Differentiation of embryonic stem cells into functional neurons in vitro

Embryonic stem (ES) cells are pluripotent cells that are derived from the inner cell mass of blastocysts. We produced neuronal cells by directed differentiation of a newly established murine ES cell line in vitro (Royan B1). Immunohistochemistry, scanning electron microscopy, Campenot's assay and electrophysiology were used to evaluate the differentiated neurons. Antibodies against microtubule-associated protein (MAP2), glutamic acid decarboxylase (GAD) and tyrosine hydroxylase (TH) antigens showed that the cells had GABAergic and dopaminergic characteristics. The Campenot's assay revealed there were a number of peripheral nerveous system related neurons but they were rare. The cells also produced action potentials and responded to electrical stimulation by expressing calcium channels in the processes. We showed therefore that functional neurons can be generated by directed differentiation from embryonic stem cells in vitro.