家畜生殖细胞移植与睾丸组织异种移植

生殖细胞从可育的供体小鼠移植到不育的受体小鼠的睾丸中可以导致供体小鼠的精子发生,使得供体的遗传物质可以传递到受体的后代中。生殖细胞移植技术可以为研究雄性生殖干细胞系生理特性提供一种生物鉴定方法、开发一种分离培养精原干细胞技术以及检查精子发生的缺陷和治疗雄性不育问题的研究体系。尽管大部分研究都是在小鼠中进行的,生殖细胞移植已经用于大型哺乳动物。在家畜包括猪、山羊、牛以及灵长目动物中,通过超声波辅助以中空管子进入睾丸网将生殖细胞移植到受体睾丸。生殖细胞可以在无亲缘关系的免疫正常的猪或山羊中移植成功,然而在啮齿动物中却要求受体与供体同系或者受体有免疫缺陷。通过对分离的精原干细胞系进行基因操作,可以移植到受体生产转基因精子。雄性生殖细胞的转基因技术在家畜品种改良上具有巨大的应用前景,特别是在那些胚胎干细胞技术无法实现或当前方法生产转基因动物效率低下的情况。异种睾丸组织移植在多种哺乳动物包括马、灵长目中实现,为研究精子生成、检验药物提供了一种潜在的新颖方法。这对于提高或抑制雄性生育能力以及从供体不成熟精原细胞中生产出成熟的精子提供了理论依据。因而,生殖细胞的移植或睾丸组织的异种移植技术对家畜繁殖力的研究、维持以及改良具有特殊的意义。     

雄性生殖系干细胞的研究进展

睾丸干细胞群移植技术的发展及转基因技术的运用,将为生殖基础科学和家畜及野生动物资源保护、雄性不育治疗、转基因动物生产、基因治疗等提供一条新的途径。本文主要介绍了雄性生殖系干细胞的研究进展,其中包含睾丸内主要细胞之间相互调控的作用以及各种细胞分离培养建系和应用,精原干细胞移植的生物学研究模式,移植进雄性体内精原干细胞如何产生能分化成精子的子代细胞。     

精原干细胞的体外培养及其潜在治疗应用价值

精原干细胞(SSCs)能够自我更新,产生大量分化的生殖细胞并在出生以后形成精子,将遗传信息传递给下一代。因为所有雌性生殖干细胞在出生前已停止增殖,所以SSCs是成年哺乳动物唯一的生殖干细胞。将有生育能力的雄性供体睾丸细胞移植到不育症雄性睾丸细胞中,不育症的雄性可以重新进行精子发生和恢复生育能力。这项移植技术已经用来研究SSCs的生物学特性。研究发现,精原干细胞可以在小鼠的曲细精管进行复制,然后迁移,精原干细胞所需自我更新的生长因子保存在哺乳动物中。因此相信该培养技术很快会被应用于人类的精原干细胞中。本文讨论了现有的和潜在的运用移植技术和体外培养精原干细胞的方法。由于辅助的生殖技术能使精子细胞进入卵母细胞使之受精,所以在体外培养分化精原干细胞使之成为成熟生殖细胞的技术,将会促使人的临床精原干细胞的应用得到长足发展。     

精原干细胞移植相关技术研究进展

精原干细胞的分离培养及移植等相关技术对于雄性动物不育、精子发生机理的研究及转基因新技术的建立都具有重要意义.虽然小鼠精原干细胞的生物学特性已经研究得较为清晰,并建立了较为成熟的分离、纯化、培养技术体系,其受体制备和移植技术也较为成熟,但是,技术效率仍然很低.对小鼠精原干细胞生物学特性、分离培养及受体制备与移植方法的分析总结,将对于细胞制备最佳时机的确定、已有精原干细胞分离纯化、培养和受体准备及移植方法的改进提高起到重要的推动作用,也为今后大型动物的相关研究指明了方向.     

