Multifunctional Human Anti-HIV Antibodies

多功能人抗HIV抗体

• 批准号: 8427351
• 负责人: CARLOS F BARBAS
• 金额: $ 44.53万
• 依托单位: SCRIPPS RESEARCH INSTITUTE, THE
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-03-01 至 2015-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8427351
• 关键词: Acute; Address; Amino Acids; Anti-HIV Therapy; Antibodies; Binding; Binding Sites; Biological; Biological Assay; CCR5 gene; CXCR4 gene; Cell Surface Receptors; Cell surface; Chemicals; Chemistry; Chemokine (C-C Motif) Receptor 5; Coupled; Coupling; Cysteine; Engineering; Evaluation; Evolution; Fc Receptor; Fc domain; Genes; Genetic; Genetic screening method; Goals; HIV; HIV Antibodies; HIV Antigens; HIV Entry Inhibitors; HIV Envelope Protein gp120; HIV Fusion Inhibitors; HIV envelope protein; HIV-1; Half-Life; Human; Immunoglobulin G; Immunotherapeutic agent; Individual; Life; Ligation; Link; Maleimides; Modification; Mus; Mutation; Pharmaceutical Preparations; Post-Translational Protein Processing; Prophylactic treatment; Proteins; Publishing; Reaction; Receptor Cell; Research; Resistance; SCID Mice; Serum; Site; T-Lymphocyte; Testing; Therapeutic; Toxic effect; Triazoles; Tyrosine; Viral; antibody engineering; antibody-dependent cell cytotoxicity; design; human tissue; improved; in vivo; inhibitor/antagonist; neonatal Fc receptor; neutralizing antibody; novel; pressure; prevent; prophylactic; public health relevance; receptor; scaffold; single molecule; small molecule; stoichiometry; tissue culture

DESCRIPTION (provided by applicant): In this application, we are proposing to create a novel class of anti-HIV-1 immunotherapeutics by conjugating HIV-1 fusion inhibitors to exceptionally broadly neutralizing antibodies (bNABS). The cell surface receptors utilized by HIV-1 (CD4, CCR5, CXCR4) are attractive targets for therapy because they are under no pressure to evolve resistance. Unfortunately, HIV envelope protein (Env) mutations are readily evolved to escape small molecule receptor blockade. Likewise, bNABs have been discovered that neutralize up to 90% of tested viral strains but when HIV is challenged with antibodies, in vivo resistance quickly develops. In both cases, the resistance is due to mutations in the Env, although mutations to escape one molecule can make HIV more sensitive to another. Our hypothesis is that a bNAB modified with anti-HIV fusion inhibitor would be an exceptionally potent compound and that a sufficiently modified bNAB would be multifunctional and act as single molecule "cocktail." Such a compound would make evolution of resistance very difficult for HIV because it would require many mutations to escape the binding sites of the bNABs and the sterically blocked cell receptor sites. We propose to synthesize validated small molecule HIV inhibitors that target the co-receptors CCR5 and CXCR4, as well as, small molecules that bind and disrupt the CD4/gp120 fusion. These compounds will be synthesized linked to protein reactive moieties which will allow for specific modification of bNABs. Our lab has recently developed two different approaches for specific targeting of tyrosine residues for this purpose. The well characterized and very broadly neutralizing antibodies PG9 and VRCO1 will serve as the scaffold for modification. In addition to chemical modification, we will also investigate creating genetic fusions to combine the Fv's of PG9 and VRCO1 onto a single molecule, as well as, engineering the Fc domain to increase in vivo half-life. Multi-specific antibodies will be assessed for their ability to neutralize a broad panel of HIV-1 isolates including strains which are resistant to the bNABs and the small molecule fusion inhibitors. Successful candidate antibodies will then be assayed for half-life and toxicity. Finally, multi-specific antibodies will be used in an HIV escape assay to test our hypothesis that these molecules can pose an evolutionary challenge that HIV cannot answer. We anticipate that the products of this research will be exceptionally potent and broadly active HIV-1 immunotherapeutics and prophylactics.

描述（由申请人提供）：在本申请中，我们提议通过将HIV-1融合抑制剂结合到极为广泛的中和抗体（BNAB）来创建一类新型的抗HIV-1免疫治疗药。 HIV-1（CD4，CCR5，CXCR4）使用的细胞表面受体是治疗的有吸引力的靶标，因为它们没有进化抗性的压力。不幸的是，HIV包膜蛋白（ENV）突变很容易进化，以逃避小分子受体阻滞。同样，已经发现BNAB被发现中和多达90％的测试病毒菌株，但是当HIV受到抗体的挑战时，体内耐药很快就会发展出来。在这两种情况下，抗性都是由于ENV中的突变引起的，尽管逃脱一个分子的突变可以使HIV对另一种分子更敏感。我们的假设是，用抗HIV融合抑制剂修饰的BNAB将是一种非常有效的化合物，并且足够修饰的BNAB将是多功能的，并充当单分子“鸡尾酒”。这种化合物将使HIV的耐药性进化非常困难，因为它需要许多突变才能逃脱BNAB的结合位点和固有封闭的细胞受体位点。我们建议合成靶向共受体CCR5和CXCR4的小分子HIV抑制剂，以及结合和破坏CD4/GP120融合的小分子。这些化合物将与蛋白质反应性部分合成，这将允许对BNAB进行特定的修饰。为此，我们的实验室开发了两种不同的方法来针对酪氨酸残基的特定靶向。良好的特征和非常广泛的中和抗体PG9和VRCO1将作为修饰的支架。除了化学修饰外，我们还将研究创建遗传融合，以将PG9和VRCO1的FV相结合到单个分子上，以及工程FC结构域以增加体内半衰期。将评估多特异性抗体的能力，以中和一组HIV-1分离株，包括对BNABS抗性和小分子融合抑制剂的菌株。然后，将对成功的候选抗体进行半衰期和毒性进行测定。最后，将在HIV逃生测定法中使用多特异性抗体来检验我们的假设，即这些分子可以提出HIV无法回答的进化挑战。我们预计这项研究的产物将具有异常有效且广泛活跃的HIV-1免疫疗法和预防药物。