Nicole Vella (Macquarie University) for providing reagents; Alexia Saunder (Bionics Institute; BI), Michelle McPhedran (BI), Chris Williams (BI) for experimental support; the Royal Victorian Eye and Ear Hospital (RVEEH) Biological Research Centre staff for animal care; Sue Pierce (RVEEH) for veterinary advice; Anthony Burkitt (Bionic Vision Australia; BVA), Tamara Brawn (BVA) and the BVA staff for administrative support. 
This research was supported by the Australian Research Council (ARC) through its Special Research Initiative (SRI) in Bionic Vision Science and Technology grant to Bionic Vision Australia (BVA). The Bionics Institute receives Operational Infrastructure Support from the Victorian Government and also acknowledges support from the Bertalli Family Trust and the J T Reid Charitable Trust. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.
The Bionic Vision Australia Consortia authors for this manuscript are (a-z): 
Penelope J. Allen, Owen Burns, Kate E. Fox, Kumaravelu Ganesan, David J. Garret, Hamish Meffin, Joel Villalobos, and Jonathan Yeoh.

注：所有程序批准了皇家的维多利亚眼耳医院动物研究与伦理委员会（AEC RVEEH;＃10-199AB）。受试者根据国家卫生及（2013年）和“防止虐待动物法”医学研究理事会的“实践的护理和使用动物用于科学目的澳洲代码”处理（1986;和修正）。所有手术，临床评估和电程序进行麻醉下，并尽一切努力，以减少痛苦。 1.眼球摘除术和内固定注：按照详细的同伴手稿16所描述的眼球摘除和固定的程序，以围绕设备的电缆或玻璃体切割口格外小心，如果存在的话。简单地说，这涉及到： <ol><li> Transcardially灌注用温生理盐水后冷中性buffe主题红色的福尔马林。 </li><li>配合缝合眼球，作为地标。 </li><li>剜除眼球16，保持设备电缆及附件补丁/标签。 </li><li>后期修复眼18戴维森的解决方案 - 36小时。 </li><li>转移到50％乙醇为6 - 8小时。 </li><li>转移到70％乙醇和冷藏（4℃），直到解剖。 </li></ol> 2.电极拆卸和解剖。 注意：不是所有视网膜植入物将具有相同的外形尺寸，但一般会有一个电极阵列和某些形式的柔性和适形的载体材料。被临时固定到视网膜器件具有其中金属钉穿透阵列和眼球后部，保持这些共同一个钉孔。 <ol><li> Visualise植入物与在那里被固定到视网膜上的点。 <ol><li>用15度的刀片进行圆周跨角膜切口，取出角膜瓣为expOSE底层光圈和镜头。 </li><li>使用15度的刀片，disinsert透镜的悬韧带的纤维和全盘取下镜片，露出后房与视网膜植入物和金属钉原位 。 </li></ol></li><li>根据正在执行的种植和研究，在进一步解剖删除多余的组件。 注意：在本实施例中，视网膜前阵被评估由容纳在保形硅载体中的原型密封金刚石电极和电子封装（在内部产生的;参见20）。 <ol><li>在这里，仔细解剖精用手术刀提取金刚石电极包。离开植入物的有机硅主体随着视网膜粘性和铂布线的残余（ 图2）。如果嵌入式阵列/外壳不被调查的设备设计的一部分，则省略该步骤（2.2）。 </li></ol></li><li>小心解剖一个样品，它包括在所期望的方向的粘性和周围的组织。用细清扫剪刀剪下全部厚度条从眼球后部，包括巩膜，脉络膜和视网膜。取一个样品，这给钉的纵向横截面，示出所有相邻的粘性的视网膜层（ 图2） 注：供试品的所需取向可以有所不同，取决于所希望的具体结果。例如，如果一个人希望检查的粘性损坏视盘然后视盘应包含在样品内的接近。 </li></ol> 3.脱水，嵌入，安装，打磨，染色和成像<ol><li>脱水样品在渐进中乙醇阶段三天<ol><li>脱水在70％乙醇的样品2小时两次。 </li><li>脱水在80％的乙醇的样品2小时两次，然后O / N。 </li><li>脱水在90％的乙醇的样品2小时TWIC即</li><li>脱水在100％乙醇的样品2小时两次，然后O / N。 </li></ol></li><li>脱水在100％丙酮2小时的样品的两倍。 <ol><li>从丙酮中取出样品，并观察其光镜，因为它晾晒在室温下。样品转移到环氧树脂（参考步骤3.4）在开始之前卷曲/折叠。 注：从软组织造成倒塌细胞收缩去除液体。当组织卷曲/折叠发生的升值开发的经验。 </li></ol></li><li>根据制造商的指示准备的医疗级环氧树脂。以固化树脂，使用55℃，1小时或24小时，在RT。放置在真空室中进行约5分钟〜50毫巴以除去气泡。手动调节真空作为一个过度的真空会导致环氧混合煮沸，将不能有效地发生脱气 注：同时用3.2步执行步骤3.3。 </li><li>嵌入SAMP乐清晰的环氧树脂。浸入眼组织中脱气的环氧树脂在适当密封的容器中，并离开O / N在室温固化。 </li><li>照顾通过调整大小和重新嵌入固化的环氧块嵌入到所需的取向（ 图2）的样品。再嵌入含眼组织，使得粘性的长轴被定向为平行于所述模具的底部的调整块（黄色杯- 图3A）。 </li><li>安装树脂研磨试样座和研磨样品-使用碳化硅纸（230 250转与水有关，手工研磨）（从800网格; 图3C和3E）。 </li><li>对于染色，浸在甲苯胺蓝染色地面3 - 5分钟，或直到污渍发展（ 图3F）。 </li><li>用自来水冲洗（ 图3G）。 </li><li>图像具有高功率清扫范围检体的接地表面以可视化的蜂窝层视网膜（ 图3H）。适用于上述检体中的环氧树脂的顶部表面上的一滴蒸馏水以平滑衍射在空气 - 环氧接口。使用的光纤“鹅颈”光源照亮样本。 </li><li>重复步骤3.6 - 3.9，每次研磨掉样品的预先设定的厚度（试样保持器的最小精确和可重复的磨削幅度为20微米）。 </li></ol>

