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：另一种日益增长的暴露前预防方式是基于 2通过广泛中和抗艾滋病毒的被动免疫可以安全地实现预防的前提 3抗HIV包膜抗体(BNAbs)。泛中和抗体可以提供一种可行的方法来 4在全球范围内预防艾滋病毒感染。 5目标：我们的假设是，通过理性设计接近泛中和的抗CD4的bNAbs 6结合位点(CD4bs)bNAbs N49P7和N49P9.3，以罕见的HIV耐药变异体为指南，建立了一种PAN- 7可以中和临床相关的药代动力学曲线。这种泛中和抗体 8甚至包括与其他抗CD4b bNAbs(3BNC117和N6)交叉耐药的变体。我们有 9初步数据表明，N49P7和N49P9.3接近泛中和，并显示出新的结构 可用于指导改进的10个特征(例如，N49P7可访问高度保守的内部结构域 11bNAb设计。这些独特的功能为建立一个高度有效的PAN提供了尽可能接近的起点- 12中和抗体。与此同时，我们的合作者开发了设计bNAb的技术，增加了 13将PGT121的效力提高约50倍，同时保持良好的性质(溶解性和非 14自动/多反应)。该提案的具体目标是1)工程师N49P7和N49P9.3进行改进 15中和抗CD4b bNAbs的HIV-1病毒；2)从Aim 1下调选择bNAb变体 16基于体内药代动力学和生物物理性质；3)测试工程N49 bNAbs 17个人源化的小鼠模型，使用抗药性病毒来确定它们在预防HIV-1感染方面的有效性。 18种方法：我们的计划是收集更具效力和广度的N49P7和N49P9.3变体 19利用酵母表面展示，重点筛选重组识别增强的变异体 20个产生gp120s和SOSIP，来源于中和抗性病毒。带输入的组合库 21从x射线结晶学，抗体谱系分析，中和逃逸残留物和易感性分析将 22还为设计提供参考。重点将放在通过积极地降低汽车/多反应性能 23针对这些结合膜蛋白的负性选择、免疫原性预测算法和 24个种系恢复。经过3轮工程，我们将生产48株含有“LS”的人IgG1单抗。 25半衰期延长，并评价bNAbs的体外中和作用。此后，将检测8个bNAb 26自身/多反应、表达滴度、生化行为和体内半衰期。排名前两位的bNAb将是 27在人源化小鼠模型中测试针对无细胞和细胞相关艾滋病毒挑战的保护能力。 28影响：开发一种单一的、完全泛中和的抗体，具有理想的PK和溶解特性 29缺乏可辨别的多反应性将是开发免疫方法的重大进展。 30以艾滋病毒的治疗和预防为基础。