Cell–cell interaction modulates neuroectodermal specification of embryonic stem cells

• Published in: Neuroscience letters 2008-06, Vol.438 (2), p.190-195
• Main Authors: Parekkadan, Biju, Berdichevsky, Yevgeny, Irimia, Daniel, Leeder, Avrum, Yarmush, Gabriel, Toner, Mehmet, Levine, John B., Yarmush, Martin L.
• Format: Article
• Language: English
• Subjects: Animals; Biological and medical sciences; Cell Adhesion - physiology; Cell Communication - physiology; Cell Differentiation - physiology; Cell Line; Cell Lineage - genetics; Cell Lineage - physiology; Central Nervous System - cytology; Central Nervous System - embryology; Central Nervous System - metabolism; Coculture Techniques; Connexin 43 - genetics; Connexin 43 - metabolism; Connexin-43; DNA-Binding Proteins - genetics; DNA-Binding Proteins - metabolism; Ectoderm - cytology; Ectoderm - embryology; Ectoderm - metabolism; Embryonic Development - physiology; Embryonic stem cell; Embryonic Stem Cells - cytology; Embryonic Stem Cells - metabolism; Fundamental and applied biological sciences. Psychology; Gap Junctions - metabolism; Green Fluorescent Proteins - genetics; Green Fluorescent Proteins - metabolism; High Mobility Group Proteins - genetics; High Mobility Group Proteins - metabolism; Mice; Microfabricated cell pairs; Neural Cell Adhesion Molecules - metabolism; Neuroectodermal differentiation; Signal Transduction - physiology; SOXB1 Transcription Factors; Vertebrates: nervous system and sense organs
• ISSN: 0304-3940; 1872-7972
• DOI: 10.1016/j.neulet.2008.03.094

The controlled differentiation of embryonic stem (ES) cells is of utmost interest to their clinical, biotechnological, and basic science use. Many investigators have combinatorially assessed the role of specific soluble factors and extracellular matrices in guiding ES cell fate, yet the interaction between neighboring cells in these heterogeneous cultures has been poorly defined due to a lack of conventional tools to specifically uncouple these variables. Herein, we explored the role of cell–cell interactions during neuroectodermal specification of ES cells using a microfabricated cell pair array. We tracked differentiation events in situ, using an ES cell line expressing green fluorescent protein (GFP) under the regulation of the Sox1 gene promoter, an early marker of neuroectodermal germ cell commitment in the adult forebrain. We observed that a previously specified Sox1-GFP+ cell could induce the specification of an undifferentiated ES cell. This induction was modulated by the two cells being in contact and was dependent on the age of previously specified cell prior to coculture. A screen of candidate cell adhesion molecules revealed that the expression of connexin (Cx)-43 correlated with the age-dependent effect of cell contact in cell pair experiments. ES cells deficient in Cx-43 showed aberrant neuroectodermal specification and lineage commitment, highlighting the importance of gap junctional signaling in the development of this germ layer. Moreover, this study demonstrates the integration of microscale culture techniques to explore the biology of ES cells and gain insight into relevant developmental processes otherwise undefined due to bulk culture methods.