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）：尽管全球许多小组共同努力生产一种，但尚无对艾滋病毒的有效疫苗。疫苗的靶标是包膜尖峰蛋白（GP120/GP41），它介导了与CD4 T细胞表面的受体结合。从疫苗的角度来看，问题是峰值蛋白被大量糖基化，最多25或更多的N连接聚糖，从而产生“ Glycan Shield”，以防止对基础蛋白质的免疫反应。然而，许多艾滋病毒感染的个体会形成广泛中和抗体（BNAB），这些抗体（BNAB）靶向密集的聚糖阵列。分析这些依赖性的BNAB表明它们与峰值蛋白上的不同区域结合，并识别不同类型的聚糖。特别是，某些抗体对未加工的“高甘露糖”类型聚糖表现出很高的特异性，而另一些抗体则表现出特异性的特异性。当前知识的一个主要差距是在完整病毒上的GP120/GP41上的每个糖基化位点存在哪些类型的聚糖。这是理解聚糖依赖性BNAB的最佳表位的关键信息。在这个项目中，我们试图更好地定义依赖聚糖的BNAB的表位，并使用这些信息来开发免疫原子，从而引发针对聚糖屏蔽的中和免疫反应。我们将使用一种新型的Glyco-蛋白质方法方法来分析和确定从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）。我们将使用此信息产生合成支架，这些支架携带定义的聚糖来表征BNAB的最佳表位，并产生重组GP120免疫原子，以近似于完整病毒的GP120的糖基化。合成支架和糖基化优化的重组GP120三聚体都将经过测试，以诱导由聚糖依赖性GP120抗体介导的中和免疫反应。