| PurposeWe studied the migration of bone marrow stromal cells(BMSCs) labeled with superparamagnetic iron oxide(SPIO) grafted in intracerenral hemorrhage(ICH) rats brain by magnetic resonance imaging(MRI), and observed the effects on the recovery of motor function of the rats.Methods1. Rat bone marrow-derived mesenchymal stem cells were isolated and cultured by all-adherent bone marrow. Cell morphology changes was observed under inverted phase contrast microscope in the cultivation process. And cell-surface antigens(CD34, CD44, CD45 and CD105) of the cells were identified by immunocytochemical method. The cells can be used in the later experiments after six generations. 2. BMSCs were labeled with different concentrations of SPIO, and then the cell viability was detected by MTT assay in the unlabeled and labeled BMSCs group. Both the cells unlabeled and labeled were differentiated into neuron-like cells by the induction of bFGF, DMSO and BHA, and then the mRNA expression of Nestin, NSE, and GFAP were detected in each group cells after differentiation Using RT-PCR.3. Autologous blood injection was used to establish a rat model of intracerebral hemorrhage(ICH). There were five groups (N=8):group 1, normal control with BMSCs labeled by SPIO transplanted; group 2, model control with BMSCs labeled by SPIO transplanted; group 3, ICH rats with BMSCs labeled by SPIO transplanted; group 4, ICH rats with BMSCs unlabeled by SPIO transplanted; group 5, negative control with only medium.4. Experimental animals in each group scored 3 days,1 week,2 weeks and 4 weeks after transplantation using Longa method. MRI examination were undergone at the same time points. After MRI examination, brain tissues were taken for frozen section prussian blue staining to observe the distribution of transplanted cells in the brain.Results1. The cells morphology showed a more uniform distribution and fiber-like appearance. And immunocytochemistry showed that cells expressed CD44, CD105, and not express CD34, CD45.2. The control group as well as different concentrations of labeled cells group had no significant differences in the optical density measured by MTT method (F=0.621, P=0.652>0.05). The mRNA expression of Nestin, NSE and GFAP of each group showed no significant differences after neural induction detected by RT-PCR. 3. The intracerebral hemorrhage model and control group was significantly different by Longa score. After MRI examination, the model group rats showed patchy high signal on T1WI, and low signal hemorrhage on T2WI and SWI sequences in the right basal ganglia for one day.4. Neurological function score showed that group A, B, C, D and E between subjects had statistically significant at different time(F=55.02,P=0<0.05). Besides, group C and D within-subjects had statistically significant of 3 day,1 week,2 weeks and 4 weeks after transplantation(F=121.032, P=0.000<0.05).5. On the MRI images undergone at 3 day,1 week,2 weeks and 4weeks after transplantation, the SPIO labeled BMSCs showed low signle intensity on all of the sequences. And the low signle extended to the hemorrhage side, and even migrate across the midline to the opposite periphery of the hemorrhage lesion after 4 weeks.Conclusions1. SPIO markers had no significant effect on the biological activity, growth and differentiation of BMSCs.2. BMSCs transplantation can promote the recovery of function in intracerebral hemorrhage rats. And SPIO had no effect to limit the role of BMSCs in the recovery of function in intracerebral hemorrhage rats.3. These studies demonstrate that magnetic resonance imaging of grafted bone marrow stromal cells labeled with superparamagnetic iron oxide is a useful method for evaluating their migration and fate in CNS. |
PDF Full Text Request