<ol>
	<li>Shepherd, R. K., Shivdasani, M. N., Nayagam, D. A., Williams, C. E., Blamey, P. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Visual+prostheses+for+the+blind.">Visual prostheses for the blind.</a> Trends Biotechnol. 31, 562-571 (2013).</li><li>Santos, A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Preservation+of+the+inner+retina+in+retinitis+pigmentosa.">Preservation of the inner retina in retinitis pigmentosa.</a> Arch Ophthalmol. 115, 511-515 (1997).</li><li>Humayun, M. S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Visual+perception+in+a+blind+subject+with+a+chronic+microelectronic+retinal+prosthesis.">Visual perception in a blind subject with a chronic microelectronic retinal prosthesis.</a> Vision Res. 43, 2573-2581 (2003).</li><li>Roessler, G., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Angiographic+findings+folowing+tack+fixation+of+a+wireless+epiretinal+retina+implant+device+in+blind+RP+patients.">Angiographic findings folowing tack fixation of a wireless epiretinal retina implant device in blind RP patients.</a> Graefes Arch Clin Exp Ophthalmol. 249, 1281-1286 (2011).</li><li>Chow, A. Y., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+artificial+silicon+retina+microchip+for+the+treatment+of+vision+loss+from+retinitis+pigmentosa.">The artificial silicon retina microchip for the treatment of vision loss from retinitis pigmentosa.</a> Arch Ophthalmol. 122, 460-469 (2004).</li><li>Zrenner, E., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Subretinal+electronic+chips+allow+blind+patients+to+read+letters+and+combine+them+to+words.">Subretinal electronic chips allow blind patients to read letters and combine them to words.</a> Proc Biol Sci. 278, 1489-1497 (2011).</li><li>Fujikado, T., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Testing+of+semichronically+implanted+retinal+prosthesis+by+suprachoroidal-transretinal+stimulation+in+patients+with+retinitis+pigmentosa.">Testing of semichronically implanted retinal prosthesis by suprachoroidal-transretinal stimulation in patients with retinitis pigmentosa.</a> Invest Ophthalmol Vis Sci. 52, 4726-4733 (2011).</li><li>Saunders, A. L., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Development+of+a+surgical+procedure+for+implantation+of+a+prototype+suprachoroidal+retinal+prosthesis.">Development of a surgical procedure for implantation of a prototype suprachoroidal retinal prosthesis.</a> Clin Experiment Ophthalmol. , (2013).</li><li>Lee, S. W., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Development+of+microelectrode+arrays+for+artificial+retinal+implants+using+liquid+crystal+polymers.">Development of microelectrode arrays for artificial retinal implants using liquid crystal polymers.</a> Invest Ophthalmol Vis Sci. 50, 5859-5866 (2009).</li><li>Sakaguchi, H., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Transretinal+electrical+stimulation+with+a+suprachoroidal+multichannel+electrode+in+rabbit+eyes.">Transretinal electrical stimulation with a suprachoroidal multichannel electrode in rabbit eyes.</a> Jpn J Ophthalmol. 48, 256-261 (2004).</li><li>Majji, A. B., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Long-term+histological+and+electrophysiological+results+of+an+inactive+epiretinal+electrode+array+implantation+in+dogs.">Long-term histological and electrophysiological results of an inactive epiretinal electrode array implantation in dogs.</a> Invest Ophthalmol Vis Sci. 40, 2073-2081 (1999).</li><li>Walter, P., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Successful+long-term+implantation+of+electrically+inactive+epiretinal+microelectrode+arrays+in+rabbits.">Successful long-term implantation of electrically inactive epiretinal microelectrode arrays in rabbits.</a> Retina. 19, 546-552 (1999).</li><li>Ray, A., Chan, L., Thomas, B., Weiland, J. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effects+of+prolonged+stimulation+at+the+electrode-retina+interface.">Effects of prolonged stimulation at the electrode-retina interface.</a> Conf Proc IEEE Eng Med Biol Soc. 1, 1285-1287 (2006).</li><li>Colodetti, L., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Pathology+of+damaging+electrical+stimulation+in+the+retina.">Pathology of damaging electrical stimulation in the retina.</a> Experimental eye research. 85, 23-33 (2007).</li><li>Nayagam, D. A. X., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Chronic+Electrical+Stimulation+with+a+Suprachoroidal+Retinal+Prosthesis:+A+Preclinical+Safety+and+Efficacy+Study.">Chronic Electrical Stimulation with a Suprachoroidal Retinal Prosthesis: A Preclinical Safety and Efficacy Study.</a> PLoS One. 9, e97182 (2014).</li><li>Nayagam, D. A. X., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Techniques+for+Processing+Eyes+Implanted+With+a+Retinal+Prosthesis+for+Localized+Histopathological+Analysis.">Techniques for Processing Eyes Implanted With a Retinal Prosthesis for Localized Histopathological Analysis.</a> Journal of visualized experiments : JoVE. , e50411 (2013).</li><li>Laube, T., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Development+of+surgical+techniques+for+implantation+of+a+wireless+intraocular+epiretinal+retina+implant+in+Gottingen+minipigs.">Development of surgical techniques for implantation of a wireless intraocular epiretinal retina implant in Gottingen minipigs.</a> Graefe's Archive For Clinical And Experimental Ophthalmology = Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie. 250, 51-59 (2012).</li><li>Gerding, H., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Successful+long-term+evaluation+of+intraocular+titanium+tacks+for+the+mechanical+stabilization+of+posterior+segment+ocular+implants.">Successful long-term evaluation of intraocular titanium tacks for the mechanical stabilization of posterior segment ocular implants.</a> Mat.-wiss. u. Werkstofftech. 32, 903-912 (2001).</li><li>Seo, J. -. M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Silicon+retinal+tack+for+the+epiretinal+&#64257;xation+of+the+polyimide+electrode+array.">Silicon retinal tack for the epiretinal &#64257;xation of the polyimide electrode array.</a> Current Applied Physics. 6, 649-653 (2006).</li><li>Hadjinicolaou, A. E., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Electrical+stimulation+of+retinal+ganglion+cells+with+diamond+and+the+development+of+an+all+diamond+retinal+prosthesis.">Electrical stimulation of retinal ganglion cells with diamond and the development of an all diamond retinal prosthesis.</a> Biomaterials. 33, 5812-5820 (2012).</li><li>Briggs, R. J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Comparison+of+round+window+and+cochleostomy+approaches+with+a+prototype+hearing+preservation+electrode.">Comparison of round window and cochleostomy approaches with a prototype hearing preservation electrode.</a> Audiol Neurootol. 11, 42-48 (2006).</li><li>Shepherd, R., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=An+improved+cochlear+implant+electrode+array+for+use+in+experimental+studies.">An improved cochlear implant electrode array for use in experimental studies.</a> Hear Res. 277, 20-27 (2011).</li><li>Tykocinski, M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Comparison+of+electrode+position+in+the+human+cochlea+using+various+perimodiolar+electrode+arrays.">Comparison of electrode position in the human cochlea using various perimodiolar electrode arrays.</a> Am J Otol. 21, 205-211 (2000).</li><li>Hardie, N. A., MacDonald, G., Rubel, E. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+new+method+for+imaging+and+3D+reconstruction+of+mammalian+cochlea+by+fluorescent+confocal+microscopy.">A new method for imaging and 3D reconstruction of mammalian cochlea by fluorescent confocal microscopy.</a> Brain Res. 1000, 200-210 (2004).</li></ol>

