Engineering of pan-neutralizing anti-HIV envelope antibodies

全中和抗 HIV 包膜抗体的工程

基本信息

批准号：
9927080
负责人：
Mohammad Mohseni Sajadi
金额：
$ 61.09万
依托单位：
UNIVERSITY OF MARYLAND BALTIMORE
依托单位国家：
美国
项目类别：
财政年份：
2019
资助国家：
美国
起止时间：
2019-12-05 至 2024-11-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/9927080
关键词：
AIDS prevention AIDS/HIV problem Adherence Animal Model Anti-Retroviral Agents Antibodies Antibody Binding Sites Antiviral Agents Autologous Behavior Binding Binding Sites Biochemical Cells Collection Crystallography Data Development Drug Combinations Drug Kinetics Engineering Ensure Exhibits Face Family Goals HIV HIV Envelope Protein gp120 HIV Infections HIV-1 Half-Life Human IgG1 Immune In Vitro Infection Libraries Life Extension Logistics Mediating Membrane Proteins Methods Modality Molecular Sieve Chromatography Monoclonal Antibodies Mutagenesis Neutralization Tests Passive Immunization Passive Immunotherapy Persons Pharmaceutical Preparations Plasma Polysaccharides Prevention Preventive Property Recombinants Resistance Risk Solubility Structure Surface Target Populations Techniques Testing Time Vaccines Variant Virus Work X-Ray Crystallography Yeasts antibody engineering base biophysical properties clinically relevant combinatorial design experimental study human monoclonal antibodies humanized mouse immunogenic immunotherapy trials improved in vivo interest mouse model neutralizing antibody novel pre-exposure prophylaxis prediction algorithm prevent prophylactic protective efficacy recruit side effect

项目摘要

1 Background/Rationale: An alternative pre-exposure prophylaxis modality of growing interest is based on the 2 premise that prevention can be safely achieved by passive immunization with broadly neutralizing anti-HIV 3 antibodies (bNAbs) against the HIV envelope. A pan-neutralizing antibody could provide a feasible means to 4 prevent HIV infection worldwide. 5 Objectives: Our hypothesis is that by rational engineering of near pan-neutralizing bNAbs against the CD4 6 binding site (CD4bs) bNAbs N49P7 and N49P9.3, using rare resistance variants of HIV as guides, a pan- 7 neutralizing with clinically relevant pharmacokinetic profiles can be made. Such a pan-neutralizing antibody 8 would even cover variants that are cross-resistant to other anti-CD4bs bNAbs (3BNC117 and N6). We have 9 preliminary data demonstrating that N49P7 and N49P9.3 are near pan-neutralizing and exhibit novel structural 10 features (e.g., N49P7 has access to the highly conserved inner domain) that can be used to guide improved 11 bNAb design. These unique features provide the closest possible starting point for building a highly potent pan- 12 neutralizing antibody. In parallel, our collaborators have developed techniques to engineer bNAbs, increasing 13 the potency of PGT121 approximately 50 times, while retaining favorable qualities (solubility and non- 14 auto/polyreactivity). The specific aims of this proposal are 1) Engineer N49P7 and N49P9.3 to improve 15 neutralization of HIV-1 viruses resistant to CD4bs bNAbs; 2) Downselection of bNAb variants from Aim 1 16 based on in vivo pharmacokinetics and biophysical properties; 3) Test engineered N49 bNAbs in two 17 humanized mouse models using resistant viruses to determine their efficacy in preventing HIV-1 infection. 18 Methods: Our plan is to make a collection of N49P7 and N49P9.3 variants with greater potency and breadth 19 using yeast surface display, focusing on selecting variants with enhanced recognition of recombinantly 20 produced gp120s and SOSIPs derived from neutralization resistant viruses. Combinatorial libraries with input 21 from x-ray crystallography, antibody lineage analysis, neutralization escape residues, and liability analysis will 22 also inform design. Emphasis will be placed on reduction of auto/polyreactive properties by aggressively 23 negatively selecting against those binding membrane proteins, immunogenic prediction algorithms, and 24 germline reversion. After 3 rounds of engineering, we will produce 48 mAbs as human IgG1 containing the “LS” 25 half-life extension and evaluate the bNAbs for in vitro neutralization. Thereafter, 8 bNAbs will be tested for 26 auto/polyreactivity, expression titer, biochemical behavior, and in vivo half-life. The top two bNAbs will be 27 tested in humanized mouse models for ability to protection against cell-free and cell-associated HIV challenge. 28 Impact: The development of a single, fully pan-neutralizing antibody with desirable PK and solubility properties 29 absent discernable polyreactivity would be a major advance in efforts to develop approaches for immune- 30 based treatment and prevention of HIV.

1 背景/基本原理：人们越来越感兴趣的另一种暴露前预防方式是基于 2 前提是通过广泛中和抗 HIV 的被动免疫可以安全地实现预防 3 针对 HIV 包膜的抗体 (bNAb) 可以提供一种可行的方法。 4 在全球范围内预防艾滋病毒感染。 5 个目标：我们的假设是，通过合理设计抗 CD4 的近泛中和 bNAb 6 结合位点 (CD4bs) bNAbs N49P7 和 N49P9.3，使用 HIV 的罕见耐药变体作为指导，是一种泛可以制备具有临床相关药代动力学特征的7中和性抗体。 8 甚至涵盖与其他抗 CD4b bNAb（3BNC117 和 N6）交叉耐药的变体。 9 初步数据表明 N49P7 和 N49P9.3 接近泛中和并表现出新颖的结构 10 个特征（例如，N49P7 可以访问高度保守的内部结构域），可用于指导改进 11 bNAb 设计这些独特的功能为构建高效的泛抗体提供了最接近的起点。与此同时，我们的合作者开发了 bNAb 工程技术，增加了 12 中和抗体。 13 PGT121 的效力约为 50 倍，同时保留良好的品质（溶解度和非降解性） 14 自动/多反应性）该提案的具体目标是 1) 改进 N49P7 和 N49P9.3。 15 中和对 CD4bs bNAb 具有抗性的 HIV-1 病毒；2) 目标 1 中 bNAb 变体的下调选择 16 基于体内药代动力学和生物物理特性 3) 在两种中测试工程化 N49 bNAb； 17 个人源化小鼠模型使用耐药病毒来确定其预防 HIV-1 感染的功效。 18 种方法：我们的计划是收集具有更大效力和广度的 N49P7 和 N49P9.3 变体 19 使用酵母表面展示，重点选择具有增强重组识别能力的变体 20 产生了来自具有输入的中和抗性病毒的 gp120 和 SOSIP。 21 来自 X 射线晶体学、抗体谱系分析、中和逃逸残留物和责任分析将 22 还强调通过积极减少自体/多反应特性。 23 对那些结合膜蛋白、免疫原性预测算法和 24种系逆转经过3轮工程，我们将生产48种含有“LS”的mAb作为人IgG1。 25 半衰期延长并评估 bNAb 的体外中和作用此后，将测试 8 种 bNAb。 26 自身/多反应性、表达滴度、生化行为和体内半衰期将是前两个 bNAb。 27 在人源化小鼠模型中测试了抵御无细胞和细胞相关 HIV 攻击的能力。 28 影响：开发具有理想 PK 和溶解度特性的单一、完全泛中和抗体 29 缺乏可辨别的多反应性将是开发免疫方法的重大进步 30 基于艾滋病毒的治疗和预防。