Patent ID: 8900861

Claim:
A method of storing a preparation of hES cells in a viable condition comprising (a) taking a preparation of hES cells prepared using method (1) or method (2), (b) adding a cryopreservation agent, and (c) freezing the cells at about −15° C. to about −72° C.; wherein method (1) comprises expanding the cells free of animal products, feeder cells, growth factors, leukaemia inhibitory factor, supplementary mineral combinations, amino acid supplements, vitamin supplements, fibroblast growth factor, membrane associated steel factor, soluble steel factor, and conditioned media, comprising: (i) introducing the cells in a cell culture medium consisting of minimal essential medium, a progestin, and a β-human chorionic gonadotropin (βhCG) agonist; and (ii) incubating the cells at a temperature of about 34° C. to about 38° C. in an environment of about 3.5% to about 6% carbon dioxide for about 12 hours to about 48 hours; and wherein method (2) comprises partially differentiating the cells free of animal products, feeder cells, growth factors, leukaemia inhibitory factor, supplementary mineral combinations, amino acid supplements, vitamin supplements, fibroblast growth factor, membrane associated steel factor, soluble steel factor, and conditioned media, comprising: (i) introducing the cells in a cell culture medium consisting of minimal essential medium; and (ii) incubating the cells at a temperature of about 34° C. to about 38° C. in an environment of about 3.5% to about 6% carbon dioxide for about 12 hours to about 48 hours, wherein the cells are incubated in a biocompatible container under substantially aerobic conditions, and wherein the cells differentiate on proliferation.