昆明系小鼠胚胎干细胞分离培养的优化

以昆明系小鼠为对象,经过丝裂霉C处理成纤维细胞(Mouse embryonic fibroblast,MEF)制备饲养层,对影响小鼠胚胎干细胞(Embryonic stem cell,ES细胞)分离培养的相关因素进行研究。分别收集小鼠3.5d的囊胚(扩张囊胚)和4.5d囊胚(孵化囊胚)进行培养,比较扩张囊胚和孵化囊胚的贴壁率、原代克隆率及传代率的情况。收集3.5d胚龄的囊胚,通过全胚法和免疫外科法对内细胞团(Inner cell mass,ICM)进行分离培养ICM集落,确定离散ICM的适宜时间。用0.25%胰酶+0.04%EDTA,0.125%胰酶+0.02%EDTA和0.25%胰酶+1%小鸡血清等方法对小鼠ES细胞集落进行传代,观察不同酶浓度对ES细胞分离克隆的影响。结果显示,孵化囊胚的贴壁率高于扩张囊胚(P0.05),但传代率则相反(P0.05),原代克隆率差异不显著(P0.05);一般ICM增殖培养2～3d(免疫外科法)或4～5d(全胚培养法)后,出现典型的克隆集落,再挑取ICM;0.125%胰酶+0.02%EDTA及0.25%胰酶+1%小鸡血清,形成ES原代克隆率较高,2组没有显著性差异(P0.05);结果表明,分离得到的ES细胞经形态学观察,AKP染色,体外分化试验等表明其具有胚胎干细胞的特性。     

ICR小鼠胚胎干细胞的分离与培养

为了研究不同条件对ICR小鼠ES细胞的影响,试验以12.5～13.5 dICR小鼠胚胎成纤维细胞(MEF)为饲养层,以3.5 d ICR小鼠胚胎为试验材料,探讨了血清、生长因子及传代方法对ICR小鼠ES细胞分离培养的影响.结果表明:采用含15%FBS的ES细胞培养液的囊胚贴壁率及ICM增殖率(79.3%,69.0%)均...     

ICR小鼠胚胎干细胞的分离与培养

为了研究不同条件对ICR小鼠ES细胞的影响,试验以12.5~13.5 d ICR小鼠胚胎成纤维细胞(MEF)为饲养层,以3.5 d ICR小鼠胚胎为试验材料,探讨了血清、生长因子及传代方法对ICR小鼠ES细胞分离培养的影响。结果表明:采用含15%FBS的ES细胞培养液的囊胚贴壁率及ICM增殖率(79.3%,69.0%)均比含15%KSR、5%FBS+10%KSR的细胞培养液高(42.9%,28.6%;75.0%,54.2%),ES细胞最高传至6代;培养液中添加10 ng/mL LIF+10 ng/mL SCF的效果比单独添加1种因子的效果好,最高传至6代,高于单独添加1种因子的传代数(4代,2代);用3种传代方法进行传代时,采用差异贴壁法传代效果最佳,最高传至8代,酶消化法传至4代,机械加酶消化法传至6代。     

昆明白小鼠胚胎生殖细胞的分离与培养

以昆明白品系小鼠胎儿生殖嵴为材料，以不同的培养液分离培养胚胎生殖细胞（EG cells），发现小鼠胎儿肝细胞条件培养液的效果好于未添加白血病抑制因子（LIF）的基础培养液，而差于添加了1000IU／mL LIF的基础培养液。同时，试验对比了从不同胎龄胎儿分离培养原始生殖细胞（PGCs）的情况，鉴定了EG细胞的生物学特性；EG细胞经体外培养，可以分化为神经样细胞、上皮样细胞和简单类胚体。     

影响昆明小鼠和BALB/c小鼠胚胎干细胞分离、克隆、传代的若干因素

对昆明小鼠和BALB／c小鼠2种胚胎的研究表明，2种品系小鼠胚胎均可用作胚胎干细胞（ES）分离建系的材料，两者在ES分离、传代上无显著差异（P〉0．05）；大鼠心肌细胞条件培养液与添加LIF的ES常规培养液相比，显著提高了小鼠ES细胞F1、F2出现率（P〈0．05）；采用低浓度消化液使形成ES克隆的比率分别从14％、16％提高到35％、32％，使ES传到第5代的比率分别从1．7％、0提高到5％、7．1％；而采用连续消化法使形成ES克隆的比率从15％、17％提高到40％、50％，使ES传到第5代的比率从0、1％提高到10％、20％；对ES进行伊红染色、核型分析、AKP染色及体外分化能力检测，证实所分离的ES符合小鼠ES的一系列特征。     

