Neurodegenerative diseases and neurotrauma constitute pathological conditions that permit limited improvement and therapy and as a result they represent a social and economical challenge worldwide. Neural stem cells, the dividing precursor cells within the nervous system, can be an invaluable source of donor cells in cell-based therapies for these conditions. However, genes involved in the establishment and maintenance of a neural stem cell state are elusive so far. As a result, the purification of a homogenous population of neural stem cells is extremely difficult and the identity of stem cells in vivo and, often, their precise location are yet to be determined.

We wish to identify novel stem cell state determinants. For this purpose, we use marked ES and primary NSC. First, we generated ES-derived neurospheres (esNSCs) using Sox2 as a marker. ES cells and Sox2^βgeo/+ selection are used to generate a highly purified population of neural stem cells in vitro. This is combined with microarray and/or subtractive screening profiling and proteomics analysis that will lead to identification of novel potential neural stem cell determinants. Functional studies will be initiated on the potential of these candidates to drive ES cells to a neural stem cell state. Our approach is versatile enough to enable us to address the role of signalling molecules involved in neural fate, such as shh, FGFs, Wnts and retinoids. The proliferative, differentiative and epigenetic properties of esNSCs are analysed using molecular markers and by determination of their epigenetic maps on selected genes when compared to pNSCs and parental ES cells.

Identification of new neural stem cell state determinants will give new insights into self-renewal and differentiation processes and allow to more precisely manipulate them in order to enhance their potential for repair and regeneration.