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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
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综述了畜禽胚胎干细胞的生物学特性,主要畜禽胚胎干细胞的已有成果及培养早期胚胎干细胞的技术要点,并展望了人们对畜禽胚胎干细胞的应用前景。 相似文献
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综述了畜禽胚胎干细胞的生物学特性,主要畜禽胚胎干细胞的已有成果及培养早期胚胎干细胞的技术要点,并展望了人们对畜禽胚胎干细胞的应用前景. 相似文献
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为了研究影响胚胎干细胞(ESC)体外分离克隆的因素,试验采用3~5日龄大鼠心肌细胞制成心肌细胞条件培养基(RH-CM),比较了4种培养体系对小鼠胚胎干细胞体外培养的影响,并分析比较了不同饲养层对胚胎干细胞分离克隆造成的影响。结果表明:添加重组鼠白血病抑制因子和心肌细胞条件培养基在胚胎贴壁率、内细胞团(ICM)形成率和原代胚胎干细胞集落形成率以及抑制分化的过程中起到的作用显著优于未添加任何诱导成分的培养基;作为饲养层,小鼠胚胎成纤维细胞(MEF)分离培养胚胎干细胞的效果优于小鼠睾丸支持细胞(MS)。 相似文献
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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
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胚胎干细胞及种系嵌合体的研究进展 总被引:1,自引:0,他引:1
胚胎干细胞是着床前的囊胚内细胞团或早期胎儿的原始生殖细胞经体外分化抑制培养建立的多能性细胞系 ,具有与胚胎细胞相似的形态特征和分化潜能 ,体外培养时保持未分化状态 ,可以传代增殖。改变维持胚胎干细胞不分化的培养条件 ,胚胎干细胞可自发分化成多细胞结构。在一定诱导下 ,胚胎干细胞可向多个方向分化 ,并生成多种功能细胞。胚胎干细胞注入到胚泡期胚胎或与桑椹期胚胎聚合 ,可以参与包括性腺在内的各种组织的嵌合体的形成。胚胎干细胞在细胞分化与调控 ,胚胎发育 ,遗传病 ,肿瘤 ,免疫和组织或器官移植等研究中显示着广泛的应用前景。而种系嵌合体的获得是实现 ES细胞途径的决定步骤 ,低的种系嵌合率则是制约 ES细胞应用的关键。提高供体 PGCs在受体生殖腺中的比例 ,缩短 ES细胞的体外培养时间 ,以及注入早期发育阶段的受体胚胎等都能提高种系嵌合率。文章从多个方面综述了胚胎干细胞的最新研究成果 ,并着重以禽类 ES细胞为例论述了种系嵌合体的检测方法 ,种系嵌合率的影响因素以及提高种系嵌合率的方法 相似文献
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微生物耐药是威胁人类健康、动物保健和食品安全的重大问题。为减少耐药性及动物源食品的药物残留,迫切需要探索预防和治疗疾病的替代机制,其中之一便是激活先天免疫系统对病原体攻击产生强而持久的非特异性免疫应答,这一过程称为训练免疫,即先天免疫记忆。愈来愈多的研究表明,天然免疫细胞甚至组织驻留干细胞对某些感染和疫苗接种具有保护免受再感染的免疫记忆功能,即先天免疫系统也表现出适应性免疫特征。在兽医研究领域,通过改善先天免疫系统提高家禽抗病能力的概念并不新颖,但极少有可用的、有目的的针对训练免疫的应用研究。通过训练免疫途径增强动物免疫力是一个值得关注的崭新领域,将为设计新型广谱疫苗和寻找新的药物靶点开辟新的途径。笔者综述了训练免疫领域的最新进展,阐述了家禽训练免疫调控及未来研究方向。 相似文献
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CRISPR/Cas系统是一种在细菌和古细菌中发现的获得性免疫系统,由规律成簇间隔短回文重复序列(clustered regularly interspaced short palindromic repeats,CRISPR)和CRISPR相关蛋白(CRISPR-associated proteins,Cas)组成。在此基础上改造获得的CRISPR/Cas9基因定点编辑技术可通过设计小的单链引导RNA(single guide RNA,sgRNA)对目标基因进行定向编辑。家禽作为农业经济动物,能够快速高效地生产蛋和肉产品,是世界范围内重要的蛋白质来源,也是极具价值的脊椎动物发育生物学模型。但是受限于卵生动物特点,家禽的受精卵与蛋黄表面紧密结合,未受精的卵子非常难取出,对家禽单细胞阶段受精卵进行靶向遗传修饰的可行性较低,因而家禽功能基因及转基因研究进展较为缓慢。CRISPR/Cas9基因定点编辑技术相较于其他基因编辑系统操作简单,靶向效率高,极大地推动了家禽功能基因的研究进展,是目前筛选和验证家禽功能基因的最有效的工具之一。文章综述了近年来CRISPR/Cas9在家禽细胞、生长发育和性腺分化、家禽疾病、家禽胚胎编辑和转基因家禽制备上的研究进展,以期为CRISPR/Cas9在家禽上的深入研究和应用提供参考。 相似文献
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畜禽体外培养细胞生长规律研究 总被引:2,自引:0,他引:2
本研究利用组织块贴壁培养法对鲁西黄牛、蒙古马、北京鸭和狼山鸡等4个品种体外培养细胞的生长、分化规律进行了研究。通过绘制其生长曲线和在激光共聚焦显微镜下拍摄细胞生长过程,初步分析成纤维细胞的生长、分化规律。试验结果表明,4个品种的细胞生长曲线均呈明显的“S”形,家畜和家禽的细胞潜伏期和停滞期的长短以及细胞群体倍增时间均有明显差异,蒙古马和狼山鸡体外培养细胞的单个细胞分裂期也有显著差异,蒙古马为97 min,而狼山鸡为85 min。本试验构建的4个品种成纤维细胞系不仅使畜禽遗传资源在细胞水平永久保存下来,而且为分子生物学研究提供宝贵材料。 相似文献
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Eugene Mazimpaka Micheal Tukei Anselme Shyaka Eugene N. Gatari 《Tropical animal health and production》2018,50(4):753-759