精原干细胞研究进展

精原干细胞是雄性哺乳动物精子发生过程的起始细胞,是一群具有自我更新和分化潜能的细胞。自大鼠精原干细胞异体移植获得成功以来,精原干细胞一直是干细胞研究的热点。本文根据国内外相关研究进展,对精原干细胞的生物学特性、功能调控因子、体外培养和移植等作一综述。     

行业资讯

<正>世界首例绵羊精原干细胞移植实验获得成功近日,世界首例绵羊精原干细胞移植实验在内蒙古大学获得成功。内蒙古大学教授吴应积带领研究团队通过这项实验,成功地繁育了供体的后代。     

精原干细胞移植在家畜生产中的应用

本文阐述了精原干细胞的分离纯化、冷冻保存、移植等一系列相关研究技术 ,同时围绕国内外最新研究进展展望了精原干细胞在家畜生产上的潜在应用     

精原干细胞研究进展

精原干细胞（spermatogonial stem cells,SSCs）是各种雄性动物生殖细胞的母细胞,是一群具有自我更新和分化潜能的细胞,并且在雄性个体中精原干细胞与下一代的遗传背景密切相关。因此,精原干细胞在细胞生物学、医学、转基因等领域的研究有着广阔的应用前景。文章根据国内外相关研究进展,对精原干细胞的生物学特性、分离纯化与培养、移植等作一概述。     

精原干细胞移植的研究进展

精原干细胞移植原理与其它细胞移植原理相似,主要利用显微注射法,将供体的精原千细胞移入受体睾丸内,使其能够继续进行生精过程。结合精原干细胞分离培养、纯化、冷冻,该技术开创了基因工程和家畜生产的新途径。本文对精原干细胞的分离培养、纯化、冷冻,以及同源移植和异源移植进行了简要综述。     

利用高科技不生育无角多赛克公羊当“爹”

<正>无角多赛克公羊与蒙古母绵羊共同产下6只小羔羊,仅有1只是无角多赛克的后代,5只是纯正的蒙古羊后代。内蒙古大学近日披露,该校吴应积教授的研究团队利用精原干细胞移植技术取得世界首例绵羊精原干细胞移植产生供体公绵羊的后代。精原干细胞移植是一种以雄性生殖系为基础的新的哺乳动物繁殖技术,在精原干细胞精子发生过程研究、医学研究及转基因     

Male Germ Cell Transplantation

Transplantation of male germ line stem cells from a donor animal to the testes of an infertile recipient was first described in 1994. Donor germ cells colonize the recipient's testis and produce donor-derived sperm, such that the recipient male can distribute the genetic material of the germ cell donor. Germ cell transplantation represents a functional reconstitution assay for male germ line stem cells and as such has vastly increased our ability to study the biology of stem cells in the testis and define phenotypes of infertility. First developed in rodents, the technique has now been used in a number of animal species, including domestic mammals, chicken and fish. There are three major applications for this technology in animals: first, to study fundamental aspects of male germ line stem cell biology and male fertility; second, to preserve the reproductive potential of genetically valuable individuals by male germ cell transplantation within or between species; third, to produce transgenic sperm by genetic manipulation of isolated germ line stem cells and subsequent transplantation. Transgenesis through the male germ line has tremendous potential in species in which embryonic stem cells are not available and somatic cell nuclear transfer has limited success. Therefore, transplantation of male germ cells is a uniquely valuable approach for the study, preservation and manipulation of male fertility in animals.     

精原干细胞的分选、培养及转基因应用探讨

精原干细胞(spermatogonial stem cells,SSCs)是成年哺乳动物精子发生的基础,具有自我更新和定向分化潜能,能够向后代传递遗传信息。利用SSCs的特点,可以建立转基因动物制作的技术,即分离SSCs、体外培养增殖、基因转染、移植、交配获得转基因动物后代的技术路线,有望应用于家畜经济性状的基因改良。     

精原干细胞体外培养研究进展

精原干细胞（SSCs）是指位于睾丸生精小管基膜上既能自我更新维持自身群体数量恒定,又能定向分化形成精母细胞,最终形成精子的一类原始干细胞。其体外培养以及近年来兴起的移植、基因转染的深入研究,为探讨精子的发生机制、重建不育个体的精子发生、生产转基因动物提供了新的途径。文章综述了精原干细胞体外培养的研究现状,并对其体外的纯化、鉴定,以及未来的应用进行了介绍,旨在为精原干细胞的研究提供借鉴。     

Ultrasound Guided Transplantation of Enriched and Cryopreserved Spermatogonial Cell Suspension in Goats

Spermatogonial stem cells transplantation provides a unique approach for studying spermatogenesis. Initially developed in mice, this technique has now been extended in farm animals and provides an alternative means to preserve valuable male germ line and to produce transgenic animals. The aim of this study was to enrich type A spermatogonial cells amongst the isolated cells from goat testis, to cryopreserve these enriched populations of cells and their subsequent transplantation in unrelated recipient goats under ultrasound guidance. The cells were isolated enzymatically and enriched by differential plating and separation on discontinuous percoll gradient. Ultrasound guided injection of trypan blue dye into rete testis resulted in 20–30% filling of the seminiferous tubules. Prior to transplantation, the cells were labelled with a fluorescent dye to trace donor cells in recipient seminiferous tubules after transplantation. The fluorescent‐labelled cells were observed up to 12 weeks after transplantation.     

