腺病毒携带EGFP基因经完整圆窗膜转导豚鼠耳蜗的实验研究

目的研究腺病毒携带目的基因经完整圆窗膜途径耳蜗转导的可行性及安全性，为内耳基因治疗提供实验基础和理论依据。方法20只白色红目豚鼠，术前及术后分别行听性脑干反应（ABR）检查。实验组（12只）以重组腺病毒携带的增强型绿色荧光蛋白基因（enhancedgreenfluorescentprotein，EGFP），对照组（8只）以人工外淋巴液注入豚鼠圆窗龛内。分别于术后5天、14天取双侧耳蜗标本做基底膜铺片，耳蜗冰冻切片观察。结果于圆窗龛内注入腺病毒携带目的基因的转导方法对听力无明显影响。转染耳蜗及对侧耳蜗内目的基因呈广泛表达。5天组表达产物最高，14天组逐渐降低。对照组耳蜗未见EPFP表达。结论于圆窗龛内注入腺病毒携带目的基因转导的方法对耳蜗无明显毒害作用，且能够将目的基因成功转导至双侧耳蜗组织并广泛表达。     

耳后入路圆窗膜显微注射小鼠耳蜗基因转染新途径的研究

目的研究腺病毒携带目的基因经小鼠耳后人路圆窗膜显微注射途径耳蜗转导的可行性,为以小鼠作为动物模型的内耳基因治疗提供实验基础和解剖学依据。方法12只C57BL／6J小鼠分为2组,实验组（8只）以重组腺病毒携带的增强型绿色荧光蛋白基因（enhanced green fluorescent protein,EGFP）、对照组（4只）以人工外淋巴液经耳后入路圆窗膜显微注射注入耳蜗内。分别于术后5、14天取双侧耳蜗标本做基底膜铺片,在激光共聚焦显微镜下观察GFP表达。结果术后动物存活10只（每组死亡1只）。实验组转染后耳蜗底回基底膜及螺旋神经节上目的基因有表达,14天组强于5天组。对照组耳蜗未见荧光表达。结论耳后入路操作简单、损伤小、易于暴露圆窗龛。耳后入路圆窗膜显微注射腺病毒携带目的基因转导的方法能够将目的基因成功转导至耳蜗组织并表达。     

听力学

20030451腺病毒携带GFP在豚鼠耳蜗基因转导的形态结构与功能改变/王晓侠…//西安医科大学学报一2002,23(2)一121一124,188 目的:带有绿色荧光蛋白(GFP)基因的腺病毒注人豚鼠耳蜗后,观察不同时间段GFP基因的表达和分布情况及手术操作对听力的影响,为内耳基因治疗提供理论依据。方法:15只杂色豚鼠术前及术后行听性脑干反应(ABR)和畸变产物耳声发射(DP()AE)检查,空白对照组经圆窗或底回钻孔注人人工外淋巴液。实验组注入带有GFP基因的腺病毒。分别于3、5、7和lod后取材,耳蜗标本经硝酸银染色后铺片。结果:腺病毒注人耳蜗后对听阂影响不…     

重组腺病毒构建及介导报告基因在豚鼠耳蜗中的表达

目的：带绿色荧光蛋白（GFP）基因的重组腺病毒,为利用重组腺病毒介导外源基因转导内耳提供依据。方法：通过细菌内同源重组方法构建携带有报告基因的重组腺病毒（Ad-GFP）,将重组腺病毒经耳蜗底回途径导入豚鼠耳蜗鼓阶外淋巴后,观察手术后不同时间GFP基因在豚鼠耳蜗内的表达、分布情况;检测手术前后听觉脑干诱发电位,观察手术和病毒对豚鼠听觉功能的影响。结果：构建的重组腺病毒经酶切电泳鉴定正确;豚鼠耳蜗底回途径导入腺病毒24 h后即有报告基因表达,3 d后最高,表达时间可持续2周以上;报告基因表达部位主要分布在血管纹、鼓阶外淋巴面的间皮细胞和耳蜗Corti器等部位;听觉脑干诱发电位（ABR）在各组动物手术前后无明显改变。结论：成功构建了携带GFP基因的重组腺病毒,通过该方法构建的腺病毒可以介导报告基因在豚鼠耳蜗中表达,并且对豚鼠听觉功能无明显影响,为内耳基因治疗提供了理论依据。     

