Abstract: Objective: To investigate the effect of transplantation of olfactory ensheathing cells (OECs) originating from the olfactory mucosa and nerve growth factor(NGF) to repair spinal cords. Methods: The olfactory mucosa was separated from the nasal septum of adult Wistar rats. The OECs were purified by different attachment time with other types of cells and Ara-c inhibition， and the nerve growth factor receptor P⁷⁵(P⁷⁵NGFR) immunohistochemistry. The spinal cord samples were hemisected and they were randomly divided into three groups: the control group (group A), the olfactory ensheathing cell group(group B), and the olfactory ensheathing cells and the nerve growth factor group(group C). The Basso, Beattie, and Bresnahan locomotor rating scale(BBB) was observed at 2, 4, 6 and 8 weeks. Histological changes, the axon regeneration and the survival of OECs were determined 8 weeks later by an electron microscope, hematoxylin and eosin(HE) and immunohistochemistry staining. Result: The BBB grade of groups B and C was significantly higher than that of group A at 2 weeks, and that of group C was significantly higher than that of groups A and B. Histology revealed that the regeneration of axons was significantly promoted in group C. Conclusion: Transplantation of OECs and NGF is great for spinal cord repairs, and the two have a significant synergistic effect.

Key words: Olfactory mucosa, Olfactory ensheathing cells, Nerve growth factor, Spinal cord injury