Abstract
Several experimental and clinical studies have reported intravenous transplantation of mesenchymal stem cells (MSCs) derived from bone marrow ameliorates functional deficits in cerebral infarction. However, functional recovery is not always correlated with lesion volume assessed by T2 weighted image in MRI. In this study, we reported the relationship between fMRI patterns and functional recovery of ischemic stroke model rats transplanted intravenously MSCs. In medium infused group, electrical stimulation of the left forepaw elicited a unilateral (right cortex) activated signal detected by fMRI in the infarcted somatosensory cortex. In the MSCs infused group, their motor function were significantly improved compared to the medium infused group, and two fMRI patterns were observed: unilateral and bilateral activation of sensorimotor cortex. The bilateral activated pattern in the MSCs group showed the greatest functional recovery in spite of the same lesion volume compared to unilateral activated pattern. These results suggest that the detection of a bilateral signal in sensorimotor cortex by fMRI was more predictive of improved functional outcome than lesion volume alone. Further evaluation of these results in the ongoing randomize clinical trial (phase 3) using auto serum-expanded autologous MSCs in the stroke patients is warranted.
