The invention relates to methods and reagents for promoting the
differentiation of oligodendrocytes from stem cells, by co-activating the
Olig genes and the Nkx2.2 genes, and the use of the differentiated
oligodendrocytes thus obtained in treating diseases, such as Multiple
Sclerosis (MS). The invention also relates to the use of OLPs and
oligodendrocytes thus obtained for drug screening.