI-C能抑制PDGF对TβRⅡ的上调作用,降低皮肤成纤维细胞对TGF-β的敏感性。
     

逆转录病毒方法建立小鼠诱导性多能干细胞的实验研究

[目的]采用逆转录病毒法转染P2代ICR的小鼠胚胎成纤维细胞(mouse embryonic fibroblast,MEF),建立小鼠诱导性多能干细胞(inducedpluripotent stem cell,iPS cell,iPS细胞)。[方法]本实验采用293T细胞进行逆转录病毒包装,将分别携带来源于人的Oct3/4、Sox2、c-Myc、Klf4转录因子的4种逆转录病毒液共转染ICR小鼠的MEF,并在转染过程中添加维生素C、丙戊酸钠来提高小鼠iPS细胞的诱导效率,通过碱性磷酸酶染色、RT-PCR方法检测建立的细胞株。[结果]转染的MEF在1周左右时间出现明显克隆,克隆传代的细胞经碱性磷酸酶染色呈紫红色,RT-PCR检测结果显示细胞株中的Oct3/4、Sox2、c-Myc、Klf4、Nanog 5种多能性相关的基因都得到明显表达。[结论]转染的MEF在1周左右时间出现明显克隆,小鼠iPS细胞的一些表面标志如碱性磷酸酶得到表达,Oct3/4、Sox2、c-Myc、Klf4、Nanog 5种多能性相关基因也都得到明显表达,表明已经建立小鼠iPS细胞。     

Therapeutic potential of motor neurons differentiated from embryonic stem cells and induced pluripotent stem cells

Degeneration of motor neurons (MN) caused by disease or injury leads to paralysis and is fatal in some conditions. To date, there are no effective treatments for MN disorders; therefore, cell therapy is a promising strategy to replace lost MN. Embryonic stem (ES) cells isolated from the inner cell mass of mammalian blastocysts self-renew and are pluripotent because they differentiate into cell types of the three germinal layers. Reprogramming of adult cells to a state similar to ES cells, termed induced pluripotent stem (iPS) cells, has been recently reported. It is well established that pluripotent cell types can give rise to specialized phenotypes, including neurons. Mouse, monkey and human MN can be differentiated from ES and iPS cells using procedures generally involving embryoid bodies formation and stimulation with retinoic acid and Sonic hedgehog. Differentiated MN express characteristic molecular markers such as Islet1, HB9 and Choline acetyltransferase, exhibit electrophysiological maturity and are able to form synaptic contacts similar to neuromuscular junctions in vitro. Furthermore, transplanted MN promote functional recovery in animal models of neurodegenerative diseases and MN injury. The potential clinical applications of stem cell-derived MN was enhanced after iPS cell derivation, which makes possible the generation of patient-specific pluripotent cells for autologous cell replacement therapies and may be used for drug development and disease modeling. This review summarizes MN differentiation protocols from ES and iPS cells in regard to neuronal differentiation efficiency, expression of MN markers and functional properties in vitro, as well as their therapeutic effects after grafting.     

猪naive-like诱导性多能干细胞系的建立及红色荧光蛋白标记

目的：建立猪naive-like诱导性多能干(induced pluripotent stem,iPS)细胞系,并对其进行红色荧光标记,为通过示踪猪naive iPS细胞发育和分化的相关研究奠定基础。方法：首先利用核转染技术向巴马小型猪胎儿成纤维细胞(porcine embryonic fibroblast,PEF)中转入鼠源OCT4、SOX2、KLF4和c-MYC转录因子表达载体TetO-FUW-OSKM,并同时转入激活表达载体FUW-M2rtTA,采用白血病抑制因子(leukemia inhibitory factor,LIF)结合碱性成纤维细胞生长因子(basic fibroblast growth factor,bFGF)的培养体系进行培养,通过在培养液中添加盐酸多西环素(doxycycline hyclate,DOX) 进行诱导,建立起猪iPS细胞系,并对细胞系的多能性进行鉴定。在此基础上,向iPS细胞系转入红色荧光蛋白表达载体,对其进行标记,并鉴定被红色荧光标记后的细胞是否仍然具有多能性。结果：所建立的iPS细胞系克隆呈三维立体生长,可以进行单细胞传代培养至30代以上,核型正常,碱性磷酸酶染色呈阳性,表达多种干细胞多能因子,利用LIF/STAT3信号通路维持其增殖,体外可分化形成表达三胚层相关基因的类胚体,为猪naive-like iPS细胞系。成功对所建立的iPS细胞系进行红色荧光标记,碱性磷酸酶染色和免疫荧光染色结果显示被红色荧光标记的iPS细胞的多能性依然存在。结论：成功建立了稳定表达红色荧光蛋白的猪naive-like iPS细胞系。     

