共查询到19条相似文献，搜索用时 296 毫秒
1.
胚胎干细胞体外诱导分化的研究进展 总被引：2，自引：0，他引：2
胚胎干细胞(embryonic stem cell，ES细胞)是由早期胚胎内细胞团(ICM)或原始生殖(PGC)细胞经体外分离、抑制分化培养获得的多潜能细胞。ES细胞具有发育分化的多潜能性和无限的自我更新能力，能在体外长期培养并具有向机体各种组织细胞分化的潜能。由于ES细胞的全能性，在体外可以分化出包括3个胚层在内的所有细胞， 相似文献
2.
《河南畜牧兽医(综合版)》2014,(5):14-17
胚胎干细胞（ES细胞）是从早期胚胎内细胞团（ICM）或原始生殖细胞（PGCs）经体外分化抑制培养分离克隆的,ES细胞在动物克隆、转基因动物生产、细胞工程、组织工程、临床克隆治疗和发育生物学等的研究应用中起着重要的作用.为此,介绍胚胎干细胞的生物学特性,国内外研究进展和研究动态,阐明建立ES细胞系的技术要点以及ES细胞的应用及发展前景. 相似文献
3.
《畜牧兽医学报》2015,(10)
旨在为小鼠和猪多能性干细胞嵌合体制作提供参考,探讨胚胎干细胞(Embryonic stem cells或Embryonic germ cells,ES/EG)显微注射及受体胚胎发育时期等对胚胎发育的影响。对小鼠ES细胞和猪EG细胞分别进行研究:(1)将小鼠ES细胞分别注入小鼠桑椹胚和囊胚,比较不同发育时期受体胚胎体外培养的发育率和孵化率,以及注射胚胎和未注射胚胎体外培养的发育率和孵化率。结果表明,显微注射后的桑椹胚体外培养发育率和孵化率分别为94.7%和70.2%,囊胚率分别为84.6%和80.8%,注射后桑椹胚体外培养发育率极显著高于囊胚(P0.01),但注射后囊胚体外培养孵化率极显著高于桑椹胚(P0.01);未注射胚胎(注射胚胎)的体外培养发育率和孵化率分别为96.6%(89.9%)和67.8%(75.2%),未注射胚胎发育率极显著高于注射胚胎(P0.01),但注射胚胎孵化率极显著高于未注射胚胎(P0.01)。(2)将猪EG细胞分别注入猪桑椹胚、早囊、囊胚及孵化囊胚,比较不同发育时期受体胚胎移植后妊娠率以及注射胚胎和未注射胚胎体外培养的孵化率,并对猪EG细胞显微注射针和固定针的规格进行了探讨。结果表明,显微注射的桑椹胚、早囊及囊胚移植后妊娠率为67%,而显微注射的孵化囊胚移植妊娠率为0,桑椹胚、早囊及囊胚移植后受体母猪妊娠率极显著高于孵化囊胚(P0.01),由桑椹胚、早囊及囊胚注射后移植获得了两头嵌合体仔猪;显微注射和未显微注射的猪胚胎其孵化率分别为47.54%和72.97%,未注射胚胎孵化率极显著高于注射胚胎(P0.01)。确定猪EG嵌合体制作过程中,注射针外径约为30μm,内径约为25μm;固定针外直径约为130~150μm,内径约为40μm。嵌合体制作时,胚龄宜早不宜迟,桑椹胚显微注射更易操作,而且导入的时期较早,ES/EG细胞在嵌合体组织中可以有很高的贡献率,故选择桑椹胚进行注射。在本试验条件下,显微注射对小鼠胚胎发育影响不大,对猪胚胎影响较大,说明猪胚胎显微注射条件需要进一步优化。 相似文献
4.
胚胎干细胞（Embryonic stem cell,ES细胞）是从早期哺乳类动物胚胎或原始生殖细胞分离的具有全能性的细胞系。在体外分化抑制培养条件下,具有保持未分化的状态及无限增殖的能力。自Evans和Kaufman首次建立小鼠ES细胞系以来,各种动物ES细胞分离与克隆成为国际生物科学领域的热点课题之一。ES细胞可广泛应用于嵌合体的制备和克隆动物的生产。利用ES细胞遗传操作,可生产转基因动物,进行细胞基因结构与功能的关系以及细胞分化机制的研究。本研究采用不同培养方式对昆明小鼠类ES细胞进行分离及培养,供相关研究者参考。 相似文献
5.
