Conjugate nanoparticle platform development for HIV-1 envelope immunogens

HIV-1 包膜免疫原的共轭纳米颗粒平台开发

基本信息

批准号：
10369067
负责人：
KEVIN O SAUNDERS
金额：
$ 471.96万
依托单位：
DUKE UNIVERSITY
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：
2021-12-17 至 2026-11-30
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10369067
关键词：
2019-nCoV Affinity Amino Acids Animal Model Antibodies Antibody Affinity Antigens Avidity B-Cell Antigen Receptor B-Lymphocytes Binding Sites Biomanufacturing Cell Line Cell Lineage Chimeric Proteins Clinical Trials Complex Consumption Data Development Doctor of Philosophy Documentation Electron Microscopy Ensure Enzyme Activation Enzymes Ferritin Frequencies Future Gene Fusion Generations Goals HIV Antigens HIV Vaccine Trials Network HIV vaccine HIV-1 HIV-1 vaccine Helicobacter pylori Human Immune system Immunization Immunologics Immunology Industry Infection Influenza Hemagglutinin Investigational New Drug Application Knock-in Mouse Lead Link Macaca mulatta Molecular Conformation Mutation Nature Negative Staining Outcome Pharmaceutical Preparations Phase I Clinical Trials Process Production Reaction Regimen Series Serum Site Somatic Mutation Statistical Data Interpretation Structure Structure of germinal center of lymph node Testing Time Toxic effect United States Food and Drug Administration Vaccine Design Vaccines Viral Virion activation-induced cytidine deaminase cross reactivity design experience humanized mouse immunogenic immunogenicity improved innovation nanoparticle neutralizing antibody nonhuman primate pandemic disease phase I trial process optimization programs quality assurance sortase trafficking transpeptidation vaccination strategy vaccine evaluation vaccine platform vaccine trial

项目摘要

ABSTRACT – OVERALL HIV-1 broadly neutralizing antibodies (bnAbs) are protective in animal models of HIV-1 infection, but are not elicited in humans by current vaccine regimens. To elicit bnAbs, the B cell lineage vaccine design approach aims to administer multiple immunogens in a specific sequence to shepherd bnAb maturation through immunologic roadblocks that typically halt bnAb development. One roadblock we recently identified are somatic mutations that encode key amino acids for antibody function but that are rarely made by the somatic mutation enzyme activation-induced cytidine deaminase. Our central vaccine design hypothesis is that antibodies (Abs) encoding these improbable mutations, will be rare; thus, vaccine immunogens will need to have higher affinity for Abs with these desired amino acid changes than Abs without the amino acid changes in order to select for them. The problem facing this strategy is that the only antigen for HIV-1 bnAbs is HIV-1 envelope (Env), which is poorly immunogenic and for which bnAb precursors generally have low affinity. We and others have found these two obstacles can be overcome by designing Envs with high affinity for bnAb precursors and by multimerizing these Envs on nanoparticles (NPs) to provide avidity and improved antigen trafficking to germinal centers. However, Env trimer NPs can have low expression and present misfolded Env trimers that elicit undesired non-neutralizing Abs. This application is significant because it will establish a cGMP-compliant vaccine platform that rapidly generates higher quality HIV-1 Env trimer NP vaccines without time-consuming iterative immunogen design. This platform uses the sortase A enzyme to site-specifically, covalently-link well- folded HIV-1 Env trimers to intact Helicobacter pylori ferritin NPs. The resultant HIV-1 Env trimer sortase A- conjugated NPs (scNPs) display only well-folded Env trimers, and in preliminary studies, have successfully initiated CD4 binding site bnAb lineages in human bnAb precursor knock-in mice and CD4bs nAbs in rhesus macaques. The scNP platform is universal in nature since it can incorporate diverse viral type I fusion proteins by simply adding a 6-amino acid sortase A tag to their C-terminus. In Specific Aim 1, we will compare the ability of monovalent and bivalent HIV-1 Env scNPs to guide affinity maturation of CD4 binding site bnAbs in humanized mice and rhesus macaques. In Specific Aim 2, we will produce and assemble two CD4 binding site-bnAb- targeting HIV-1 Env trimer scNPs (CH505 TF scNP and a second sequential Env trimer scNP) under cGMP conditions. This program will deliver an optimized cGMP process for making scNPs, two cGMP-produced Env trimer scNPs, and additional ferritin and sortase A components for the manufacture of future immunogens. The CH505 TF Env trimer scNPs will be used in a Phase I trial through the HIV Vaccine Trial Network. Ultimately, the impact of this platform is that it will enable multiple Env trimer scNPs to be made rapidly under cGMP, making it feasible to do iterative testing in clinical trials of complete sequential nanoparticle vaccines that target bnAbs.

