高效制备昆明鼠胚胎成纤维细胞饲养层

背景：小鼠胚胎成纤维细胞作为饲养层是胚胎干细胞培养最常用的方法,能有效抑制胚胎干细胞分化并促进其增殖,但其制备过程繁琐,工作量大,准备周期长。 目的：探索建立小鼠胚胎成纤维细胞饲养层简单、高效的培养体系。 方法：取13.5 d胎龄胎鼠用改良组织块法及简化酶消化法分离培养原代成纤维细胞,倒置显微镜下观察不同方法培养的原代和传代鼠胚胎成纤维细胞的生长形态、结构及细胞数量变化。收集鼠胚胎成纤维细胞进行冻存,复苏后细胞经不同浓度作用时间的丝裂霉素C处理,制备饲养层。 结果与结论：两种简化方法培养的原代鼠胚胎成纤维细胞生长状态良好,得到高效优质足量细胞,操作过程简单,省去了多次消化、离心、细胞计数等繁琐操作,均适宜于鼠胚胎成纤维细胞的原代培养。简化复苏法复苏后的细胞,按其生长汇合情况,以丝裂霉素C 10 mg/L作用1.5~2.0 h或1 mg/L培养过夜,省时并可获得细胞生长状态最佳的饲养层。     

CF-1小鼠胚胎成纤维细胞饲养层的制备**

背景：小鼠胚胎成纤维细胞作为干细胞生长用饲养层,优于无饲养层,它能够分泌一些既促进干细胞生长又能抑制干细胞分化的因子。 目的：建立CF-1小鼠胚胎成纤维细胞饲养层最佳的分离培养方法,分析丝裂霉素C抑制成纤维细胞增殖的最佳浓度与时间,用于培养诱导多能性干细胞。 方法：取孕10~15 d CF-1小鼠,分离胎鼠原代成纤维细胞,经不同质量浓度(5,10,15,20 mg/L)丝裂霉素C处理不同时间(1,1.5,2,2.5,3 h)制备饲养层,并观察其增殖情况。将人诱导多潜能干细胞或胚胎干细胞在丝裂霉素C处理过的饲养层上培养,观察细胞集落生长情况。 结果与结论：制备CF-1小鼠胚胎成纤维细胞饲养层的最佳胎龄为13.0~14.0 d。丝裂霉素C抑制CF-1小鼠胚胎成纤维细胞增殖的最佳浓度及作用时间为10 mg/L,2.5 h,成纤维细胞饲养层可以维持5~7 d。诱导多能性干细胞与胚胎干细胞在经10 mg/L丝裂霉素C处理2.5 h后饲养层上能发育成典型的“鸟巢”状干细胞集落。 关键词：胚胎成纤维细胞;诱导多潜能分化干细胞;饲养层;丝裂霉素C;细胞集落 doi:10.3969/j.issn.1673-8225.2012.10.017     

昆明小鼠胚胎成纤维细胞分离培养及应用

目的探讨昆明小鼠胚胎成纤维细胞培养及应用。方法取昆明小鼠胚胎分离成纤维细胞,用丝裂霉素C处理成纤维细胞为胚胎干细胞制备饲养层,消化贴壁成纤维细胞为核移植提供供体细胞。结果13.5d、14.5d、15.5d孕鼠均可分离出成纤维细胞,14.5d孕鼠制作的成纤维细胞形态规则,3-5代成纤维细胞经处理可作饲养层,可作核移植供体细胞。结论昆明小鼠可分离成纤维细胞,用于饲养层制作及核移植供体细胞。     

胚胎干细胞饲养层培养的改良法

198 1年Martin[1] 等首次分离培养了小鼠的胚胎干细胞(embyonicstemcell)后 ,胚胎干细胞已成为当今生物医学最热门和最为前沿的研究课题之一 ,而饲养层细胞对于胚胎干细胞的增殖和维持未分化状态具有重要的作用。目前 ,多熟研究采用小鼠成纤维细胞作为饲养层 ,也有用人胚胎成纤维细胞做饲养层[2 ] 。用传统的方法制备饲养层 ,耗时较长 ,成纤维维细胞的质与量不稳定 ,为此 ,对原方法进行了改良 ,力求在较短时间内 ,培养出优质高产的小鼠成纤维细胞。1　材料和方法1 1　培养液和消化液　用DMEM的培养液 (Gibco公司 ) ,补加NaHCO32g/L及H…     