Math1基因内耳导入径路的探索研究

目的研究腺病毒携带Math1-EGFP基因经完整圆窗膜途径及鼓阶打孔途径导入耳蜗后对听功能和转导效率的影响,为内耳基因治疗提供实验基础和理论依据。方法健康成年白色红目豚鼠40只,雌雄不限,体重250—300g。随机分成四组,完整圆窗膜组12只,鼓阶打孔组12只,各组分别设对照8只。实验组（24只）导入重组腺病毒携带的Math1基因及增强型绿色荧光蛋白基因（enhanced green fluorescent protein,EGFP）,对照组（16只）导入人工外淋巴液,所有动物均以左耳作为导入耳。术前及术后分别行听性脑干反应（ABR）检查。分别于术后5天、14天取双侧耳蜗标本做基底膜铺片观察基因表达情况。结果完整圆窗膜组导入耳ABR阈值,术后5天各频率与术前比较无显著性差异（P〉0．05）;鼓阶打孔组导入耳ABR阈值,术后5天在2kHz、4kHz与术前比较无差异（P〉0．05）,8kHz较术前增高（P〈0．05）,16kHz、20kHz较术前明显增高（P〈0．01）,术后14天在16kHz、20kHz较术后5天时明显好转（P〈0．01）,但较术前仍有增高（P〈0．05）。转导成功率鼓阶打孔组为91．6％,优于完整圆窗膜组的50％。两种转导途径对目的基因在耳蜗内的表达部位和表达时间没有显著影响。结论完整圆窗膜途径及鼓阶打孔途径在转导成功率及听功能保护方面各有优劣。完整圆窗膜途径因其对耳蜗的损伤极小,在临床应用方面具有更好的发展前景。     

Ad-GFP基因经半规管转导对豚鼠内耳形态和功能的影响

目的探讨经半规管途径转导豚鼠内耳基因的可行性,绿色荧光蛋白的表达及其对内耳形态和功能的影响.方法采用白色红目健康纯种豚鼠24只,将缺陷型腺病毒携带的绿色荧光蛋白基因5μl经显微手术自前半规管灌入豚鼠内耳,同法注入人工外淋巴液5μl作对照,另一组经圆窗膜注入5μl Ad-GFP基因,分别在手术后7、14、21、28d处死,0.5%硝酸银灌注耳蜗基底膜铺片显微镜观察内外毛细胞缺失,全耳蜗铺片荧光显微镜观察GFP表达.基因导入前后及处死前测定脑干诱发电位.结果实验组耳蜗铺片内外毛细胞缺失计数和对照组无统计学意义;荧光显微镜下见术侧半规管、前庭、耳蜗均有荧光表达,术后7d表达最强,以后减弱,术后28d还有表达;经半规管组前庭区表达强于耳蜗区,主要分布在前庭及外淋巴间隙;经圆窗组耳蜗区表达强于前庭区.对侧耳蜗及对照组动物呈阴性表达.手术前后脑干诱发电位差异无显著性.结论经半规管转导基因主要分布在前庭器官及外淋巴间隙,对耳蜗功能影响不大,是一种可行的途径;腺病毒载体携带的基因表达有一定的时间性.     

对缺血耳蜗鼓阶与前庭灌注的不同生理效应

用含氧人工外淋巴液灌注豚鼠耳蜗缺血之前庭阶及鼓阶，通过记录EP（内淋巴电位）及中阶PO。法，观察0。进入中阶之途径。腹倒入路打开听泡，T转播入微型玻璃管灌注人工外淋巴液，顶转造口引流。2转记录EP及中阶氧分压。结扎豚鼠升主动脉，造成耳蜗缺血动物模型，以不同速度灌注不同含氧量的人工外淋巴液。EP记录结果表明，高氧高速液体灌注前庭阶5分钟后EP完全恢复到缺血前的水平。而用相同液体高速灌注鼓阶5分钟后，EP则不能完全恢复，其数值约为灌注前庭阶后的一半。用高氧低速，低氧低速及低氧高速液体灌流鼓阶，EP没有明显改变。…     

