Germ-line Competent Chimeric Mice Derived from Es Cells of EGFP-transgenic Mouse

Generation of germline chimera is the key step in ES cell-mediated transgenesis, whereas the production of chimera, especially germline competent, is the only way to prove whether such potency is maintained. In this experiment, an established ES cell line expressing strong green fluorescence was used to produce chimera mice. After cell passage, ES cells were microinjected into KM's blastocysts. Nine EGFP-expressing chimeric mice were produced including eight male and one female. They developed into healthy adults. Results of a flow cytometry test showed the existence of GFP in several mice tissues: heart (77.96±15.78)%, spleen (84.06±3.60)%, kidney (42.49±19.79)% and marrow (52.02±18.78)%. The ES cell line proved to be important for the germ-line in contributing to the coat-color analysis of offspring(F1), produced by the cross between a female KM mouse and a male chimeric mouse.