人胚胎成纤维细胞饲养层的制备

背景：极小胚胎样干细胞是近年来发现的一种具有类似胚胎干细胞生物学特性的非造血干细胞,但对其体外培养扩增的方法报道极少。有研究推测,人胚胎成纤维细胞能为人骨髓极小胚胎样干细胞体外培养扩增提供良好的微环境。 目的：从人胚胎躯干中分离、培养人胚胎成纤维细胞,制备人胚胎成纤维细胞饲养层用于人骨髓极小胚胎样干细胞的培养。 方法：利用胰酶消化法从孕5-9周龄人胚胎躯干中分离培养人胚胎成纤维细胞。制作饲养层,使用不同浓度丝裂霉素C处理后,用于培养分选后的人骨髓极小胚胎样干细胞,以细胞形态、生长曲线作为胚胎成纤维细胞和饲养层的评价指标。 结果与结论：从人胚胎中成功分离培养出人胚胎成纤维细胞,该细胞可传代24代以上,且经过传代及冻存复苏后生物学特性无改变。丝裂酶素C低于12 mg/L时,人胚胎成纤维细胞增殖不能完全抑制;高于14 mg/L,人胚胎成纤维细胞可能死亡。12 mg/L丝裂霉素C作用3 h后能较好地抑制人胚胎成纤维细胞的增殖,并且保持其活力约2周,可以在很长一段时间内用作人骨髓极小胚胎样干细胞的饲养层。     

制作诱导多能干细胞饲养层细胞最佳条件的研究

诱导多能干细胞(IPS)是近年来研究的热门,而IPS细胞体外培养需要饲养层细胞。小鼠胚胎成纤维细胞(MEF)可分泌白血病抑制因子,作为IPS细胞的饲养层细胞。目的建立分离培养小鼠胚胎成纤维细胞的体系,制作高质量的IPS饲养层细胞。方法选妊娠11.5~15.5d的昆明小鼠制作MEF细胞,选择第三代MEF细胞用不同浓度丝裂霉素C处理,制作饲养层细胞,在饲养层细胞上接种IPS细胞,观察各组IPS细胞生长状态并计算克隆数目。结果妊娠第13.5天的胚胎制作的MEF,经10μg/ml的丝裂霉素C处理3h的饲养层细胞状态较好,其IPS生长状况最好,克隆数目和质量最佳。结论不同胎龄胚胎分离的MEF可用做IPS饲养层,第13.5d的胚胎分离的MEF细胞经10μg/ml的丝裂霉素C处理3h制成的饲养层细胞最适于IPS细胞生长。     

人胚胎成纤维细胞与小鼠胚胎成纤维细胞生物学特性比较

探讨人胚胎成纤维细胞用于人胚胎干细咆体外长期培养的可行性，以含10％胎牛血清的DMEM(低糖)溶液为培养基，对人胚胎成纤维细胞的生长形态、对胰酶的敏感性、生长曲线及细胞周期进行研究，并与小鼠胚胎成纤维细胞作比较。结果显示，人胚胎成纤维细胞和小鼠胚胎成纤维细胞在体外均为贴壁生长型细胞，与小鼠胚胎成纤维细胞相比，人胚胎成纤维细胞生长更旺盛，且细胞寿命更长；在室温条件下，对0．25％胰酶更敏感，消化时间不宜超过3min。提示人胚胎成纤维细胞不仅在生长状况上与小鼠胚胎成纤维细胞类似，而且作为人胚胎干细胞体外长期培养的饲养层，在使用期限上优于后者，值得进一步研究。     

小鼠胚胎干细胞饲养层培养体系的优化筛选

目的：建立小鼠胚胎干细胞饲养层培养体系。方法：用5种不同鼠胚成纤维细胞为饲养层，进行小鼠胚胎干细胞的分离培养，观察5种饲养层培养体系对小鼠胚泡发育，内细胞团增殖及胚胎干细胞分离培养的作用。结果：原代或冻存复苏后的原代培养鼠胚成纤维细胞用于制备饲养层，有利于胚泡的贴壁，孵化，内细胞团增殖形成巢式生长集落，离散后培养，可以观察到胚胎干细胞集落的出现，并可在短期内维持胚胎干细胞的正常形态，不发生分化，与其他三组有明显差异。结论：原代或冻存复苏后的原代培养鼠胚成纤维细胞饲养层是用于胚胎干细胞分离培养的有效的培养体系。     

