Background: Human bone marrow mesenchymal stem cells (hMSCs) can differentiate into several types of mesenchymal cells, including osteocytes, chondrocytes, and adipocytes, but can also differentiate into non-mesenchymal cells, such as neural cells, under appropriate experimental conditions. Until now, many protocols for inducing neuro-differentiation in MSCs in vitro have been reported. In this study, we induced differentiation into neural phenotype in the hMSCs population by new protocol. In this treatment, hMSCs could express neural markers more than other reports, associating with remarkable morphological modifications. 
Methods: The Bone marrow specimens were aspirated from the iliac crest of normal men. hMSCs were isolated and cultured in DMEM containing 15% FBS. Between 4-8 passages conversion of hMSCs into neurosphere-like structures and induction this cells to nerve precursors in the low-attachment plastic bacterial dishes with bFGF, EGF & RA were initiated. After seven days terminal neural differentiation was initiated by plating the cells on poly-L-ornithin and Laminin coated dishes. Cells were differentiated for 7-14 days. We used flowcytometry and immunocytochemistry analysis for assessment of specific neural stem cell markers in induced cells.
Results: Flowcytometery analysis showed that after induction, 90±2.52 percent of the cells will express neuronal marker Nestin and about 41±1 percent of the cells will express Tuj-1 and about 67±1.05 percent of the cells will express GFAP. Immunocytochemistry and morphologically modifications revealed the same results.
Conclusion: Results showed that hMSCs treatment with bFGF, EGF & RA the number of Tuj1 neurons. These data confirmed that hMSCs can exhibit neuronal differentiation potential in vitro, depending on the protocols of inducement.