Biological Characteristics And MRI Imaging Of Rabbit Bone Marrow Mesenchymal Stem Cells(BMSCs)Labeled By Superparamagnetic Iron Oxide Nanomaterials(SPIO)

ObjectiveCulturing and amplifying of rabbit BMSCs by using red blood cells lysis and adherent culture in vitro. Labeling rabbit bone mesenchymal stem cells (BMSCs) with superparamagnetic iron oxide nanomaterials (SPIO) in vitro. Exploring growth activity and osteogenic and adipogenic differentiation capacity of rabbit BMSCs labeled by SPIO;Exploring MRI imaging features of labeled rabbit BMSCs in vitro. To provide the basic experiment of magnetic resonance imaging (MRI) tracking stem cells transplantated in the treatment; To substantiated convictively the efficacy of treating diseases with BMSCs.Methods1 To culture and expand of rabbit BMSCs by using red blood cells lysis and adherent culture in vitro. To substantiate BMSCs through morphology, biological function and flow cytometric analysis.2 To label rabbit BMSCs with SPIO of different concentration (100ug/ml, 50ug/ml,25ug/ml,12.5 ug/ml) and PLL (0.75 ug/ml). To analyze the labelling rate of BMSCs labeled with SPIO by prussian blue staining. To analyze bioactive influence of BMSCs labeled witn SPIO by measuring MTT metablism. To find out a more safe and more effective appropriate labeling concentration of SPIO. 3 To choosing SPIO with most appropriate labeling concentration to label rabbit BMSCs.To analyze cells histologic of labeled cells by transmission electron microscope. To analyze osteogenic and adipogenic differentiation capacity of labeled rabbit BMSCs and nonlabeled rabbit BMSCs.To identify the osteogenic differentiation capacity by alkaline phosphatase assay and alizarin red vital staining. and to identify the adipogenic differentiation capacity by oil red O dyeing.4 To observe the MRI imaging features of rabbit BMSCs labeled SPIO with most appropriate labeling concentration by MRI scanning.Results1 we can detect a great quantity of adherent cells with great activity and generation capacity by inverted phase contrast microscope. Flow cytometric analysis results show that the cultured cells witn high level expression of CD29,CD44,CD90 and low level expression of CD34,CD45. To confirm the cultured cells is rabbit BMSCs.2 SPIO with different concentrations can lebel rabbit BMSCs well. Prussian blue staining show that SPIO in the BMSCs' cytoplasm. And the higher the labeling concentration of SPIO.the higher labelling rate. The labelling rate for SPIO (25 ug/mL 48h)labeling cells is near 100%. MTT show that the concentration of SPIO less than 50 ug/ml can not influence growth activity of labeled rabbit BMSCs obviously.3 Transmission electron microscope detection shows that SPIO in the BMSCs' cytoplasm after BMSCs lebeled by SPIO(25ug/ml).The labeled rabbit BMSCs and nonlabeled rabbit BMSCs have the same osteogenic and adipogenic differentiation capacity.4 MRI scanning can observe obviously reduced signal of cells labeled by SPIO(25ug/ml) in T2*WI sequence. Conclusions1 Using red blood cells lysis and adherent culture can culture and expand of rabbit BMSCs in vitro, Confirm that the cultured cells are rabbit BMSCs.2 SPIO can label rabbit BMSCs.and can not influence growth activity of labeled rabbit BMSCs obviously.There is more efficacy and safety of labeled rabbit BMSCs with SPIO(25ug/ml) and PLL(0.75ug/ml).It can not influence osteogenic and adipogenic differentiation capacity of labeled rabbit BMSCs obviously.3 MRI scanning can observe obviously the labeled BMSCs with SPIO in T2*WI sequence.To provide the basic experiment for the next MRI tracking stem cells transplantated research.