Eliciting B cells to produce anti-HIV gp41 MPER-specific neutralizing antibodies

诱导 B 细胞产生抗 HIV gp41 MPER 特异性中和抗体

基本信息

批准号：
8516448
负责人：
ELLIS L REINHERZ
金额：
$ 149.53万
依托单位：
DANA-FARBER CANCER INST
依托单位国家：
美国
项目类别：
财政年份：
2010
资助国家：
美国
起止时间：
2010-09-01 至 2015-08-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8516448
关键词：
Acquired Immunodeficiency Syndrome Affinity Africa South of the Sahara Amino Acid Sequence Animals Antibodies Antibody Formation Antigens Asia B-Lymphocytes Beryllium Binding Binding Sites Biology Biomaterials Research CD4 Positive T Lymphocytes Caribbean region Cell membrane Cell surface Cellular biology Central America Cessation of life Cleaved cell DNA Sequence Rearrangement Development Disease Reservoirs Down-Regulation Encapsulated Environment Enzymes Epidemic Epitopes Freezing Genome HIV HIV Envelope Protein gp41 HIV immunization HIV-1 Health Human Human Development Immune response Immune system Immunoglobulin Class Switching Immunoglobulin Switch Recombination Immunology Immunosuppression Infection Inflammation Instruction Kinetics Leucine Zippers Life Life Expectancy Ligation Link Lipids Liposomes Mediating Membrane Memory B-Lymphocyte Methods Micelles Motion Nucleosome Core Particle Plasma Cells Population Prevention Preventive Proteins Purinergic P1 Receptors Research Personnel Retroviridae Scaffolding Protein Serum Site Skin South America Specificity Structure Structure of germinal center of lymph node Surface T-Lymphocyte T-Lymphocyte Epitopes Talents Thermodynamics Tryptophan Vaccination Vaccine Design Vaccines Vesicle Viral Virion Virus base burden of illness conformational alteration extracellular global health glycosylation gp160 nanoparticle neutralizing antibody novel pandemic disease particle prevent receptor response trend vaccine development vaccinology

项目摘要

DESCRIPTION (provided by applicant): Development of antibody-based vaccines against the trimeric viral envelope spike protein is critical for prevention of HIV-1 infection. Viral sequence diversity, conformational variability and extensive envelope glycosylation have made this a challenging task. With that said, three of the most broadly neutralizing antibodies (BNABs) isolated from human B cells (4E10, 2F5, Z13e1) are directed at the uniquely accessible yet highly conserved segment of gp41 known as the membrane proximal ectodomain region (MPER). While viral-like particles (VLP)-gp41 constructs containing the MPER stimulated strong antibody responses, we observed that their anti-gp41 specificity was preferentially directed at the C-helix and away from the MPER. Consequently, to reduce immunogen complexity, we have recently used NMR and EPR methods to characterize lipid-embedded MPER segments on liposomes, bicelles and micelles prior to and after, BNAB binding. These findings suggest a novel HIV immunization strategy by identifying BNAB triggered conformational alterations in the viral MPER region induced by 4E10 and 2F5 and suggest how these two BNABs perturb function of tryptophan residues therein, critical for fusion pore activity. By contrast, Z13e1 freezes the hinge motion of the helix-hinge-helix MPER segment. Four groups of investigators plan to utilize their collective talents in structural immunology, vaccinology, inflammation research, biomaterials and B cell biology to deliver lipid-embedded MPER nanoparticles for vaccination of animals in order to generate BNABs. The ReinherzA/Vagner groups will analyze structures of HIV MPERs in lipid environments in free- and antibody-bound states, correlating neutralization with antibody-triggered conformational changes around the metastable hinge-linked MPER segment. The Irvine group will create multi-functional MPER nanoparticles consisting of PLGA core particles embedding CD4 T cell epitopes and encapsulated by an outer lipid vesicle or skin for MPER presentation to the immune system via directed targeting to TLRs. The Sitkovskv group will amplify immune responses during vaccination through prevention of downregulation of vaccine-induced inflammation via antagonism of A2AR/A2BR extracellular adenosine receptor-mediated immunosuppression. The Kelsoe group will analyze induction of germinal centers, Ig class switch recombination and hypermutation, affinity maturation of serum antibodies and germinal center B cells in response to MPER immunogens. In conjunction with Projects 1- 3, kinetics of memory B cell and long-lived plasma cell populations will be ascertained and optimized. An Administrative Core with a Partnership Plan is included.

描述（由申请人提供）：开发针对三聚体病毒包膜刺突蛋白的抗体疫苗对于预防 HIV-1 感染至关重要。病毒序列多样性、构象变异性和广泛的包膜糖基化使这一任务成为一项具有挑战性的任务。尽管如此，从人 B 细胞（4E10、2F5、Z13e1）中分离出的三种最广泛的中和抗体 (BNAB) 均针对 gp41 中独特且高度保守的片段，即膜近端胞外域区域 (MPER)。虽然含有 MPER 的病毒样颗粒 (VLP)-gp41 构建体刺激了强烈的抗体反应，但我们观察到它们的抗 gp41 特异性优先针对 C 螺旋，远离 MPER。因此，为了降低免疫原的复杂性，我们最近使用 NMR 和 EPR 方法来表征 BNAB 结合之前和之后的脂质体、bicelles 和胶束上的脂质嵌入 MPER 片段。这些发现提出了一种新的 HIV 免疫策略，通过识别 BNAB 触发由 4E10 和 2F5 诱导的病毒 MPER 区域的构象改变，并表明这两种 BNAB 如何扰乱其中色氨酸残基的功能，这对融合孔活性至关重要。相比之下，Z13e1 冻结了螺旋-铰链-螺旋 MPER 片段的铰链运动。四组研究人员计划利用他们在结构免疫学、疫苗学、炎症研究、生物材料和 B 细胞生物学方面的集体才能，提供脂质嵌入的 MPER 纳米颗粒，用于动物疫苗接种，从而产生 BNAB。 ReinherzA/Vagner 小组将分析脂质环境中 HIV MPER 在游离和抗体结合状态下的结构，将中和与抗体触发的亚稳态铰链连接 MPER 片段周围的构象变化联系起来。欧文小组将创建多功能 MPER 纳米颗粒，该纳米颗粒由嵌入 CD4 T 细胞表位的 PLGA 核心颗粒组成，并被外部脂质囊泡或皮肤封装，以便通过定向靶向 TLR 将 MPER 呈递给免疫系统。 Sitkovskv 小组将通过拮抗 A2AR/A2BR 细胞外腺苷受体介导的免疫抑制来预防疫苗诱导的炎症下调，从而放大疫苗接种期间的免疫反应。 Kelsoe 小组将分析生发中心的诱导、Ig 类别转换重组和超突变、血清抗体和生发中心 B 细胞对 MPER 免疫原的反应的亲和力成熟。结合项目 1-3，将确定和优化记忆 B 细胞和长寿命浆细胞群的动力学。其中包括带有合作伙伴计划的管理核心。