Development Structure and Function of Broadly Neutralizing anti-HIV Antibodies

广泛中和抗HIV抗体的开发结构和功能

• 批准号: 8786046
• 负责人: Pamela J Bjorkman
• 金额: $ 210.03万
• 依托单位: CALIFORNIA INSTITUTE OF TECHNOLOGY
• 依托单位国家: 美国
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-02-10 至 2016-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8786046
• 关键词: AIDS/HIV problem; Abbreviations; Amino Acids; Animals; Antibodies; Antibody Specificity; Antibody-mediated protection; Antigens; Autologous; Automation; Binding; Binding Sites; Biochemical; Bioinformatics; Biological Assay; Blood Circulation; Cells; Clinical Research; Collaborations; Complex; Core Facility; Data; Development; Enhancing Antibodies; Epidemic; Evaluation; Fc Receptor; Future; Genes; Goals; HIV; HIV Antibodies; HIV Infections; HIV envelope protein; HIV vaccine; HIV-1; Human; Immunization; Immunoglobulin G; In Vitro; Individual; Infection; Infection Control; Infection prevention; Injection of therapeutic agent; Knock-in Mouse; Knowledge; Laboratories; Luciferases; Maintenance; Mediating; Modeling; Monkeys; Monoclonal Antibodies; Mucous Membrane; Mus; Mutation; Nature; Patients; Peripheral Blood Mononuclear Cell; Polysaccharides; Prevention; Program Research Project Grants; Proteins; Recombinant Proteins; Relative (related person); Research; Research Personnel; Resistance; Resistance development; Role; Route; Serological; Serum; Services; Structure; System; Testing; Therapeutic; Transcription Coactivator; Vaccination; Vaccine Design; Vaccines; Variant; Viral; Virus; Work; antibody-dependent cell cytotoxicity; base; combat; design; env Gene Products; gene therapy; improved; in vitro Assay; in vitro activity; in vivo; in vivo Model; insight; interest; mouse model; neutralizing antibody; novel; prevent; protein expression; protein protein interaction; receptor; research study; response; structural biology; success

DESCRIPTION (provided by applicant): This P01 Program Project application seeks to develop insights into mechanisms by which antibodies (Abs) protect against HIV infection to facilitate design of improved Abs and effective immunogens. Development of effective vaccines or delivered Abs to control infection will require understanding of Ab interactions with antigen and with Ab receptors that mediate effector functions. Using knowledge of what Env mutations arise in response to HIV infection in humanized mice allows structural/bioinformatic analyses of which features promote Ab evasion, required information for designing broadly neutralizing antibodies (bNAbs) that are insensitive to common routes of viral evasion. This knowledge will allow optimization of the breadth/potency of bNAbs for passive delivery (both by injection and gene therapy "reverse vaccination") and is required for effective immunogen design for vaccines, thus our project is relevant to both traditional and "reverse" vaccine strategies to combat HIV. To accomplish these goals and to establish basic principles underlying Ab-mediated protection, we will combine the expertise of the Nussenzweig, Ravetch, and Bjorkman laboratories in characterization of HIV bNAbs and humanized mouse models of HIV infection, antibody effector function evaluation and improvement, and the structural biology of Ab-HIV and Ab-receptor interactions. Our proposal comprises three separate, but inter-related and inter-dependent collaborative projects, with the following aims: (1) Test designed bNAbs in a humanized mouse model of HIV infection, sequence resistant HIV strains, evaluate bNAbs for ability to control established HIV infection in humanized mice, and evaluate novel immunogens in a mouse model; (2) Investigate the contributions of Fc effector function to HIV bNAbs in vitro and in vivo, including in a new in vivo mouse model for HIV entry and an AAV-based reverse immunization model in humanized mice; (3) Determine structural