Objective:To investigate the effect of SHU555A,a clinically approved iron nanoparticle,labeling on differentiation of bone marrow mesenchymal stem cells(BMSCs) into neurocyte-like cells in vitro.Methods:10 times dilution of 10μl,20μl,40μl and 80μl SHU555A were added to 2ml of culture medium containing rat BMSCs to obtain four experimental groups of SHU555A labeling of BMSCs with ferri ion concentrations of 14μg/ml,28μg/ml,56μg/ml and 112μg/ml,respectively.2ml of culture medium with rat BMSCs did not contain SHU555A served as control group.The BMSCs of all the groups were pre-induced by bFGF,and induced by DMSO/butylated hydroxyanisole(BHA) for six hours,subsequently reverse transcription polymerase chain reaction(RT-PCR) technique was employed to detect mRNA expression of nestin,neuronspecific analase(NSE) and glial fibrillary acid protein(GFAP).Western blot technique was used to detectprotein expression of nestin.Results:Quantitative-PCR revealed high mRNA expression of nestin,NSE and GFAP induced by DMSO/BHA in all the experimental groups,but the difference between the experimental groups and the control group was not significant(P>0.05).Western blot analysis demonstrated there was no statistically significant difference in nestin protein expression between the experimental groups and the control group(P>0.05).Conclusion:SHU555A labeling do not affect differentiation of rat BMSCs into neurocyte-like cells in vitro. Objective: To investigate the effect of SHU555A, a clinically approved iron nanoparticle, labeling on differentiation of bone marrow mesenchymal stem cells (BMSCs) into neurocyte-like cells in vitro. Methods: 10 times dilution of 10μl, 20μl, 40μl and 80μl SHU555A were added to 2 ml of culture medium containing rat BMSCs to obtain four experimental groups of SHU555A labeled of BMSCs with ferriion concentrations of 14 μg / ml, 28 μg / ml, 56 μg / ml and 112 μg / ml, respectively.2 ml of culture medium with rat BMSCs did not containing SHU555A served as control group. The BMSCs of all the groups were pre-induced by bFGF, and induced by DMSO / butylated hydroxyanisole (BHA) for six hours, subsequently reverse transcription polymerase chain reaction (RT-PCR) technique was employed to detect mRNA expression of nestin, neuronspecific analase (NSE) and glial fibrillary acid protein (GFAP). Western blot technique was used to detect protein expression of nestin. Results: Quantitative-PCR revealed high mRNA expression of nestin , NSE and GFAP induced by DMSO / BHA in all the experimental groups, but the difference between the experimental groups and the control group was not significant (P> 0.05). Western blot analysis presented there was no statistically significant difference in nestin protein expression between the experimental groups and the control group (P> 0.05) .Conclusion: SHU555A labeling do not affect differentiation of rat BMSCs into neurocyte-like cells in vitro.