HTRA1 as a Therapeutic Target in the Treatment of Wet AMD

HTRA1 作为治疗湿性 AMD 的治疗靶点

• 批准号: 9302436
• 负责人: PETER X SHAW
• 金额: $ 34.88万
• 依托单位: UNIVERSITY OF CALIFORNIA, SAN DIEGO
• 依托单位国家: 美国
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-08-01 至 2020-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9302436
• 关键词: 10q26; Address; Affinity; Age related macular degeneration; Alleles; Angiogenic Factor; Animals; Antibodies; Apolipoprotein E; Area; Binding; Biochemistry; Blood Vessels; Bruch' s basal membrane structure; Cells; Choroid; Choroidal Neovascularization; Chromosomes; Chromosomes, Human, Pair 10; Clinical; Complement Factor H; Complex; Coupled; Data; Development; Disease; Down-Regulation; Elderly; Environmental Risk Factor; Event; Evolution; Excision; Extracellular Matrix; Eye; Family; Foundations; Gene Expression; Genetic; Genetic Predisposition to Disease; Genetic Risk; Genotype; Growth; Growth Factor; Haplotypes; High temperature of physical object; Histopathology; Human; Image; Immunoglobulin Fragments; In Vitro; Incidence; Inflammation; Injectable; Injection of therapeutic agent; Journals; Knock-out; Knockout Mice; Lasers; Lead; Link; Modeling; Molecular; Monoclonal Antibodies; Morphology; Mus; Mutation; Oxidative Stress; Pathogenicity; Pathologic; Pathology; Patients; Penetrance; Peptide Hydrolases; Peptides; Predisposition; Process; Promoter Regions; Proteins; Publishing; Research; Retina; Retinal; Retinal Neovascularization; Risk; Role; Scaffolding Protein; Serine Protease; Signal Transduction; Single Nucleotide Polymorphism; Smoking; Structure of retinal pigment epithelium; Technology; Technology Transfer; Testing; Therapeutic; Tissues; Transforming Growth Factor beta; Transgenic Organisms; United States; Up-Regulation; Vascular Endothelial Growth Factors; Vascularization; Visual impairment; Work; adeno-associated viral vector; age related; angiogenesis; assault; cytotoxicity; experimental study; gene therapy; genetic risk factor; genetic variant; growth differentiation factor 6; laser photocoagulation; member; mouse model; neovascular; neovascularization; neutralizing antibody; novel; novel strategies; novel therapeutic intervention; novel therapeutics; oxidized low density lipoprotein; polyclonal antibody; public health relevance; response; risk variant; scaffold; stressor; subretinal injection; superoxide dismutase 1; therapeutic target; vascular abnormality