肝癌患者脂肪干细胞重编程为诱导多潜能干细胞

目的重编程肝癌患者来源的脂肪干细胞为诱导多潜能干细胞。方法包装携带Oct4、Sox2、Klf4、c-Myc基因的反转录病毒,将病毒感染脂肪干细胞并培养诱导后的细胞,采用碱性磷酸酶染色、定量PCR和原位免疫荧光实验鉴定诱导的克隆样细胞。结果诱导的克隆样细胞表达碱性磷酸酶,定量PCR证实克隆样细胞表达胚胎干细胞多能性基因,免疫荧光实验证实其表达Oct4和Sox2。结论肝癌患者来源的脂肪干细胞可高效重编程为诱导多潜能干细胞,且脂肪干细胞可作为培养诱导多潜能干细胞的滋养细胞,为提高成体细胞重编程效率和建立基于诱导多潜能干细胞的肝癌模型研究提供了平台。     

诱导性多潜能干细胞的研究进展与应用

分化成熟的体细胞可在体外被重编程为诱导性多潜能干细胞,后者具有与胚胎干细胞相似的自我更新能力和发育多潜能性,同时避免了免疫排斥和伦理问题.患者特异性的诱导性多潜能干细胞将成为再生医学、药物筛选和毒理测试的理想工具.     

无bFGF条件下简便有效建立C57BL/6J小鼠胚胎干细胞系

目的:在不含bFGF的Knockout血清替代品(knockout serum replacement,KSR)的培养条件下,简便、有效地建立小鼠胚胎干细胞(embryonic stem cells,ES)系.方法:以C57BL/6J小鼠3.5天囊胚为材料,改良巴氏德管机械法分离内细胞团,于加或不加碱性成纤维细胞生长因...     

Development of neural precursor cells from mouse embryonic stem cells

Embryonicstemcells(EScells)arederivedfromtotipotentcellsofearlyembryoandpossessunlimited,undifferentiatedproliferationinvitro[1].EScellshavetheinherentcapacityofdifferentiatingintoallcelltypesofthenervoussystemasdemonstratedbytheex-perimentthatchimericmicewereformedfromem-bryosinwhichEScellsaretransplantedintotheinnercellmass[2].ThesuccessfulestablishmentofhumanEScelllineindicatedprofoundimplicationthatEScellsmayprovideavirtuallyunlimiteddonorsourcefortransplantation[3]. Threepaperspublish…     

Generation of Transgene-free Induced Pluripotent Stem Cells with Non-viral Methods

Induced pluripotent stem(iPS) cells were originally generated from mouse fibroblasts by enforced expression of Yamanaka factors(Oct3/4,Sox2,Klf4,and c-Myc).The technique was quickly reproduced with human fibroblasts or mesenchymal stem cells.Although having been showed therapeutic potential in animal models of sickle cell anemia and Parkinson’s disease,iPS cells generated by viral methods do not suit all the clinical applications.Various non-viral methods have appeared in recent years for application of iPS cells in cell transplantation therapy.These methods mainly include DNA vector-based approaches,transfection of mRNA,and transduction of reprogramming proteins.This review summarized these non-viral methods and compare the advantages,disadvantages,efficiency,and safety of these methods.     

诱导性多能干细胞技术的研究进展

诱导鼠成纤维细胞转变为多能干细胞的成功掀起了世界范围内诱导性多能干细胞(iPS)研究的热潮。iPS来源广泛,具有干细胞的分化全能性,避开了取材和应用的伦理问题,在医学领域具有广阔的应用前景,如构建人类疾病模型,用于特定细胞治疗,培育转基因动物用于器官移植以及生物制药等领域。目前iPS结合基因治疗和细胞移植疗法的成果已经应用到了动物疾病模型上。此外,该技术也为研究细胞重编程机制和人类疾病的病理过程提供了新平台。     

利用细胞因子和丁酸钠将小鼠诱导多能干细胞高效诱导为有功能的肝细胞

Background  Hepatocyte transplantation has been proposed as an alternative to whole-organ transplantation to support many forms of hepatic insufficiency. Unfortunately, the lack of donor livers makes it difficult to obtain enough viable human hepatocytes for hepatocyte-based therapies. Therefore, it is urgent to find new ways to provide ample hepatocytes. Induced pluripotent stem (iPS) cells, a breakthrough in stem cell research, may terminate these hinders for cell transplantation. For the promise of iPS cells to be realized in liver diseases, it is necessary to determine if and how efficient they can be differentiated into functional hepatocytes.      

Methods  In this study, we directly compared the hepatic-differentiation capacity of mouse iPS cells and embryonic stem (ES) cells with three different induction approaches: conditions via embryonic body (EB) formation plus cytokines, conditions by combination of dimethyl sulfoxide and sodium butyrate and chemically defined, serum free monolayer conditions. Among these three induction conditions, more homogenous populations can be promoted under chemically defined, serum free conditions. The cells generated under these conditions exhibited hepatic functions in vitro, including glycogen storage, indocynine green (ICG) uptake and release as well as urea secretion. Although efficient hepatocytes differentiation from mouse iPS cells were observed, mouse iPS cells showed relatively lower hepatic induction efficiency compared with mouse ES cells.

Results  Mouse iPS cells would be efficiently differentiated into functional hepatocytes in vitro, which may be helpful in facilitating the development of hepatocytes for transplantation and for research on drug discovery.

Conclusion We demonstrate that mouse iPS cells retain full potential for fetal liver development and describe procedures that facilitates the efficient generation of highly differentiated human hepatocyte-like cells from iPS cells in vitro.