Transgenic mouse models of HD expressing exon 1 of the human HD gene were developed to mimic the features of the human HD. The R6/2 mouse model has represented the most rapid symptoms with widespread huntingtin inclusions in the brain (Mangiarini et al., 1996; Li et al., 2005; Gil and Rego, 2009). Some therapeutic approaches of neuronal transplantation were analyzed in R6/2 mice aiming to restore dysfunctional neurons. Transplantation of striatal tissue from wild type mice embryos in R6/2 transgenic mice presented a good survival and a well-integrated results within the host brain. However, it was associated with minimal behavioral improvements and no effect on weight loss, which might be due to late transplantation intervention (Dunnett et al., 1998; Gil and Rego, 2009). A more recent protocol combined neural stem cells (NSCs) transplantation with a trehalose enriched diet in R6/2 mice and resulted in more improved motor functions, less aggregations in striatum and extended the lifespan of the animals (Yang and Yu, 2009). This further supports the importance of generating human and patient specific HD-iPS neuron cell models with endogenous
