A Study on in-vitro Transdifferentiation of Rat Bone Marrow Stromal Cells into Neuroepithelial-Like Cells

Background: Bone marrow stem cells (BMSCs) are a rich source of stem cells and may represent a valid alternative to neural or embryonic stem cells by replacing the autologous damaged tissues in neurodegenerative diseases. In this study, we attempted to devise a protocol for the induction of BMSCs into neuroepithelial-like cells (NELCs). Methods: Rat BMSCs were isolated from the long bones of adult Sprague–Dawley rats. Their purity in the 4th passage was evaluated with fibronectin by immunocytochemistry, and the stemness marker Oct-4 was assessed by RT-PCR technique. The cells were expanded and induced in the induction stage. The BMSCs were incubated with either β-mercaptoethanol (βME) (1 mM), dimethyl sulfoxide (DMSO) (2%) or biotylated hydroxyanisol or butylated hydroxyanisol (BHA) (200 μM) in α-MEM medium without fetal bovine serum (FBS). They were washed with phosphate buffer saline (PBS) and proceeded to the 2nd phase of induction, where the induction medium was changed with α-MEM and 15% FBS containing all-trans retinoic acid (RA) (1 μM) (for 3 days). Then, the expression of the markers was assessed with GFAP, nestin and neurofilament 68 antibodies, respectively and the expression of Oct-4 and NeuroD was evaluated by RT-PCR. Results: The purity of the BMSCs at the 4th passage was more than 92%. The mRNA of Oct-4 was expressed in these cells. Induction of BMSCs by DMSO-RA could differentiate NELCs significantly more than βME-RA and BHA-RA. The transdifferentiation of NELCs was evaluated by nestin antibody and NeuroD mRNA expression; later markers expressed very low detectable level in BMSCs. But the differentiation of BMSCs into astrocytes was less in all of the experiment groups that is estimated GFAP antibody. Conclusion: The application of DMSO-RA can transdifferentiate BMSCs into NELCs in- vitro.