Miyazaki M, Mihara K, Bai L, Kano Y, Tsuboi S, Endo A, Seshimo K, Yoshioka T, Namba M
Department of Cell Biology, Okayama University Medical School, Japan.
Exp Cell Res. 1993 May;206(1):27-35. doi: 10.1006/excr.1993.1116.
The cells derived from the human embryo liver tissue were transfected with a plasmid pSV3neo containing both the large and small T-antigen gene of the early region of simian virus 40 (SV40), and two cell strains, OUMS-21 and -22, were obtained. OUMS-22 cells, to date, have reached over 100 population doublings through a culture crisis and are considered to have become an immortal cell line. However, OUMS-21 cells failed to become an immortal cell line. Both OUMS-21 and -22 cells were SV40 T-antigen-positive, epithelial-like, and immunoreactive against an anti-keratin 18 monoclonal antibody but against neither an anti-vimentin nor an anti-von Willebrandt factor VIII monoclonal antibody. The staining pattern of cytokeratin in these cells was similar to that in the differentiated human hepatoblastoma and hepatocellular carcinoma cell lines but not to that in the human cholangiocellular carcinoma cell lines. OUMS-21 and -22 cells expressed neither alpha-fetoprotein nor albumin mRNAs. These cells showed no tyrosine aminotransferase activity. However, both OUMS-21 and -22 cells were sensitive to cytotoxicity of aflatoxin B1, 3-amino-1,4-dimethyl-5H-pyrido[4,3-b]indole, and benzo[a]pyrene, whereas human embryo lung fibroblasts were insensitive to the cytotoxicity of these carcinogens. These findings suggest that OUMS-21 and -22 cells may arise from undifferentiated liver stem cells or from hepatocytes that lost their ability to express the liver-specific functions prior to immortalization. Both OUMS-21 and -22 cells expressed glutathione S-transferase pi (GST-pi) mRNA. The expression of GST-pi mRNA highly increased in OUMS-22 cells with their immortalization. Karyotypic analysis showed that numerical and structural aberrations of the chromosomes were profound, but neither specific events nor marker chromosomes were found in OUMS-21 and -22 cells. Both OUMS-21 and -22 cells could grow in soft agar, but they were not tumorigenic when transplanted into nude mice.
用人胚胎肝组织来源的细胞，用含有猿猴病毒40（SV40）早期区域的大T抗原基因和小T抗原基因的质粒pSV3neo进行转染，获得了两个细胞株OUMS - 21和OUMS - 22。到目前为止，OUMS - 22细胞已通过培养危机达到100多次群体倍增，被认为已成为永生细胞系。然而，OUMS - 21细胞未能成为永生细胞系。OUMS - 21和OUMS - 22细胞均为SV40 T抗原阳性，呈上皮样，对抗角蛋白18单克隆抗体有免疫反应，但对抗波形蛋白和抗血管性血友病因子VIII单克隆抗体均无反应。这些细胞中细胞角蛋白的染色模式与分化的人肝母细胞瘤和肝细胞癌细胞系中的相似，但与人类胆管细胞癌细胞系中的不同。OUMS - 21和OUMS - 22细胞均不表达甲胎蛋白和白蛋白mRNA。这些细胞没有酪氨酸转氨酶活性。然而，OUMS - 21和OUMS - 22细胞对黄曲霉毒素B1、3 - 氨基 - 1,4 - 二甲基 - 5H - 吡啶并[4,3 - b]吲哚和苯并[a]芘的细胞毒性敏感，而人胚胎肺成纤维细胞对这些致癌物的细胞毒性不敏感。这些发现表明，OUMS - 21和OUMS - 22细胞可能来源于未分化的肝干细胞，或者来源于在永生化之前失去表达肝特异性功能能力的肝细胞。OUMS - 21和OUMS - 22细胞均表达谷胱甘肽S - 转移酶pi（GST - pi）mRNA。随着OUMS - 22细胞的永生化，GST - pi mRNA的表达显著增加。核型分析表明，染色体的数量和结构畸变严重，但在OUMS - 21和OUMS - 22细胞中未发现特定事件或标记染色体。OUMS - 21和OUMS - 22细胞均可在软琼脂中生长，但移植到裸鼠体内时不具有致瘤性。