5嵌合体鸡的生产 嵌合体制作最早主要用于发育生物学、细胞遗传学等学科的理论研究。目前，禽类嵌合体的制作中作供体细胞用的囊胚层细胞(BC)和原生殖细胞(PGCs)可以代替受精卵和早期胚胎用于体外遗传操作，已成为禽类转基因研究的一个热点。同时，BC和PGCs还可以在体外进行培养和冷冻保存。基本原理是经过遗传操作的BC细胞或PGCs细胞作供体，嵌合到受体胚胎中。如果是嵌合在生殖细胞，则该嵌合体性成熟后可产生一定比例经过遗传操作的配子。 有关鸡嵌合体方面的报道及鸡嵌合体制作方法、嵌合体的嵌合程度的判断以及怎样提高嵌… 相似文献
6.
胚胎干细胞分离和克隆影响因素的研究进展 总被引：1，自引：0，他引：1
胚胎干细胞ES是从早期胚胎或原始生殖细胞中分离出来的能够在体外进行传代培养,而不分化的全能性细胞,ES细胞最主要的生物学特征是具有发育的全能性或多能性,ES细胞能在体外培养、增殖、传代、冻存和诱导分化,是研究生物发育、行为和建立人体疾病模型的理想工具,本文重点论述了影响胚胎干细胞分离和克隆的因素。并展望了胚胎干细胞的应用前景。 相似文献
7.
鸡胚胎干细胞是一种多能性干细胞,从X期胚盘分离胚盘细胞或早期鸡胚的生殖嵴分离原始生殖细胞,经体外长期抑制分化培养可得到鸡胚胎干细胞。为维持细胞在培养过程中的未分化状态,需要采用饲养层细胞培养,同时设计合理的培养液配方并添加多种抑制分化或促进增殖的细胞因子。通过碱性磷酸酶活性检测、胚胎表面特异性抗原检测、分化试验及嵌合体试验等方法,可对鸡胚胎干细胞进行准确鉴定。文章主要就鸡胚胎干细胞的分离、培养与鉴定方法的研究进展及其应用前景进行简要综述,为进一步发展更高效的鸡胚胎干细胞培养体系并应用于生产实践提供一定的借鉴。 相似文献
8.
9.
胚胎干细胞 (ES细胞 )是由哺乳动物早期胚胎分离克隆的一类未分化二倍体细胞 ,能在体外增殖 ,又能保持未分化状态。在一定条件下 ,ES细胞可向多个方向分化 ,并生成多种功能细胞。ES细胞在遗传上具有可操作性 ,即导入外源基因、标志基因和报告基因 ,诱导基因突变 ,基因打靶或导入额外原有基因使之过度表达等。利用该特性可制作各种实验模型并进行各种基因分析。ES细胞能被诱导分化为构成机体的任一种细胞类型 ,可用于临床细胞、组织和器官的修复和移植治疗 ,研究ES细胞的定向分化有着重要的理论和应用价值。1 ES细胞分化机制研究现状目… 相似文献
10.
胚胎干细胞的体外培养及应用 总被引：1，自引：0，他引：1
来自着床前的囊胚和早期胚胎的胚胎干细胞(ES细胞)是一类具有发育多能性和全能性的细胞。它在生命科学的各个领域产生非同凡响的影响。文中就ES细胞的体外培养，诱导分化及其在畜牧业、生命科学的基础学科研究和医学领域的应用简要综述。 相似文献
11.
Hiroshi Kagami 《Animal Science Journal》2016,87(9):1065-1075
Stem cells have prulipotency to differentiate into many types of cell lineages. Recent progress of avian biotechnology enabled us to analyze the developmental fate of the stem cells: embryonic stem cells / primordial germ cells (PGCs). The stem cells were identified in the central area of the area pellucida of the stage X blastoderms. These cells could be applied for production of germline chimeras and organ regeneration. Generation of medical substrate in transgenic chickens has considerable interests in pharmaceuticals. Sex alteration of the offspring should be enormously beneficial to the poultry industry. Fertilization of the sex‐reversed sperm could lead to sexual alteration of the offspring. These strategies using stem cells / PGCs should be one of the most powerful tools for future poultry breeding. 相似文献
12.
Isolation and culture of rabbit primordial germ cells 总被引：2，自引：0，他引：2
Kakegawa R Teramura T Takehara T Anzai M Mitani T Matsumoto K Saeki K Sagawa N Fukuda K Hosoi Y 《The Journal of reproduction and development》2008,54(5):352-357
Primordial germ cells (PGCs) are embryonic precursors of the gametes of adult animals and are considered stem cells of the germline. Since their proliferation in vitro correlates well with the schedule of developmental changes in vivo, they might be interesting research tools for genomic imprinting, germ-cell tumors and fertility. Furthermore, once primordial germ cells are separated and placed on a feeder layer with cytokines, they become cultured pluripotent cell lines called embryonic germ (EG) cells. EG cells share several important characteristics with embryonic stem (ES) cells as they can also contribute to the germ line of chimeras. To investigate the characteristics of PGCs and establish rabbit EG (rEG) cells, we cultured rabbit PGCs (rPGCs) in vitro with various combinations of leukemia inhibitory factor (LIF), basic fibroblast growth factor (bFGF) and forskolin on inactivated mouse embryonic fibroblast (MEF) feeder layers. The present study found PGC proliferation in early cultures and induction of rEG-like colonies. These cells expressed pluripotent markers, such as alkaline phosphatase activity, OCT-4, Sox-2 and SSEA-1, in the undifferentiated state; however, the cells did not develop into a teratoma when injected into the kidney capsules of SCID mice, although the restricted differentiation potentials to neural cells were determined via embryoid body formation. From these characteristics and further characterization of the germ stem cell markers Vasa, SCP-1 and SCP-3, we suggested that these were hybrid cells with characteristics somewhere between PGC and EG cells. 相似文献
13.