Transduction and Transplantation of Spermatogonia into the Testis of Ram Lambs through the Extra-testicular Rete

Spermatogonial transplantation will provide a new way to study spermatogenesis in domestic animals, disseminate male genetics and produce transgenic animals, if efficiency can be improved. We evaluated a 'surgical' method for transplanting donor cells into testes of ram lambs, where the head of the epididymis is reflected, and a catheter introduced into the extra-testicular rete testis. We also tested transduction of ram spermatogonia with a lentiviral (LV) vector as a means to identify permanent colonization, and introduce genes into donor cells. Eight ram lambs, 11- to 13-week olds, were the recipients: in five, spermatogonia were injected into one testis, and the contralateral testis was an un-manipulated control: in two, spermatogonia were injected into one testis and the contralateral was sham-injected: in one, both testes were injected. Six lambs received spermatogonia labelled with a cell-tracking dye and these were collected 1 or 2 weeks after transplantation; three lambs received spermatogonia transduced with a LV vector driving the expression of enhanced Green Fluorescence Protein and these were collected after 2 months. Donor cells were detected by immunohistochemistry in tubules of seven of nine recipient testes. Approximately 22% of tubule cross-sections contained donor cells immediately after transplantation, and 0.2% contained virally transduced cells 2 months after transplantation. The onset of spermatogenesis was delayed, and there were lesions in both injected and sham-injected testes. Despite the effects of the surgery, elongated spermatids were present in one recipient testis 2 months after surgery. The results suggest that, after modifying the surgical and transduction techniques, this approach will be a means to produce good colonization by donor spermatogonia in sheep testes.     

Manipulation of fish germ cell: visualization, cryopreservation and transplantation

Germ-cell transplantation has many applications in biology and animal husbandry, including investigating the complex processes of germ-cell development and differentiation, producing transgenic animals by genetically modifying germline cells, and creating broodstock systems in which a target species can be produced from a surrogate parent. The germ-cell transplantation technique was initially established in chickens using primordial germ cells (PGCs), and was subsequently extended to mice using spermatogonial stem cells. Recently, we developed the first germ-cell transplantation system in lower vertebrates using fish PGCs and spermatogonia. During mammalian germ-cell transplantation, donor spermatogonial stem cells are introduced into the seminiferous tubules of the recipient testes. By contrast, in the fish germ-cell transplantation system, donor cells are microinjected into the peritoneal cavities of newly hatched embryos; this allows the donor germ cells to migrate towards, and subsequently colonize, the recipient genital ridges. The recipient embryos have immature immune systems, so the donor germ cells can survive and even differentiate into mature gametes in their allogeneic gonads, ultimately leading to the production of normal offspring. In addition, implanted spermatogonia can successfully differentiate into sperm and eggs, respectively, in male and female recipients. The results of transplantation studies in fish are improving our understanding of the development of germ-cell systems during vertebrate evolution.     

Development of New Stem Cell-based Technologies for Carnivore Reproduction Research

New reproductive technologies based on stem cells offer several potential benefits to carnivore species. For example, development of lines of embryonic stem cells in cats and dogs would allow for the generation of transgenic animal models, which could be used to advance both veterinary and human health. Techniques such as spermatogonial stem cell transplantation (SSCT) and testis xenografting offer new approaches to propagate genetically valuable individual males, even if they should die before producing sperm. These techniques might therefore have application to the conservation of endangered species of carnivores, as well as to biomedical research. Recently, our laboratory has successfully performed SSCT in the dog, with a recipient dog producing sperm of donor genetic origin. Testis xenografting has been used to produce sperm from pre-pubertal testis tissue from both cats and ferrets. These early steps reinforce the need not only for research on stem cell technologies, but also for additional research into complementary technologies of assisted reproduction in carnivores, so that the widest array of research and clinical benefits can be realized.