MULTI-DIMENSIONAL NMR OF HIV NEUTRALIZING ANTIBODIES

HIV 中和抗体的多维核磁共振

• 批准号: 6214357
• 负责人: JACOB ANGLISTER
• 金额: $ 12.5万
• 依托单位: WEIZMANN INSTITUTE OF SCIENCE
• 依托单位国家: 美国
• 财政年份: 1997
• 资助国家: 美国
• 起止时间: 1997-09-01 至 2003-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6214357
• 关键词: AIDS vaccines; HIV envelope protein gp120; antigen antibody reaction; antiviral antibody; genetic mapping; human immunodeficiency virus 1; neutralizing antibody; nuclear magnetic resonance spectroscopy; protein structure; vaccine development

DESCRIPTION (from applicant's abstract): The third variable loop (V3) of the envelope glycoprotein, gpl20, is a major neutralizing determinant of HIV-1. Segments of V3 form the binding site for the gpl20 co-receptors on T-cells and macrophages and its sequence determines the virus phenotype, i.e. whether it binds the CCR5 chemokine receptor and infects macrophages (M-tropic virus), or it binds CXCR4 and infects T-cells (T-tropic virus). Antibody binding to V3, or its deletion, prevent the viral fusion with the target cells, thus abolishing its infectivity. Neutralization of a variety of HIV-1 strains, including field isolates, has been shown with serum obtained after immunization with antigens containing V3 peptides of different strains. Immunization with a "cocktail" of peptides may overcome the V3 sequence variability problem. Phase I/II clinical trials of candidate vaccines containing V3 peptides have been conducted. Passive immunization with a chimeric form of the murine strain-specific anti-gpl20 antibody 0.5beta, directed against V3, was found to protect chimpanzees from HIV-1 infection. The human monoclonal antibody 447-52D was found to neutralize a broad spectrum of laboratory-adapted HIV-1 strains and both syncytium inducing (SI) and non-syncytium inducing (NSI) field isolates. The structure of V3 peptides of different HIV-1 strains, including a primary-isolate V3, bound to 447-52D will be determined using uniformly 13C, 15N and 2H labeled peptides in combination with TROSY and isotope-edited NMR experiments. The Fab-peptide interactions will be studied as well. In addition, the solution structure of the whole cyclic V3MN bound to 0.5beta and V3JR-FL bound to 447-52D will be determined. The structural differences between V3 of T-tropic and M-tropic viruses will be examined. The importance of each V3 residue for 0.5beta binding and the conformational changes in 0.5beta upon V3 binding will be studied. Our studies will provide a structural insight into the different determinants within V3: the regions involved in co-receptor binding, the residues that select the co-receptor used by the virus and the variable spots that help the virus evade the immune system. Our studies may help to determine the optimal length of peptide immunogens to be used in a peptide-based vaccine against HIV, to design constrained peptides immunogens for better cross-reactivity of anti-peptide antibodies with the virus, and to select an appropriate mixture of V3 peptides from different HIV isolates to induce a broadly neutralizing antibody response.

描述（来自申请人的摘要）： 包膜糖蛋白gp 120是HIV-1的主要中和决定簇。 V3的区段形成T细胞上gpl 20共受体的结合位点， 巨噬细胞及其序列决定了病毒的表型，即它是否 结合CCR 5趋化因子受体并感染巨噬细胞（M嗜性病毒），或 它结合CXCR 4并感染T细胞（嗜T病毒）。与V3结合的抗体，或 它的缺失，防止病毒与靶细胞融合，从而消除了 它的传染性。中和各种HIV-1毒株，包括田间 分离株，已显示与抗原免疫后获得的血清 含有不同菌株的V3肽。免疫接种与“鸡尾酒”的 肽可以克服V3序列可变性问题。I/II期临床 已经进行了含有V3肽的候选疫苗的试验。 用鼠品系特异性抗体的嵌合形式进行被动免疫 发现针对V3的抗gp 120抗体0.5 β可保护 黑猩猩免受HIV-1感染。人单克隆抗体447- 52 D是 发现可以中和广泛的实验室适应性HIV-1毒株， 合胞体诱导（SI）和非合胞体诱导（NSI）田间分离株。 不同HIV-1毒株的V3肽的结构，包括一个 结合447- 52 D的初级分离株V3将使用均匀13 C测定， 15 N和2 H标记的肽与TROSY和同位素编辑的NMR组合 实验还将研究Fab-肽相互作用。此外，本发明还提供了一种方法， 结合到0.5 β和V3 JR-FL的整个环状V3 MN的溶液结构 447- 52 D的结合将被确定。V3之间的结构差异 将检查T嗜性和M嗜性病毒。每个V3的重要性 0.5 β结合的残基和V3后0.5 β的构象变化 将研究约束力。我们的研究将提供一个结构性的见解， V3内的不同决定簇：参与共受体结合的区域， 选择病毒使用的共受体的残基和可变的 帮助病毒逃避免疫系统的斑点。我们的研究可能有助于 确定肽免疫原的最佳长度， 基于肽的抗HIV疫苗，设计限制性肽免疫原 为了使抗肽抗体与病毒具有更好的交叉反应性， 选择来自不同HIV分离株的V3肽的适当混合物， 诱导广泛中和抗体反应。