Bifunctional antibodies with targeted CNS delivery against West Nile virus

具有针对西尼罗河病毒的靶向中枢神经系统递送的双功能抗体

• 批准号: 8366722
• 负责人: Qiang Chen
• 金额: $ 20.42万
• 依托单位: ARIZONA STATE UNIVERSITY-TEMPE CAMPUS
• 依托单位国家: 美国
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-06-01 至 2014-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8366722
• 关键词: Address; Adverse effects; Affect; Affinity; Agrobacterium; Antibodies; Antibody-Dependent Enhancement; Binding; Biomass; Bispecific Antibodies; Blood - brain barrier anatomy; Brain; C57BL/6 Mouse; Cessation of life; Characteristics; Chinese Hamster Ovary Cell; Communicable Diseases; Complement 1q; Complement-Dependent Cytotoxicity; Conscious; Cyclic GMP; Data; Development; Disease; Dose; E protein; Elderly; Encephalitis; Endocytosis; Endothelial Cells; Engineering; Ensure; Epitopes; Fc Receptor; Future; Generations; Grant; Hamsters; Human; Immunocompromised Host; In Vitro; Infection; Inflammation; Inflammatory; Intravenous; Licensing; Link; Meningitis; Modeling; Mus; Neuraxis; Pattern; Peripheral; Permeability; Phase; Plant Proteins; Plants; Polysaccharides; Process; Production; Proteins; Rattus; Reagent; Regulation; Risk; Rodent; Route; Safety; Survival Rate; Technology; Testing; Therapeutic; Transferrin Receptor; Transgenic Organisms; Variant; Vertebrates; Virus Diseases; West Nile virus; adverse outcome; base; clinical care; combat; cost; cost effective; env Gene Products; glycosylation; human INSR protein; improved; intraperitoneal; large scale production; mouse model; neoplastic; nervous system disorder; novel therapeutics; receptor; scale up; theories; transcytosis; vector

DESCRIPTION (provided by applicant): West Nile Virus (WNV) causes infection in the central nervous system (CNS) in several vertebrate animal species. Humans infected with WNV can develop meningitis and encephalitis, and the elderly and immunocompromised are at greatest risk for severe neurological disease and death. New threats of WNV globally and the lack of available treatments warrant studies to develop effective therapeutics and production technologies that can rapidly transfer candidate therapies into the clinical care setting in a cost conscious manner. We recently developed a plant-derived humanized MAb with promising therapeutic potential, with a desired human N-linked glycosylation pattern. This MAb (hE16) binds to a highly conserved epitope on the envelope protein of virtually all isolates worldwide and shows promising post-exposure therapeutic activity. Nonetheless, our studies show that peripheral delivery of hE16 has a limited window of efficacy in rodents: administration of a single dose of hE16 through an intravenous or intraperitoneal route at day 5 post infection or earlier improves survival rates. In comparison, delivery of hE16 directly into the brain at day 6 after infection improved protection against lethal WNV infection in hamsters. Our preliminary data show that a genetically engineered bifunctional MAb variant of hE16 (TfR-Bif) with the potential for enhanced crossing of the blood-brain barrier (BBB) can be expressed in CHO cells or plants. TfR-Bif retains its ability to bind and neutralize WNV, but importantly gains the ability to bind transferrin receptor (TfR) and endocytose into mouse brain endothelial cells. In the R21 phase of this grant, we will use the mouse TfR-specific TfR-Bif as a proof-of-principle in a mouse model of WNV infection. We will test the hypothesis that TfR-Bif can achieve higher levels in the CNS and extends the window of treatment against WNV encephalitis. To address critical safety issues in the brain, we will also identify TfR-Bif glycoforms that offer full bifunctionality with limited or specific Fc receptor (Fc?R) or C1q binding to eliminate potential antibody-dependent enhancement (ADE) of virus infection or pathogenic inflammation. In the R33 phase, we will develop an analogous bifunctional MAb with human therapeutic potential and test if plants provide distinctive advantages in safety, production cost, and scalability for large-scale production under cGMP. In addition to generating novel therapeutic reagents for WNV, this collaborative study will provides a platform for delivery of MAbs to the CNS, which should be applicable to the treatment of other infectious, inflammatory, or neoplastic diseases in the CNS. PUBLIC HEALTH RELEVANCE: This study will generate novel therapeutic reagents for West Nile virus, provide a technology for delivery of therapeutics to the brain, and develop a cost-effective and scalable production technology using plants for protein therapeutics. Such technologies can be applied in the future to combat emerging infectious or non- infectious diseases or bioterrorist threats.

描述(申请人提供)：西尼罗河病毒(WNV)会导致几种脊椎动物的中枢神经系统(CNS)感染。感染西尼罗河病毒的人会患上脑膜炎和脑炎，老年人和免疫功能受损的人患严重神经疾病和死亡的风险最大。西尼罗河病毒在全球范围内的新威胁以及现有治疗方法的缺乏需要进行研究，以开发有效的治疗方法和生产技术，以便以有成本意识的方式迅速将候选治疗方法转移到临床护理环境中。我们最近开发了一种植物来源的人源化单抗，具有良好的治疗潜力，具有理想的人类N-连接糖基化模式。这种单抗(HE16)与世界各地几乎所有分离株的包膜蛋白上的高度保守的表位结合，并显示出良好的暴露后治疗活性。尽管如此，我们的研究表明，外周注射hE16对啮齿动物的疗效窗口有限：单次给药 在感染后第5天或更早通过静脉或腹膜途径注射hE16可提高存活率。相比之下，在感染后第6天直接将hE16送入大脑可以改善对金黄地鼠致命的西尼罗河病毒感染的保护。我们的初步数据显示，具有增强血脑屏障(BBB)穿透能力的hE16基因工程双功能单抗变体(TFR-Bif)可以在CHO细胞或植物中表达。TFR-Bif保留了结合和中和西尼罗河病毒的能力，但重要的是获得了将转铁蛋白受体(TFR)和内毒素结合到小鼠脑内皮细胞的能力。在这项资助的R21阶段，我们将使用小鼠TFR特异性TFR-Bif作为WNV感染小鼠模型的原则证明。我们将验证TFR-BIF可以在中枢实现更高水平的假设，并延长针对WNV脑炎的治疗窗口。为了解决大脑中的关键安全问题，我们还将确定具有与有限或特定Fc受体(Fc？R)或C1q结合的全双功能的TFR-Bif糖体，以消除潜在的病毒感染或致病性炎症的抗体依赖增强(ADE)。在R33阶段，我们将开发一种类似的具有人类治疗潜力的双功能单抗，并测试植物是否在安全性、生产成本和可扩展性方面为cGMP下的大规模生产提供了独特的优势。除了为西尼罗河病毒产生新的治疗试剂外，这项合作研究还将提供一个将单抗输送到中枢神经系统的平台，这应该适用于中枢神经系统其他感染性、炎症性或肿瘤性疾病的治疗。 公共卫生相关性：这项研究将产生西尼罗河病毒的新型治疗试剂，提供一种将治疗药物输送到大脑的技术，并开发一种利用植物进行蛋白质治疗的成本效益和可扩展的生产技术。此类技术可在未来应用于抗击新出现的传染病或非传染性疾病或生物恐怖主义威胁。