Nakamura Y Usui F Miyahara D Mori T Ono T Kagami H Takeda K Nirasawa K Tagami T 《The Journal of reproduction and development》2012,58(4):432-437
Primordial germ cells (PGCs) are embryonic precursors of germline cells with potential applications in genetic conservation, transgenic animal production and germline stem cell research. These lines of research would benefit from improved germline transmission of transplanted PGCs in chimeric chickens. We therefore evaluated the effects of pretransplant X-irradiation of recipient embryos on the efficacy of germline transmission of donor PGCs in chimeric chickens. Intact chicken eggs were exposed to X-ray doses of 3, 6 and 9 Gy (dose rate = 0.12 Gy/min) after 52 h of incubation. There was no significant difference in hatching rate between the 3-Gy-irradiated group and the nonirradiated control group (40.0 vs. 69.6%), but the hatching rate in the 6-Gy-irradiated group (28.6%) was significantly lower than in the control group (P<0.05). No embryos irradiated with 9 Gy of X-rays survived to hatching. X-irradiation significantly reduced the number of endogenous PGCs in the embryonic gonads at stage 27 in a dose-dependent manner compared with nonirradiated controls. The numbers of endogenous PGCs in the 3-, 6- and 9-Gy-irradiated groups were 21.0, 9.6 and 4.6% of the nonirradiated control numbers, respectively. Sets of 100 donor PGCs were subsequently transferred intravascularly into embryos irradiated with 3 Gy X-rays and nonirradiated control embryos. Genetic cross-test analysis revealed that the germline transmission rate in the 3-Gy-irradiated group was significantly higher than in the control group (27.5 vs. 5.6%; P<0.05). In conclusion, X-irradiation reduced the number of endogenous PGCs and increased the germline transmission of transferred PGCs in chimeric chickens. 相似文献
14.
囊胚注射转基因ES细胞制作嵌合体的研究 总被引：2，自引：0，他引：2
在小鼠胚胎成纤维细胞制作的饲养层上培养并成功的维持了携带LacZ基因的胚胎干细胞系（S8），在此基础上，以S8为供体细胞，以远交系昆明白小鼠3．5d胚胎为受体，通过显微注射法将供体细胞转移到受体的囊胚腔内，经过恢复培养，移植到代孕鼠昆明白雌鼠的子宫中；后代在嵌合体出生一周后进行判定。本试验用8～13代的S8细胞共注射胚胎597枚，经1～3h恢复培养，有585枚胚胎重新具有膨大的囊胚腔，细胞轮廓分明，滋养层细胞间连接也清晰可见，胚胎成活率为97％；胚胎移植后，代孕母鼠共移植胚胎228枚，经17～19d的妊娠期后，产仔37只（2只死胎），产仔率为16％；有35只仔鼠（雄鼠18只，雌鼠17只）存活到可以判断毛色，共获得8只S8细胞毛色嵌合体小鼠，嵌合体的产生率为21．6％。结果表明用S8细胞经囊胚注射后能够获得嵌合体，并且嵌合体明显发生了性偏离现象。本试验为国内利用囊胚注射携带LacZ基因的胚胎干细胞获得嵌合体小鼠的首例报道。 相似文献
15.