correlates of broad/potent neutralization and improved effector functions by solving crystal structures of designed and natural bNAbs complexed with HIV Env proteins and Fc receptors; design and test immunogens for eliciting bNAbs. These projects will be supported by an administrative core and three scientific cores comprising a cell/biochemical automation core to perform automated in vitro HIV neutralization and plate-binding assays, a protein expression core to express and purify recombinant proteins required for functional and structural studies, and an animal services core to generate/maintain mice required for in vivo experiments. RELEVANCE: HIV/AIDS remains a global epidemic with an urgent need for a vaccine and/or new therapies. Our project goals are to discover the mechanisms by which anti-HIV antibodies can prevent or treat infection (through Fab-mediated neutralization and Fc-mediated effector functions) and how HIV can escape through mutation, critical knowledge required for improving natural bNAbs as therapeutics and designing immunogens to elicit bNAbs. Project 1 - Human Antibodies to HIV Project Leader (PL): Nussenzweig, Michel DESCRIPTION (provided by applicant): The vast majority of HIV infected individuals develop antibodies to the virus. In most cases the antibodies only target the autologous strain, but some individuals develop neutralizing serologic responses to a broad range of different viral isolates. These responses are of interest because passive transfer of monoclonal antibodies with broad neutralizing activity to humanized mice or monkeys prevents infection. On the basis of these observations it has been proposed that a vaccine that elicits broadly neutralizing antibodies would be protective against HIV. However, little is known about the nature of the broadly neutralizing response. Only a small number of patients have been studied to date, and the majority of these patients are selected because their serologic activity focuses on the CD4 binding site of the viral envelope spike. The long-term goals of this proposal are to characterize new broadly neutralizing antibodies in terms of their functions in vivo and to understand how HIV-1 develops resistance to these antibodies in vivo. To accomplish these goals we propose three specific aims. First, we will develop an in vivo assay to assess the ability of broadly antibodies to prevent viral entry in mice. HIV neutralization is currently assayed in vitro using TZM-bl cells. The new mouse model will be used to examine the relative efficacy of different monoclonal antibodies and the contribution of innate effector mechanisms to blocking HIV entry in vivo. Second, we will define the basis for development of resistance to broadly neutralizing antibodies in HIV infected humanized mice. We will use the information for structure based rational design approaches to iteratively enhance antibody breadth and potency. The ultimate goal of this part of the proposal is to determine which of the large group of currently available antibodies might be most useful for passive vaccine and immunogen design approaches. Finally, we will evaluate potential immunogens designed using structural and other data in knock-in mice containing human germline antibody precursor genes. Taken together, these experiments should help inform future clinical studies in which neutralizing antibodies might be considered for use in passive therapy or prevention studies and which of their targets would be most useful for immunization strategies. RELEVANCE: Although there is still no vaccine for HIV, a small number of infected individuals develop antibodies that can prevent the infection. The proposed research aims to develop an understanding of these antibodies with the long term goal of being able to elicit them de novo as a component of a vaccine to be used in un-infected individuals.

