远交系小鼠胚胎干细胞系的建立及嵌合鼠的获得

ＥＳ细胞（ＥｍｂｒｙｏｎｉｃＳｔｅｍＣｅｌｌｓ）是来源于小鼠早期胚胎的多潜能干细胞，它可以在体外大量培养。并以单细胞的形式注射到早期胚胎里，发育为嵌合体。到目前为止，通常使用的１２９小鼠品系是来源于近交系（ｉｎｂｒｅｄ）小鼠的胚胎．与之相比，远交系小鼠应当具有较强的生命力和抗病能力。曾有人报道过建成了远交系小鼠胚胎干细胞系，但是尚没有见到获得嵌合鼠的报道。有人甚至认为：由于不同品系小鼠所具有的遗传背景不同，有的小鼠不能建成ＥＳ细胞系。最近，本实验室在这方面做了有益的探索，成功地建成了远交系小鼠胚胎干细胞系，并在这里报导首例用远交系小鼠胚胎干细胞系培育成功嵌合体小鼠。采用源于Ｓｗｉｓｓ小鼠远交群的昆明（ＫＭ）品系小鼠囊胚建成了三个小鼠胚胎干细胞系（ＫＥ１．ＫＥ２．ＫＥ５）。核型正常率均达到７０％以上。自第八代起分批冻存，复苏后，培养至第１２代，消化成单细胞，通过囊胚显微注射，将其注射到６１５品系小鼠胚胎。在幸存的幼鼠中获得了一只来源于ＫＥ１细胞的嵌合鼠（Ｔａｂｌｅ１）．其毛色表现为受体鼠（６１５）的白色中嵌合有供体鼠（ＫＭ）的黑褐色（ＰｌａｔｅＩ－Ａ）．嵌合鼠与受体鼠的杂交后代鼠中仍然出现了受体鼠的毛色类型（

Establishment of Embryonic Stem Cell Lines Derived from Outbred Mouse Embryos and Production of Chimeras

The aim of the present investigation was to determine if embryonic stem (ES) cells could be isolated from outbred mouse embryos (KM) and if chimeras could be producedly using outbred ES cells. Three ES cell lines,designated KE1, KE2, and KE5,were isolated from 5 Kunming albino blastocysts. Normal diploid composition of these cell lines was above 70%. By using C57BL/6J and 615 blastocysts as host embryos, one chimera was obtained in living pups. It was shown for the first time that chimeras can be produced by using outhred ES cells. This work implies that to establish ES cell lines from other animal embryos is possible. More interestingly, white color dots from ES cells on the coat of this chimeric mouse enlarged a lot after half a year, indicated that ES cells were inhibited by cells from outbred mouse or the cells of outbred mouse grew vigiously.