A study was conducted in Rukomo sector, Nyagatare district, to determine the status of poultry production. A structured questionnaire was used to collect data from 100 poultry farmers randomly as 20 farmers from each of the five cells. Data were analyzed using SPSS version 16 and presented in chart and tables. The majority of the farmers (84%) reared their poultry in free range system while 10% practiced semi-intensive and only 6% did intensive production. Only 12% of the respondents kept exotic poultry breeds. The breeding stock were mostly obtained from local markets (63%) and the average flock size was about 1–10 birds per homestead (70%). The confinement of poultry at night was either in the main domestic house (33%), in kitchen (32%), or in separate poultry house (35%). Flock records were rare and kept by only 9% of respondents. Poultry products were reportedly at high demand by 87% of respondents and 89% farmers reported profit from their enterprises. Lack of veterinary and financial assistance was reported by 72% of respondents. Newcastle disease (57%) was the main health constraint followed by ectoparasites and internal worms. Many farmers (50%) were in dire need of veterinary assistance and financial support to improve their poultry enterprises. Poor management practices were reported to be one of the crucial factors leading to poor production. Lack of quality feeds (38%) and feeding of poultry, credit (20%), and poor market accessibility (19%) were the main challenges reported. 相似文献
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Van Deun K Pasmans F Ducatelle R Flahou B Vissenberg K Martel A Van den Broeck W Van Immerseel F Haesebrouck F 《Veterinary microbiology》2008,130(3-4):285-297
Although poultry meat is now recognized as the main source of Campylobacter jejuni gastroenteritis, little is known about the strategy used by the bacterium to colonize the chicken intestinal tract. In this study, the mechanism of C. jejuni colonization in chickens was studied using four human and four poultry isolates of C. jejuni. The C. jejuni strains were able to invade chicken primary cecal epithelial crypt cells in a predominantly microtubule-dependent way (five out of eight strains). Invasion of cecal epithelial cells was not accompanied by necrosis or apoptosis in the cell cultures, nor by intestinal inflammation in a cecal loop model. C. jejuni from human origin displayed a similar invasive profile compared to the poultry isolates. Invasiveness of the strains in vitro correlated with the magnitude of spleen colonization in C. jejuni inoculated chicks. The C. jejuni bacteria that invaded the epithelial cells were not able to proliferate intracellularly, but quickly evaded from the cells. In contrast, the C. jejuni strains were capable of replication in chicken intestinal mucus. These findings suggest a novel colonization mechanism by escaping rapid mucosal clearance through short-term epithelial invasion and evasion, combined with fast replication in the mucus. 相似文献