Derivation of embryonic stem cells across avian species.

Germline-competent embryonic stem (ES) cells have been successfully derived from mice and rats, but not from other species. Here we report the development of culture conditions for deriving ES cells from chickens and seven other avian species. Chicken ES cells express core pluripotency markers and can differentiate into cells of all embryonic germ layers, as well as extra-embryonic lineages. Notably, chicken ES cells contribute to high rates of chimerism when injected into chicken embryos and give rise to germ cells both in vitro and in ovo, confirming their germline competence. In addition, we demonstrated that ES cell self-renewal pathways are conserved among avian species, allowing ES cells from multiple avian species to be established using optimized chicken ES cell culture conditions. The establishment of authentic avian ES cells lays the groundwork for future applications in genetic engineering and the conservation of avian biodiversity.