title: Source and nature of embryonic stem cells.
abstract: The originally described method of isolation of mouse ES cells was from implantationally-delayed blastocysts that were subsequently explanted into tissue culture. The cell colony arising from the ICM proliferation was disaggregated and cultures established on mitotically inactivated fibroblast feeder layers. The use of delayed blastocysts is advantageous, but not essential, and ES cells have been similarly derived by explantation of cleavage-stage embryos and also early embryonic epiblast. ES cells are probably not homologous to ICM cells, but may better match five-day epiblast.
authors.affiliation: Cardiff School of Biosciences, Cardiff University, Museum Avenue, PO Box 911, Cardiff CF10 3US, UK. evansmj@cf.ac.uk
authors.forename: Martin
authors.initials: M
authors.lastname: Evans
authors.forename: Susan
authors.initials: S
authors.lastname: Hunter
mesh_terms: D000818:Animals; D001755:Blastocyst / Q000166:cytology*; D018929:Cell Culture Techniques / Q000379:methods; D002455:Cell Division; D010064:Embryo Implantation / Q000502:physiology; D004622:Embryo, Mammalian; D051379:Mice; D013234:Stem Cells / Q000166:cytology*