摘要 – 总体 HIV-1 广泛中和抗体 (bnAb) 在 HIV-1 感染的动物模型中具有保护作用，但并非如此通过当前的疫苗方案在人类中引发 bnAb，B 细胞谱系疫苗设计方法的目标是产生 bnAb。以特定顺序施用多种免疫原，通过免疫学促进 bnAb 成熟我们最近发现的阻碍 bnAb 发育的障碍之一是体细胞突变。编码抗体功能的关键氨基酸，但很少由体细胞突变酶产生我们的中心疫苗设计假设是抗体（Abs）。编码这些不可能的突变将是罕见的；因此，疫苗免疫原需要具有更高的亲和力具有这些所需氨基酸变化的抗体与没有氨基酸变化的抗体相比，以便选择他们面临的问题是，HIV-1 bnAb 的唯一抗原是 HIV-1 包膜（Env）。我们和其他人发现其免疫原性较差，并且 bnAb 前体通常具有较低的亲和力。这两个障碍可以通过设计对 bnAb 前体具有高亲和力的 Env 以及通过将这些 Env 多聚在纳米粒子 (NP) 上，以提供亲和力并改善抗原向生发的运输然而，Env 三聚体 NP 的表达可能较低，并且会出现错误折叠的 Env 三聚体，从而引发错误折叠。不需要的非中和抗体此应用很重要，因为它将建立符合 cGMP 的要求。无需耗时即可快速生成更高质量的 HIV-1 Env 三聚体 NP 疫苗的疫苗平台该平台使用分选酶 A 进行位点特异性共价连接。将 HIV-1 Env 三聚体折叠成完整的幽门螺杆菌铁蛋白 NP 所得的 HIV-1 Env 三聚体分选酶 A-。缀合纳米颗粒（scNP）仅显示良好折叠的环境三聚体，并且在初步研究中，已成功在人类 bnAb 前体敲入小鼠中启动 CD4 结合位点 bnAb 谱系，在恒河猴中启动 CD4bs nAb scNP 平台本质上是通用的，因为它可以整合多种病毒 I 型融合蛋白。通过简单地在其 C 末端添加 6 个氨基酸分选酶 A 标签，我们将比较其能力。单价和二价 HIV-1 Env scNP 指导人源化 CD4 结合位点 bnAb 的亲和力成熟在特定目标 2 中，我们将生产并组装两个 CD4 结合位点-bnAb-。根据 cGMP 靶向 HIV-1 Env 三聚体 scNP（CH505 TF scNP 和第二个连续 Env 三聚体 scNP）该计划将提供优化的 cGMP 工艺，用于制造 scNP（两种 cGMP 生产的环境）。三聚体 SCNP，以及用于制造未来免疫原的其他铁蛋白和分选酶 A 成分。 CH505 TF Env 三聚体 scNP 最终将通过 HIV 疫苗试验网络用于 I 期试验。该平台的影响在于，它将能够在 cGMP 下快速制备多个 Env 三聚体 SCNP，从而使在针对 bnAb 的完整序贯纳米颗粒疫苗的临床试验中进行迭代测试是可行的。