[Repair of acute spinal cord injury promoted by transplantation of olfactory ensheathing glia].

OBJECTIVES: To observe olfactory ensheathing glia (OEG) survival and repair in vivo for spinal cord injury after OEG transplantation.

METHODS: The OEG was cultured with the olfactory bulb of Wistar neonate rats. The spinal cords contusion was made in group A, B, and C with the New York University impactor, then complete transection was performed in the contusion area in group A. OEG labeled by Hoechst was transplanted in group A and B. In group C, DMEM were injected. In group D, laminectomies were done without cord contusion and transection. The functional recovery of the spinal cord injury [Basso, Beattie, Bresnahan (BBB) Locomotor Rating Scale scores] and changes of body weight were observed. The tissue sections were done 24 weeks postoperatively. HE staining, neurofibril (NF) immunohistochemical staining, and silver staining were performed respectively to observe the pathologic changes and axon regeneration. The survival of OEG labeled by Hoechst was observed under the fluorescence microscope.

RESULTS: Locomotive behaviour improved 4 weeks postoperatively. The BBB locomotion scores of group A and B were significantly higher than that of group C in all periods (from 4 weeks to 24 weeks) (P < 0.01). Sixteen weeks after operation, the BBB locomotion scores became stable and showed no change. HE staining showed that the area of spinal cord injury was disorder and the number of nerve cell was more in group A and B. In group C, there was the obvious cavum and few wring nerve fiber in the area of spinal cord injury. The nerve fibers innervated to the injuried area in group A and B were more than that of group C, but less than that of group D. A great number of OEG labeled by Hoechst were observed around spinal injuried area under fluorescence microscope. After operation, the body weight reduced in every group. The body weight of group D had recovered after 2 weeks and gradully increased. After 4 weeks, the body weight in group A, B, and C decreased to the minimum and were significantly less than that of group D (P < 0.01). After this, body weight in group A and B increased and was significantly more than that of group C (P < 0.05).

CONCLUSIONS: OEG transplantation can promote the axons regeneration and the recovery of locomotion function in experimental spinal cord injuries.