Fuente: WIPO "biotechnology" Pluripotential embryonic stem cells from non-human and non-rodent blastocysts, which cells are capable of culture in a tissue culture dish to exhibit the following morphological features: (a) they are round cells, tightly packed with large nuclei in relation to cytoplasm, and fairly prominent nucleoli; (b) they grow in tightly adherent colonies, and as the colonies get larger the cells tend to flatten out in the centre of the colony, with the colony having an outer rim of cells of the form described in (a) above, and (c) on trypsinisation of such a colony it may be seen that the outer, less flattened cells of a larger colony or all the cells of a smaller colony without central flattening are readily disaggregated into small spherical cells which have a bright phase contrast appearance, and if observed after a short time of incubation at 37oC show lobular pseudopodia can be isolated from in vitro treatment of such blastocysts. These stem cells may be obtained by growing such blastocysts in tissue culture growth medium which includes both new born calf serum and foetal calf serum (both sera having been heat inactivated before use); causing disaggregation of the blastocysts either after spontaneous hatching or after mechanical removal of the zone pellucida; growing the disaggregated cells in tissue culture growth medium; selecting stem cell colonies by morphological characteristics; and growing the selected stem cells in tissue culture growth medium wherein the morphologically selected cells have the morphological features set out above...