Behavioral assessment of cell transplantation after focal cerebral ischemia in rats.

We induced middle cerebral artery occlusion (MCAO) in rats using silicone-coated vascular embolus. We transplanted mouse embryonic stem (mES) cells after MCAO. Rats were tested behaviorally using motor and sensory function with neurological assessment. Functional effectiveness of the transplanted mES cells gradually improved the function of sensory and motor neurons. This study demonstrated that the transplanted cells have synaptic connection in the recipient brain. We suggest that stem cell transplantation can have a positive effect on behavioral recovery and reduction of infarct size in focal ischemic rats. Cell transplantation may induce certain functional recovery of the brain tissue by endogenous cell mediated effect. Our study suggests that intracerebrally injected mES cells survived and migrated into the infarct area from inoculation site and neuroglially differentiated in the ischemic brain area of adult rats. Therefore, mES cells may be a useful tool for the treatment in neurological diseases. In conclusion, cell transplantation therapy represents a novel approach that may enhance the efficacy and effectiveness of stem cell transplantation after ischemic stroke.