Pluripotent stem cells--model of embryonic development,tool for gene targeting,and basis of cell therapy 总被引：2，自引：0，他引：2
Embryonic stem (ES) cells are pluripotent cell lines with the capacity of self-renewal and a broad differentiation plasticity. They are derived from pre-implantation embryos and can be propagated as a homogeneous, uncommitted cell population for an almost unlimited period of time without losing their pluripotency and their stable karyotype. Murine ES cells are able to reintegrate fully into embryogenesis when returned into an early embryo, even after extensive genetic manipulation. In the resulting chimeric offspring produced by blastocyst injection or morula aggregation, ES cell descendants are represented among all cell types, including functional gametes. Therefore, mouse ES cells represent an important tool for genetic engineering, in particular via homologous recombination, to introduce gene knock-outs and other precise genomic modifications into the mouse germ line. Because of these properties ES cell technology is of high interest for other model organisms and for livestock species like cattle and pigs. However, in spite of tremendous research activities, no proven ES cells colonizing the germ line have yet been established for vertebrate species other than the mouse (Evans and Kaufman, 1981; Martin, 1981) and chicken (Pain et al., 1996). The in vitro differentiation capacity of ES cells provides unique opportunities for experimental analysis of gene regulation and function during cell commitment and differentiation in early embryogenesis. Recently, pluripotent stem cells were established from human embryos (Thomson et al., 1998) and early fetuses (Shamblott et al., 1998), opening new scenarios both for research in human developmental biology and for medical applications, i.e. cell replacement strategies. At about the same time, research activities focused on characteristics and differentiation potential of somatic stem cells, unravelling an unexpected plasticity of these cell types. Somatic stem cells are found in differentiated tissues and can renew themselves in addition to generating the specialized cell types of the tissue from which they originate. Additional to discoveries of somatic stem cells in tissues that were previously not thought to contain these kinds of cells, they also appear to be capable of developing into cell types of other tissues, but have a reduced differentiation potential as compared to embryo-derived stem cells. Therefore, somatic stem cells are referred to as multipotent rather than pluripotent. This review summarizes characteristics of pluripotent stem cells in the mouse and in selected livestock species, explains their use for genetic engineering and basic research on embryonic development, and evaluates their potential for cell therapy as compared to somatic stem cells. 相似文献
16.
Minhua Hu Hengxi Wei Jingfeng Zhang Yinshan Bai Fenglei Gao Li Li Shouquan Zhang 《畜牧与生物技术杂志(英文版)》2013,4(1):12
Background
Production of chimeric mice is a useful tool for the elucidation of gene function. After successful isolation of embryonic stem (ES) cell lines, there are many methods for producing chimeras, including co-culture with the embryos, microinjection of the ES cells into pre-implantation embryos, and use of tetraploid embryos to generate the full ES-derived transgenic mice. Here, we aimed to generate the transgenic ES cell line, compare the production efficiency of chimeric mice and its proportion to yield the male chimeric mice by microinjected ES cells into 4- to 8-cell and blastocysts embryos with the application of Piezo-Micromanipulator (PMM), and trace the fate of the injected ES cells.Results
We successfully generated a transgenic ES cell line and proved that this cell line still maintained pluripotency. Although we achieved a satisfactory chimeric mice rate, there was no significant difference in the production of chimeric mice using the two different methods, but the proportion of the male chimeric mice in the 4- to 8-cell group was higher than in the blastocyst group. We also found that there was no tendency for ES cells to aggregate into the inner cell mass using in vitro culture of the chimeric embryos, indicating that they aggregated randomly.Conclusions
These results showed that the PMM method is a convenient way to generate chimeric mice and microinjection of ES cells into 4- to 8-cell embryos can increase the chance of yielding male chimeras compared to the blastocyst injection. These results provide useful data in transgenic research mediated by ES cells. 相似文献17.
Putative embryonic stem cell lines from pig embryos 总被引：2，自引：0，他引：2
Embryonic stem cells (ES cells) were first established in the mouse, and they represent a population of pluripotent, undifferentiated cells derived from early embryos that is capable of proliferating without any limitation in an undifferentiated state. These cells retain the ability to differentiate in vitro or in vivo into derivates of all three germ layers, and when injected into blastocysts, they can participate in the formation of all tissues, including gonads (germ-line chimeras). It is possible to transfect them with a gene of interest, and the resulting transgenic cell lines can also be used for production of chimeras. Unfortunately, mammalian germ-line chimeras that can carry an inserted gene into their progeny have only been produced in the mouse. Logically, before application of stem cell therapies into a human medicine, it is necessary to verify the efficiency and safety of these methods with an acceptable animal model. The pig is currently used as a very convenient animal for pre-clinical applications, and therefore establishment of porcine ES cell lines is highly needed; unfortunately, no convincing ES cell lines have been produced in this species (and other domestic animals) to date. In this article, we discuss the recent advances in this field, especially oriented on possible reasons and obstacles why derivation of porcine ES cell lines is still unsuccessful. 相似文献
18.
19.
生殖细胞来源于原始生殖细胞,其在体内的分化机制已基本清楚。随着生殖细胞研究的不断深入,通过体外诱导途径获得生殖细胞已成为现实。将胚胎干细胞体外分化为上胚层样细胞,进而分化为原始生殖样或原始生殖细胞。将它们迁移入胎儿生殖腺,具有减数分裂及产生精子能力,与卵子结合移入缺生精管的生殖腺的新生鼠可以产生健康后代。为此,体外诱导生殖细胞的成功,进一步阐明了胚胎干细胞向生殖细胞分化的机制,为更有效利用干细胞造福人类奠定了基础。 相似文献