title: Analysis of factors controlling primary germ layer formation and early hematopoiesis using embryonic stem cell in vitro differentiation.
abstract: Differentiation and subsequent development are intricately interwoven processes operating as an integrated whole to form the organism. As an approach to examine these interactions in early mammalian development, we used embryonic stem (ES) cell in vitro differentiation. ES cells can, depending upon the environment differentiated to neuroectoderm, mesoderm and hematopoietic cells. We developed a serum-free, chemically defined medium (CDM) in which ES cells survive and differentiate. In CDM, in the absence of exogenous factors, ES cells form neuroectoderm, upregulating the early neural marker Pax-6. This is consistent with the view that neuroectoderm development can represent a default state, where the absence or sequestration of mesoderm inducing factors permits neuroectoderm formation. In contrast, if CDM is supplemented with bone morphogenetic protein (BMP) 2 or 4 a process resembling primitive streak formation, least at the molecular level occurs, with the formation of mesoderm and subsequently endothelial and hematopoietic cells. If used with care, ES cell in vitro differentiation can act as a guide in understanding the environment which controls early differentiation events in mammals.
authors.affiliation: Basel Institute for Immunology, Switzerland.
authors.forename: M V
authors.initials: MV
authors.lastname: Wiles
authors.forename: B M
authors.initials: BM
authors.lastname: Johansson
mesh_terms: D000818:Animals; D055415:Bone Morphogenetic Protein 4; D019485:Bone Morphogenetic Proteins / Q000032:analysis / Q000096:biosynthesis; D002454:Cell Differentiation; D002470:Cell Survival; D016895:Culture Media, Serum-Free; D004268:DNA-Binding Proteins / Q000032:analysis / Q000096:biosynthesis; D004475:Ectoderm / Q000166:cytology / Q000502:physiology; D004622:Embryo, Mammalian; D004625:Embryo, Nonmammalian; D005136:Eye Proteins; D006410:Hematopoiesis; D018398:Homeodomain Proteins; D066298:In Vitro Techniques; D008648:Mesoderm / Q000502:physiology; D051379:Mice; D009420:Nervous System / Q000196:embryology; D000071841:PAX6 Transcription Factor; D051761:Paired Box Transcription Factors; D012097:Repressor Proteins; D013234:Stem Cells / Q000166:cytology* / Q000502:physiology*; D014157:Transcription Factors / Q000096:biosynthesis; D014981:Xenopus; D029867:Xenopus Proteins
chemical_list: C525810:Bmp4 protein, mouse; D055415:Bone Morphogenetic Protein 4; D019485:Bone Morphogenetic Proteins; D016895:Culture Media, Serum-Free; D004268:DNA-Binding Proteins; D005136:Eye Proteins; D018398:Homeodomain Proteins; D000071841:PAX6 Transcription Factor; D051761:Paired Box Transcription Factors; C000605732:Pax6 protein, mouse; D012097:Repressor Proteins; D014157:Transcription Factors; D029867:Xenopus Proteins; C525812:bmp4 protein, Xenopus