In Vitro Induction Of Embryonic Stem Cells And Induced Pluripotent Stem Cells Into Neural-like Cells

Retinoic acid (RA) plays multiple roles in the nervous system, including induction of neural differentiation, axon outgrowth and neural patterning. Previously, RA for neural differentiation of embryonic stem cells (ESCs) always relies on embryoid body formation. Here we report an in vitro adherent culture system to induce mouse ESC line R1 into neural cells accompanied with RA. RA (1 ?μM) treatment, during initial 2 days of differentiation, can enhance the expression of neural genes, such as Sox1, Pax6, Nestin, Tuj1 and MAP2, and result in more Nestin, Tuj1 and MAP2 positive cells producing from R1. Furthermore, RA promotes a significant increase neurite elongation of ESC-derived neurons. Our study also implies that RA induced Wnt antagonist Dickkopf-1 (Dkk-1) expression for neural differentiation. The mechanisms of RA triggering neural induction are still obscure. However, our simple and efficient strategy is proposed to provide a basis for RA signaling pathways of neural differentiation studies in vitro.Induced pluripotent stem cells (iPSCs) were successfully directed to differentiate into neural cells generally applied an adherent monoculture system in a serum-free medium. After 6 days'differentiation, both meningeal iPSC clone C5 and mouse embryonic fibroblast (MEF) iPSC clone S103f9 expressed neural markers Pax6, Nestin, Tuj1 and MAP2, while almost no ES marker Oct4 was expressed during the same time. Such results were consistent with that of R1 cells when it cultures in adherent monoculture system. It also means that iPSCs share the similar neural differentiation ability of ESCs. Finally, in vitro differentiation of iPSCs into patient-specific cells could serve as a model to study the mechanisms of genetic disease and promising candidates for therapeutic application to dysfunctional or aging neural tissues.