Markoulaki Styliani, Meissner Alexander, Jaenisch Rudolf
The Whitehead Institute for Biomedical Research, Cambridge, MA 02142, USA.
Methods. 2008 Jun;45(2):101-14. doi: 10.1016/j.ymeth.2008.04.002. Epub 2008 Jun 2.
Addressing the fundamental questions of nuclear equivalence in somatic cells has fascinated scientists for decades and has resulted in the development of somatic cell nuclear transfer (SCNT) or animal cloning. SCNT involves the transfer of the nucleus of a somatic cell into the cytoplasm of an egg whose own chromosomes have been removed. In the mouse, SCNT has not only been successfully used to address the issue of nuclear equivalence, but has been used as a model system to test the hypothesis that embryonic stem cells (ESCs) derived from NT blastocysts have the potential to correct--through genetic manipulations--degenerative diseases. This paper aims to provide a comprehensive description of SCNT in the mouse and the derivation of ESCs from blastocysts generated by this technique. SCNT is a very challenging and inefficient procedure because it is technically complex, it bypasses the normal events of gamete interactions and egg activation, and it depends on adequate reprogramming of the somatic cell nucleus in vivo. Improvements in any or all those aspects may enhance the efficiency and applicability of SCNT. ESC derivation from SCNT blastocysts, on the other hand, requires the survival of only a few successfully reprogrammed cells, which have the capacity to proliferate indefinitely in vitro, maintain correct genetic and epigenetic status, and differentiate into any cell type in the body--characteristics that are essential for transplantation therapy or any other in vivo application.
几十年来，解决体细胞中核等价性的基本问题一直吸引着科学家们，并推动了体细胞克隆技术（SCNT）或动物克隆技术的发展。体细胞克隆技术涉及将体细胞的细胞核转移到一个已去除自身染色体的卵细胞的细胞质中。在小鼠中，体细胞克隆技术不仅成功用于解决核等价性问题，还被用作一个模型系统来验证以下假设：通过基因操作，从核移植囊胚中获得的胚胎干细胞（ESC）有潜力纠正退行性疾病。本文旨在全面描述小鼠中的体细胞克隆技术以及从通过该技术产生的囊胚中获得胚胎干细胞的过程。体细胞克隆技术是一个极具挑战性且效率低下的过程，因为它技术复杂，绕过了配子相互作用和卵子激活的正常过程，并且依赖于体细胞在体内的充分重编程。在任何或所有这些方面的改进都可能提高体细胞克隆技术的效率和适用性。另一方面，从体细胞克隆技术产生的囊胚中获得胚胎干细胞，仅需要少数成功重编程的细胞存活，这些细胞能够在体外无限增殖，维持正确的遗传和表观遗传状态，并分化为体内的任何细胞类型——这些特性对于移植治疗或任何其他体内应用至关重要。
