病毒载体的基因治疗的小鼠视网膜色素上皮缘方针，视网膜下注射
Summary
Subretinal injection is a surgical technique for effective gene delivery to retinal pigment epithelium in the mouse eye. Here we describe an easy and replicable method for subretinal injection of viral vectors to retinal pigment epithelium in experimental mice.
Abstract
The eye is a small and enclosed organ which makes it an ideal target for gene therapy. Recently various strategies have been applied to gene therapy in retinopathies using non-viral and viral gene delivery to the retina and retinal pigment epithelium (RPE). Subretinal injection is the best approach to deliver viral vectors directly to RPE cells. Before the clinical trial of a gene therapy, it is inevitable to validate the efficacy of the therapy in animal models of various retinopathies. Thus, subretinal injection in mice becomes a fundamental technique for an ocular gene therapy. In this protocol, we provide the easy and replicable technique for subretinal injection of viral vectors to experimental mice. This technique is modified from the intravitreal injection, which is widely used technique in ophthalmology clinics. The representative results of RPE/choroid/scleral complex flat-mount will help to understand the efficacy of this technique and adjust the volume and titer of viral vectors for the extent of gene transduction.
Introduction
在眼科，基因治疗已成为治疗方式在单基因遗传性视网膜病变。存在与基因在视网膜色素上皮细胞（RPE）包括莱伯先天性amurosis 1,2，色素性视网膜炎3，和脉络膜4相关遗传性视网膜病变。基因治疗的研究领域正在扩大在临床前研究和使用病毒载体的临床试验，例如腺机相关病毒（AAV）， 慢病毒 （LV）和腺病毒 （广告）5。不同的病毒载体具有不同的取向，在视网膜上。一种安全有效的基因治疗，病毒载体应仔细根据靶细胞和靶基因。
基因递送途径也很重要，为有效的基因递送至靶细胞，因此，应该仔细选择为好。用于眼内递送病毒载体的两种最常见的方法是subretINAL注射玻璃体内注射6。后者，玻璃体内注射，已被广泛地用于药物输送到治疗在湿性年龄相关性黄斑变性（AMD）和黄斑水肿脉络膜新生血管形成，糖尿病性视网膜病7。玻璃体内途径提供的病毒载体到玻璃体和视网膜内层的暴露，但向量到外视网膜的扩散受到限制。另一方面，在视网膜下途径提供直接递送病毒载体到视网膜和RPE之间的潜在空间，诱导局部疱。因此，视网膜下注射是目前被认为用于靶向感光细胞和RPE一个更有效的路由。在手术方式上，玻璃体被选为安全区的玻璃体内注射，避免在人类患者视网膜损伤。通过简单地修改这个方法给小鼠，我们可以通过角膜缘视网膜下的方法或intravireally注入病毒载体。
在这个视频本文中，我们证明视网膜下注射病毒载体的容易且方便的方法到小鼠视网膜色素上皮。在后方缘用30 G 1/2单针穿刺后，一个33克钝针配备微升注射器插入通过角膜缘穿刺部位的视网膜下腔。 1.5病毒载体 – 2微升体积被注入到视网膜和RPE诱导视网膜下泡之间的潜在空间。这个过程可以在直视下使用手术显微镜下进行。反复练习将保证复制的结果，即使没有气泡形成的直接可视化。这将有助于研究人员进行精确和节省时间用于实验的小鼠视网膜色素上皮基因传递。
Protocol
Representative Results
Discussion
在这个视频文章中，我们介绍了缘，方法视网膜下注射技术详细RPE /脉络膜/巩膜平座的代表性成果。这是一个简单而方便的技术为视网膜下注射病毒载体进入RPE。的气泡形成在注射过程中直接可视化是准确的交货期为初学者的一个重要步骤。有在Journal引入可视化实验8-10中某些视网膜下注射技术。视网膜下空间是视网膜和RPE之间的潜在空间，因此有两种可能的路由接近视网膜下的空间…
Divulgaciones
The authors have nothing to disclose.
Acknowledgements
这项研究是由首尔国立大学研究资助（800-20140542）的支持下，先锋研究计划NRF / MEST的（2012-0009544），和NRF / MEST的生物信号分析技术创新计划（2009-0090895），及NRF / MEST的格兰特（2015M3A9E6028949）。
Materials
| TWEEZERS DUMONT #5 11cm DUMOSTAR 0.1 x 0.06 mm TIPS | WPI | 500233 | |
| VANNAS Scissors S/S, 105mm | WPI | 555583S | |
| 33G Blunt needle | WPI | NF33BL-2 | |
| NanoFil Syringe, 10 microliter | WPI | NANOFIL | |
| RPE-KIT | WPI | RPE-KIT | For easy one hand injection |
| 30Gx1/2 (0.3mmx 13mm) BD PrecisionGlideTM Needle | BD | 305107 | Initial puncture for subretinal injection |
| Microscope Cover Glasses (No. 1 3 mm diameter) | Warner Instruments | 64-0720 (CS-3R) | |
| Leica operating microscope | Leica | LM M80 | |
| Fluoresecein microscope | Nikon | Eclipse 80i | |
| Lentivirus | Thermo scientific | TMO.LV-Ctr | Used to dilute vectors |
| PBS | Gibco | 10010-015 | Used to dilute vectors |
| Troperin (Phenylephrin 0.5%-Tropicamide 0.5%) | Hanmi | For dilation | |
| Proparacaine Hydrochloride Ophthalmic Solution USP, 0.5% (Sterile) | Bausch&Lomb | For topical anesthesia | |
| Healon GV OVD | Abbott Medical Optics Inc. | ||
| Zoletil 50 (tiletamine hypochloride and zolazepam hypochloride) | Virbac | For general anesthesia | |
| Rompun® injection (Xylazine HCl) | Bayer | For general anesthesia |
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