title: Development of isolated sheep inner cell masses/embryonic discs in vitro.
abstract: Ovine inner cell masses (ICMs)/embryonic discs cultured in vitro, in conditions copying those in which mouse embryonic stem cells (ESCs) arise from mouse blastocysts, give rise to ectodermal colonies. Day 10-11 ICMs/epiblasts produce ectodermal colonies sufficiently often (55-60%) for it to be considered worthwhile trying to generate presumed ESCs from them. Younger ICMs can only be taken into account if culture conditions can be improved so that ICM/ectodermal cells are more numerous. Older embryonic discs (12-13 day) are inconvenient because of the problem of endoderm overgrowing ectoderm. Secondary cultures of ectodermal colonies form epithelial or mesenchymal cells, which can be passaged at least seven times (50 days).
authors.affiliation: Department of Embryology, Institute of Genetics and Animal Breeding, Polish Academy of Sciences, Jastrzebiec, 05-551, Mrokow, Poland.
authors.forename: J
authors.initials: J
authors.lastname: Karasiewicz
authors.affiliation: Department of Embryology, Institute of Genetics and Animal Breeding, Polish Academy of Sciences, Jastrzebiec, 05-551, Mrokow, Poland.
authors.forename: E
authors.initials: E
authors.lastname: Szablisty
authors.affiliation: Department of Embryology, Institute of Genetics and Animal Breeding, Polish Academy of Sciences, Jastrzebiec, 05-551, Mrokow, Poland.
authors.forename: A
authors.initials: A
authors.lastname: Guszkiewicz
authors.affiliation: Department of Embryology, Institute of Genetics and Animal Breeding, Polish Academy of Sciences, Jastrzebiec, 05-551, Mrokow, Poland.
authors.forename: M
authors.initials: M
authors.lastname: Kossakowski
authors.affiliation: Department of Embryology, Institute of Genetics and Animal Breeding, Polish Academy of Sciences, Jastrzebiec, 05-551, Mrokow, Poland.
authors.forename: G
authors.initials: G
authors.lastname: Stefanski
authors.affiliation: Department of Embryology, Institute of Genetics and Animal Breeding, Polish Academy of Sciences, Jastrzebiec, 05-551, Mrokow, Poland.
authors.forename: J
authors.initials: J
authors.lastname: Modlinski
authors.affiliation: Edison Biotechnology Institute, Ohio University, Wilson Hall, West Green, 45701, Athens, OH, USA.
authors.forename: M
authors.initials: M
authors.lastname: Reed
keywords: Embryonic disc; In vitro; Inner cell mass; Sheep