卡那霉素联合速尿致聋豚鼠的Math1基因治疗

目的 观察卡那霉素和速尿联合致聋豚鼠耳蜗鼓阶导入Math1基因后的形态学及功能改变,探讨Mathl基因治疗药物中毒性耳聋的可行性.方法 健康成年豚鼠经硫酸卡那霉素(500 mg/kg)和速尿(50 mg/kg)联合致聋,将听性脑干反应(ABR)反应阈＞95 dB SPL的豚鼠按随机数字表法分为空白对照组(不做任何处置,3只),手术对照组(右耳单纯鼓阶钻孔,3只),人工外淋巴液组(右耳鼓阶钻孔导入人工外淋巴液,3只),单纯病毒载体组[右耳鼓阶钻孔导入携带增强型绿色荧光蛋白基因(enhanced green fluorescent protein,EGFP)的重组腺病毒(Ad.EGFP),4只]、Math1基因治疗组[右耳鼓阶钻孔导入携带Math1及EGFP基因的重组腺病毒(Ad.Math1-EGFP),6只].各组动物分别于鼓阶注射前及注射后8周时行ABR测试,结束测试后处死动物,取出耳蜗组织行扫描电镜观察.结果 各组豚鼠不同频率(4、8、16、20 kHz)短纯音ABR阈值在不同检测时间段差异均无统计学意义,组间比较差异亦无统计学意义(P值均＞0.05).除Math1基因治疗组外,其余各组右耳耳蜗各回毛细胞形态和数目与左耳(自身对照)比较无明显差别.4只Math1基因治疗组豚鼠中,有2只右耳耳蜗第三回内、外毛细胞数量明显比左耳多,其中内毛细胞排列形态较外毛细胞整齐.结论 鼓阶显微注射导入Math1基因能使部分卡那霉素和速尿联合致聋豚鼠的耳蜗毛细胞修复或再生,但其听觉功能没有改善.     

Math1基因导入成年大鼠前庭有效途径的探索

目的探索Math1基因导人大鼠前庭简便有效的方法和途径,为前庭功能障碍基因治疗的相关研究提供参考。方法将20只成年Wistar大鼠分为缺失E1、E3基因片段且构建有Math1基因和增强型绿色荧光蛋白报告基凶的复制缺陷型腺病毒（adnovirus—Math1—enhanced green fluorescence protein,Ad—Math1—EGFP）鼓阶导入组和前庭阶导人组．Ad—Math1—EGFP导入组大鼠在右耳通过耳蜗底转鼓阶或前庭阶打孔的方法导人物理滴度为2．1×1011v．p／ml的上述腺病毒5μl。在导入3天、7天后分别将动物处死,进行GFP表达观察。结果导入Ad—Mathl—EGFP3天后,前庭阶导入组大鼠的前庭终末器官及耳蜗均出现明显的GFP阳性表达;而鼓阶导入组的表达则局限于耳蜗,7天后仍未见前庭终末器官的GFP阳性表达。结论耳蜗底转前庭阶打孔可以作为Math1基因导入大鼠前庭简便有效的途径。     

经完整圆窗膜途径EGFP基因在大鼠耳蜗中的表达

目的 研究经完整圆窗膜途径进行耳蜗基因转导的可行性及安全性，为内耳基因治疗提供实验基础和理论依据。方法 24只SD大鼠术前及术后分别行听性脑干反应(ABR)检查。实验组(18只)用阳离子脂质体携带的增强型绿色荧光蛋白(enhanced green fluoresent protein，EGFP)基因，对照组(6只)用生理盐水，注入置于圆窗龛处的明胶海绵内。分别于术后3、7、14天取双侧耳蜗标本做基底膜铺片观察。结果 于圆窗龛处放置明胶海绵的转导方法对听力无明显影响。转染耳蜗呈明显的绿色荧光。3天组表达产物最高，7天组逐渐降低，14天组更弱。对侧及对照组耳蜗均未见荧光表达。结论 于圆窗龛处放置明胶海绵进行基因转导的方法对听力没有影响，且能够成功转染耳蜗组织，是一种行之有效的方法。     

经鼓阶胚胎干细胞内耳导入的初步观察

目的观察未经体外诱导的胚胎十细胞（embyonic stem cells,ESC）导入听力正常大鼠内耳的可行性以及导入后的存活和分布情况,为ESC内耳移植治疗由毛细胞缺失导致的感音神经性耳聋提供实验基础和理论依据。方法5—6周龄Wistar大鼠,10只,右耳为实验耳：经鼓阶打孔法植入带有绿色荧光蛋白（EGFP）的ESCs;左耳为对照组,不实施手术。术前1周与术后即刻行听性脑干反应（ABR）检查,取双侧耳蜗做冰冻切片,观察ESCs植入内耳后存活和分布情况。结果术后动物存活8只,麻醉效果好无干扰完整测完ABR动物5只。鼓阶打孔途径导入耳蜗的ESCs大部分于鼓阶聚集悬浮,少数可在鼓阶基底膜嵴和鼓阶外侧壁处贴壁;未在柯替器等中阶部位巾发现有ESCs的分布。ABR检测结果显示鼓阶打孔途径导入方法对大鼠听力影响较小。结论胚胎干细胞可经耳蜗底转鼓阶打孔途径导入耳蜗。干细胞在内耳成功存活,并且对内耳损伤小,因此。它可以作为内耳细胞移植的重要方式。     

