Effect of olfactory ensheathing cell transplantation on myelin repair and motor function in a rat model of experimental allergic encephalomyelitis

摘要

BACKGROUND: Olfactory ensheathing cell transplantation can activate axonal regeneration and enhance myelin repair, which are beneficial for treating demyelinating diseases.OBJECTIVE: To explore the effects of olfactory ensheathing cell transplantation on myelin repair, synaptophysin expression, and motor function in a rat model of experimental allergic encephalomyelitis.DESIGN, TIME AND SETTING: A randomized, controlled experiment was performed at the Laboratory of Provincial Hospital affiliated to Shandong University between August 2006 and September 2007.MATERIALS: Dibenzylamine (Hoechst 33342), luxol fast blue, and rabbit anti-rat synaptophysin antibody were provided by Sigma, USA.METHODS: Olfactory ensheathing cells extracted from neonatal Wistar rats were cultured for 10-14 days and labeled with dibenzylamine. Spinal cord extracted from a healthy guinea pig was homogenized and equally mixed with complete Freund's adjuvant; thereafter, the mixture was intracutaneously injected into two posterior voix pedis of healthy male Wistar rats to establish models of experimental allergic encephalomyelitis. Rats were randomly divided into a control encephalomyelitis group and an olfactory ensheathing cell transplantation group, 36 rats in each group. Physiological saline (2μL) or an olfactory ensheathing cell suspension (2μL) was separately injected along lateral cerebral ventricle at day 7 post-model induction.MAIN OUTCOME MEASURES: The migration and distribution of olfactory ensheathing cells were observed under fluorescence microscopy; myelin repair was detected using hematoxylin-eosin staining and luxol fast blue staining; synaptophysin expression was measured using immunohistochemical staining; motor function was evaluated using a motor function scale.RESULTS: Olfactory ensheathing cells could survive in vivo and migrate to the distal end of the transplant focus and spinal cord, and survived 21 days. Hematoxylin-eosin staining and luxol fast blue staining indicated that myelin in the transplantation group was intact, and the inflammatory focus gradually disappeared. Transplantation increased synaptophysin expression (P<0.05versus control) and motor function (P<0.05).CONCLUSION: Olfactory ensheathing cell transplantation can promote myelin repair, increase synaptophysin protein expression, and ameliorate motor function in a rat model of experimental allergic encephalomyelitis.