【摘要】 目的　探讨新型的病毒载体 (HSV Amplicon)介导的神经营养因子 3(NT 3)和胶质细胞衍生的神经营养因子 (GDNF)共同表达 ,对耳蜗螺旋神经节细胞 (SGNC)的保护作用。方法　构建能够在独自的转录控制条件下 ,同时表达NT 3和GDNF的HSV Amplicon重组体 (HSVnt 3myc/gdnf)。包装后 ,转导体外培养的内耳细胞 (MOI =1) ,4 8h后分别测定培养基中NT 3和GDNF的含量。建立顺铂 (DDP)致聋的小鼠动物模型 ,2 4只实验小鼠被分成 3组 ,经鼠尾静脉隔日注射DDP两次 ,8mg/kg ,4 8h后再分别经圆窗将 10 μlHSVnt 3myc/ gdnf、HSVnt 3myc/lac和HSVlac病毒悬液注入鼓阶 ,饲养 4周后 ,取出耳蜗 ,采用NIH软件分析系统 ,定量分析耳蜗内SGNC的总数。结果　ELISA显示HSVnt 3myc/gdnf转导的内耳细胞培养基中 ,NT 3的含量达 11 4 4 μg/ml,而GDNF的含量达 1 79ng/ml,与对照组比较 ,差异有显著意义 (P <0 0 1)。在DDP致聋的小鼠模型中 ,定向转染HSVnt 3myc/ gdnf、HSVnt 3myc/lac和HSVlac的耳蜗平均SGNC存活率分别为 88%、77%和2 2 % ,各组间差异有显著意义 (P <0 0 1)。结论　HSV Amplicon介导的NT 3/GDNF共同表达 ,可以刺激SGNC分泌NT 3和GDNF ,有效拮抗耳毒性药物所致的SGNC损伤 ,提高SGNC的残留数量 ,促进SGNC突起的再生。更多还原

【Abstract】 Objective To investigate the attenuation of cisplatin induced toxicity in the spiral ganglion neuron (SGNC) by the localized expression of the neurotrophin 3 (NT 3) and glial cell line derived nerutrophic factor (GDNF) via HSV Amplicon Methods We constructed the HSV Amplicon vectors, which could express the NT 3 and GDNF under separate transcriptional control Helper virus free amplicon stocks were assessed in vitro for their capacity in the cultured inner ear cells The ELISA was used to detect the production of NT 3 and GDNF Three groups of mice were injected with cisplatin (8 mg/kg), followed by instillation of HSVnt 3myc/gdnf, HSVnt 3myc/lac or HSVlac The numbers of SGNC were analyzed 4 weeks later Results The HSVnt 3myc/gdnf transduction resulted in production of NT 3 up to 11 44 μg/ml and GDNF up to 1 79 ng/ml in cultured medium over 48 h There were significant differences among three groups ( P <0 01) Cochleae transduced with HSVnt 3myc/gdnf and HSVnt 3myc/lac harbored from the mice had greater number of surviving SGNC The ratio of SGNC survival (%) in HSVnt 3myc/gdnf, HSVnt 3myc/lac and HSVlac was 88%, 77% and 22%, respectively Conclusion The transduction of NT 3/ GDNF by HSV Amplicon greatly attenuated SGNC the cisplatin induced ototoxicity in mice更多还原