Transplantation Of Bone Marrow Mesenchymal Stem Cells Promote Functional Recovery Of The Injured Rats Spinal Cord

PurposeIt was previously known that the central nervous system did not regenerate once it was injured, especially in the spinal cord of the mammalian animals. But in the 1980s, studies were reported that transplantation of peripheral nerves and fetal spinal cord could cause injured axons of spinal cord to regenerate. Such studies have showed that regeneration of the injured spinal cord might really be possible. Bone marrow mensenchymal stem cells (MSCs) have already become a new resource of cell replacement therapies with the capability under specific conditions to differentiate into other cell types such as osteoblasts, adipocytes, chondrocytes as well as neuron -like cells. Also, MSCs are easily obtained and rapidly expansion in vitro.Transplantation of MSCs into the spinal cord after a contusion injury was also reported to enhance functional recovery based on standardized assessments. MSCs were directly injected into the spinal cord immediately after injury or after cocultured with neurosphere cells. Treated animals generally showed better performance of gait than control animals. MSCs at the center of the injury appeared to pull the surrounding host tissues towards the center, preventing the formation of cavities. However, at present, there isn't enough evidence to show that whether MSCs can promote recovery of conduction function in the injured spinal cord or not. Therefore, we established the animal model of spinal cord half -transection injury, and then investigated the role that MSCs played in conduction recovery of the injured spinal cord.Methods1. Preparations of rat MSCsa. Under sterile conditions collect bone marrow cells from the tibias and femurs of the rats as primary culture.b. Immunocytochemistry identification of the expression of CD45 and CD90 when subculture.2. MSCs are prelabeled with BrdU in vitro before transplantation.3. Transplantation of MSCsa. Preparations of rats model of spinal cord half - transection injuryb. inject MSCs into the spinal cord injury site immediately after injury in experimental groups, but PBS are injected in control groups.4. outcome assessmentsa. Functional evaluation using the open — field BBB scoring systemb. Fixation of the rats spinal cord by heart perfusionc. Immunohistochemistry identification of BrdU to show whether MSCs survive or not after transplantationd. HRP antitracting 48 hours before collect spinal cord samplee. Examination of the formation of neuronal circuits by HRP stainingf. Examination of the reconstruction of neuronal circuits by CSEPg. Statistics analysisResults1. Immunocytochemistry showed that MSCs express CD45 ( - ) , CD90(+).2. Treated rats generally showed better functional recovery than control ratsafter operation.3. BrdU positive cells could be found in the spinal cord injury site one" week after transplantation.4. Two months after transplantation, HRP positive cells could be found at...