Establishment of pluripotent cell lines from vertebrate species - Present status and future prospects

Pluripotent embryonic stem (ES) cells are undifferentiated cell lines deriv ed from early embryos and are capable of unlimited undifferentiated prolife ration in vitro. They retain the ability to differentiate into all cell typ es including germ cells in chimeric animals in vivo, and can be induced to form derivatives of all three germ layers in vitro. Mouse ES cells represen t one of the most important tools in genetic research. Major applications i nclude the targeted mutation of specific genes by homologous recombination and the discovery of new genes by gene trap strategies. These applications would be of high interest for other model organisms and also for livestock species, However, in spite of tremendous research activities, no proven ES cells colonizing the germ line have been established for vertebrate species other than mouse a nd chicken thus far. This review summarizes the current status of deriving pluripotent embryonic stem cell lines from vertebrates and recent developments in nuclear transfer technology, which may provide a n alternative tool for genetic modification of livestock animals. Copyright (C) 1999 S. Karger AG, Basel.