Kataoka H, Tahara H, Watanabe T, Sugawara M, Ide T, Goto M, Furuichi Y, Sugimoto M
AGENE Research Institute, Kanagawa, Japan.
Differentiation. 1997 Dec;62(4):203-11. doi: 10.1046/j.1432-0436.1998.6240203.x.
The immunological characteristics and immortalization processes of three EBV-transformed human B-lymphoblastoid cell lines, N0003, N0005 and N6803, with strong telomerase and infinitively proliferating activities are described. The three cell lines were apparently immortalized: they developed a strong telomerase activity at the population doubling levels (PDLs) between 11 and 135, and continued proliferation over 250 PDLs. All the cell lines expressed CD22, CD19 and CD20 antigens. They were uniformly stained with IgM (N0005), IgG (N6803) or IgA (N0003) at early PDLs between 17 and 20, and they secreted the corresponding class of Ig into the medium; the N6803 and N0003 cell lines continued to secrete each class of Ig at decreased levels while the N0005 cell line expressed or secreted virtually no Ig after immortalization. Karyotype analysis of the immortalized cell lines showed that they were derived from a single cell because they shared a set of abnormal chromosomes within each cell population, and two of the cell lines attained clonal characteristics before they developed a strong telomerase activity. These results indicate that the three immortalized cell lines with a strong telomerase activity correspond to the intermediate stages of B-cell differentiation naturally committed to a specific Ig class, and suggest that they were derived from a B-lymphoblastoid cell committed to a specific class of Ig with poor telomerase activity, rather than from a strongly telomerase-positive B-lymphoblastoid cell either committed or multipotential.
描述了三种EB病毒转化的人B淋巴细胞系N0003、N0005和N6803的免疫特性及永生化过程，这些细胞系具有强大的端粒酶活性和无限增殖能力。这三种细胞系明显已永生化：它们在群体倍增水平（PDL）达到11至135时产生了强大的端粒酶活性，并在超过250个PDL时持续增殖。所有细胞系均表达CD22、CD19和CD20抗原。在17至20的早期PDL时，它们分别被IgM（N0005）、IgG（N6803）或IgA（N0003）均匀染色，并且它们将相应类别的Ig分泌到培养基中；N6803和N0003细胞系在永生化后继续以降低的水平分泌各类Ig，而N0005细胞系在永生化后几乎不表达或分泌Ig。对永生化细胞系的核型分析表明它们源自单个细胞，因为每个细胞群体内共享一组异常染色体，并且其中两个细胞系在产生强大的端粒酶活性之前就获得了克隆特征。这些结果表明，这三种具有强大端粒酶活性的永生化细胞系对应于自然分化为特定Ig类别的B细胞分化的中间阶段，并表明它们源自具有低端粒酶活性的、致力于特定Ig类别的B淋巴母细胞，而不是源自已分化或具有多能性的、端粒酶强阳性的B淋巴母细胞。
