Eliciting neutralizing antibodies and B cell responses using novel HIV Env immunogens in non-human primates

使用新型 HIV Env 免疫原在非人灵长类动物中引发中和抗体和 B 细胞反应

基本信息

批准号：
10549838
负责人：
Richard Thomas Wyatt
金额：
$ 340.27万
依托单位：
SCRIPPS RESEARCH INSTITUTE, THE
依托单位国家：
美国
项目类别：
财政年份：
2021
资助国家：
美国
起止时间：
2021-02-04 至 2026-01-31
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10549838
关键词：
Adolescent Adult Affinity Alleles Animals Antibodies Antibody Formation Antigens B cell repertoire B-Cell Activation B-Lymphocytes Binding Binding Sites Cavia Cell Separation Cell surface Clonal Expansion Cloning Collaborations Complement Complex Coupled Cryoelectron Microscopy Crystallography Encapsulated Epitope Mapping Epitopes Evaluation Evolution Frequencies Goals HIV HIV Envelope Protein gp120 HIV-1 vaccine Human Immune Immune response Immunity Immunization Immunodominant Epitopes Immunoglobulin G In Vitro Infection Link Lipids Liposomes Macaca Masks Membrane Memory B-Lymphocyte Messenger RNA Methods Modification Molecular Sieve Chromatography Monoclonal Antibodies Negative Staining Oryctolagus cuniculus Outcome Particulate Penetration Peptides Polysaccharides Process Property Public Health Publications Resolution Serum Site Specific qualifier value Specificity Structure Tail Technology Time Tissues Translating Vaccination Viral biophysical techniques density design experimental study follow-up glycosylation improved in vivo lipid nanoparticle lymph nodes mRNA Expression neutralizing antibody neutralizing monoclonal antibodies neutralizing vaccine nonhuman primate novel particle response screening success vaccine candidate vaccine development ward working group

项目摘要

Neutralizing antibodies are likely to be required for an effective HIV-1 vaccine. However, few candidate vaccines efficiently elicit broadly neutralizing antibodies (bNAbs) following vaccination. Recently, the VRC working group has elicited fusion peptide-directed bNAbs in guinea pigs and non-human primates (NHPs). Similarly, we recently elicited bNAbs in rabbits following heterologous NFL (uncleaved) trimer-liposome prime:boosting at Scripps where we activated B cell responses with targeted N-glycan deletions in the priming immunizations (Dubrovskaya et al, Immunity 2019). We isolated two rabbit bNAbs that recapitulate the serum activity. These bNAbs are directed against two distinct sites of Env vulnerability. The elicitation of neutralizing responses was enhanced by targeted N-glycan deletion, high-density liposomal array and heterologous trimer restorative boosting Env. In independent experiments in guinea pigs, we have elicited bNAbs in multiple animals also using a N-glycan deletion, heterologous Env NFL prime:boost approach. These recent outcomes are encouraging inroads toward the successful solution of a 3-decade-long problem. The new era of near-native trimeric spike mimics, coupled with particulate array, structure-informed design and high-resolution analysis of Env-specific B cell and lymph node responses, afford new opportunities to more efficiently elicit bNAbs. We propose an integrated, multi-faceted approach blending the expertise of world leaders in HIV Env trimer design, analysis of B cell responses and Abs following vaccination, NHP immune tissue analysis and EM-based analysis of ongoing immune responses and high-resolution Ab:trimer interactions. We will use well-ordered trimer prime:boosting that elicited bNAbs in rabbits and guinea pigs to elicit such responses in NHPs, translating success in small animals to NHPs using novel immunogen design and presentation in Project 1 (Wyatt) and immunization of NFL trimers into NHPs via Core B (Silvestri). We will use “real-time” serum Fab-to-trimer binding evaluated by EM polyclonal IgG epitope mapping (EMPEM) in Core C (Ward) in complement with rapid mAb NGS-based mAb cloning, sequencing and functional expression in Project 2 (Karlsson Hedestam). In collaboration with the VRC (Mascola) we will define either non-neutralizing mAbs to mask unwanted non-neutralizing epitopes or to better display the epitopes of cross-neutralizing mAbs. We will compare NFL trimer-liposomes to cell surface NFL trimer array expressed from the exciting mRNA lipid encapsulation technology. We will assess if immunization in the juvenile NHP B cell repertoire compared to adult macaques will better generate bNAbs as is observed during human infection. To follow our discovery of a tier 2 CD4bs-directed bNAb following trimer-liposome vaccination, termed E70, we will target the CD4bs by directed NFL trimer deglycosylation in the NHPs. Based on our recent discovery of the very broadly neutralizing vaccine-induced mAb, 1C2, we will also focus on the gp41:120 trimer interface. Leveraging these initial leads, we will undertake a multifaceted, cross-component integrated approach to guide the elicitation of bNAbs in NHPs following vaccination with near-native, uncleaved NFL Env trimers.

