Abstract:

BACKGROUND: Studies show that the microencapsulated heterogeneous olfactory bulb cells can reduce the immunological rejection and improve the functional recovery of spinal cord injury. However, the mechanism is unclear.
OBJECTIVE: To investigate the effects of the xenotransplantation of microencapsulated olfactory bulb cells into rats on the expression and activity of nuclear factor-kappa B (NF-κB) after spinal cord injury.
METHODS: Rabbits were used to prepare the heterogeneous olfactory bulb cell suspension. Sprague Dawley rats were randomly divided into four groups: the sham operation group, the microcapsule group, the cell group and the simple injury group. The rats in the later three groups were prepared for spinal cord hemisection model and transplanted with gelatin sponge sticking 10 μL microencapsulated olfactory bulb cell suspension, 10 μL microencapsulated olfactory bulb cell suspension, and 10 μL physiological saline respectively. The pathological changes of spinal tissues were observed by haematoxylin-eosin staining, and the expressions of NF-κB were observed by immunohistochemical staining. 
RESULTS AND CONCLUSION: The expressions of NF-κB in the cytoplasm and cytoblast of neurons were increased in rats after spinal cord injury. The expression level reached a peak at 24 hours, gradually decreased after 3 days, and returned to the normal level after 7 days. The NF-κB+ cells in the microcapsule group were obviously fewer than that in the cell and simple injury groups (P < 0.05). The xenotransplantation of microencapsulated olfactory bulb cells can inhibit the expression and activity of NF-κB to mitigate the NF-κB modified inflammatory reaction after spinal cord injury.