Page 49 - Cellular Imaging in Regenerative Medicine, Cancer and Osteoarthritis

rectangle of the grid. The cells were allowed to sediment and adhere to the bottom of the well before additional medium was added. Directly before each MRI scan, the medium was replaced with fresh medium containing Gd-DTPA (Magnevist, Bayer Schering Pharma AG, Berlin, Germany) at a v/v ratio of 1:200 to provide enhanced SNR and contrast-to-noise (CNR) ratios using T1-weighted protocols to decrease imaging time. The grid was filled with ultrasound gel, to provide contrast in MR images. Each sample was placed over a single-loop solenoid coil with an inner diameter of 1.0 cm (Flick Engineering Solutions, The Netherlands). The distance between the loop and the cell monolayer was 1.3 mm, which was the thickness of the bottom of the plate. The scan protocol was limited to a three-plane localizer followed by a high-resolution 3DT1-weighted scan. The following scan parameters were used: 3D-SPGR sequence with TR/TE 41.1/10.5 ms, and a flip angle (a) of 508 with a resolution of 38 x 38 mm x 100 mm and a FOV of 2 x 2 cm and an imaging time of 13 min.
5.7. Data analysis and statistics
Data are expressed as mean ± SD from triplicate samples in two or three repeated experiments. Statistical analysis of differences between data sets was performed by ANOVA (Graphpad Prism 4.0, GraphPad Software, La Jolla, CA, USA) followed by a post hoc test (Newman-Keuls Multiple Comparison Test). A p-value of <0.05 was considered significant.
Acknowledgments
This paper has been written in part through support from ENCITE – funded by the European Community under the 7th Framework Program.
Influence of SPIO cell labeling protocol
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