Preclinical and Clinical Development of Treatment for X-linked Retinoschisis

X连锁视网膜劈裂治疗的临床前和临床进展

• 批准号: 8157962
• 负责人: Paul Sieving
• 金额: $ 56.87万
• 依托单位: NATIONAL INSTITUTE ON DEAFNESS AND OTHER COMMUNICATION DISORDERS
• 依托单位国家: 美国
• 资助国家: 美国
• 起止时间: 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/8157962
• 关键词: Clinical; X-Linked Retinoschisis; pre-clinical; therapy development

This laboratory is titled Translational Research, as we use inherited retinal degenerations identified in the clinic as both a source of clues about retinal function and dysfunction and a target for research in therapeutic intervention. Current efforts focus on human X-linked juvenile retinoschisis (XLRS). XLRS is an inherited disease and is a leading cause of juvenile macular degeneration in human males. It is due to mutations in the retinoschisin (RS) gene found on the X chromosome. We are working to understand the disease mechanisms that bring about retinal structural changes and neuronal synaptic signaling deficiency in a mouse model created in this laboratory section. At the same time, we are developing gene transfer therapy using a viral vector to supply a normal copy of the retinoschisin gene to the retina of patients in which it is defective. . Our current understanding is based on a study of human affected patients and on analysis of the XLRS mouse model. We have probed the biochemistry and sub-cellular localization of the retinoschisin protein and have localized it to particular cell membrane sites of photoreceptors and synapses and measured changes in key membrane proteins in synapses. We discovered molecular interactions between retinoschisin and photoreceptor membrane phospholipids biochemically and with atomic force microscopy that may explain its role in neuronal structure and retinal signaling. We cloned and characterized the human gene promoter region and have identified the key regulatory sites. We characterized the biochemical consequences of certain human mutations in the RS gene, and showed that they lead to an absence of the protein. Detailed study of long-term disease progression in the XLRS mouse revealed significant correlations between degenerative structural changes and functional neuronal signaling abnormalities. Such studies currently are not possible in human and provide us better understanding of disease mechanisms and give clues on designing appropriate endpoint metrics for eventual human clinical trial. We showed retinal rescue of structure and function in the XLRS mouse by viral (AAV) vector retinoschisin gene transfer, and we are now characterizing appropriate intervention times in disease progression, doses and other parameters that lead to success or failure of gene transfer. We are also disigning and preparing a human AAV- retinoschisin gene transfer experiment. Clinical protocol: Clinical and Genetic Studies of X-Linked Juvenile Retinoschisis ClinicalTrials.gov Identifier: NCT00055029 The objectives of this registry are to understand the nature of the XLRS disease in order to develop appropriate treatments by characterizing the anatomical and functional characteristics of retinoschisis and ultimately generate a well-documented genotype-phenotype correlation map. A minimum of 100 males diagnosed with X-linked retinoschisis will undergo clinical examination and have their blood drawn for genotyping. Blood will also be drawn from available and consenting mothers of affected males. An eye examination will be performed and blood drawn from any symptomatic available and consenting female family members. A maximum of 500 affected males and family members may be enrolled. Sites outside of NIH are participating as referral centers to accumulate the cohort.

该实验室名为“转化研究”，因为我们使用临床中发现的遗传性视网膜变性作为有关视网膜功能和功能障碍的线索来源，以及治疗干预研究的目标。 目前的工作重点是人类 X 连锁青少年视网膜劈裂症 (XLRS)。 XLRS 是一种遗传性疾病，是人类男性青少年黄斑变性的主要原因。这是由于 X 染色体上的视网膜裂素 (RS) 基因突变造成的。我们正在努力了解在本实验室部分创建的小鼠模型中引起视网膜结构变化和神经元突触信号传导缺陷的疾病机制。与此同时，我们正在开发基因转移疗法，使用病毒载体向有缺陷的患者的视网膜提供正常的视网膜劈裂素基因拷贝。 。 我们目前的理解基于对人类受影响患者的研究和 XLRS 小鼠模型的分析。我们探究了视黄体分裂素蛋白的生物化学和亚细胞定位，并将其定位到光感受器和突触的特定细胞膜位点，并测量了突触中关键膜蛋白的变化。我们通过生物化学和原子力显微镜发现了视网膜裂素和光感受器膜磷脂之间的分子相互作用，这可以解释其在神经元结构和视网膜信号传导中的作用。我们克隆并表征了人类基因启动子区域，并确定了关键的调控位点。我们表征了 RS 基因中某些人类突变的生化后果，并表明它们导致了该蛋白质的缺失。 对 XLRS 小鼠长期疾病进展的详细研究揭示了退行性结构变化与功能性神经元信号异常之间的显着相关性。此类研究目前在人类中是不可能的，可以让我们更好地了解疾病机制，并为最终的人类临床试验设计适当的终点指标提供线索。我们展示了通过病毒（AAV）载体视网膜劈裂素基因转移对 XLRS 小鼠视网膜结构和功能的拯救，并且我们现在正在确定疾病进展、剂量和其他导致基因转移成功或失败的参数的适当干预时间。我们还正在设计和准备人类 AAV-retinoschisin 基因转移实验。 临床方案： X连锁青少年视网膜劈裂症的临床和遗传学研究 ClinicalTrials.gov 标识符：NCT00055029 该登记的目的是了解 XLRS 疾病的性质，以便通过表征视网膜劈裂的解剖和功能特征来开发适当的治疗方法，并最终生成有据可查的基因型-表型相关图。至少 100 名被诊断患有 X 连锁视网膜劈裂症的男性将接受临床检查并抽血进行基因分型。还将从受影响男性的可用且同意的母亲处抽取血液。将进行眼部检查，并从任何有症状且同意的女性家庭成员中抽血。最多可招募 500 名受影响的男性和家庭成员。 NIH 以外的站点正在作为转诊中心参与以积累队列。