Effect of free NgR-modified bone marrow stromal cell transplantation on axon regeneration after spinal cord injury / 中华物理医学与康复杂志

ABSTRACT

Objective To evaluate the effect of free NgR-modified bone marrow stromal cell (BMSC) transplantation on axon regeneration in rats after spinal cord injury. Methods Genes encoding free NgR protein were cloned and transduced into BMSCs at passage 3 using a lentivirus vector.Indirect immunofluorescence was used to detect the expression of free NgR protein.Meanwhile a spinal cord contusion model was established in 36 adult Sprague-Dawley rats at the T10 segment.The rats were then divided randomly into an experimental group and a control group.NgR + BMSCs were transplanted into the injured site 1 week post-trauma in the experimental group.BMSCs were also transplanted at the same time into the control group.Expression of free NgR at the injury site was detected by immunohistochemical staining at 1 week post-transplantation.The functional recovery of both groups was evaluated at 4 and 6 weeks post-transplantation.Longitudinal sections of the spinal cord were studied for axon regeneration using horseradish peroxidase staining. Results Expression of free NgR was found in the cell plasma of BMSCs by indirect immunofluorescence post-transfection.Positive immunohistochemical staining for NgR was found at the transplant site in the experimental group 1 week post-transplantation.Better axon plasticity could be observed in the experimental group.The Basso-Beattie-Bresnahan scoring of the experimental group was significantly higher than that of the controls at both observation times. Conclusions Free NgR-modified BMSCs can prompt injured axons to regenerate and thus to promote the recovery of neurological function.This might provide a new strategy to treat spinal cord injury.