Objective
To define the migration and differentiation of adult human mesenchymal stem cells (hMSCs) derived from bone marrow, and their effect on neurobehavioral and cognitive improvements, after traumatic brain injury (TBI) in rats. Method: Two days after TBI, 1×106 hMSCs were injected into the corpus callosum of fifteen rats, on the contralateral side of TBI. Eleven rats received sham-operation as a control group. Neurobehavioral and Barnes maze tests, and magnetic resonance spectroscopy (MRS) were performed on days 1 and 28 after TBI. Immunohistochemical staining was performed to evaluate distribution and differentiation of hMSCs on day 56. Results: After 28 days, scores on the neurobehavioral test, Barnes maze test, and magnetic resonance spectroscopy (MRS) were higher than on day 1 in both the stem-cell and control groups, but there were no between-group differences. On day 56, injected hMSCs stained positively with MAB- 1281 were distributed in ipsilateral corpus callosum, lesion boundary zone, parietal cortex, and thalamic area around the lateral ventricle. Conclusion: hMSCs injected to the contralateral side of TBI survive and migrate to various areas of the ipsilateral hemisphere. We observed no neurobehavioral or cognitive improvements in test animals, indicating the need to adjust experimental methodologies including the development of appropriate tests to evaluate neurobehavioral and cognitive functions of rats. (J Korean Acad Rehab Med 2009; 33: 520-526)
