Abstract:

BACKGROUND: Some investigators used superparamagnetic iron oxide to label bone marrow mesenchymal stem cells (BMSCs). Magnetic resonance imaging was used to conduct primary living tracing of labeled cells in the liver and kidney following transplantation. However, there are a few reports addressing survival, proliferation and differentiation of superparamagnetic iron oxide-labeled BMSCs.
OBJECTIVE: To research whether there is any effect on cellular viability, proliferation and differentiation into neural cells of BMSCs following labeling with superparamagnetic iron oxide particles. 
METHODS: Superparamagnetic iron oxide was used to label rat BMSCs, and Prussian blue staining was used to identify labeling index. Trypan blue staining was employed to detect cell vitality. MTT assay was utilized to detect proliferation activity of labeled stem cells. Labeled stem cells were induced to differentiate into neural cells in vitro with 1 mmol/L β mercaptoethanol (BME) and serum-free DMEM. Immunohistochemistry was used to lay induced cells, and then Prussian blue staining was employed to identify the iron particles in neural cells again. 
RESULTS AND CONCLUSION: The stem cell labeling rate with Prussian blue staining was nearly 100%. The cell vitality rate with Trypan blue staining was 97%. MTT method detected that there was no significant difference for proliferation activity between labeled stem cells and those not labeled (P > 0.05). Majority of BMSCs differentiated into neuron-like cells after inducing by BME. Immunohistochemistry was positive. Prussian blue staining again showed that iron particles were in the nerve cell cytoplasm. These suggested that there is no effect on survival, proliferation and differentiation into neural cells of stem cells after it is labeled by superparamagnetic iron oxide.