C57BL/6小鼠胚胎成纤维细胞生物学特性及饲养层制备

背景：昆明小鼠胚胎成纤维细胞是目前最常用的饲养层细胞,C57BL/6小鼠胚胎成纤维细胞作为饲养层的研究鲜有报道。目的：体外分离和培养C57BL/6小鼠胚胎成纤维细胞,制备饲养层,力求扩大小鼠胚胎成纤维细胞的来源。方法：用不同浓度胰蛋白酶分步消化法体外分离和培养C57BL/6小鼠胚胎成纤维细胞,观察其生物学特性,研究其生长规律,并制备小鼠胚胎成纤维细胞饲养层,检测干细胞在所制备饲养层上的生长状态。结果与结论：不同浓度胰蛋白酶分步消化法制备的C57BL/6小鼠胚胎成纤维细胞生长状态好,获得的成纤维细胞数量多,增殖活跃。在细胞冻存后1,2周、1,3,6个月内复苏的细胞存活率差异无显著性意义。C57BL/6小鼠胚胎成纤维细胞在第2-5代增殖旺盛,第6代以后细胞增殖出现明显下降。种植到培养皿上的C57BL/6小鼠饲养层细胞在种植后3 d内活力高,种植4 d以后细胞活力急剧下降。所以C57BL/6小鼠胚胎成纤维细胞来源的饲养层的最佳使用时间为灭活后3 d内,C57BL/6小鼠胚胎成纤维细胞饲养层和昆明小鼠胚胎成纤维细胞饲养层一样,能很好地支持胚胎干细胞及诱导多能干细胞生长。 中国组织工程研究杂志出版内容重点：组织构建;骨细胞;软骨细胞;细胞培养;成纤维细胞;血管内皮细胞;骨质疏松;组织工程全文链接：     

人胚胎干细胞饲养层的制备及生物学活性

背景：建立一种既可以大量制备,又能保存并保持较高活性的饲养层是胚胎干细胞培养研究不可缺少的环节。 目的：体外分离培养、冻存复苏ICR小鼠胚胎成纤维细胞,观察其生物学特性。 方法：取ICR小鼠13.5 d胚胎,用胰蛋白酶分步消化法分离培养小鼠成纤维细胞,对冻存复苏后的小鼠胚胎成纤维细胞形态、生长曲线、贴壁率、细胞化学染色及支持人胚胎干细胞生长特性等进行观察。 结果与结论：复苏后的小鼠胚胎成纤维细胞在体外传代30 min时80%以上细胞贴壁,生长曲线显示细胞增殖活跃,细胞化学染色AKP、PAS、POX阴性,能长期支持人胚胎干细胞传代生长。提示此方法所获得的小鼠胚胎成纤维细胞复苏后有较高的生物学活性,可为人胚胎干细胞扩增提供稳定、优质的饲养层细胞。     

饲养层细胞体系及白血病抑制因子对维持小鼠胚胎干细胞未分化状态的作用

目的建立并筛选最适合的小鼠胚胎干(ES)细胞饲养层培养体系。方法建立7种经过不同处理的鼠胚成纤维细胞作为饲养层培养体系,分别进行小鼠胚胎干细胞的培养,观察7种饲养层培养体系对小鼠ES细胞增殖能力及未分化状态的维持情况。结果小鼠胚胎细胞在3代内均可用于ES细胞的培养。与其他各组比较,第3代培养鼠胚成纤维细胞经丝裂霉素C处理2h后加外源白血病抑制因子(IF,10μg/ml)用作饲养层的克隆形成率和碱性磷酸酶(AKP)染色阳性度最高。结论外源性白血病抑制因子是抑制小鼠ES细胞分化的主要因素。     

BLBP-Immunoreactive Cells in the Primary Culture of Neural Precursors from Embryonic Mouse Brain

The population of neurosphere cells was studied by staining for the radial glial marker BLBP protein. An immunohistochemical study of cultures showed that neurosphere cells proliferate and retain the ability for pluripotent differentiation over 9 passages. BLBPimmunoreactive cells were present in neurospheres at all passages. However, they did not belong to the population of proliferating multipotent precursors or GFAP-positive cells. BLPB expression was detected in S-100b-positive cells of astrocyte differentiation. Our results suggest that BLBP-immunopositive cells of the radial glia in vitro loss the state of multipotent precursors and differentiate into the astroglia. Otherwise, some heterogeneous cells of the radial glia include a previously unknown linear population that differentiates into S-100b-positive astrocytes. Translated from Kletochnye Tekhnologii v Biologii i Meditsine, No. 1, pp. 16-22, 2009     

小鼠Kupffer细胞分离及细胞培养

目的 采用在体胶原酶灌注、不连续密度梯度离心、选择性贴壁3步法分离Kupffer细胞(Kupffer cells,KCs),探讨其在分离小鼠KCs的应用及其对KCs生物活性的影响.方法 根据原位灌注和梯度离心方法不同随机分为4组:无胶原酶原位灌注+3层梯度离心组(A)、无胶原酶原位灌注+双层梯度离心组(B)、胶原酶原位...     