Authors have nothing to disclose. Irfan Durmo is an employee of Cochlear Ltd.

标准组织学技术目前无法处理原位硬金属植入物由于在切割这些对象与金属，玻璃或甚至金刚石刀片的限制。在我们的配套文件16，我们发现，使用修改的全眼球固定技术可以减少人为的视网膜分层。在目前的手稿，一个既定的研磨和抛光技术可视化人工耳蜗植入原位 21-23修改视网膜假体。的钛粘性，用来固定电极阵列到视网膜，epiretinally，包埋在环氧树脂沿与周围的眼组织。这种树脂块，然后导向适当且逐步地/抛光以揭示所述组织形态学紧邻金属粘性。该块在不同深度的抛光表面的图像用一个功能强大的解剖显微镜。这种技术是有用的：可视化和evaluat荷兰国际集团邻近视网膜植入物的组织反应;评估与植入物的植入相关的外科手术创伤;以确定生物反应到硬金属部件;并测量植入物和视网膜的表面之间的距离。 这种技术将在未来的安全性研究可用于在邻近于在眼睛视网膜的粘性或其他硬（ 如，金属）物体区域的原位可视化。这在评估假肢上涨到视网膜epiretinally的临床前安全性直接应用。它也可以是用于评估组织损伤的视网膜的区域与位于子视网膜位置的植入物接触是有用的。 有几种方法，以验证该技术已被正确地执行。在每个阶段，视网膜应保持附着在眼球的外层。如果没有人为的视网膜脱离总值（GDP），这可能会印度语吃与固定的问题。当样品被嵌入和重新定向在最终树脂阻断视网膜应接近正交与磨削面块;这将最大限度地减少斜向切割。检查增量研磨步骤来遍历一个对象（如视网膜粘性）所需（已知步长）的数目与对象的尺寸相应地关联是有用的。 该技术可以被优化以几种方式。与研磨过程相关联的环氧块的表面上的划痕可减小逐渐变细级抛光。对于本研究中，我们使用的800，1000，1200，2400和4000级碳化硅纸。钻石膏也可以用来改善表面光洁度。更精细的表面光洁度给出更高质量的图像，但在附加的抛光时间的成本。另一个重要的考虑因素对于提高该技术的结果是OPTI的选择和质量CS和照明用于图像捕获。其他基本的组织学染色 - 特别是尼氏染色，可代替甲苯胺蓝的可以使用，但可能需要进一步优化。一些污渍会弄脏树脂以及该组织（ 例如 ，曙红），因此一个浅抛光，可能需要在染色后除去背景变色。专门的污渍，荧光染料和免疫组化染色没有尝试，但除非一个非常特定的结果是期望的，在每个磨削级别执行这些污渍所需的时间可能是令人望而却步。然而，有可能的嵌入步骤（步骤3.4）24之前以染色组织作为一个整体。 该技术的主要限制是，一旦所感兴趣的区域已被磨掉，它不能被检索，因此，为谨慎起见，在各种放大倍数在研磨和抛光的每个阶段，捕捉许多（可能冗余）的图像。这是还重要的是使用较小的增量为每个磨削深度调整。这种技术的另一个限制是该光学放大倍率和分辨率的组织固定在玻璃载片上，并与一个标准（传输）光学显微镜观察比较的那个。进行原型设计和评估一个新颖的植入装置的安全性的目的，病理评估总值为主要兴趣。该技术提供了用于观察与视网膜粘性相关的临床相关损害的有效方法。通过实践，收集研磨，抛光和拍摄一个给定的样本（一旦嵌入）所需的总时间是不相上下的时候，将采取部分中的蜡块或冰冻切片。 还有要延伸到视网膜植入物的范围之外的应用对本技术的潜力。这种技术适合于评估所述组织邻近硬植入物，其中植入物的提取不feasibLE或会损坏接口。例如，该技术可以扩展到评价从金属（ 例如 ，铂，镍钛诺等 ），不能用常规的组织学技术切割，制成的植入物，如某些脑深部或外周神经的电极，插管用于药物递送，血管支架或矫形假肢。

