Engineering of pan-neutralizing anti-HIV envelope antibodies

全中和抗 HIV 包膜抗体的工程

• 批准号: 10064993
• 负责人: Mohammad Mohseni Sajadi
• 金额: $ 60.34万
• 依托单位: UNIVERSITY OF MARYLAND BALTIMORE
• 依托单位国家: 美国
• 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/10064993
• 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

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/理由：一种替代的暴露前预防态度的兴趣的模式是基于 2预防可以通过被动免疫抑制安全地实现预防的前提 3种针对HIV包膜的抗体（BNAB）。泛中和抗体可以提供可行的手段 4防止全球艾滋病毒感染。 5目的：我们的假设是，通过合理的工程，将近和bnabs与CD4进行了合理化 6使用HIV的稀有电阻变体作为指南，6个结合位点（CD4BS）bnabs n49p7和n49p9.3 7可以用临床相关的药代动力学特征进行中和。这样的泛中和抗体 8甚至将覆盖与其他抗CD4BS BNAB（3bnc117和n6）交叉抗性的变体。我们有 9初步数据表明N49P7和N49P9.3几乎是泛中和和暴露的新型结构 10个功能（例如，N49P7可以访问高度组成的内部域），可用于指导改进 11 BNAB设计。这些独特的功能为建立高潜在的泛板提供了最接近的起点 12中和抗体。同时，我们的合作者已经开发了工程bnabs的技术，增加了 13 PGT121的效力约50倍，同时保持有利的品质（溶解度和非 - 14自动/多反应性）。该提案的具体目的是1）工程师N49P7和N49P9.3改进 15 HIV-1病毒对CD4BS BNAB的抗性谈判； 2）AIM 1的BNAB变体的降低选择 16基于体内药代动力学和生物物理特性； 3）测试工程的N49 bnabs两个 17种使用抗性病毒的人源化小鼠模型来确定其预防HIV-1感染的效率。 18种方法：我们的计划是制作N49P7和N49P9.3的集合，具有更大的效力和广度 19使用酵母表面展示，专注于选择重组识别的变体 20种产生的GP120和SOSIP来自中和抗性病毒。与输入的组合库 21从X射线晶体学，抗体谱系分析，神经化逃生和责任分析中将 22也告知设计。重点将通过积极地降低自动/多反应性能 23对那些结合膜蛋白，免疫原性预测算法和 24种系反面。经过3轮工程后，我们将产生48个mAb作为人类IgG1，其中包含“ LS” 25半衰期延伸并评估BNAB的体外神经化。此后，将测试8个BNAB 26自动/多反应性，表达滴度，生化行为和体内半衰期。前两个BNAB将是 27在人性化小鼠模型中测试，以防止无细胞和与细胞相关的HIV挑战。 28影响：具有理想的PK和溶解性的单个完全泛中和抗体的开发 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。