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

• 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
• 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

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）：开发基于抗体的疫苗针对三聚体病毒包膜尖峰蛋白对于预防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成为一项艰巨的任务。话虽如此，从人B细胞中分离出的三种最广泛的中和抗体（BNAB）（4E10，2F5，Z13E1）针对GP41的独特而且高度保守的GP41段，称为膜近代近代近形瘤区域（MPER）。虽然含有MPER刺激的强抗体反应的病毒样颗粒（VLP）-GP41构建体，但我们观察到它们的抗GP41特异性优先针对C螺旋，并远离MPER。因此，为了降低免疫原的复杂性，我们最近使用NMR和EPR方法来表征脂质体的MPER片段在脂质体，双皮细胞和胶束之前和之后，BNAB结合。这些发现表明，通过鉴定BNAB触发了由4E10和2F5诱导的病毒MPER区域的构象改变，这表明了一种新型的HIV免疫策略，并暗示了这两个BNAB在其中的色氨酸残基的扰动功能，对融合孔的活性至关重要。相比之下，Z13E1冻结了螺旋 - 铰链螺旋螺旋mper段的铰链运动。四组研究人员计划利用其集体才能在结构免疫学，疫苗学，炎症研究，生物材料和B细胞生物学中运送脂质剂量的MPER纳米颗粒来进行疫苗接种，以便产生BNABS。 Reinherza/Vagner组将分析自由和抗体结合状态下脂质环境中HIV MPER的结构，将中和与抗体触发的构象变化相关联在亚稳态铰链链接的MPER段周围。尔湾组将创建由嵌入CD4 T细胞表位的PLGA核心颗粒组成的多功能MPER纳米颗粒，并由外脂质囊泡或皮肤封装，通过针对TLRS的靶向靶向MPER向免疫系统呈现MPER。 SITKOVSKV组通过预防疫苗诱导的炎症在疫苗接种过程中扩增免疫反应，这通过A2AR/A2BR细胞外腺苷受体受体介导的免疫抑制的拮抗作用。 Kelsoe组将分析生发中心的诱导，IG类转换重组和超成名，血清抗体的亲和力成熟和生成中心B细胞对MPER免疫原子的响应。结合项目1-3，将确定和优化记忆B细胞和长期浆细胞群体的动力学。包括具有合伙计划的行政核心。