色素性视网膜炎（RP）是一种遗传性疾病，导致感光体，它们是细胞中负责转导光视网膜的最外层的普遍丧失，在光子的形式，成神经活性。重要的是，患者的RP通常具有剩余的神经元在其视网膜的其它层，它们仍然起作用。视网膜假体能够通过针对这些存活的神经元电刺激来激活他们的视觉通路1,2恢复一些有限的视野，这些患者中。从临床试验的感性效果已经显示出可喜的早期结果和最近一些设备已被批准用于商业用途。目前，存在其中临床视网膜假肢已被定位的三个主要解剖学位置：epiretinally 3,4，视网膜下5,6和suprachoroidally 7,8。不同的设备利用不同的材料和它们的形式被定制到它们被植入的位置。然而，它们都构成视觉知觉通过激活视网膜的剩余神经元的电脉冲。 存在用于任何医疗假体损伤周围组织因初始放置的机械作用或随后持续力的潜力。在可植入刺激器，如视网膜假肢的情况下，存在的电气参数应该是在安全范围内的额外的考虑因素。病人的安全是最重要的，所以设备必须在临床前研究推进到临床设置9-15前的严格测试。在我们的同伴文章中，我们描述了用于评估周围定位在脉络膜上腔16的植入物的眼睛的局部组织病理学的方法。在本手稿中，我们描述用于可视眼组织周围的电极阵列上涨到视网膜epiretinally，在临床前的技术（FE线）模型（ 图1）。 在视网膜前的位置是定位视觉假体是最常用的位置。这里位于电极阵列通常固定到与该穿透眼睛17-20的所有层的金属粘着性视网膜。之前在本手稿中描述的技术，这是难以准确评估视网膜和直接围绕一个粘性其他组织。用中性缓冲的福尔马林标准眼球固定造成人为的视网膜损伤，由于视网膜和巩膜对粘性的固定点的差速运动。因此所造成的粘性和视网膜前阵的任何实际损害不能精确观察。另外，切片的眼组织不能与原位视网膜粘性进行作为金属物体不能容易地切断与传统组织学装置;去除粘性前组织处理也并不可取，因为这也导致人为的视网膜损伤。 本研究的目的是双重的：1），以减少视网膜脱离伪影，使得所引起的粘性和视网膜植入阵列的任何损坏能够可靠地评估;和2）以可视化相邻的粘性视网膜结构而不删除。为了达到目的，图1中，新的固定技术被利用，从而降低了人为的视网膜剥离（如在同伴文章16描述）。为了达到目的，2，我们修改的嵌入，研磨，和抛光技术中，最初在原位观察耳蜗植入电极21-23的开发。在这个手稿中描述的方法允许周围视网膜的可视化和邻近粘着在原位 ，同时尽量减少人为的视网膜损伤，因此允许所造成的粘性和视网膜前阵的任何潜在损害精确的评估。

<table border="0" cellpadding="0" cellspacing="0" width="853">
	<tbody>
		<tr height="42">
			<td height="42" style="height:42px;width:337px;">Name of the reagent / equipment</td>
			<td style="width:191px;">Company</td>
			<td style="width:176px;">Catalogue number</td>
			<td style="width:151px;">Comments (optional)</td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:337px;">Acetone</td>
			<td style="width:191px;">Chem-Supply</td>
			<td style="width:176px;">AA008</td>
			<td style="width:151px;">Propanone BHD Medical grade</td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:337px;">Epo-Tek 301 Epoxy</td>
			<td style="width:191px;">Epoxy Technology</td>
			<td style="width:176px;">Part A 1675-54-3 Part B 9046-10-0</td>
			<td style="width:151px;"></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:337px;">Ethanol 70-75% v/v</td>
			<td style="width:191px;">Merck PTY LTD</td>
			<td style="width:176px;">4.10261</td>
			<td style="width:151px;">Alcohol</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:337px;">Ethanol</td>
			<td style="width:191px;">Merck PTY LTD</td>
			<td style="width:176px;">90143</td>
			<td style="width:151px;">Alcohol</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:337px;">Toluidine blue O</td>
			<td style="width:191px;">Sigma-Aldrich</td>
			<td style="width:176px;">T3260</td>
			<td style="width:151px;"></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:337px;">Ethylenediamine Tetraacetic Acid</td>
			<td style="width:191px;">Sigma-Aldrich</td>
			<td style="width:176px;"></td>
			<td style="width:151px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:337px;">TegraPol grinding/polishing machine</td>
			<td>Struers</td>
			<td>TegraPol-25</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:337px;">AccuStop specimen holder</td>
			<td style="width:191px;">Struers</td>
			<td style="width:176px;">Accustop</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Light microscope</td>
			<td>Leica</td>
			<td>MZ16</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Objective lens</td>
			<td>Leica</td>
			<td>2.0x Planapo Objective</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Digital Microscope Camera</td>
			<td>Leica</td>
			<td>DFC-420C</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Microscope Software</td>
			<td>Leica&#160;</td>
			<td>Application Suite v4.1.0</td>
			<td></td>
		</tr>
	</tbody>
</table>

techniques for processing eyes implanted with a retinal prosthesis for localized histopathological analysis: part 2 epiretinal implants with retinal tacks

Retinal prostheses for the treatment of certain forms of blindness are gaining traction in clinical trials around the world with commercial devices currently entering the market. In order to evaluate the safety of these devices, in preclinical studies, reliable techniques are needed. However, the hard metal components utilised in some retinal implants are not compatible with traditional histological processes, particularly in consideration for the delicate nature of the surrounding tissue. Here we describe techniques for assessing the health of the eye directly adjacent to a retinal implant secured epiretinally with a metal tack.
Retinal prostheses feature electrode arrays in contact with eye tissue. The most commonly used location for implantation is the epiretinal location (posterior chamber of the eye), where the implant is secured to the retina with a metal tack that penetrates all the layers of the eye. Previous methods have not been able to assess the proximal ocular tissue with the tack in situ, due to the inability of traditional histological techniques to cut metal objects. Consequently, it has been difficult to assess localized damage, if present, caused by tack insertion.
Therefore, we developed a technique for visualizing the tissue around a retinal tack and implant. We have modified an established technique, used for processing and visualizing hard bony tissue around a cochlear implant, for the soft delicate tissues of the eye. We orientated and embedded the fixed eye tissue, including the implant and retinal tack, in epoxy resin, to stabilise and protect the structure of the sample. Embedded samples were then ground, polished, stained, and imaged under various magnifications at incremental depths through the sample. This technique allowed the reliable assessment of eye tissue integrity and cytoarchitecture adjacent to the metal tack.