Ventral approach to rat inner ear preserves cochlear function

CONCLUSION: This technique enabled us to visualize the cochlea without causing damage. OBJECTIVE: The mammalian inner ear is difficult to approach surgically. This is particularly true in the cases of the rat and mouse, which both have small cochleae. Rat and mouse research is particularly important because their genomes are well characterized, and significantly similar to that of the human. The aim of the present study was to develop a method of accessing the rat cochlea without affecting its function. MATERIALS AND METHODS: In the ventral approach, a small hole was made for access to the scala tympani. Cochlear function was assessed through auditory brainstem response (ABR) threshold measurements. RESULTS: The ventral approach enabled the direct visualization of the tympanic bulla. Thus, the tympanic bulla could be easily opened in a manner that was benign to cochlear function. There was no significant difference in ABR threshold before and after surgery.     

Sendai virus vector-mediated transgene expression in the cochlea in vivo

We injected a recombinant Sendai virus (SeV) vector into the guinea pig cochlea using two different approaches--the scala media and scala tympani--and investigated which cell types took up the vector. The hearing threshold shift and distribution of transfected cells in animals using the scala media approach were different compared to those using the scala tympani approach. SeV can transfect very different types of cells, including stria vascularis, spiral ganglion neurons, and sensory epithelia of the organ of Corti, and fibrocytes of the scala tympani. Because SeV vectors can potentially deliver stimuli to the cochlea to induce hair cell regeneration, it may be a powerful tool for repairing the organ of Corti.     

Surgical techniques for cell transplantation into the mouse cochlea

This study investigated surgical procedures for cell transplantation into the mouse inner ear. Female C57BL/6 mice were used as recipient animals. Fetal mouse neural stem cells expressing green fluorescence were used as donor cells. Two methods, an injection of transplants from the lateral semicircular canal (LSCC) and from the cochlear lateral wall (CLW), were examined. Two weeks after transplantation, the distribution of transplant-derived cells in the cochlea was examined. Effects on auditory function were assessed by measurement of auditory brain stem responses (ABRs). Cochleae receiving cell transplantation from the LSCC exhibited robust survival of transplant-derived cells mainly in the scala vestibuli and scala tympani. Transplantation from the LSCC caused elevation of ABR thresholds by less than 10 dB SPL. However, transplantation from the CLW resulted in considerable hearing loss, even though transplant-derived cells settled in the scala media. These findings demonstrate that an approach from the LSCC can be utilized for cell transplantation into the perilymph without causing apparent auditory disorder, while an approach from the CLW delivers cells to the endolymph but appears to cause auditory dysfunction.     

两种内淋巴给药方式对豚鼠耳蜗功能和形态的影响

目的 观察经耳蜗侧壁打孔(侧壁径路)和经圆窗膜、基底膜穿刺(双膜径路)两种内淋巴系统给药方式对豚鼠耳蜗整体形态结构和功能的影响并比较两种方式的优劣.方法 40只正常健康杂色豚鼠分为A、B两组(每组20只),所有动物左侧为给药耳,右侧为非给药耳.A组采用侧壁径路进入中阶灌注携带增强型绿色荧光蛋白基因的5型重组腺病毒(adenovirus5-enhanced green fluorescence protein,AdS-EGFP)5 μl;B组采用双膜径路进入中阶灌注AdS-EGFP 5μl.给药前后行听性脑干反应(ABR)测试,观察听功能改变.耳蜗冰冻切片直接荧光观察腺病毒分布,HE染色观察手术径路的愈合情况.基底膜铺片鬼笔环肽染色观察毛细胞受损情况,扫描电镜观察局部损害情况.结果 所有动物术后均存活.穿刺部位修复良好,耳蜗的完整性得以保持.EGFP在Corti器和血管纹内壁细胞内标记明显,表明两种给药径路都可以将药物成功注入内淋巴系统.A组证实成功14只(70%),手术前后ABR反应阈(声压级)变化[(33.1±10.3)dB]与对侧非给药耳[(9.4±3.9)dB]比较差异具有统计学意义(F=46.34,P=0.0005);B组证实成功8只(40%)手术前后阈值改变[(2.5±3.8)d8]与对侧耳[(2.5±3.8)dB]比较差异无统计学意义(F=0.00,P=1.000).两种方法在部分动物中都有药物渗漏入外淋巴的现象,给药局部产生炎性反应,侧壁径路对毛细胞的损害范围大于双膜径路.结论 两种手术径路都可将药物成功注人豚鼠耳蜗的内淋巴系统中,局部有炎性反应,术后耳蜗的完整性可以获得完全恢复.侧壁径路对豚鼠耳蜗毛细胞缺失和ABR反应阈的影响大于双膜径路,但是经侧壁径路进入中阶的手术成功率高于双膜径路,选择何种灌注径路需要根据实验要求来定.     