小鼠胚胎干细胞培养、克隆、分离、传代研究

对影响小鼠胚胎干细胞（Embryonic stem cells,ES细胞）培养、克隆、分离、传代效果的因素进行了探索研究。应用223枚昆明白小鼠胚胎和20枚129品系小鼠胚胎的研究结果表明，129品系小鼠胚胎比昆明白小鼠胚胎更适合作为ES细胞建系的材料，两者FS出现率差异显著（P＜0．05）；以DMEM＋10％NBS＋10％FCS为基础培养液，分别加入LIF、胰岛素、LIF＋SCF，极显著提高昆明白小鼠胚胎贴壁率，ICM生长率及F1、F2出现率（P＜0．01），而在DMEM＋10％NBS＋10％FCS＋LIF＋SCF为培养液，得到昆明白小鼠胚胎最高贴壁率、ICM生长率及传代率；4dpc胚胎传代情况显著好于3．5dpc胚胎（P＜0．05）。     

胚胎干细胞分离培养研究进展

胚胎干细胞(ESCs)是一种高度未分化,能自我复制、自我更新,在体外连续传代并保持未分化状态和具有发育全能性的细胞.文章从研究概况、体外分离培养、生物学特性、鉴定方法、影响ESCs分离培养的因素、存在问题以及应用前景等方面对胚胎干细胞进行了概述.     

昆明小鼠胚胎干细胞培养体系的优化

为了更高效地分离昆明小鼠胚胎干细胞,本研究从饲养层、胚胎发育阶段和培养液方面进行优化。将3代以内的小鼠胎儿成纤维细胞(MEF)用丝裂霉素C处理后,分别按1×104、1×105、1×106·mL-1密度接种,以H-DMEM+15%KSR+LIF为培养液,观察不同密度饲养层对昆明小鼠胚胎干细胞(ES细胞)生长的影响,并研究胚胎发育阶段和培养液中分别添加干细胞生长因子(SCF)、SCF+胰岛素对昆明小鼠ES细胞分离克隆的影响。结果显示,胚胎在密度为1×105·mL-1的饲养层上,F1代和F2代ES细胞克隆形成率均显著高于其他2组(P<0.05)。囊胚的F2代ES细胞克隆形成率显著高于桑椹胚(P<0.05),培养液中添加SCF显著提高昆明小鼠胚胎贴壁率(P<0.05),同时添加SCF和胰岛素得到昆明小鼠最高胚胎贴壁率及F1、F2代ES细胞克隆形成率。所分离的ES细胞显示AKP染色强阳性,Oct-4、SSEA-1的免疫荧光检测阳性,具有ES细胞的特点。由此认为,发育至囊胚的胚胎在MEF密度为1×105·mL-1上,培养液中同时添加SCF和胰岛素更适合昆明小鼠ES细胞的分离培养。     

某些因素对牛和小鼠类胚胎干细胞分离与培养的影响

以荷斯坦牛胚胎和小鼠胚胎为材料 ,研究了犊牛血清、饲养层、培养液、添加物和消化液对牛胚胎干细胞和小鼠胚胎干细胞克隆效率的影响。结果表明 ,在 2 4h内使小鼠胚胎贴壁率达 86 %以上的犊牛血清可用于小鼠和牛胚胎干细胞的分离 ;在 ES细胞分离与克隆中 ,以 15 %～ 2 0 %犊牛血清为宜 ,在 DMEM(L)培养基中添加 0 .1μmol/LNa2 Se O3 0 .1mmol/Lβ-巯基乙醇 10 μg/L IGF 10 0 0 IU/m L L IF,能显著提高牛 ES细胞分离与克隆效率 ;在TCM199、DMEM(高糖 )和 DMEM(低糖 ) 3种培养基中 ,低糖 DMEM更适宜于牛 ES细胞的分离 ;优秀胚胎形成的团状 ICM更适宜于分离与克隆 ES细胞 ,在 37℃用低浓度消化液处理 ICM或 ES细胞集落 ,再以机械将其离散为细胞小块 ,ES细胞克隆效率最高。     

