Generation of tripotent neural progenitor cells from rat embryonic stem cells.

Rat is a valuable model for pharmacological and physiological studies. Germline-competent rat embryonic stem (rES) cell lines have been successfully established and the molecular networks maintaining the self-renewing, undifferentiated state of rES cells have also been well uncovered. However, little is known about the differentiation strategies and the underlying mechanisms of how these authentic rat pluripotent stem cells give rise to specific cell types. The aim of this study is to investigate the neural differentiation capacity of rES cells. By means of a modified procedure based on previous publications - combination of mitogen-activated protein kinase (MAPK) and glycogen synthase kinase 3 (GSK3) inhibitors (two inhibitors, "2i") with feeder-conditioned medium, we successfully obtained high-quality rat embryoid bodies (rEBs) from rES cells and then differentiated them to tripotent neural progenitors. These rES cell-derived neural progenitor cells (rNPCs) were capable of self-renewing and giving rise to all three neural lineages, including astrocytes, oligodendrocytes, and neurons. Besides, these rES cell-derived neurons stained positive for γ-aminobutyric acid (GABA) and tyrosine hydroxylase (TH). In summary, we develop an experimental system for differentiating rES cells to tripotent neural progenitors, which may provide a powerful tool for pharmacological test and a valuable platform for studying the pathogenesis of many neurodegenerative disorders such as Parkinson's disease and the development of rat nervous system.