Targeting Viral Envelope Glycoproteins with Synthetic Antibodies

用合成抗体靶向病毒包膜糖蛋白

• 批准号: 7952441
• 负责人: Jonathan R. Lai
• 金额: $ 41.5万
• 依托单位: ALBERT EINSTEIN COLLEGE OF MEDICINE
• 依托单位国家: 美国
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-07-01 至 2015-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7952441
• 关键词: Adopted; Affinity; Antibodies; Antibody Affinity; Antibody Formation; Antigens; Antiviral Agents; B cell repertoire; Binding; Biochemical; Blocking Antibodies; Cell membrane; Collaborations; Complementarity Determining Regions; Crystallization; DNA Sequence Rearrangement; Development; Diagnostics Research; Dissection; Elements; Endosomes; Epitopes; Exhibits; Glycoproteins; Goals; HIV-1; Humoral Immunities; Immunization; Immunoglobulin Fragments; Immunology; Immunotherapeutic agent; Immunotherapy; Influenza; Investigation; Libraries; Light; Membrane; Membrane Fusion; Membrane Glycoproteins; Methods; Microbiology; Molecular Conformation; Monoclonal Antibodies; Mutagenesis; Oligonucleotides; Pathway interactions; Peptides; Phage Display; Play; Process; Reagent; Role; Scanning; Secondary to; Source; Specificity; Structure; Technology; Testing; Therapeutic; Therapeutic Agents; Vaccination; Vaccine Design; Vaccines; Viral; Viral Antibodies; Viral Antigens; Virus; Virus Diseases; Work; antibody engineering; base; combinatorial; cost; design; influenzavirus; insight; neutralizing antibody; new technology; novel; novel virus; progenitor; public health relevance; scaffold; tool; vaccine development; virus development

DESCRIPTION (provided by applicant): Monoclonal antibodies directed against the envelope glycoproteins of membrane viruses such as human immunodeficiency virus type 1 (HIV-1), influenza, and ebolavirus are essential reagents for deciphering mechanisms of viral entry, and identifying epitopes for immunotherapy or vaccine development. Recent work in antibody engineering has demonstrated that specific, high-affinity antibodies can be isolated from simple phage display libraries in which diversity at the antibody complementarity determining regions (CDRs) is encoded by designed, synthetically-derived oligonucleotides ('synthetic antibodies'). Therefore, the synthetic antibody approach circumvents many limitations of traditional antibody isolation methods thereby expanding the scope and specificity with which antigens may be targeted. The overall goal of this proposal is to develop enabling synthetic antibody technologies for applications in the study of viral membrane fusion. In Aim 1, we propose to develop synthetic antibody libraries focused toward viral antigens based on the promiscuous germline segment VH1-69. Many viral antibodies borne from this progenitor exhibit similar modes of interaction with their viral antigens, suggesting that VH1-69 could serve as a scaffold for development of virus- specific synthetic antibody libraries. We will produce VH1-69-based synthetic antibody libraries and screen them against viral targets to evaluate this hypothesis. In Aim 2, we propose to identify conformation-specific antibodies that target the membrane-proximal external region (MPER) of HIV-1 gp41. The MPER is the target of several broadly neutralizing antibodies (NAbs) and therefore the subject of intense investigation for vaccine development. We will identify synthetic antibodies against structurally-constrained MPER peptides, and then characterize neutralization potency of these antibodies to gain insight into the role of MPER epitope conformation on inhibition of membrane fusion. In Aim 3, we propose to isolate synthetic antibodies against the putative fusion intermediates of ebolavirus GP1 and GP2. In comparison to HIV-1 and influenza, relatively few antibodies against GP1 and GP2 have been isolated which has greatly impeded mechanistic understanding of membrane fusion for this virus. Our approach will overcome limitations of other antibody isolation methods that have failed to produce GP1- or GP2-specific antibodies, and yield novel reagents for dissection of fusion intermediates and potential immunotherapeutics. PUBLIC HEALTH RELEVANCE: Monoclonal antibodies have been an important source of therapeutic, diagnostic, and research reagents. Recent technological advances in antibody isolation methods have greatly expanded capabilities for isolation of antibodies. We are using this new technology to identify novel antibodies against viral targets. This work will provide new tools to understand viral infection and how this process can be inhibited by therapeutic agents or vaccines.

描述（由申请人提供）：针对人类免疫缺陷病毒 1 型 (HIV-1)、流感病毒和埃博拉病毒等膜病毒包膜糖蛋白的单克隆抗体是破译病毒进入机制以及识别免疫治疗或疫苗开发表位的重要试剂。抗体工程领域的最新研究表明，可以从简单的噬菌体展示文库中分离出特异性高亲和力抗体，其中抗体互补决定区 (CDR) 的多样性由设计的、合成衍生的寡核苷酸（“合成抗体”）编码。因此，合成抗体方法规避了传统抗体分离方法的许多限制，从而扩大了抗原可靶向的范围和特异性。该提案的总体目标是开发用于病毒膜融合研究的合成抗体技术。在目标 1 中，我们建议开发基于混杂种系片段 VH1-69 的针对病毒抗原的合成抗体库。从该祖细胞产生的许多病毒抗体表现出与其病毒抗原相似的相互作用模式，表明VH1-69可以作为开发病毒特异性合成抗体库的支架。我们将产生基于 VH1-69 的合成抗体文库，并针对病毒靶点对其进行筛选，以评估这一假设。在目标 2 中，我们建议鉴定针对 HIV-1 gp41 的近膜外部区域 (MPER) 的构象特异性抗体。 MPER 是几种广泛中和抗体 (NAb) 的靶标，因此是疫苗开发中深入研究的主题。我们将鉴定针对结构受限的 MPER 肽的合成抗体，然后表征这些抗体的中和效力，以深入了解 MPER 表位构象对膜融合抑制的作用。在目标 3 中，我们建议分离针对假定的埃博拉病毒 GP1 和 GP2 融合中间体的合成抗体。与 HIV-1 和流感相比，分离出的针对 GP1 和 GP2 的抗体相对较少，这极大地阻碍了对该病毒膜融合机制的理解。我们的方法将克服其他抗体分离方法无法产生 GP1 或 GP2 特异性抗体的局限性，并产生用于解剖融合中间体和潜在免疫治疗的新型试剂。 公共卫生相关性：单克隆抗体一直是治疗、诊断和研究试剂的重要来源。抗体分离方法的最新技术进步极大地扩展了抗体分离的能力。我们正在使用这项新技术来识别针对病毒靶标的新型抗体。这项工作将为了解病毒感染以及治疗剂或疫苗如何抑制这一过程提供新的工具。