定影协议大幅减少人为的脱离和视网膜16的分层。环氧块内的试样的方向是使用中所述的两步嵌入处理取得一致。增量研磨过程所需手巧的中等水平，以达到最佳的效果，但得益于其提供的精确控制增量分辨率可调样品架。在所有情况下（N = 5）的粘性位于和地面/抛光与可取的和一致的结果。毗邻鞋钉的视网膜是解析并适当染色。抛光用等级P＃800的碳化硅纸环氧树脂块的表面就足以图像嵌入组织的细胞的宏观结构。更高等级的纸张，或金刚石浆料可以用来进一步抛光表面在任何给定深度如果需要的话。解剖显微镜和光学纤维“鹅颈”二极管灯吨源被认为是合适的成像地面块和嵌入的组织样本的表面上。光源的位置是变化的通过试验和错误来找到位置和角度，给了通过显微镜的最佳照明和对比度。加入一滴蒸馏水到块的表面上，在样品上方，是有用的，以减少在环氧空中接口的光路的衍射和/或光滑的失真。 图4示出了可视化紧邻钛视网膜的视网膜组织的例子的图像钉使用这种技术。非人为的视网膜脱离和折页上可以看到硅氧烷（ 图4A）的任一侧。粘性轴是可见的嵌入硅;粘性的头已经渗透视网膜和巩膜。有在未染色视网膜硅氧烷（ 图4C）的任一侧的非人为的视网膜脱离。该技术已经表明，在这种情况下，疗法e是相邻的视网膜中的一侧上的粘着性和压缩性视网膜解体由于斜插入角度。注意，呈现的图像仅仅是的技术中，不能代表不粘损伤组织病理学在一般的成功的插图。 <img alt="图1" src="/files/ftp_upload/52348/52348fig1highres.jpg" /> 图1.放置在视网膜的电极阵列。（A）眼显示后极部巩膜，脉络膜和视网膜退化（缺乏光感受器）的放大截面示意图。电极阵列中描绘了蓝色，贴epiretinally。一个视网膜前电极阵列（B）的计算机辅助绘图。一，集成电路（“芯片”）和电极包; B，钛视网膜粘性; C，医用级硅胶住房; D，铅出口点。 A组从原来的illustrati修改所提供的礼貌仿生视觉澳大利亚，版权贝丝十字。 <a href="https://www.jove.com/files/ftp_upload/52348/52348fig1large.jpg" target="_blank">请点击此处查看该图的放大版本。</a> <img alt="图2" src="/files/ftp_upload/52348/52348fig2highres.jpg" /> 图2.去除电极和眼睛的解剖。一个去核的猫科动物的眼睛原位视网膜粘性高动态范围照片，微距（A）固定后与戴维森的固定液维持视网膜结构16中，去核的眼睛解剖。电极阵列包被从硅酮载体去除（虚线正方形轮廓指示电极阵列的原始位置）与剩余的植入物的粘着性（箭头）和有机硅主体。（B）的眼解剖与相邻的纵截面钉（虚线）。的粘着性保持嵌入在眼罩（箭头）的后壁，通过巩膜主要稳定。物为树脂嵌入和研磨（右段）制备含有粘性的组织切片，而制备用于标准组织学处理16（左段）含有被删除的电极阵列下方的视网膜上的一节。 0.5 mm的增量标尺显示在每个面板的底部边缘。 <a href="https://www.jove.com/files/ftp_upload/52348/52348fig2large.jpg" target="_blank">请点击此处查看该图的放大版本。</a> <img alt="图3" src="/files/ftp_upload/52348/52348fig3highres.jpg" /> 图3.环氧树脂灌封和研磨的粘性和视网膜组织。嵌入式环氧树脂的照片，并对准组织样本，研磨，染色和粘性和视网膜组织的成像。（A）的交<html> K个样本包埋在环氧树脂块。使用的模具，将样品这样取向的纵向平面是平行于模具的底部。（B）中的环氧块中，安装在研磨试样保持器的固化后的环氧嵌段含有粘性样品（C）中 ，准备用于研磨（D）的样品定向的基本组织，使成像部分包含视网膜细胞层和粘着性的纵向轴线（E）的使用碳化硅纸在旋转磨床将样品地面（F）的接地表面块被甲苯胺蓝染色，以确定视网膜层。（G）中的块用自来水漂洗以除去过量的污点。（H），蓝染色视网膜层和粘着使用大功率清扫范围进行成像的甲苯胺。 广告/ 52348 / 52348fig4highres.jpg“/&gt; 图4.高和低功率的图像的粘着性和视网膜。在各点在研磨过程中图像用解剖范围，显示了粘性（星号）的纵向部分通过眼睛和巩膜（“S”穿透出射），相邻的硅（散列）和甲苯胺蓝染色和未染色的视网膜（“R”）。注意这些例子的图像仅用于说明本可视化技术，并不能代表全部视网膜植入物或粘着性插入组织学的结果。铂接线地面残存可见的面板AD（&#39;W&#39;）。（A）低功耗，大头钉穿透视网膜和巩膜的未染色的图像。（B）的视网膜脱离的高功率形象和折叠相邻未染色的视网膜到在粘性轴的中心的硅氧烷载体中图像A（C）的低放大率图像。 <str翁&gt;（D）的图像C.（E）的粘着性。在一个单独的样品的中心的高放大率图像，无硅酮载体的粘着性剑柄下方甲苯胺蓝染色的视网膜上的高功率图像显示，之前立即磨粘性轴（F）正常甲苯胺蓝染色的视网膜结构（GCL：视网膜神经节细胞层，INL：内核层，ONL：外核层; PR：感光; T：猫绒毡层灵芝）使用相同的研磨技术，可视化。比例尺在每块面板是：A和C = 2毫米; B和D = 500微米; E = 200微米; F = 100微米。

Watch this Scientific Journal Video about Techniques for Processing Eyes Implanted with a Retinal Prosthesis for Localized Histopathological Analysis: Part 2 Epiretinal Implants with Retinal Tacks at 

Techniques for Processing Eyes Implanted with a Retinal Prosthesis for Localized Histopathological Analysis: Part 2 Epiretinal Implants with Retinal Tacks

Here we describe histological techniques for visualising ocular tissue directly adjacent to a metal epiretinal tack and retinal prosthesis.

