Immunogen Design for Induction of HIV distal gp41 broadly neutralizing antibodies

总体目标是开发免疫原，以启动和选择HIV-1广泛的中和抗体 (BNab)定向到HIV env gp41远端膜近端外区(MPER)的谱系。远端 Gp41MPER抗体类型，如10E8和DH511是理想的，因为它们是最广泛的 以及分离到的有效的bNAbs。对于bNab免疫原设计谱系有两种策略。(1)定义bNab 克隆性谱系，推断bNab未突变共同祖先(UCA)并选择自体 ENVS结合称为B细胞系免疫原设计。(2)基于结构的设计，使用以下结构 序列谱系抗体，用于设计绑定到bNab谱系成员的环境。在这里，我们建议将 这两种策略在设计可引发和诱导远端MPER的免疫原方面的优势 BNAbs。我们将使用新分离的DH511谱系UCA、中间抗体(IAS)和bNAbs作为 在此基础上设计顺序免疫原的试剂，该试剂将选择DH511类前体并导致 B Nab开发(项目1，William Shead，Pi)，并测试这些免疫原在生理上相关的 BNab开发的敲入小鼠模型(项目2(Munir Alam，Pi，Small Animal Models Core， 田明，派，弗雷德·阿尔特，Co-I)。用于检测的计算机程序--抗原受体突变分析仪 允许定义关键抗体的低可能性发生(螳螂)(项目2) 要诱导的体细胞突变将被用来确定成功的疫苗所需的关键免疫反应 目标。 总体特定目标1.确定一个成功的疫苗将会发生的关键免疫抑制和抗体体细胞突变 需要选择引导至远端MPER的bNab诱导。(项目1和2) 总体特定目标2.设计生殖系靶向(GT)启动和增强免疫原，以结合 DH511前体和关键的IAS和成熟的DH511 bNAbs具有最佳的亲和力，并可以选择 正确/所需的IAS和bNAb。(项目1) 总体目标3.解决DH511和类DH511谱系的共晶和低温EM结构 带有Env免疫原的抗体沿着bNab成熟途径移动谱系并使 设计额外的免疫原以完成远端MPER bNAbs B细胞系的诱导。(项目1) 总的特异性目标4.从DH511 UCA和IA的免疫中筛选出最佳的Env免疫原 VH和VL敲入小鼠。这将通过使用新颖的DH511 UCA VHDJH-重排来实现 鼠标最近由哈佛大学的田明和弗雷德·阿尔特开发。(小动物核心；项目1和2)。 三个领先的学术团队在艾滋病毒疫苗免疫原设计方面的合作将带来 结合了基于结构和基于谱系的设计方面的专业知识，将是实现 疫苗诱导一般不受欢迎的抗体谱系，特别是远端MPER bNAbs的问题。

The overall objective is to develop immunogens that will initiate and select HIV-1 broad neutralizing antibody (bnAb) lineages directed to the distal membrane proximal external region (MPER) of HIV Env gp41. Distal gp41 MPER antibody types such as 10E8 and DH511 are desirable because they are among the most broad and potent bnAbs isolated. There are two strategies for bnAb immunogen design lineages. (1) Define bnAb clonal lineage genealogies, infer the bnAb unmutated common ancestor (UCA) and select autologous Envs that bind—termed B cell lineage immunogen design. (2) Structural-based design, using structures of sequential lineage Abs to design Envs that bind to bnAb lineage members. Here we propose to combine the strengths of both strategies to design immunogens that can initiate and induce distal MPER bnAbs. We will use the newly isolated DH511 lineage UCA, intermediate antibodies (IAs) and bnAbs as reagents upon which to design sequential immunogens that will select DH511-like precursors and lead to bnab development (Project 1, William Schief, PI), and to test these immunogens in physiologically relevant knock-in mouse model of bnAb development (Project 2 (Munir Alam, PI, Small Animal Models Core, Ming Tian, PI, Fred Alt, Co-I). A computational program, Antigen Receptor Mutation Analyzer for Detection of Low Likelihood Occurrences (ARMADiLLO) (Project 2) that allows for definition of the critical antibody somatic mutations to be induced will be used to determine key IAs that a successful vaccine will need to target. Overall Specific Aim 1. Define the key IAs and antibody somatic mutations that a successful vaccine will need to select to lead to distal MPER bnAb induction. (Projects 1 and 2) Overall Specific Aim 2. Design of germline targeting (GT) prime and boost immunogens that bind to the DH511 precursors and to key IAs and mature DH511 bnAbs in optimal affinities and can select the correct/desired IAs and bnAbs. (Project 1) Overall Specific Aim 3. Solve co-crystal and cryoEM structures of DH511 and DH511-like lineage antibodies with Env immunogens that move the lineage along the bnAb maturation pathway and enable design of additional immunogens to complete the induction of distal MPER bnAbs B cell lineages. (Project 1) Overall Specific Aim 4. Selection of optimal Env immunogens from immunizations of DH511 UCA and IA VH and VL knock-in mice. This will be accomplished by use of the novel DH511 UCA VHDJH-rearranging mouse recently developed by Ming Tian and Fred Alt at Harvard. (Small Animal Core; Projects 1 and 2). This collaboration of three leading academic teams in HIV vaccine immunogen design will bring together expertise in structure-based and lineage-based design, and will be a powerful approach to the problem of vaccine induction of disfavored antibody lineages in general and distal MPER bnAbs in particular.