Objective      To determine the effect of neural differentiation of bone marrow mesenchymal stem cells (MSCs) on the expression of the reporter gene

ferritin heavy chain 1 (FTH1)

and to explore the feasibility of visualizing the neural differentiated cells with FTH1 for magnetic resonance reporter gene imaging. Methods      The reporter gene FTH1 was transfected into the MSCs by using a lentivirus system. Then the MSCs carrying FTH1 (MSCs-FTH1) were induced into a neural-direction differentiation with all-trans retinoic acid and modified neural induction media. The dynamic expression of the FTH1 in MSCs-FTH1 and neurons-FTH1 (the neural differentiated cells) were assessed by Western blotting. MR imaging was performed to detect the changes of T2WI signal intensity of both cells. Prussian blue staining and transmission electron microscopy were used to determine the iron accumulation in the cells. Results       The MSCs-FTH1 successfully differentiated into neuron-like cells (Neurons-FTH1). The expression of FTH1 was detected in both MSCs-FTH1 and Neurons-FTH1 by Western blotting. Under the cultural condition of 500 μmol/L of ferric ammonium citrate

remarkable decrease of T2WI signal was seen in the both cells. Prussian blue staining and transmission electron microscopy verified the extensive iron accumulation in MSCs-FTH1 and Neurons-FTH1. Conclusion       The neural differentiation of MSCs has no impact on the expression of FTH1

therefore MRI based on the reporter gene FTH1 can be used in the detection of neural differentiated cells.