有效的 HIV-1 疫苗可能需要中和抗体，但候选疫苗很少。最近，VRC 工作组在疫苗接种后有效地引发了广泛中和抗体（bNAb）。同样，我们最近在豚鼠和非人灵长类动物（NHP）中引发了融合肽导向的 bNAb。在斯克里普斯的异源 NFL（未切割）三聚体脂质体引发后，在兔子中引发了 bNAbs：增强我们在初次免疫中通过靶向 N-聚糖缺失激活 B 细胞反应（Dubrovskaya 等人，Immunity 2019）我们分离了两种可概括血清活性的兔 bNAb。 bNAb 针对两个不同的 Env 脆弱性位点，引发中和反应。通过靶向 N-聚糖删除、高密度脂质体阵列和异源三聚体修复增强在豚鼠的独立实验中，我们也在多种动物中使用了 bNAb。 N-聚糖缺失、异源 Env NFL prime:boost 方法这些最近的结果令人鼓舞。成功解决了长达三十年的问题近天然三聚体尖峰的新时代。模拟，结合颗粒阵列、结构知情设计和环境特异性 B 的高分辨率分析细胞和淋巴结反应，为更有效地引发 bNAb 提供了新的机会。综合的、多方面的方法融合了世界领先者在 HIV 包膜三聚体设计、分析方面的专业知识疫苗接种后的 B 细胞反应和抗体、NHP 免疫组织分析和正在进行的基于 EM 的分析免疫反应和高分辨率 Ab:三聚体相互作用我们将使用有序的三聚体 prime:boosting。在兔子和豚鼠中引发 bNAb，在 NHP 中引发此类反应，将成功转化为小型研究项目 1 (Wyatt) 中使用新颖的免疫原设计和演示以及 NFL 的免疫接种将动物转化为 NHP 通过 Core B (Silvestri) 将三聚体转化为 NHP 我们将使用通过 EM 评估的“实时”血清 Fab-三聚体结合。 Core C (Ward) 中的多克隆 IgG 表位作图 (EMPEM) 与基于 NGS 的快速单克隆抗体互补项目 2 (Karlsson Hedestam) 与 VRC 合作进行克隆、测序和功能表达。（Mascola）我们将定义非中和性单克隆抗体来掩盖不需要的非中和性表位或更好地显示交叉中和单克隆抗体的表位我们将比较 NFL 三聚体脂质体与细胞表面 NFL 三聚体。我们将评估通过令人兴奋的 mRNA 脂质封装技术表达的阵列。与成年猕猴相比，幼年 NHP B 细胞库能更好地产生 bNAb，正如在为了追踪我们在三聚体脂质体疫苗接种后发现的 2 级 CD4bs 导向的 bNAb，根据我们最近的研究，我们将通过 NHP 中的定向 NFL 三聚体去糖基化来靶向 CD4b，称为 E70。发现了非常广泛中和的疫苗诱导单克隆抗体 1C2，我们还将关注 gp41:120 三聚体利用这些初步线索，我们将采取多方面、跨组件的集成方法。指导在接种近天然、未切割的 NFL Env 三聚体后 NHP 中 bNAb 的引发。