Division of Otolaryngology, Departments of Surgery, UCSD School of Medicine, San Diego, CA 92093, USA.
Neuroscience. 2010 Apr 14;166(4):1185-93. doi: 10.1016/j.neuroscience.2009.12.064. Epub 2010 Jan 6.
Adenovirus vectors (AdVs) are efficient tools for gene therapy in many tissues. Several studies have demonstrated successful transgene transduction with AdVs in the inner ear of rodents [Kawamoto K, Ishimoto SI, Minoda R, Brough DE, Raphael Y (2003) J Neurosci 23:4395-4400]. However, toxicity of AdVs [Morral N, O'Neal WK, Rice K, Leland MM, Piedra PA, Aguilar-Cordova E, Carey KD, Beaudet AL, Langston C (2002) Hum Gene Ther 13:143-154.] or lack of tropism to important cell types such as hair cells [Shou J, Zheng JL, Gao WQ (2003) Mol Cell Neurosci 23:169-179] appears to limit their experimental and potential clinical utility. Histone deacetylase inhibitors (HDIs) are known to enhance AdV-mediated transgene expression in various organs [Dion LD, Goldsmith KT, Tang DC, Engler JA, Yoshida M, Garver RI Jr (1997) Virology 231:201-209], but their effects in the inner ear have not been documented. We investigated the ability of one HDI, trichostatin A (TSA), to enhance AdV-mediated transgene expression in inner ear tissue. We cultured neonatal rat macular and cochlear explants, and transduced them with an AdV encoding green fluorescent protein (Ad-GFP) under the control of a constitutive promoter for 24 h. In the absence of TSA, GFP expression was limited, and very few hair cells were transduced. TSA did not enhance transduction when applied at the onset of Ad-GFP transduction. However, administration of TSA during or just after Ad-GFP application increased GFP expression in supporting cells approximately fourfold. Moreover, vestibular hair cell transduction was enhanced approximately sixfold, and that of inner hair cells by more than 17-fold. These results suggest that TSA increases AdV-mediated transgene expression in the inner ear, including the successful transduction of hair cells. HDIs, some of which are currently under clinical trials (Sandor et al., 2002), could be useful tools in overcoming current limitations of gene therapy in the inner ear using Ad-GFP.
腺病毒载体 (AdVs) 是在许多组织中进行基因治疗的有效工具。多项研究表明，腺病毒载体在啮齿动物内耳中能够成功转导转基因 [Kawamoto K、Ishimoto SI、Minoda R、Brough DE、Raphael Y（2003）J Neurosci 23:4395-4400]。然而，腺病毒载体的毒性 [Morral N、O'Neal WK、Rice K、Leland MM、Piedra PA、Aguilar-Cordova E、Carey KD、Beaudet AL、Langston C（2002）Hum Gene Ther 13:143-154] 或缺乏对毛细胞等重要细胞类型的嗜性 [Shou J、Zheng JL、Gao WQ（2003）Mol Cell Neurosci 23:169-179] 似乎限制了它们的实验和潜在临床应用。已知组蛋白去乙酰化酶抑制剂 (HDIs) 可以增强各种器官中腺病毒介导的转基因表达 [Dion LD、Goldsmith KT、Tang DC、Engler JA、Yoshida M、Garver RI Jr（1997）Virology 231:201-209]，但它们在内耳中的作用尚未得到证实。我们研究了一种 HDI，曲古抑菌素 A (TSA)，增强腺病毒介导的内耳组织中转基因表达的能力。我们培养新生大鼠黄斑和耳蜗外植体，并在无 TSA 的情况下用编码绿色荧光蛋白 (Ad-GFP) 的腺病毒转导它们 24 小时。在没有 TSA 的情况下，GFP 表达受限，很少有毛细胞被转导。TSA 并未在 Ad-GFP 转导开始时增强转导。然而，在 Ad-GFP 应用期间或之后给予 TSA 可使支持细胞中的 GFP 表达增加约四倍。此外，前庭毛细胞的转导增加了约六倍，内毛细胞的转导增加了 17 倍以上。这些结果表明，TSA 可增加腺病毒介导的内耳中转基因表达，包括毛细胞的成功转导。一些 HDIs 目前正在临床试验中（Sandor 等人，2002），可作为使用 Ad-GFP 克服内耳基因治疗当前局限性的有用工具。