 DESCRIPTION (provided by applicant): Age-related macular degeneration (AMD) is the most common cause of visual impairment among the elderly in the United States. This research aims to find its cause at the molecular level. In AMD, like many other age- related diseases, both genetic risk factors and environmental assaults are key contributors. A prominent genetic change in chromosome 10 has been previously identified to be strongly associated with susceptibility to AMD. This genetic variant is located in the promoter region of a protein, called the high temperature requirement factor A1 (HTRA1). This disease genotype results in an increased expression of HTRA1. We also performed functional studies using the HTRA1 knockout (htra1-/-) mice, and found that the loss of HTRA1 leads to decreased retinal vascular development along with a significant down-regulation of vascular endothelial growth factor (VEGF) expression. Conversely, our experiments show that increased expression of HTRA1 in RPE leads to an AMD-like pathology and elevated VEGF expression. High VEGF stimulates abnormal vascular growth in the retinal pigment epithelium (RPE) layer and Bruch's membrane of the eye, which can result in wet AMD. One of our more recent studies, published in the Journal of Biological Chemistry revealed that the up- regulation of VEGF by HTRA1 is inversely correlated to the down-regulation of a member of the tissue growth factor-beta (TGF- family called Growth Differentiation Factor 6 (GDF6). The long term objectives of this proposal are to elucidate the molecular mechanism by which HTRA1 contributes to an increased risk of AMD, and to develop potential therapies for AMD. Our hypothesis is that oxidative stress can induce a higher level expression of HTRA1, which contributes to the risk of AMD by regulating signal transduction, vascular development, angiogenesis, and extracellular matrix. Guided by this hypothesis, we propose to conduct studies in following areas: 1) We will investigate how genetic variants can influence the RPE cells to respond to oxidative stress for the expression of angiogenic factors and HTRA1. 2) We will determine whether HTRA1 and oxidative stress impact retinal and choroidal vasculature and pathology. We will also try to determine whether removal of HTRA1 in mouse is protective to oxidative stress enhanced neovascularization in htra1-/- mice and control mice, which will be used to examine morphology and gene expression in the retina and choroid. 3) We will utilize our cloned monoclonal antibodies against HTRA1 to investigate their therapeutic potential by tissue-specific delivery into the RPE cells, aiming to inhibit the abnormal vascular growth. In this scenario, the selected antibody will be converted into a single chain peptide, which will be further "evolved" to maximize its affinity to HTRA1 and ability to inhibit the protease activity while minimizing its cytotoxicity using a novel protein scaffold evolution technology. A gene therapy strategy will be used to deliver such antibodies into the RPE cells and test their ability to inhibit choroidal neovascularization (CNV) aiming to develop a novel approach to treat wet AMD.

 描述（由适用提供）：与年龄相关的黄斑变性（AMD）是美国较早的视觉障碍的最常见原因。这项研究旨在在分子水平上找到其原因。在AMD中，像许多其他与年龄有关的疾病一样，遗传危险因素和环境攻击都是关键因素。先前已确定为10染色体的显着遗传变化与对AMD的敏感性密切相关。该遗传变异位于蛋白质的启动子区域中，称为高温需求因子A1（HTRA1）。该疾病基因型导致HTRA1的表达增加。我们还使用HTRA1基因敲除（HTRA1 - / - ）小鼠进行了功能研究，发现HTRA1的丧失导致视网膜血管发育降低，并显着下调血管内皮生长因子（VEGF）表达。相反，我们的实验表明，RPE中HTRA1的表达增加会导致AMD样病理和VEGF表达升高。高VEGF刺激视网膜色素上皮（RPE）层的异常血管生长和眼睛的Bruch膜，这可能导致湿AMD。我们最近发表在《生物化学杂志》上的一项研究表明，htra1对VEGF的上调与对组织生长因子-BETA的成员的下调成反比（称为生长分化因子6的TGF-thement）的下调（GDF6）（GDF6）（GDF6）。我们的假设的潜在疗法是，氧化应激可以诱导HTRA1的更高水平的表达，从而有助于通过控制信号转换，血管生成，血管生成，血管生成和细胞外基质的风险。和htra1。 2）我们将确定HTRA1和氧化应激是否影响残留和脉络膜脉管系统和病理。我们还将尝试确定小鼠中HTRA1的去除是否受到HTRA1 - / - 小鼠和对照小鼠的氧化应激增强的氧化应激增强，该氧化应为检查视网膜和脉络膜中的形态和基因表达。 3）我们将利用针对HTRA1的克隆单克隆抗体来研究其通过组织特异性递送到RPE细胞中的治疗潜力，旨在抑制异常的血管生长。在这种情况下，选定的抗体将转化为单个链肽，该肽将进一步“进化”，以最大化其与HTRA1的亲和力，并使用新型的蛋白质支架进化技术最小化其细胞毒性，同时抑制蛋白酶活性的能力。一种基因治疗策略将用于将这种抗体输送到RPE细胞中，并测试其抑制脉络膜新生血管形成（CNV）的能力（CNV），旨在开发一种治疗湿AMD的新方法。