为处理眼植入视网膜假体的局部病理组织学分析技术：第2部分视网膜前植入视网膜大头钉

Retinal prostheses for the treatment of certain forms of blindness are gaining traction in clinical trials around the world with commercial devices ...

techniques-for-processing-eyes-implanted-with-retinal-prosthesis-for

Research

JoVE Journal

Medicine

11.4K 次观看.  Bionics Institute. Here we describe histological techniques for visualising ocular tissue directly adjacent to a metal epiretinal tack and retinal prosthesis. 

视频: Techniques for Processing Eyes Implanted with a Retinal Prosthesis for Localized Histopathological Analysis: Part 2 Epiretinal Implants with Retinal Tacks

Techniques for Processing Eyes Implanted With a Retinal Prosthesis for Localized Histopathological Analysis

With the recent development of retinal prostheses, it is important to develop reliable techniques for assessing the safety of these devices in preclinical studies. However, the standard fixation, preparation, and automated histology procedures are not ideal. Here we describe new procedures for evaluating the health of the retina directly adjacent to an implant. Retinal prostheses feature electrode arrays in contact with eye tissue. Previous methods have not been able to spatially localize the ocular tissue adjacent to individual electrodes within the array. In addition, standard histological processing often results in gross artifactual detachment of the retinal layers when assessing implanted eyes. Consequently, it has been difficult to assess localized damage, if present, caused by implantation and stimulation of an implanted electrode array. Therefore, we developed a method for identifying and localizing the ocular tissue adjacent to implanted electrodes using a (color-coded) dye marking scheme, and we modified an eye fixation technique to minimize artifactual retinal detachment. This method also rendered the sclera translucent, enabling localization of individual electrodes and specific parts of an implant. Finally, we used a matched control to increase the power of the histopathological assessments. In summary, this method enables reliable and efficient discrimination and assessment of the retinal cytoarchitecture in an implanted eye.

Techniques for visualizing retinal cytoarchitecture directly adjacent to individual electrodes within a retinal stimulator.

技术处理眼睛的视网膜假体植入局部组织病理学分析

With  the recent development of retinal prostheses, it is important to develop  reliable techniques for assessing the safety of these devices in ...

科研

医学

Quantitative Fundus Autofluorescence for the Evaluation of Retinal Diseases

The retinal pigment epithelium (RPE) is juxtaposed to the overlying sensory retina, and supports the function of the visual system. Among the tasks performed by the RPE are phagocytosis and processing of outer photoreceptor segments through lysosome-derived organelles. These degradation products, stored and referred to as lipofuscin granules, are composed partially of bisretinoids, which have broad fluorescence absorption and emission spectra that can be detected clinically as fundus autofluorescence with confocal scanning laser ophthalmoscopy (cSLO). Lipofuscin accumulation is associated with increasing age, but is also found in various patterns in both acquired and inherited degenerative diseases of the retina. Thus, studying its pattern of accumulation and correlating such patterns with changes in the overlying sensory retina are essential to understanding the pathophysiology and progression of retinal disease. Here, we describe a technique employed by our lab and others that uses cSLO in order to quantify the level of RPE lipofuscin in both healthy and diseased eyes.

The retinal pigment epithelium (RPE) supports the sensory retina through recycling visual cycle byproducts, which accumulate as lipofuscin. These products are autofluorescent and can be qualitatively imaged in vivo. Here, we describe a method to quantitatively image RPE lipofuscin using confocal scanning laser ophthalmoscopy.

定量自体荧光眼底视网膜疾病的评价

The retinal pigment epithelium (RPE) is juxtaposed to the overlying sensory retina, and supports the function of the visual system. Among the tasks ...

A Step by Step Protocol for Subretinal Surgery in Rabbits

Age related macular degeneration (AMD), retinitis pigmentosa, and other RPE related diseases are the most common causes for irreversible loss of vision in adults in industrially developed countries. RPE transplantation appears to be a promising therapy, as it may replace dysfunctional RPE, restore its function, and thereby vision.
Here we describe a method for transplanting a cultured RPE monolayer on a scaffold into the subretinal space (SRS) of rabbits. After vitrectomy xenotransplants were delivered into the SRS using a custom made shooter consisting of a 20-gauge metallic nozzle with a polytetrafluoroethylene (PTFE) coated plunger. The current technique evolved in over 150 rabbit surgeries over 6 years. Post-operative follow-up can be obtained using non-invasive and repetitive in vivo imaging such as spectral domain optical coherence tomography (SD-OCT) followed by perfusion-fixed histology.
The method has well-defined steps for easy learning and high success rate. Rabbits are considered a large eye animal model useful in preclinical studies for clinical translation. In this context rabbits are a cost-efficient and perhaps convenient alternative to other large eye animal models.

Retinal pigment epithelium (RPE) replacement strategies and gene-based therapy are considered for several retinal degenerative conditions. For clinical translation, large eye animal models are required to study surgical techniques applicable in patients. Here we present a rabbit model for subretinal surgery geared towards RPE transplantation, which is versatile and cost-efficient.

一种用于兔视网膜下手术分步协议

Age related macular degeneration (AMD), retinitis pigmentosa, and other RPE related diseases are the most common causes for irreversible loss of vision in ...

