The state of the art for pluripotent stem cells derivation in domestic ungulates

Since the successful isolation, characterization and long-term culture of embryonic stem cells (ESCs) from mice in the early 1980s and from humans a decade later, considerable effort has been made to establish ESCs lines from livestock. The derivation of validated ESCs lines is a necessary step if the generation of economically relevant transgenic animals is to be achieved. However, this is still elusive, as the isolation of true ESCs lines for livestock has not been accomplished to date. It has been demonstrated that by forced expression of a defined set of transcription factors, it is possible to reprogram somatic cells to cells that closely resemble an ES-like state. These cells were termed induced pluripotent stem cells (iPSCs). We introduce the basic concepts relating to stem cell biology and give an overview of the various attempts to isolate and generate pluripotent stem cells (PSCs) from species relevant to livestock production. Further, we point out the issues to be addressed and hurdles to be overcome to realize the promise of stem cells in agriculture.