ABSTRACT Although stem cell therapies have been proposed as a candidate for treating neurological diseases, the best stem cell source and their therapeutic efficacy remain uncertain. Embryonic stem cells (ESCs) can efficiently generate multiple cell types, but pose ethical and clinical challenges, while the more accessible adult stem cells have a limited develop-mental potential. Following included-expression of Nanog, an ESC gene, adult human mesenchymal stem cells (HMSCs) are able to develop into cells exhibiting neural cell-like characteristics based on morphology, cell markers, and gene expressions. After expansion, Nanog overexpressed HMSCs differentiated into cells immunopositive for betaIII-tubulin and glial fibrillary acidic protein, lineage markers for neurons and astrocytes, respectively, under the influence of con-ditional media from differentiated human neural stem cells. This result indicates that the Nanog expression increased the ability of HMSCs to become a neural cell lineage. We further demonstrated that Nanog-overexpressed HMSCs were able to survive, migrate, and undergo neural cell-like differentiation after transplantation in vivo. This data offers an exciting prospect that peripheral adult stem cells can be modified and used to treat neurological diseases.
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