Retinal tissue derived from human pluripotent stem cells for vision restoration

摘自原SBIR第二阶段 该项目将测试人类胚胎干细胞来源的3-D视网膜组织，移植到2岁以下的视网膜下腔 在一项长达12个月的纵向研究中，建立了光感受器(PR)变性的动物模型。我们会 使用带有CRX突变的早发性RD的大眼睛动物模型(Rdy Abyssiian猫)和免疫... PR变性缺陷型SD-Foxn1 TG(S334ter)3Lav(RD裸鼠)。眼下的目标是 显示移植物的存活、分层、成熟以及结构和突触的整合。 受者视网膜和视力改善6-12个月，并为 将这种技术转化为治疗公关死亡所致失明的疗法。首要目标是 在视网膜色素变性(RP)患者的试点临床试验中评估这项技术，RP是一种孤儿疾病， 快速跟踪FDA的批准。 失明是美国人的一个主要健康问题，影响生活质量，并具有很高的经济和 沉重的情感负担。与光感受器退化相关的两种主要视网膜疾病是RP 和干性老年性黄斑变性(AMD)。目前迫切需要寻找新的治疗方法。 基于光感受器替代的RP和AMD。过去15-20年的研究表明，一件 退化的哺乳动物视网膜可以被健康的胎儿视网膜组织取代，这可以改善视力。 研究表明，移植的胎儿视网膜会在受体视网膜上完成分化、突触 神经节细胞神经元，并重新建立与视觉皮质的连接。人胎视网膜组织 药物的供应非常有限，从伦理上讲，它在治疗中的临床应用是不可接受的。 BioTime假设6-8周大的人类胚胎干细胞衍生的3-D视网膜组织将整合 在结构和突触上进入退化的受体视网膜，并改善晚期糖尿病动物的视力 研发。我们预测，hESC-3D视网膜组织移植的积极治疗作用将在 具有RD的动物模型将使我们能够将这项技术应用于RP患者的临床试验。我们有 已经开发出hESC-3D视网膜组织，并证明它携带一层RPE，PR，二级 神经元和神经节细胞，具有轴突发生、突触形成和进行性 有电活动。我们还报道了它能改善RP和失明大鼠动物模型的视力，并 激活上丘。 我们建议在一个“大眼睛”动物模型中进行体内测试，该动物模型是一种失明的RD(Rdy Cat)动物模型。 SD-Foxn1 TG(S334ter)3Lav(RD裸鼠)大鼠合并RD的队列统计评价其可行性 RP患者的治疗。 在目标1(生物时间)，我们将扩大从cGMP级hESCs和hESCs生产hESC-3D视网膜组织 使用FDA标准对几个批次进行评估。 in Aim 2(UCI)，我们将对失明大鼠进行视网膜下移植，并评估视力改善和移植- 主机连接。 在目标3(MSU)，我们将为RDY/+猫进行视网膜下移植并评估视力改善和 移植物-宿主连接。 结果和程序将被整合到临床方案中，以使导致失明的临床试验成为可能 公关退化所致。

Abstract from the original SBIR Phase II This project will test human embryonic stem cell-derived 3-D retinal tissue transplanted in subretinal space of 2 animal models with photoreceptor (PR) degeneration in a longitudinal study lasting for up to 12 months. We will use a large-eye animal model of early-onset RD with a Crx mutation (Rdy Abyssinian cats) and immuno- deficient rats with PR degeneration SD-Foxn1 Tg(S334ter)3Lav (RD nude). The immediate goal is to demonstrate the survival, lamination, maturation, and structural and synaptic integration of grafts with the recipient retina, and improvement in vision by 6-12 months, and to generate standard operating procedures for transforming such technology into therapy to treat blindness caused by PR death. The overarching goal is to evaluate this technology in pilot clinical trials in patients with retinitis pigmentosa (RP), an orphan disease with fast track FDA approval. Blindness is a major health concern among Americans, affecting quality of life and with a high financial and heavy emotional burden. The two major retinal diseases associated with photoreceptor degeneration are RP and dry age-related macular degeneration (AMD). There is a critical and urgent need to find new treatments of RP and AMD based on photoreceptor replacement. The research in the past 15-20 years indicates that a piece of degenerating mammalian retina can be replaced with healthy fetal retinal tissue, which can improve vision. The research shows that grafted fetal retina will complete differentiation, synapse on the recipient retinal ganglion cell neurons, and re-establish connectivity with the visual cortex. Human fetal-derived retinal tissue supply is very limited, and its clinical use in therapy is ethically not acceptable. BioTime hypothesizes that 6-8-week old human embryonic stem cell-derived 3-D retinal tissue will integrate structurally and synaptically into the degenerating recipient retina and improve vision in animals with advanced RD. We predict that demonstrating positive therapeutic impact of hESC-3D retinal tissue grafting in a “large eye” animal model with RD will enable us to move this technology to pilot clinical trials in RP patients. We have already developed hESC-3D retinal tissue and demonstrated that it carries a layer of RPE, PRs, second order neurons and ganglion cells, is capable of axonogenesis, synaptogenesis and becomes progressively electrically active. We also reported that it improves vision in a rat animal model with RP and blindness and activates superior colliculus. We propose to do in vivo testing in a “large eye” animal model of RD (Rdy cats) with blindness, and in a large cohort of SD-Foxn1 Tg(S334ter)3Lav (RD nude) rats with RD to statistically evaluate the feasibility of this therapy in RP patients.  In Aim 1 (BioTime), we will scale-up production of hESC-3D retinal tissue from cGMP-grade hESCs and evaluate several lots using FDA criteria.  In Aim 2 (UCI), we will do subretinal grafting into blind rats and evaluate vision improvements and graft- host connectivity.  In Aim 3 (MSU), we will do subretinal grafting into Rdy/+ cats and also evaluate vision improvements and graft-host connectivity. The results and procedures will be integrated into clinical protocols to enable clinical trials of blindness caused by PR degeneration.