Magnetic Resonance Imaging Detects Differences in Migration Between Primary and Immortalized Neural Stem Cells

Abstract

Rationale and Objectives-The study was performed to evaluate the effect of MRI contrast agent (super paramagnetic iron oxide (SPIO)) on differentiation and migration of primary murine neural stem cells (NSCs) in comparison to a neural stem cell line (C17.2). Since detection of labeled cells depends on the concentration of SPIO particles per imaging voxel, the study was performed at various concentrations of SPIO particles to determine the concentration that could be used for in vivo detection of small clusters of grafted cells.Materials and Methods-Murine primary NSCs or C17.2 cells were labeled with different concentrations of SPIO particles (0, 25, 100 and 250 μg Fe/ml) and in vitro assays were performed to assess cell differentiation. In vivo MRI was performed seven weeks after neonatal transplantation of labeled cells to evaluate the difference in migration capability of the two cell populations.Results-Both the primary NSC's and the C17.2 cells differentiated to similar number of neurons (Map2ab positive cells). Similar patterns of engraftment of C17. 2 cells were seen in transplanted mice regardless of the SPIO concentration used. In vivo MRI detection of grafted primary and C17.2 cells was only possible when cells were incubated with 100 μg/ml or higher concentration of SPIO. Extensive migration of C17.2 cells throughout the brain was observed, while the migration of the primary NSCs was more restricted.Conclusion-Engraftment of primary NSC's can be detected non-invasively by in vivo MRI and the presence of SPIO particles do not affect the viability, differentiation or engraftment pattern of the donor cells.

Post-Transcriptional Regulation of Osteoblastic Platelet-Derived Growth Factor Receptor-Alpha Expression by Co-Cultured Primary Endothelial Cells

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The Use of Cellular Magnetic Resonance Imaging to Track the Fate of Iron-Labeled Multipotent Stromal Cells after Direct Transplantation in a Mouse Model of Spinal Cord Injury

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High-Resolution Magnetic Resonance Microscopy and Diffusion Tensor Imaging to Assess Brain Structural Abnormalities in the Murine Mucopolysaccharidosis VII Model

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