豚鼠耳蜗的转基因表达及其意义

目的:探讨耳蜗转基因表达的方法及意义。方法:经圆窗将复制缺陷重组腺病毒(含β-半乳糖苷酶基因,Ad.LacZ)注入豚鼠一侧耳蜗(接种耳)鼓阶,1周后观察接种耳及对侧耳蜗(非接种耳)转基因表达及听力情况。结果:接种耳蜗及对侧耳蜗均有Ad.LacZ表达,其分布相似,但对侧耳蜗中Ad.LacZ基因表达相对较弱,双侧耳接种Ad.LacZ前后听力无明显改变。结论:对侧耳蜗的转基因表达可能对某些内耳疾病的转基因治疗具有重要意义。     

Blockage of cochlear aqueduct for examination of perilymph (guinea pig) (author's transl)

To prevent the perilymph (guinea pig) from contamination with CSF during the sampling the aqueductus cochleae (AC) was blocked by injection of tissue adhesive into the meningeal aperture. The control of an exact blockage of AC was carriedout by examination of perilymph-outflow after opening the cochlea (injection of fluorescein-Na into the CSF-space), analysis of perilymph-protein-concentration, macroscopic and microscopic examination of the temporal bones. In all cochleae we have found the same morphological structures, notwithstanding whether the AC was blocked (for a time from 30 min to 7 weeks) or not: The cochlear aqueduct is filled with a mesh of mesenchymal tissue, which grows more dense towards the cochlear aperture andcontinues into the round window membrane. From scala tympani the AC is always limited by one layer of cells forming a sort of membrane (under light microscope). It seems possible that CSF moves in the inner of the round window membrane between AC and subepithelian space of middle ear mucosa, whereas perilymph of scala tympani is not in direct contact with the flow of CSF. The scala tympanic side of the round window membrane may be a big area for diffusion and there also may be an exchange between CSF and perilymph. The outflow of CSF into the cochlea after experimental opening of the cochlea is an artifact, caused by damage of pressure equilibration between CSF-space and cochlea. 30 min and 5--7 weeks after blockage no morphologicaland electrophysiological alterations from those of the control ears were to be seen. The protein concentration, however, increased significantly 5--7 weeks after blockage from normally about 200 mg/100 ml toalmost the double especially in the scala tympani (see Table 1).     

HOX-GFP and WOX-GFP lentivirus vectors for inner ear gene transfer

CONCLUSION: GFP transgene was expressed in the lining cells of the perilymphatic space. Lentivirus vectors are safe and cause only minimal inflammatory reaction. Transgene products can be delivered into the perilymph by utilizing lentivirus vectors. OBJECTIVES: To analyze the efficiency and safety of lentiviral vectors HOX-GFP and WOX-GFP in intracochlear gene transfer. MATERIALS AND METHODS: Lentivirus vectors were tested for their transduction efficiency in vivo in CD-1 mice. Half of the animals were pretreated with kanamycin. Lentivirus vector or saline (1 microl) was injected into the inner ear. All the animals were sacrificed 14 days after the surgery and the cochleae and selected organs were analyzed immunohistochemically. RESULTS: HOX-GFP and WOX-GFP expression was restricted to the lining cells of the scala tympani and scala vestibuli. No GFP expression was seen in the organ of Corti or the spiral ganglion. Aminoglycoside treatment had no effect on the expression of these vectors. The distant spread of lentivirus vectors was minimal; only the liver of one animal showed some GFP expression. Inflammatory reaction caused by these vectors was mild. Few inflammatory cells were found in the perilymphatic space of the cochlea and in the vestibular organ.