Generation of cerebellar neuron precursors from embryonic stem cells

Here, we report in vitro generation of Math1⁺ cerebellar granule cell precursors and Purkinje cells from ES cells by using soluble patterning signals. When neural progenitors induced from ES cells in a serum-free suspension culture are subsequently treated with BMP4 and Wnt3a, a significant proportion of these neural cells become Math1⁺. The induced Math1⁺ cells are mitotically active and express markers characteristic of granule cell precursors (Pax6, Zic1, and Zipro1). After purification by FACS and coculture with postnatal cerebellar neurons, ES cell-derived Math1⁺ cells exhibit typical features of neurons of the external granule cell layer, including extensive motility and a T-shaped morphology. Interestingly, differentiation of L7⁺/Calbindin-D28K ⁺ neurons (characteristic of Purkinje cells) is induced under similar culture conditions but exhibits a higher degree of enhancement by Fgf8 rather than by Wnt3a. This is the first report of in vitro recapitulation of early differentiation of cerebellar neurons by using the ES cell system.