内耳转基因表达的实验研究

Experimental study of transgenic expression in inner ear

目的 了解内耳转基因表达的可行性。方法 将人复制缺陷重组腺病毒基因(Adenoviruses ,Ad ,含大肠杆菌 β 半乳糖苷酶基因LacZ基因 ,Ad5 LacZ)经豚鼠耳蜗蜗窗接种到鼓阶外淋巴后 ,观察在不同时间、不同内耳组织中LacZ基因的表达 (X Gal染色 )及Ad对豚鼠声反应 (听性脑干反应 )、听毛细胞 (扫描电镜 )的影响。结果 Ad介导的LacZ基因在内耳组织中的表达至少可持续 4周 ,其中在螺旋神经节细胞表达稳定 ,Corti器、前庭囊斑、壶腹嵴的毛细胞等也有较强的表达。Ad未对豚鼠声反应 (≤ 80 0 0Hz)造成明显的损伤 ,除耳蜗底回外 ,其余各回未见明显的毛细胞缺失。结论 腺病毒载体可成功地将LacZ基因转导致豚鼠内耳组织中 ,并且未对豚鼠声反应 (低、中频 )及听毛细胞造成明显损伤 ,这对未来的内耳基因治疗研究可能具有重要的参考价值。

Objective To evaluate the feasibility of transgenic expression in inner ear Methods After Ad5 LacZ (replication deficient recombinant human adenovirus, containing Escherichia coli β galactosidase gene) was injected into the perilymphatic fluid through the round windows of guinea pigs, and the expression of LacZ(galactosidase staining) in different cochlear tissues and the hearing(ABR) and the auditory hair cell(scanning electron microscope) were observed in different time Results The expression of LacZ mediated by Ad in guinea pig cochlea could last 4 weeks at least, and the expression was most stable in spiral ganglion cells, while it was also found in hair cells of the organ of Corti, vestibular maculas and ampulla Ad didn′t do great harm to the hearing(≤8 000 Hz), there were not significant loss of the auditory hair cells except the sparely loss of outer hair cells at the basal turn of cochlea Conclusion Ad can successfully transport LacZ into inner ear tissue of guinea pig,and it does not do great harm to the hearing and the auditory hair cells of guinea pigs, this may have important value for gene therapy of inner ear in the future