title: Spatial distribution and initial changes of SSEA-1 and other cell adhesion-related molecules on mouse embryonic stem cells before and during differentiation.
abstract: We examined the distribution of cell adhesion-related molecules (CAMs) among mouse embryonic stem (ES) cells and the spatial distribution on cell surfaces before and during differentiation. The cell-cell heterogeneity of SSEA-1, PECAM-1, and ICAM-1 among the undifferentiated cells in the ES cell colonies was evident by immunohistochemistry and immuno-SEM, supporting the flow cytometry findings. In contrast, most undifferentiated ES cells strongly expressed CD9. SSEA-1 was located preferentially on the edge of low protuberances and microvilli and formed clusters or linear arrays of 3-20 particles. PECAM-1 and ICAM-1 were randomly localized on the free cell surfaces, whereas CD9 was preferentially localized on the microvilli or protuberances, especially in the cell periphery. Both the SSEA-1(+) fraction and the SSEA-1(-) fraction of magnetic cell sorting (MACS) formed undifferentiated colonies after plating. Flow cytometry showed that these populations reverted separately again to a culture with a mixed phenotype. Differentiation induced by retinoic acid downregulated the expression of all CAMs. Immuno-SEM showed decreases of SSEA-1 in the differentiated ES cells, although some clustering still remained. Our findings help to elucidate the significance of these molecules in ES cell maintenance and differentiation and suggest that cell surface antigens may be useful for defining the phenotype of undifferentiated and differentiated ES cells.
authors.affiliation: Institute of Organ Transplants, Reconstructive Medicine and Tissue Engineering, Shinshu University Graduate School of Medicine, 3-1-1 Asahi, Matsumoto 390-8621, Japan. cui@sch.md.shinshu-u.ac.jp
authors.forename: Li
authors.initials: L
authors.lastname: Cui
authors.forename: Kohei
authors.initials: K
authors.lastname: Johkura
authors.forename: Fengming
authors.initials: F
authors.lastname: Yue
authors.forename: Naoko
authors.initials: N
authors.lastname: Ogiwara
authors.forename: Yasumitsu
authors.initials: Y
authors.lastname: Okouchi
authors.forename: Kazuhiko
authors.initials: K
authors.lastname: Asanuma
authors.forename: Katsunori
authors.initials: K
authors.lastname: Sasaki
mesh_terms: D000818:Animals; D015703:Antigens, CD / Q000096:biosynthesis*; D002448:Cell Adhesion; D002454:Cell Differentiation; D002478:Cells, Cultured; D004622:Embryo, Mammalian / Q000166:cytology; D005434:Flow Cytometry; D018799:Intercellular Adhesion Molecule-1 / Q000096:biosynthesis*; D016256:Lewis X Antigen / Q000096:biosynthesis*; D008562:Membrane Glycoproteins / Q000096:biosynthesis*; D051379:Mice; D008855:Microscopy, Electron, Scanning; D046529:Microscopy, Electron, Transmission; D019408:Platelet Endothelial Cell Adhesion Molecule-1 / Q000096:biosynthesis*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013234:Stem Cells / Q000166:cytology / Q000378:metabolism* / Q000648:ultrastructure; D060245:Tetraspanin 29; D014212:Tretinoin / Q000494:pharmacology
chemical_list: D015703:Antigens, CD; C554870:Cd9 protein, mouse; D016256:Lewis X Antigen; D008562:Membrane Glycoproteins; D019408:Platelet Endothelial Cell Adhesion Molecule-1; D060245:Tetraspanin 29; D018799:Intercellular Adhesion Molecule-1; D014212:Tretinoin