胚体培养对小鼠ES细胞定向神经分化的影响研究

为了研究胚胎干细胞（ES细胞）的定向诱导分化过程中胚体的形成对其后分化的影响，通过悬滴培养、悬浮培养及两者结合的方法得到2～4d的胚体（EBs），利用全反视黄酸（RA）对其处理4d后，进行免疫细胞化学和兴奋性功能的检测，观察比较了不同培养方式和不同培养时间下EBs分化出来的神经细胞所占的比例。结果表明，用单纯悬浮3d或悬滴3d转悬浮1d的培养方法得到的胚体其神经分化的比例较高，这对进一步阐明胚胎干细胞自身内部调控诱导分化的机制有一定的参考意义。     

Self Renewal of Embryonic Stem Cells in the Absence of Feeder Cells and Exogenous Leukaemia Inhibitory Factor

Abstract

To evaluate the role of leukaemia inhibitory factor (LIF) for maintaining pluripotent embryonic stem (ES) cells in culture, we established several exogenous LIF-independent ES cell lines by continuous passaging in culture. The newly established ES cells, Kli and CBli, sustained their growth and remained undifferentiated in LIF-deficient medium. Analysis of chimaeric animals, produced with the p-galactosidase transgenic Kli ES cells, revealed that LDF-independent ES cells can contribute to all embryonic germ layers. There was no detectable LIF protein in ES cell conditioned medium, and no upregulation of LIF mRNA was found. The addition of neutralising anti-LIF antibodies was not sufficient to abrogate the self renewal of the Kli ES cells. These studies suggest that the signalling pathway involving diffusible LIF can be bypassed for maintaining the pluripotency in culture, and indicate a considerable heterogeneity in growth factor dependence and differentiation of different ES cells.     

Efficient and User-Friendly Pluripotin-based Derivation of Mouse Embryonic Stem Cells

Classic derivation of mouse embryonic stem (ES) cells from blastocysts is inefficient, strain-dependent, and requires expert skills. Over recent years, several major improvements have greatly increased the success rate for deriving mouse ES cell lines. The first improvement was the establishment of a user-friendly and reproducible medium-alternating protocol that allows isolation of ES cells from C57BL/6 transgenic mice with efficiencies of up to 75%. A recent report describes the use of this protocol in combination with leukemia inhibitory factor and pluripotin treatment, which made it possible to obtain ES cells from F1 strains with high efficiency. We report modifications of these protocols for user-friendly and reproducible derivation of mouse ES cells with efficiencies of up to 100%. Our protocol involves a long initial incubation of primary outgrowths from blastocysts with pluripotin, which results in the formation of large spherical outgrowths. These outgrowths are morphologically distinct from classical inner cell mass (ICM) outgrowths and can be easily picked and trypsinized. Pluripotin was omitted after the first trypsinization because we found that it blocks attachment of ES cells to the feeder layer and its removal facilitated formation of ES cell colonies. The newly established ES cells exhibited normal karyotypes and generated chimeras. In summary, our user-friendly modified protocol allows formation of large spherical ICM outgrowths in a robust and reliable manner. These outgrowths gave rise to ES cell lines with success rates of up to 100%.     

Evidence of Extracellular Vesicles Biogenesis and Release in Mouse Embryonic Stem Cells

Extracellular vesicles (EVs) released by mouse embryonic stem cells (mESCs) are considered a source of bioactive molecules that modulate their microenvironment by acting on intercellular communication. Either intracellular endosomal machinery or their derived EVs have been considered a relevant system of signal circuits processing. Herein, we show that these features are found in mESCs. Ultrastructural analysis revealed structures and organelles of the endosomal system such as coated pits and endocytosis-related vesicles, prominent rough endoplasmic reticulum and Golgi apparatus, and multivesicular bodies (MVBs) containing either few or many intraluminal vesicles (ILVs) that could be released as exosomes to extracellular milieu. Besides, budding vesicles shed from the plasma membrane to the extracellular space is suggestive of microvesicle biogenesis in mESCs. mESCs and mouse blastocyst express specific markers of the Endosomal Sorting Complex Required for Transport (ESCRT) system. Ultrastructural analysis and Nanoparticle Tracking Analysis (NTA) of isolated EVs revealed a heterogeneous population of exosomes and microvesicles released by mESCs. These vesicles contain Wnt10b and the Notch ligand Delta-like 4 (DLL4) and also the co-chaperone stress inducible protein 1 (STI1) and its partner Hsp90. Wnt10b and Dll4 colocalize with EVs biogenesis markers in mESCs. Overall, the present study supports the function of the mESCs endocytic network and their EVs as players in stem cell biology.