描述（由申请人提供）： 该P01计划项目的应用程序旨在开发有关抗体（ABS）预防HIV感染以促进改善ABS和有效免疫原理的机制的见解。开发有效的疫苗或递送为控制感染的ABS将需要了解与抗原的AB相互作用以及介导效应子功能的AB受体。利用对人性化小鼠中艾滋病毒感染产生的环境突变的知识可以使结构性/生物信息学分析哪些特征促进AB逃避，这是设计广泛中和的抗体（BNAB）所需的信息，这些抗体（BNAB）对常见的病毒逃避途径不敏感。这些知识将允许对BNAB的广度/效力进行被动递送的广度/效力（无论是注射和基因治疗》“反疫苗接种”），对于有效的免疫原设计疫苗是必需的，因此我们的项目与传统和“反向”疫苗策略均相关。为了实现这些目标并建立AB介导保护的基本原则，我们将结合Nussenzweig，Ravetch和Bjorkman实验室的专业知识，以表征HIV BNABS和HIV HIV感染的人源化鼠标模型，抗体效应器功能评估和改进，以及AB-HIV和AB-HIV和AB-Receptor互动的结构。我们的提案包括三个独立但相互关联和相互依赖的协作项目，其目的是：（1）测试在人源化的HIV感染，抗性HIV菌株的人性化鼠标模型中设计的BNAB，评估BNABS以控制人体化小鼠中已建立的HIV感染的能力，并评估了人体化的新型免疫原菌，并在鼠标模型中评估了新型的免疫原生物； （2）研究FC效应功能对HIV BNAB的体外和体内的贡献，包括在新的体内 用于HIV进入的小鼠模型和人源化小鼠中的基于AAV的反向免疫模型； （3）通过求解与HIV Env蛋白和FC受体复合的设计和天然BNAB的晶体结构，确定广泛/有效中和的结构相关性；设计和测试免疫原料用于引发bnabs。这些项目将由行政核心和三个科学核心支持，其中包括一个细胞/生物化学自动化核心，以执行自动化的体外HIV中和和板块结合测定，这是表达和纯化重组蛋白所需的重组蛋白的蛋白质表达核心，以及为无需生成无需小鼠的动物服务核心即可为In In Iniv Onivo提供的动物服务核心。 相关性：艾滋病毒/艾滋病仍然是一种全球流行病，迫切需要疫苗和/或新疗法。我们的项目目标是发现抗HIV抗体可以预防或治疗感染的机制（通过FAB介导的中和和FC介导的效应子功能）以及HIV如何通过突变逃脱，改善自然BNAB所需的关键知识，以改善自然BNAB作为治疗疗法和设计免疫原子以促进BNABS。 项目1-艾滋病毒的人类抗体 项目负责人（PL）：Nussenzweig，Michel 描述（由申请人提供）：绝大多数受艾滋病毒感染的人会发展为病毒的抗体。在大多数情况下，抗体仅针对自体菌株，但是有些个体对各种不同病毒分离株产生中和血清学反应。这些反应引起了人们的关注，因为对人源化小鼠或猴子具有广泛中和活性的单克隆抗体的被动转移会阻止感染。根据这些观察结果，已经提出，一种广泛中和抗体的疫苗将对HIV进行保护。但是，对广泛中和反应的性质知之甚少。迄今为止，仅研究了少数患者，并且选择了大多数患者，因为它们的血清学活性集中在病毒包膜尖峰的CD4结合位点上。该提案的长期目标是根据其在体内的功能方面表征新的广泛中和抗体，并了解HIV-1如何在体内对这些抗体产生抗性。为了实现这些目标，我们提出了三个具体目标。首先，我们将开发一种体内测定，以评估广泛的抗体防止小鼠病毒进入的能力。目前使用TZM-BL细胞在体外测定HIV中和。新的小鼠模型将用于检查不同单克隆抗体的相对疗效以及先天效应器机制对阻断体内HIV进入的贡献。其次，我们将定义开发抗HIV感染人类小鼠抗体抗体的耐药性的基础。我们将使用该信息用于基于结构的理性设计方法，以迭代增强抗体的宽度和效力。该建议的这一部分的最终目标是确定哪些当前可用抗体中的哪一组对于被动疫苗和免疫原设计方法最有用。最后，我们将评估使用含有人类种系抗体前体基因的敲入小鼠中的结构和其他数据设计的潜在免疫原子。综上所述，这些实验应有助于为未来的临床研究提供信息，其中可以考虑中和抗体用于被动疗法或预防研究，其哪些目标对于免疫策略最有用。 相关性：尽管艾滋病毒仍然没有疫苗，但少数受感染的个体会产生可以预防感染的抗体。拟议的研究旨在发展对这些抗体的理解，其长期目标是能够将它们从头引起，作为将其作为疫苗的组成部分，用于未感染的个体。