Ke M W, Hsu J T, Jiang Y N, Cheng W T K, Ju Y T
Department of Animal Science and Technology, National Taiwan University, Taipei, Taiwan.
Reprod Domest Anim. 2012 Aug;47(4):553-61. doi: 10.1111/j.1439-0531.2011.01916.x. Epub 2011 Nov 2.
The aim of this article is to demonstrate and characterize caprine mammary epithelial cells (CMC) immortalized with human telomerase reverse transcriptase (hTERT) gene. Five immortalized CMCs were assigned to either myoepithelial or luminal epithelial groups based on their morphology and expression of cell lineage-specific intermediate filaments. Telomeric repeat amplification protocol revealed various telomerase activities in CMCs associated with their distinct proliferation potential. Karyotypic analysis showed three CMCs retained their modal Capra hircus chromosome number (2n = 60), whereas the remaining two CMCs were abnormal at 2n = 19 and 2n = 36. CMCs with abnormal karyotypes lost p53 protein after chemical-induced DNA damage and showed anchorage-independent growth in soft agar assay. In terms of functional differentiation, luminal CMCs organized into alveolus-like structures when grown in Matrigel. Furthermore, αs1- and β-casein gene was induced in luminal CMCs in response to lacto-hormones stimulation. Together these results showed that hTERT-immortalized CMCs retained major characteristics of mammary epithelial cells, and stability of the genome is required for maintaining normal mammary epithelium function. Application of CMCs can provide valuable models to study alveologenesis and lactogenesis of mammary epithelium and test the feasibility of recombinant constructs designed for the generation of transgenic livestock.
本文旨在展示和表征用人端粒酶逆转录酶（hTERT）基因永生化的山羊乳腺上皮细胞（CMC）。根据其形态和细胞谱系特异性中间丝的表达，将五个永生化的CMC分为肌上皮或腔上皮组。端粒重复序列扩增协议揭示了CMC中与它们不同的增殖潜力相关的各种端粒酶活性。核型分析显示三个CMC保留了它们的模式山羊染色体数（2n = 60），而其余两个CMC在2n = 19和2n = 36时异常。核型异常的CMC在化学诱导的DNA损伤后失去p53蛋白，并在软琼脂试验中显示出不依赖贴壁的生长。在功能分化方面，腔CMC在Matrigel中生长时组织成肺泡样结构。此外，αs1-和β-酪蛋白基因在腔CMC中响应乳激素刺激而被诱导。这些结果共同表明，hTERT永生化的CMC保留了乳腺上皮细胞的主要特征，并且基因组的稳定性是维持正常乳腺上皮功能所必需的。CMC的应用可以提供有价值的模型来研究乳腺上皮的肺泡形成和泌乳发生，并测试为生成转基因家畜而设计的重组构建体的可行性。