An Acute Retinal Model for Evaluating Blood Retinal Barrier Breach and Potential Drugs for Treatment

A low-cost, easy-to-use and powerful model system is established to evaluate potential treatments that could ameliorate blood retinal barrier breach. An inflammatory factor, histamine, is demonstrated to compromise vessel integrity in the cultured retina through positive staining of IgG outside of the blood vessels. The effects of histamine itself and those of candidate drugs for potential treatments, such as lipoxin A4, are assessed using three parameters: blood vessel leakage via IgG immunostaining, activation of M&#252;ller cells via GFAP staining and change in neuronal dendrites through staining for MAP2. Furthermore, the layered organization of the retina allows a detailed analysis of the processes of M&#252;ller and ganglion cells, such as changes in width and continuity. While the data presented is with swine retinal culture, the system is applicable to multiple species. Thus, the model provides a reliable tool to investigate the early effects of compromised retinal vessel integrity on different cell types and also to evaluate potential drug candidates for treatment.

A low-cost, easy-to-use and powerful system is established to evaluate potential treatments that could ameliorate blood retinal barrier breach induced by histamine. Blood vessel leakage, M&#252;ller cell activation and the continuity of neuronal processes are utilized to assess the damage response and its reversal with a potential drug, lipoxin A4.

急性视网膜模型评估血视网膜屏障违约和潜在的药物治疗

A low-cost, easy-to-use and powerful model system is established to evaluate potential treatments that could ameliorate blood retinal barrier breach. An ...

Studying Diabetes Through the Eyes of a Fish: Microdissection, Visualization, and Analysis of the Adult tg(fli:EGFP) Zebrafish Retinal Vasculature

Diabetic retinopathy is the leading cause of blindness among middle-aged adults. The rising prevalence of diabetes worldwide will make the prevention of diabetic microvascular complications one of the key research fields of the next decades. Specialized, targeted therapy and novel therapeutic drugs are needed to manage the increasing number of patients at risk of vision-loss. The zebrafish is an established animal model for developmental research questions with increasing relevance for modeling metabolic multifactorial disease processes. The advantages of the species allow for optimal visualization and high throughput drug screening approaches, combined with the strong ability to knock out genes of interest. Here, we describe a protocol which will allow easy analysis of the adult tg(fli:EGFP) zebrafish retinal vasculature as a fast read-out in settings of long-term vascular pathologies linked to neoangiogenesis or vessel damage. This is achieved via dissection of the zebrafish retina and whole-mounting of the tissue. Visualization of the exposed vessels is then achieved via confocal microscopy of the green EGFP reporter expressed in the adult retinal vasculature. Correct handling of the tissue will lead to better outcomes and less internal vessel breakage to assure the visualization of the unaltered vascular structure. The method can be utilized in zebrafish models of retinal vasculopathy linked to changes in the vessel architecture as well as neoangiogenesis.

Studying Diabetes Through the Eyes of a Fish: Microdissection, Visualization, and Analysis of the Adult tgfli:EGFP Zebrafish Retinal Vasculature

Here, we discuss a method protocol which will allow an easy analysis of the adult tg(fli:EGFP) zebrafish retinal vasculature as a fast read-out in settings of long-term vascular pathologies linked to neoangiogenesis and structural changes.

通过鱼眼研究糖尿病: 成人 tg (fli: EGFP) 斑马鱼视网膜血管的显微解剖、可视化和分析

Diabetic retinopathy is the leading cause of blindness among middle-aged adults. The rising prevalence of diabetes worldwide will make the prevention of ...

Biotribological Testing and Analysis of Articular Cartilage Sliding against Metal for Implants

Osteochondral defects in middle-aged patients might be treated with focal metallic implants. First developed for defects in the knee joint, implants are now available for the shoulder, hip, ankle and the first metatarsalphalangeal joint. While providing pain reduction and clinical improvement, progressive degenerative changes of the opposing cartilage are observed in many patients. The mechanisms leading to this damage are not fully understood. This protocol describes a tribological experiment to simulate a metal-on-cartilage pairing and comprehensive analysis of the articular cartilage. Metal implant material is tested against bovine osteochondral cylinders as a model for human articular cartilage. By applying different loads and sliding speeds, physiological loading conditions can be imitated. To provide a comprehensive analysis of the effects on the articular cartilage, histology, metabolic activity and gene expression analysis are described in this protocol. The main advantage of tribological testing is that loading parameters can be adjusted freely to simulate in vivo conditions. Furthermore, different testing solutions might be used to investigate the influence of lubrication or pro-inflammatory agents. By using gene expression analysis for cartilage-specific genes and catabolic genes, early changes in the metabolism of articular chondrocytes in response to mechanical loading might be detected.

This protocol describes the preparation, biotribological testing, and analysis of osteochondral cylinders sliding against metal implant material. Outcome measures included in this protocol are metabolic activity, gene expression and histology.

植入物关节软骨滑向金属的生物摩擦学测试与分析

Osteochondral defects in middle-aged patients might be treated with focal metallic implants. First developed for defects in the knee joint, implants are ...

Oxygen-Induced Retinopathy Model for Ischemic Retinal Diseases in Rodents

One of the commonly used models for ischemic retinopathies is the oxygen-induced retinopathy (OIR) model. Here we describe detailed protocols for the OIR model induction and its readouts in both mice and rats. Retinal neovascularization is induced in OIR by exposing rodent pups either to hyperoxia (mice) or alternating levels of hyperoxia and hypoxia (rats). The primary readouts of these models are the size of neovascular (NV) and avascular (AVA) areas in the retina. This preclinical in vivo model can be used to evaluate the efficacy of potential anti-angiogenic drugs or to address the role of specific genes in the retinal angiogenesis by using genetically manipulated animals. The model has some strain and vendor specific variation in the OIR induction which should be taken into consideration when designing the experiments.

Oxygen-induced retinopathy (OIR) can be used to model ischemic retinal diseases such as retinopathy of prematurity and proliferative diabetic retinopathy and to serve as a model for proof-of-concept studies in evaluating antiangiogenic drugs for neovascular diseases. OIR induces robust and reproducible neovascularization in the retina that can be quantified.

罗登斯缺血性视网膜疾病的氧诱导视网膜病变模型

One of the commonly used models for ischemic retinopathies is the oxygen-induced retinopathy (OIR) model. Here we describe detailed protocols for the OIR ...

