To prevent graft rejection [24]. Cyclosporine A (10 mg/kg), azathioprine sodium (2 mg/kg), methylprednisolone (2 mg/kg, tapered to 0.5 mg/kg), and ampicillin (50 to 100 mg/kg) were administered 1 day before transplantation and throughout the experiment (for 2 months or 4 months).MRITo visualize the grafted cells in vivo, part of the cells were labeled with poly-L-lysine-coated superparamagnetic ironoxide (PLL-SPIO) nanoparticles, and four animals grafted with labeled cells, and four animals injected with saline underwent magnetic resonance imaging (MRI). MR images were taken 5 days after SCI (that is, before transplantation), and 1, 4, and 8 weeks after transplantation (that is, 2, 5, and 9 weeks after SCI). In total, 5 ?105 SPC-01 cells labeled with PLL-SPIO nanoparticles were injected in the same way as described earlier. MR images were obtained with a 4.7-T spectrometer (Bruker BioSpin, Ettlingen, Germany) by using a homemade surface coil incorporated in an animal holder dedicated for spinal cord measurements. The rats were anesthetized by 1.5 to 2 isoflurane in air. The respiration of the animals was monitored during the MR measurements. The rats were examined on their backs. After initial pilot scans, which were used for proper geometry setting, a turbo-spin echo sequence was used for theAmemori et al. Stem Cell Research Therapy 2013, 4:68 http://stemcellres.com/content/4/3/Page 4 ofacquisition of five slices in a sagittal orientation. The sequence parameters were turbo factor, 16; repetition time, TR = 2,000 ms; effective echo time, TE = 69.9 msec; number of acquisitions, AC = 48; field of view, FOV = 5 ?3 cm; matrix size, MTX = 256 ?256; slice thickness, 0.75 mm.Functional analysisFor motor testing, hindlimb locomotor activity after SCI was assessed with the Basso, Beattie, and Bresnahan (BBB) test [25] (SCI and SPC-01, n = 20; SCI only, n = 16). The rats were placed on a floor within a circular enclosure. Their hindlimb joint movement, paw placement, weight support, forelimb-hindlimb coordination, and so on, were evaluated by using a 0 to 21-point scale. For sensitivity testing, hindpaw-withdrawal latency to noxious thermal stimuli was assessed with a Plantar Test apparatus (Ugo Basile, Comerio, Italy) (the same animals that underwent BBB testing). The animals were placed in a clear plastic chamber and acclimated for 10 minutes until becoming quiescent. The hindpaw received a heat stimulus through a glass plate. Nelfinavir (Mesylate) The withdrawal latencies were measured 5 times for each hindpaw at 5-minute intervals. The motor function of the hindlimbs was also examined with the walking-beam PubMed ID:https://www.ncbi.nlm.nih.gov/pubmed/16989806 test (SCI and SPC-01, n = 8; SCI only, n = 8). The apparatus consisted of a 3.4-cm-wide and 140-cm-long wooden rectangular beam. A goal box was placed at one end. The central 1 m of the beam was used to evaluate the walking distance. The latency and the trajectory to traverse the beam were recorded with a video-tracking system (TSE-Systems Inc., Bad Homburg, Germany) for a maximum of 60 seconds. After pretraining, two trials were given each day for 3 consecutive days. The animals were examined before surgery and every week from the second week after the injection of SPC-01 cells or saline. A 0 to 7-point scale modified from Goldstein [26] was used to evaluate the locomotor function. The average of five values was used for statistical evaluation. The data are expressed as mean ?SEM. All data were compared between the sham-operated group and the transplanted.