美国用小鼠胚胎干细胞培养小鼠精子试验的介绍

《福建畜牧兽医》杂志2004年2期刊登了介绍美国科学家用小鼠的胚胎干细胞培养卵子研究的文章。其中谈到2003年6月，科学家还用胚胎干细胞培养小鼠精子的试验。为了让读者能了解这一胚胎干细胞培养技术。本文简要介绍这一项研究成果。     

温度对体外培养小鼠精原干细胞的影响

将分离纯化的小鼠精原干细胞分别置于37、34、30℃及50％CO2、饱和湿度条件下进行体外培养。结果表明，3种温度下的精原干细胞均可以存活并增殖，但随着体外培养时间的延长，细胞的生长状态、增殖数量和存活时间有明显差异。34℃下细胞平均存活时间最长，增殖数量最多。统计分析显示，34℃与30、37℃下细胞平均存活时间有显著差异（P＜0．05），表明34℃是小鼠精原干细胞较为适宜的生长环境。     

绵羊类胚胎干细胞的分离与克隆

从胚胎发育阶段、饲养层和培养体系等方面对影响绵羊类ES细胞分离、克隆效率的因素进行探讨。结果显示：致密桑葚胚和囊胚的ICM增殖率高于囊胚和孵化囊胚。绵羊类ES细胞在同源绵羊胎儿成纤维细胞（SEF）上生长比较缓慢,最终传代次数也低于小鼠胎儿成纤维细胞（MEF）组。培养液中同时添加胎牛血清（FBS）和Knock-out血清替代品（KSR）,绵羊类ES传至7代,添加了碱性成纤维细胞生长因子（bFGF）后,最高可传至8代,而单纯添加KSR或FBS,分别传至4代和5代。对类ES细胞进行AKP染色、核型分析、体外分化试验,证实分离的类ES细胞符合ES细胞的主要特征,而且表达多潜能性细胞因子Nanog。由此认为,致密桑葚胚和囊胚更适合绵羊类ES细胞的体外分离和培养,而且MEF更适合于绵羊类ES细胞的分离传代,培养液中添加5%FBS和15%KSR,比较适合类ES细胞的分离传代,bFGF对绵羊类ES细胞的增殖具有促进作用。     

Evaluation of embryonic age and the effects of different proteases on the isolation and primary culture of chicken intestinal epithelial cells in vitro

The present study evaluates the effects of embryonic age and proteolytic enzymes on the isolation and primary culture of chicken enterocyte and to establish an effective technique for chicken intestinal epithelial cell (IEC) cultivation. Fourteen‐day‐old, 16‐day‐old and 18‐day‐old embryos (average weight: 52.23 ± 0.76 g, 50.86 ± 0.99 g, 48.98 ± 1.03 g) were the source for preparation of enterocyte culture, and trypsin‐ethylene diamine tetraacetic acid, collagenase, thermolysin and combination of collagenase and thermolysin were used for digestion medium. Optimal culture protocols were determined by qualitative assays of proliferation. Cells isolated by using 14‐day‐old embryo and collagenase obtain the best attachment and growth in culture, and the production of continuously growing IEC cultures. Thus, we conclude that the use of collagenase as a dissociating enzyme and 14‐day‐old embryo as a source can be advantageously applied to the isolation of chicken IEC and this method may be useful for various applications and basic studies of the intestinal tract concerning such objects as physiology, immunology and toxicology.     

昆明小鼠胚胎成纤维细胞体外培养条件初步研究

本研究旨在探索影响小鼠胚胎成纤维细胞(mouse embryonic fibroblast,MEF)分离培养的因素,建立有效的胚胎成纤维细胞培养体系,为构建饲养层细胞与体细胞核移植技术的细胞核供体建立平台。本研究用组织细胞培养液DMEM作为基础培养液,观察了不同胎龄、不同血清浓度及不同胰蛋白酶作用时间等因素对MEF分离培养的影响。结果显示,在所进行的4个胎龄8.5、10.5、12.5、14.5 d的比较试验中,原代成纤维细胞分离培养的最适胎龄为12.5 d,细胞贴壁迅速,12 h已完全贴壁,增殖速度快;在所进行的不同时间5、10、15、30 min的胰蛋白酶消化中,最佳时间为5~10 min;在所进行的5个血清浓度7%、9%、10%、11%、13%的比较试验中,添加11%胎牛血清浓度培养效果最佳,从3~5代增殖倍数稳定在1.35左右,传代时间也相对较长。以上结果表明,采用12.5 d胎鼠,胰蛋白酶消化5~10 min,在含有11%血清的DMEM培养液中培养MEF细胞时,原代和传代效果最好,传代至第3~5代时细胞生长增殖最旺盛,处于对数分裂期,适宜作为饲养层细胞与体细胞核移植细胞核供体。     

