Glycan dependent epitopes of HIV broadly neutralizing antibodies

HIV广泛中和抗体的聚糖依赖性表位

• 批准号: 9291417
• 负责人: JAMES C PAULSON
• 金额: $ 96.25万
• 依托单位: SCRIPPS RESEARCH INSTITUTE, THE
• 依托单位国家: 美国
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-07-15 至 2019-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9291417
• 关键词: Acquired Immunodeficiency Syndrome; Antibodies; Antibody Response; Antibody Specificity; Antigens; Assessment tool; Binding; CD4 Positive T Lymphocytes; Cell Line; Cells; Cleaved cell; Complex; Engineering; Enzyme-Linked Immunosorbent Assay; Epitopes; Exhibits; Fab Immunoglobulins; Generations; Glycoproteins; HIV; HIV Envelope Protein gp120; HIV Envelope Protein gp41; HIV Infections; Hybrids; Immune response; Individual; Knowledge; Laboratories; Link; Mannose; Maps; Mediating; Methods; Oryctolagus cuniculus; Pathway interactions; Patients; Peripheral Blood Mononuclear Cell; Polysaccharides; Process; Proteins; Reagent; Recombinants; Regimen; Site; Specificity; Structure; Surface; Testing; Vaccine Design; Vaccines; Variant; Virus; base; cross reactivity; density; design; glycoproteomics; glycosylation; immunogenicity; interest; mutant; neutralizing antibody; novel; polypeptide; preference; prevent; public health relevance; receptor; response; scaffold

DESCRIPTION (provided by applicant): There is as yet no effective vaccine to HIV despite concerted efforts by numerous groups worldwide to produce one. The target for vaccines is the envelope spike protein (gp120/gp41), which mediates binding to receptors on the surface of CD4 T cells. The problem from a vaccine perspective is that the spike protein is heavily glycosylated, with up to 25 or more N-linked glycans, creating a 'glycan shield' that prevent an immune response to the underlying protein. Yet, many HIV infected individuals develop broadly neutralizing antibodies (bnAbs) that target the dense array of glycans. Analysis these glycan- dependent bnAbs show that they bind to different regions on the spike protein, and that they recognize different types of glycans. In particular, some antibodies exhibit high specificity for unprocessed 'high mannose' type glycans, while others exhibit specificity for more highly processed 'complex type' glycans. A major gap in current knowledge is what types of glycans are present at each glycosylation site on gp120/gp41 on the intact virus. This is critical information for understanding the optimal epitopes of glycan-dependent bnAbs. In this project we seek to better define the epitopes of glycan-dependent bnAbs, and use the information to develop immunogens that elicit a neutralizing immune response that targets the glycan shield. We will use a novel glyco-proteomics approach to analyze and determine type of glycan (high mannose or complex) for each glycosylation site on gp120/gp41 from HIV viruses produced in laboratory cell lines and peripheral blood mononuclear cells. We will use this information to produce synthetic scaffolds that carry defined glycans for characterization of the optimal epitopes of bnAbs, and to generate recombinant gp120 immunogens that approximate the glycosylation of gp120 on intact virus. Both the synthetic scaffolds and glycosylation optimized recombinant gp120 trimers will be tested for induction of neutralizing immune responses mediated by glycan-dependent gp120 antibodies.

描述（由申请人提供）：尽管全世界许多团体共同努力生产一种有效的艾滋病毒疫苗，但目前还没有有效的疫苗。疫苗的目标是包膜刺突蛋白 (gp120/gp41)，它介导与 CD4 T 细胞表面受体的结合。从疫苗的角度来看，问题在于刺突蛋白高度糖基化，具有多达 25 个或更多的 N 连接聚糖，形成了一个“聚糖盾”，可防止对基础蛋白的免疫反应。然而，许多 HIV 感染者会产生针对密集聚糖阵列的广泛中和抗体 (bnAb)。对这些聚糖依赖性 bnAb 的分析表明，它们与刺突蛋白上的不同区域结合，并且识别不同类型的聚糖。特别是，一些抗体对未加工的“高甘露糖”型聚糖表现出高度特异性，而另一些抗体则对高度加工的“复杂型”聚糖表现出特异性。目前知识的一个主要空白是完整病毒的 gp120/gp41 上的每个糖基化位点存在什么类型的聚糖。这是了解聚糖依赖性 bnAb 的最佳表位的关键信息。在这个项目中，我们寻求更好地定义聚糖依赖性 bnAb 的表位，并利用这些信息来开发免疫原，以引发针对聚糖屏蔽的中和免疫反应。我们将使用一种新颖的糖蛋白质组学方法来分析和确定实验室细胞系和外周血单核细胞中产生的 HIV 病毒的 gp120/gp41 上每个糖基化位点的聚糖类型（高甘露糖或复合物）。我们将利用这些信息来生产带有确定聚糖的合成支架，用于表征 bnAb 的最佳表位，并生成与完整病毒上 gp120 糖基化近似的重组 gp120 免疫原。将测试合成支架和糖基化优化的重组 gp120 三聚体是否诱导聚糖依赖性 gp120 抗体介导的中和免疫反应。