Induction and Analysis of Oxidative Stress in Sleeping Beauty Transposon-Transfected Human Retinal Pigment Epithelial Cells

Oxidative stress plays a critical role in several degenerative diseases, including age-related macular degeneration (AMD), a pathology that affects ~30 million patients worldwide. It leads to a decrease in retinal pigment epithelium (RPE)-synthesized neuroprotective factors, e.g., pigment epithelium-derived factor (PEDF) and granulocyte-macrophage colony-stimulating factor (GM-CSF), followed by the loss of RPE cells, and eventually photoreceptor and retinal ganglion cell (RGC) death. We hypothesize that the reconstitution of the neuroprotective and neurogenic retinal environment by the subretinal transplantation of transfected RPE cells overexpressing PEDF and GM-CSF has the potential to prevent retinal degeneration by mitigating the effects of oxidative stress, inhibiting inflammation, and supporting cell survival. Using the Sleeping Beauty transposon system (SB100X) human RPE cells have been transfected with the PEDF and GM-CSF genes and shown stable gene integration, long-term gene expression, and protein secretion using qPCR, western blot, ELISA, and immunofluorescence. To confirm the functionality and the potency of the PEDF and GM-CSF secreted by the transfected RPE cells, we have developed an in vitro assay to quantify the reduction of H2O2-induced oxidative stress on RPE cells in culture. Cell protection was evaluated by analyzing cell morphology, density, intracellular level of glutathione, UCP2 gene expression, and cell viability. Both, transfected RPE cells overexpressing PEDF and/or GM-CSF and cells non-transfected but pretreated with PEDF and/or GM-CSF (commercially available or purified from transfected cells) showed significant antioxidant cell protection compared to non-treated controls. The present H2O2-model is a simple and effective approach to evaluate the antioxidant effect of factors that may be effective to treat AMD or similar neurodegenerative diseases.

Induction and Analysis of Oxidative Stress in Sleeping Beauty Transposon-Transfected Human Retinal Pigment Epithelial Cells

We present a protocol for the development and use ofan oxidative stress-model by treating retinal pigment epithelial cells with H2O2, analyzing cell morphology, viability, density, glutathione, and UCP-2 level. It is a useful model to investigate the antioxidant effect of proteins secreted by transposon-transfected cells to treat neuroretinal degeneration.

睡眠美人转座转染人视网膜色素上皮细胞氧化应激的诱导与分析

Oxidative stress plays a critical role in several degenerative diseases, including age-related macular degeneration (AMD), a pathology that affects ~30 ...

Retinal Organoid Induction System for Derivation of 3D Retinal Tissues from Human Pluripotent Stem Cells

Retinal degenerative diseases are the main causes of irreversible blindness without effective treatment. Pluripotent stem cells that have the potential to differentiate into all types of retinal cells, even mini-retinal tissues, hold huge promises for patients with these diseases and many opportunities in disease modeling and drug screening. However, the induction process from hPSCs to retinal cells is complicated and time-consuming. Here, we describe an optimized retinal induction protocol to generate retinal tissues with high reproducibility and efficiency, suitable for various human pluripotent stem cells. This protocol is performed without the addition of retinoic acid, which benefits the enrichment of cone photoreceptors. The advantage of this protocol is the quantification of EB size and plating density to significantly enhance the efficiency and repeatability of retinal induction. With this method, all major retinal cells sequentially appear and recapitulate the main steps of retinal development. It will facilitate downstream applications, such as disease modeling and cell therapy.

Here we describe an optimized retinal organoid induction system, which is suitable for various human pluripotent stem cell lines to generate retinal tissues with high reproducibility and efficiency.

视网膜器官诱导系统，用于从人类多能干细胞中提取3D视网膜组织

Retinal degenerative diseases are the main causes of irreversible blindness without effective treatment. Pluripotent stem cells that have the potential to ...

Retinal Pigment Epithelium Transplantation in a Non-human Primate Model for Degenerative Retinal Diseases

Retinal pigment epithelial (RPE) transplantation holds great promise for the treatment of inherited and acquired retinal degenerative diseases. These conditions include retinitis pigmentosa (RP) and advanced forms of age-related macular degeneration (AMD), such as geographic atrophy (GA). Together, these disorders represent a significant proportion of currently untreatable blindness globally. These unmet medical needs have generated heightened academic interest in developing methods of RPE replacement. Among the animal models commonly utilized for preclinical testing of therapeutics, the non-human primate (NHP) is the only animal model that has a macula. As it shares this anatomical similarity with the human eye, the NHP eye is an important and appropriate preclinical animal model for the development of advanced therapy medicinal products (ATMPs) such as RPE cell therapy.
This manuscript describes a method for the submacular transplantation of an RPE monolayer, cultured on a polyethylene terephthalate (PET) cell carrier, underneath the macula onto a surgically created RPE wound in immunosuppressed NHPs. The fovea-the central avascular portion of the macula-is the site of the greatest mechanical weakness during the transplantation. Foveal trauma will occur if the initial subretinal fluid injection generates an excessive force on the retina. Hence, slow injection under perfluorocarbon liquid (PFCL) vitreous tamponade is recommended with a dual-bore subretinal injection cannula at low intraocular pressure (IOP) settings to create a retinal bleb. 
Pretreatment with an intravitreal plasminogen injection to release parafoveal RPE-photoreceptor adhesions is also advised. These combined strategies can reduce the likelihood of foveal tears when compared to conventional techniques. The NHP is a key animal model in the preclinical phase of RPE cell therapy development. This protocol addresses the technical challenges associated with the delivery of RPE cellular therapy in the NHP eye.

The non-human primate (NHP) is an ideal model for studying human retinal cellular therapeutics due to the anatomical and genetic similarities. This manuscript describes a method for submacular transplantation of retinal pigment epithelial cells in the NHP eye and strategies to prevent intraoperative complications associated with macular manipulation.

非人灵长类动物模型中视网膜色素上皮移植治疗退行性视网膜疾病

Retinal pigment epithelial (RPE) transplantation holds great promise for the treatment of inherited and acquired retinal degenerative diseases. These ...