不同方法从小鼠胚胎干细胞分化拟胚体

建立简便有效的胚胎干细胞体外分化研究中制备拟胚体的方法。本实验以3种方法形成拟胚体：滋养层过生长法、悬浮法和胶原酶处理法,并与传统的悬滴法进行了比较。在不同的分化培养体系中以最终分化出搏动的心肌细胞评价形成有分化发育能力的拟胚体的效率。以RT—PCR检测了拟胚体和心肌细胞形成中基因的表达。结果表明,4种方法分化出搏动心肌细胞的比例不同。滋养层过生长法形成拟胚体的比例接近悬滴法．而悬浮法和胶原酶处理形成拟胚体的比例显著低于滋养层过生长法和悬滴法。形态学研究显示,拟胚体发育经历了简单拟胚体阶段到囊状拟胚体或成熟拟胚体。在拟胚体成熟过程中特异性胚层分化发育分子标记HNF-4、Bmp-4与Otx-2表达上调,与心肌细胞分化相关的基因α—MHC、β-MHC、GATA-4及Nkx2．5同样表达上调。表明不同途径可获得不同比例的有发育能力的拟胚体,在体外分化研究中滋养层过生长法则是简便有效的获得正常发育拟胚体的方法。     

Toxic effects of methylmercury,arsanilic acid and danofloxacin on the differentiation of mouse embryonic stem cells into neural cells

This study was performed to assess the neurotoxic effects of methylmercury, arsanilic acid and danofloxacin by quantification of neural-specific proteins in vitro. Quantitation of the protein markers during 14 days of differentiation indicated that the mouse ESCs were completely differentiated into neural cells by Day 8. The cells were treated with non-cytotoxic concentrations of three chemicals during differentiation. Low levels of exposure to methylmercury decreased the expression of GABA_A-R and Nestin during the differentiating stage, and Nestin during the differentiated stage. In contrast, GFAP, Tuj1, and MAP2 expression was affected only by relatively high doses during both stages. Arsanilic acid affected the levels of GABA_A-R and GFAP during the differentiated stage while the changes of Nestin and Tuj1 were greater during the differentiating stage. For the neural markers (except Nestin) expressed during both stages, danofloxacin affected protein levels at lower concentrations in the differentiated stage than the differentiating stage. Acetylcholinesterase activity was inhibited by relatively low concentrations of methylmercury and arsanilic acid during the differentiating stage while this activity was inhibited only by more than 40 µM of danofloxacin in the differentiated stage. Our results provide useful information about the different toxicities of chemicals and the impact on neural development.     

Enhancing effects of serum-rich and cytokine-supplemented culture conditions on developing blastocysts and deriving porcine parthenogenetic embryonic stem cells

The present study was conducted to develop an effective method for establishment of porcine parthenogenetic embryonic stem cells (ppESCs) from parthenogenetically activated oocyte-derived blastocysts. The addition of 10% fetal bovine serum (FBS) to the medium on the 3rd day of oocyte culturing improved the development of blastocysts, attachment of inner cell masses (ICMs) onto feeder cells, and formation of primitive ppESC colonies. ICM attachment was further enhanced by basic fibroblast growth factor, stem cell factor, and leukemia inhibitory factor. From these attached ICMs, seven ppESC lines were established. ppESC pluripotency was verified by strong enzymatic alkaline phosphatase activity and the expression of pluripotent markers OCT3/4, Nanog, and SSEA4. Moreover, the ppESCs were induced to form an embryoid body and teratoma. Differentiation into three germ layers (ectoderm, mesoderm, and endoderm) was confirmed by the expression of specific markers for the layers and histological analysis. In conclusion, data from the present study suggested that our modified culture conditions using FBS and cytokines are highly useful for improving the generation of pluripotent ppESCs.