A MERS-CoV Receptor Decoy

MERS-CoV 受体诱饵

基本信息

批准号：
8981265
负责人：
KEITH WYCOFF
金额：
$ 80.18万
依托单位：
PLANET BIOTECHNOLOGY, INC.
依托单位国家：
美国
项目类别：
财政年份：
2014
资助国家：
美国
起止时间：
2014-06-01 至 2017-07-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8981265
关键词：
Active Sites Affinity Amino Acids Antibodies Binding Biotechnology Camels Case Fatality Rates Cell Surface Proteins Cells Cessation of life Contracts Coronavirus Coronavirus Infections Coronavirus spike protein Country Development Dipeptidyl Peptidases Dose Drug Kinetics Enzyme-Linked Immunosorbent Assay Evaluation Extracellular Domain Fc Immunoglobulins Glucose Half-Life Health Human Hydrolase IgA1 IgA2 IgG1 Immunoglobulin Isotypes Immunoglobulins Infection Laboratories Lead Link Middle East Middle East Respiratory Syndrome Coronavirus Modeling Mus Mutate Mutation Peptide Hydrolases Phase Physiological Processes Planets Plants Polysaccharides Process Production Protein Binding Protein S Proteins Rattus Recombinant Proteins Route Safety Serum Site Surface Syndrome System Testing Toxicology Variant Virus base coronavirus receptor design efficacy testing epidemiology study improved in vivo inhibitor/antagonist intraperitoneal novel therapeutics pandemic disease phase 1 study phase 2 study protective efficacy public health relevance receptor respiratory scale up transmission process

项目摘要

DESCRIPTION (provided by applicant): Middle East respiratory syndrome coronavirus (MERS-CoV) is a newly emerging human health threat with a ~35% case fatality rate. MERS-CoV uses dipeptidyl peptidase 4 (DPP4), a cell surface protein, to enter and infect cells. During our Phase I study, using a transient plant expression system, we produced fusions of human DPP4 and the human immunoglobulin Fc sequences of IgG1, IgA1 and IgA2, to produce "receptor decoys" to block cellular infection with MERS-CoV. We demonstrated that DPP4-Fc binds to the S1 domain of MERS-CoV S protein, and that DPP4-Fc is a more potent inhibitor of MERS-CoV cellular infection than soluble DPP4. We showed that a DPP4-Fc fusion based on IgA1 might possibly be more effective than one based on IgG1. In addition, we demonstrated that binding and virus neutralization could be improved by more than 10-fold by modifying a single amino acid where human DPP4 and MERS-CoV spike protein contact. DPP4-Fc is also expected to have superior pharmacokinetics, as Fc will confer a long circulating half-life and the ability to be delivered to airway mucosal surfaces, the site of MERS-CoV infection. In a phase II study, we will produce new DPP4-Fc constructs to improve DPP4's affinity for MERS-CoV spike protein, and eliminate DPP4's peptidase activity by mutating the active site. We will optimize new constructs to improve expression in plants and to produce DPP4-Fc with human-like N-linked glycans. New DPP4-Fc fusions will be ranked for MERS-CoV spike protein-binding by ELISA and tested for the ability to neutralize MERS-CoV infection in susceptible cells. The best performing DPP4-Fc variants will be tested for protective efficacy in a mouse MERS model, evaluating both intraperitoneal and intranasal routes of administration. We will scale up production and purification of our lead molecule to purify 7 grams of DPP4-Fc, which will be used for a pilot 2-week repeat-dose safety/toxicology study in rats. We will evaluate safety and quantify DPP4-Fc in serum to obtain pharmacokinetic parameters. We will also screen for anti-DPP4-Fc antibodies in these studies.

描述（由适用提供）：中东呼吸综合征冠状病毒（MERS-COV）是新出现的人类健康威胁，病例死亡率约为35％。 MERS-COV使用二肽基肽4（DPP4），一种细胞表面蛋白，进入和感染细胞。在我们研究期间，使用瞬态植物表达系统，我们产生了人类DPP4的融合以及IgG1，IgA1和IgA2的人类免疫球蛋白FC序列，以产生“受体诱饵”，以用MERS-COV阻断细胞感染。我们证明了DPP4-FC与MERS-COV S蛋白的S1结构域结合，而DPP4-FC比固体DPP4更重要的MERS-COV细胞感染抑制剂。我们表明，基于IGA1的DPP4-FC融合可能比基于IgG1的DPP4-FC更有效。此外，我们证明了通过修饰人类DPP4和MERS-COV尖峰蛋白接触的单个氨基酸，可以通过修饰单个氨基酸来改善结合和病毒中和。 DPP4-FC也有望具有出色的药代动力学，因为足球俱乐部将召集长期循环的半衰期，并能够将其传递到MERS-COV感染的地点（MERS-COV感染）。在II期研究中，我们将生成新的DPP4-FC构建体，以改善DPP4对MERS-COV峰值蛋白的亲和力，并通过突变活性位点来消除DPP4的肽活性。我们将优化新的构建体以改善植物中的表达，并用类似人类的N连接聚糖产生DPP4-FC。新的DPP4-FC融合将通过ELISA对MERS-COV尖峰蛋白结合进行排名，并测试了易感细胞中MERS-COV感染的能力。最佳性能DPP4-FC变体将在小鼠MERS模型中进行保护效率，以评估腹膜内和鼻内给药途径。我们将扩大铅分子的生产和纯化，以净化7个DPP4-FC的图，该图将用于大鼠2周的重复剂量安全/毒理学研究。我们将评估血清中的安全性并量化DPP4-FC以获得药代动力学参数。在这些研究中，我们还将筛选抗DPP4-FC抗体。