Embryonic Stem-Derived Versus Somatic Neural Stem Cells: A Comparative Analysis of Their Developmental Potential and Molecular Phenotype
ABSTRACT Reliable procedures to induce neural commitment of totipotent undifferentiated embryonic stem (ES) cells have provided new tools for investigating the molecular mechanisms underlying cell fate choices. We extensively characterized the developmental potential of ES-induced neural cells obtained using an adaptation of the multistep induction protocol. We provided evidence that ES-derived neural proliferating cells are endowed with stem cell properties such as extensive self-renewal capacity and single-cell multipotency. In differentiating conditions, cells matured exclusively into neurons, astrocytes, and oligodendrocytes. All these features have been previously described in only somatic neural stem cells (NSCs). Therefore, we consider it more appropriate to rename our cells ES-derived NSCs. These similarities between the two NSC populations induced us to carefully compare their proliferation ability and differentiation potential. Although they were very similar in overall behavior, we scored specific differences. For instance, ES-derived NSCs proliferated at higher rate and consistently generated a higher number of neurons compared with somatic NSCs. To further investigate their relationships, we carried out a molecular analysis comparing their transcriptional profiles during proliferation. We observed a large fraction of shared expressed transcripts, including genes previously described to be critical in defining somatic NSC traits. Among the genes differently expressed, candidate genes possibly responsible for divergences between the two cell types were selected and further investigated. In particular, we showed that an enhanced MAPK (mitogen-activated protein kinase) signaling is acting in ES-induced NSCs, probably triggered by insulin-like growth factor-II. This may contribute to the high proliferation rate exhibited by these cells in culture.
Full-textDOI: · Available from: Sergio Ferrari, Sep 26, 2014
- SourceAvailable from: Thomas Graf
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- "NPCs derived from ESCs were cultured in medium containing 20 ng/mL EGF and 10 ng/mL FGF2 as previously described (Colombo et al. 2006). Zrf1 and Pax6 re-expression was obtained by electropoating pCBA Zrf1 3xFlag and pCBA Pax6 3xFlag (Amaxa neural stem cell kit), and selected with neomycin for 6 d. "
ABSTRACT: The molecular mechanisms underlying specification from embryonic stem cells (ESCs) and maintenance of neural progenitor cells (NPCs) are largely unknown. Recently, we reported that the Zuotin-related factor 1 (Zrf1) is necessary for chromatin displacement of the Polycomb-repressive complex 1 (PRC1). We found that Zrf1 is required for NPC specification from ESCs and that it promotes the expression of NPC markers, including the key regulator Pax6. Moreover, Zrf1 is essential to establish and maintain Wnt ligand expression levels, which are necessary for NPC self-renewal. Reactivation of proper Wnt signaling in Zrf1-depleted NPCs restores Pax6 expression and the self-renewal capacity. ESC-derived NPCs in vitro resemble most of the characteristics of the self-renewing NPCs located in the developing embryonic cortex, which are termed radial glial cells (RGCs). Depletion of Zrf1 in vivo impairs the expression of key self-renewal regulators and Wnt ligand genes in RGCs. Thus, we demonstrate that Zrf1 plays an essential role in NPC generation and maintenance.Genes & development 01/2014; 28(2):182-97. DOI:10.1101/gad.228510.113 · 12.64 Impact Factor
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- "The strength of this method is the relative purity of the final product and the ability to generate large numbers of NSCs upon FGF2 addition , whereas weaknesses include the extended time it takes to generate NSCs, 10 days to two weeks, and the variability in the quality of the final product, which can be contaminated with mesodermal derivatives, likely due to the multiple steps. An accelerated version of this approach, which combines the selection and proliferation steps, produces a similar end product (Colombo et al., 2006). The embryoid body selection protocol has also been applied to the derivation of neurons from human as well as mouse ESCs (Carpenter et al., 2001; Zhang et al., 2001). "
ABSTRACT: Embryonic stem cells (ESCs) are a potential source of neural derivatives that can be used in stem cell-based therapies designed to treat neurological disorders. The derivation of specific neuronal or glial cell types from ESCs invariably includes the production of neural stem cells (NSCs). We describe the basic mechanisms of neural induction during vertebrate embryogenesis and how this information helped formulate several protocols used to generate NSCs from ESCs. We highlight the advantages and disadvantages of each approach and review what has been learned about the intermediate stages in the transition from ESC to NSC. Recent data describing how specific growth factors and signaling molecules regulate production of NSCs are described and a model synthesizing this information is presented.Developmental Dynamics 12/2007; 236(12):3255-66. DOI:10.1002/dvdy.21306 · 2.67 Impact Factor