Immortalization of multipotent stem cells by using the oncogene transgenic mice

为了建立多种永生化的多能干细胞系，利用携带猴病毒40(SV40)温敏T抗原(ts抗原)基因的转基因小鼠，将分离的干细胞与骨髓基质细胞系共培养，并依赖于基质细胞使两个未成熟的造血干细胞系永生化，以建立多能干细胞系。其中一个细胞系是B淋巴样干细胞系，可以自我更新，并致力于分化更成熟的B细胞。从转基因小鼠中获得了具有干细胞表面标志的其他细胞系，可以分化为更成熟的造血细胞。制备了几只携带bcl2基因、c-kit基因和s1基因的转基因小鼠，并将其用于原始生殖细胞的永生化，这些转基因小鼠的生殖细胞在培养中表现出长期的维持，但尚未观察到永生化。从转基因小鼠中也建立了胃粘膜细胞，并显示了正常胃粘膜细胞的特殊功能，包括产生糖蛋白、碳酸氢盐和前列腺素等保护性因子。

To establish a variety of immortalized multipotent stem cell lines, the transgenic mice harboring temperature-sensitive T-antigen (ts-antigen) gene of simian virus 40 (SV40) were used.To establish multipotent hematopoietic stem cell lines, the sorted stem cells were cocultured with the bone marrow stromal cell lines and two immature hematopoietic stem-like cell lines were immortalized depending on thr stromal cells. One cell line is a B-lymphoid stem cell line and self-renewed as well as committed to differentiate more mature B cells. The other cell lines were obtained from the transgenic mice and exhibited surface markers of the stem cells and can be differentiated to more mature hematopoietic cells.Several transgenic mice with bcl-2 gene, c-kit gene, or Sl gene were made and used to immortalize primordial germ cells, and the germ cells from such transgenic mice showed their prolonged maintenance in culture, but the immortalization was not yet observed.Gastric mucosal cells were also established fro the transgenic mice and showed specific functions of normal gastric mucosal cells including production of protective factors such as glycoproteins, bicarbonate, and prostaglandins.