Figure 3: Transcription factor combinations used by three different groups to generate induced neural stem cells (iNSCs). Three different groups [10-12] recently converted fibroblasts into iNSCs using different transcription factor combinations. Han et al. used Brn4, Sox2, Klf4 and c-Myc while Ring et al. used Sox2 only for conversion into iNSCs. Thier et al. constitutively expressed Sox2, Klf4 and c-Myc, and Oct4 as a recombinant protein ( ) for the first 5 days to generate iNSCs. All three groups demonstrated in their respective studies that these iNSCs exhibit morphology, gene expression and the ability to self-renew similar to NSCs derived from primary tissue. Furthermore, these iNSCs differentiated into neurons, astrocytes and oligodendrocytes suggesting multipotency of these cells.