Molecular and Structural Studies of Antibody Diversity Mechanisms

抗体多样性机制的分子和结构研究

• 批准号: 9868578
• 负责人: Vaughn Vasil Smider
• 金额: $ 29.07万
• 依托单位: APPLIED BIOMEDICAL SCIENCE INSTITUTE
• 依托单位国家: 美国
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-09-30 至 2022-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9868578
• 关键词: Molecular; Structural; Studies; Antibody; Diversity

Abstract Antibodies are extremely important as the primary mediators of the immune response to infectious agents and vaccines, but also as recombinant molecules used as therapeutics, diagnostics, and research reagents. Thus, understanding the mechanisms by which antibodies form, bind, and neutralize their targets is very important in multiple biomedical areas. Most vertebrate antibody repertoires form their diversity through V(D)J recombination, where combinatorial rearrangement of V, D, and J genes form a vast repertoire where the complementarity determining regions (CDRs) form a relatively flat binding surface for interaction with antigen. Remarkably, cows appear to have a different mechanism for generating diversity and binding antigen; cow antibodies have particularly long CDR H3 regions, a subset of which can be over 70 amino acids long, which form -ribbon “stalk” and disulfide-bonded “knob” minidomains that protrude far from the typical antibody surface. Remarkably, antibodies from this repertoire can potently and broadly neutralize HIV, whereas normal human or mouse antibody repertoires cannot. Therefore, they have unique abilities to bind and neutralize particularly challenging antigens. Here we propose studies to understand in molecular detail the genetic mechanisms underlying formation of these antibodies, the binding properties of the stalk and knob minidomains, and the unique potential of these antibodes to bind bivalently and bispecifically. These studies will provide insight into mechanisms of viral neutralization generally, and particularly HIV neutralization. Additionally, given the potential of these antibodies to bind recessed epitopes, we will generate additional antibodies against particularly challenging antigens like enzymatic active sites and ion channels. We will employ mutagenesis, binding, and structural methods, as well as cellular assays to evaluate the unique properties of these antibodies. Understanding this novel class of antibodies in detail could provide fundamental insights needed for effective vaccine design as well as discovery and engineering of antibodies against some of the most challenging targets in biomedicine. Similarly, our unique antibodies discovered and characterized in this proposal could eventually become therapeutic candidates themselves.

抽象的 抗体非常重要，因为免疫响应的主要介体 传染性剂和疫苗，也是用作治疗的重组分子， 诊断和研究试剂。这是了解抗体的机制 在多个生物医学领域，形式，结合和中和目标非常重要。最多 脊椎动物抗体曲目通过V（d）J重组形成其多样性，其中 V，D和J基因的组合重排构成了一个广阔的曲目 互补性确定区域（CDR）形成相对平坦的结合表面以进行相互作用 与抗原。值得注意的是，牛似乎具有产生多样性的不同机制 和结合抗原；牛抗体具有特别长的CDR H3区域，其中一个子集 可以长70多个氨基酸，形成-丝带“茎”，并二硫键键入“旋钮” 远离典型抗体表面的小型膜。值得注意的是，抗体来自 该曲目可能会潜在地和广泛中和HIV，而正常的人或小鼠 抗体库不能。因此，它们具有绑定和中和的独特能力 特别具有挑战性的抗原。在这里，我们建议研究以分子详细了解 这些抗体的遗传机制，茎的结合特性 和旋钮的初学酶，以及这些抗体以二人结合的独特潜力和 双方。这些研究将洞悉病毒神经化的机制 通常，尤其是HIV神经化。此外，考虑到这些潜力 结合嵌入式表位的抗体，我们将特别生成针对的其他抗体 具有挑战性的抗原，例如酶活性位点和离子通道。我们将采用诱变， 结合方法和结构方法以及细胞评估，以评估 这些抗体。了解这一新颖的抗体可以详细提供 有效疫苗设计以及发现和工程所需的基本见解 针对生物医学中一些最具挑战性靶标的抗体。同样，我们的独特之处 在该提案中发现和表征的抗体最终可能成为治疗 候选人自己。