2009年12月18日,北京生命科学研究所高绍荣实验室在Stem Cells杂志在线发表题为“Generation of Histocompatible Androgenetic Embryonic Stem Cells Using Spermatogenic Cells”的研究论文。该论文报道了采用核移植方法将不同阶段的生精细胞注入去核卵细胞从而成功获得了具有供体组织相容性的孤雄胚胎干细胞(Androgentic Enbryonic Stem Cells, aES cells)。首次证实不同阶段生精细胞都能制备孤雄胚胎干细胞,是组织细胞替代治疗的潜在干细胞来源之一。且不涉及毁坏正常受精胚胎,规避了胚胎干细胞研究应用中这一引人关注的伦理问题。
正常胚胎干细胞来自囊胚内细胞团(Inner Cell Mass,ICM), 具有无限增殖能力以及能分化产生各种细胞和组织的全能性。因而胚胎干细胞具有巨大的潜能用于治疗组织细胞退化性疾病和遗传性疾病。伦理问题以及期望获得病人自身胚胎干细胞的需求,促使进一步寻找其它来源的胚胎样干细胞制备方法。单性胚胎干细胞就是其中之一,其中孤雄胚胎干细胞就是特定制备雄性胚胎干细胞。
以往报道的孤雄胚胎干细胞制备方法是通过去除雌原核后的两个受精卵融合而来的。一方面仍然存在毁坏胚胎的伦理问题,另一方面制备的孤雄胚胎干细胞全能性不尽人意。高绍荣实验室采用细胞核移植的方法,将初级精母细胞(Primary spermatocytes,PS),圆精细胞(round spermatids,RS)和成熟精子(Mature spermatozoa,S)三种不同阶段的生精细胞分别注入去核卵细胞,构建仅含有供体雄性基因组的重组胚胎,即孤雄胚胎。由此分别制备了PS来源的a(PS)ES, RS来源的a(RS)ES和S来源的a(S)ES三类aES细胞。经多能基因mRNA分析和多能因子表达分析,以及畸胎瘤实验证实了这三类aES细胞具有胚胎干细胞的全能性。而且还获得了a(PS)ES和a(RS)ES细胞的嵌合体小鼠。研究中还发现随着培养时间的延长孤雄胚胎干细胞获得了和正常胚胎干细胞相似的基因印迹状态和相似的印迹基因表达水平。体内aES细胞移植实验表明获得的胚胎干细胞具有与供体鼠MHC组织相容的能力。该研究表明孤雄胚胎干细胞能够来源于生精细胞的不同阶段,是获得雄性自体MHC组织相容性胚胎干细胞的有效途径之一。
原始出处:
STEM CELLS 17 Dec 2009 DOI:10.1002/stem.283
Generation of Histocompatible Androgenetic Embryonic Stem Cells Using Spermatogenic Cells
Qingguo Zhao 1, Jianle Wang 1 2, Yu Zhang 1, Zhaohui Kou 1, Sheng Liu 1, Shaorong Gao 1 *
1National Institute of Biological Sciences, Beijing 102206, China
2State Key Laboratory of Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China
Androgenetic embryonic stem (aES) cells, produced by pronuclear transplantation, offer an important autologous pluripotent stem cell source. However, the isolation of aES cells, particularly individual-specific aES cells, using fertilized embryos has limited the practical applications of this technology in humans. In the present study, we applied a new approach, essentially described as somatic cell nuclear transfer (SCNT), and generated three types of aES cell lines using spermatogenic cells including primary spermatocytes (PS), round spermatids (RS) and mature spermatozoa (S) as donor cells, omitting the need to use fertilized embryos. Although abnormality of chimeras and absent germline competency indicated that all three types of aES cells exhibiting limited pluripotency, the epigenetic status of the aES cell lines tended to resemble normal ES cells during long-term culture and some parental-specific imprinted genes were expressed at levels comparable to those of normal ES cells. Furthermore, the histocompatibility of the aES cells was investigated by transplanting the differentiation progenies of the aES cells into MHC-matched and mismatched recipient mice. The results indicated that these aES cells were histocompatible with MHC-matched mice after transplantation. Our study provided evidence indicating that MHC-competent autologous aES cells could be generated from different spermatogenic cells using nuclear transfer into oocytes that could avoid using fertilized embryos.