A comparison of autologous and allogenic bone marrow-derived mesenchymal stem cell transplantation in canine spinal cord injury.

The purpose of this study is to compare the therapeutic effects between autologous and allogenic bone-marrow-derived mesenchymal stem cell (MSC) transplantation in experimentally-induced spinal cord injury (SCI) of dogs. Thirty adult Beagle dogs (control group=10, autologous group=10, and allogenic group=10) were used in this study. Prelabeled MSCs were intrathecally transplanted through the lumbar spinal cord into the injured lesion at a density of 1 x 10(7) cells 7 days after SCI. Neurological signs of dogs in both autologous and allogenic groups were improved in their pelvic limbs after SCI compared with those in control group. Both autologous and allogenic groups showed significantly higher the Olby scores than control group (p<0.05). This finding was consistent with results of MRI and histopathological examination in both groups. Immunofluorescence analysis revealed that prelabeled autologous and allogenic MSCs were detected in the injured lesions both at 1 and 4 weeks after transplantation. However, the distribution ratio of MSCs on the injured lesion in allogenic group was significantly decreased at 4 weeks after transplantation relatively to at 1 week after transplantation. The mRNA expression for neurotrophic factors in both allogenic and autologous groups was significantly higher than that in control groups (p<0.05). Even though autologous MSC transplantation showed more beneficial effect than that of allogenic MSC transplantation, transplantation of allogenic MSCs also improved functional recovery following SCI. This study demonstrates that both autologous and allogenic MSC transplantation could be clinically useful therapeutic approaches for treating SCI.