A new strategy to eliminate HIV-1-infected cells by unlocking the Env trimer

通过解锁Env三聚体消除HIV-1感染细胞的新策略

• 批准号: 10756846
• 负责人: Andres Finzi
• 金额: $ 71.63万
• 依托单位: HENRY M. JACKSON FDN FOR THE ADV MIL/MED
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-08-07 至 2027-07-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10756846
• 关键词: Antibodies; Antibody Therapy; Antibody-Dependent Enhancement; Antigen Receptors; Binding Sites; CD4 Antigens; CD4 Positive T Lymphocytes; Cell physiology; Cells; DNA; Data; Development; Early treatment; Engineering; Engraftment; Epitope Mapping; Epitopes; Evaluation; Family; Fc Receptor; Generations; Glycoproteins; Goals; HIV; HIV Envelope Protein gp120; HIV-1; Hybrids; Immunodominant Epitopes; In Vitro; Individual; Infection; Knowledge; Lead; Length; Link; Mediating; Mus; Natural Killer Cells; Peripheral Blood Mononuclear Cell; Persons; Plasma; Population; Research; Site; Specificity; Structure; Surface; System; Testing; Therapeutic antibodies; Transfer RNA; Variant; Viral; Viral reservoir; Virion; Virus; antibody engineering; antibody-dependent cell cytotoxicity; antiretroviral therapy; cancer therapy; design; flexibility; humanized mouse; in vivo; mimetics; neutralizing antibody; next generation; novel; particle; prevent; receptor binding; small molecule; success; synergism; tool; unnatural amino acids; viral rebound; weapons

Project Abstract The difficulty in eliminating HIV-1-infected cells is a major roadblock in eradication strategies. This is due to several factors which includes the occlusion of vulnerable HIV-1 envelope glycoprotein (Env) epitopes that can be recognized by antibodies (Abs) capable of potent Fc-effector functions such as Antibody-Dependent Cellular Cytotoxicity (ADCC). With this application we propose to engineer Abs specific for highly conserved CD4 induced (CD4i) Env epitopes to overcome these obstacles and facilitate the elimination of HIV-1 infected cells via ADCC. Accordingly, our central hypothesis is that CD4i therapeutic Abs (tAbs) will be capable of more effective elimination of infected primary CD4+ cells in the presence of HIV+ plasma than the best in class broadly neutralizing Abs (bnAbs) and can thus be developed into a new family of tAb that will be effective in decreasing and ultimately eliminating the viral reservoir in people living with HIV-1 (PLWH). The proposed research builds upon our successful development of new Ab-CD4 hybrids from weakly neutralizing or CD4i Abs specific for the coreceptor binding site (CoRBS) or highly conserved, non-neutralizing gp120 inner domain Cluster A region. Our lead CoRBS and Cluster A Ab-CD4 hybrids efficiently eliminate cells infected with primary HIV-1 isolates both in vitro and ex vivo, demonstrating that they can circumvent the occlusion of epitopes on infected cells and virions. Furthermore, they are also able to harness the ADCC activity of Abs present in HIV+ plasma, further enhancing ADCC. Finally, an anti-Cluster A Ab-CD4 hybrid (e.g., A32-CD4) also inhibited viral rebound in hu-mice and led to a significant reduction in integrated HIV DNA in an Fc-dependent manner. In the proposed project, we will engineer Ab-CD4s of other CD4i specificities and also replace the CD4 moiety with potent small molecule CD4 mimetic compounds (CD4mc). These next generation Ab-CD4mc conjugates will efficiently sensitize HIV-1 infected cells to ADCC-mediated killing, providing a new tool to decrease the HIV-1-infected cell reservoir in PLWH. Aim 1 is designed to prepare Ab-CD4 hybrids of other CD4i specificities including the Cluster A, C11- like and the gp41 Principal Immunodominant regions. Aim 2 will develop Ab-CD4mc conjugates in which the CD4 moiety of the Ab-CD4 will be replaced by a new generation of small compound CD4mcs including BNM-III- 170 and/or more active CD4mcs. The CD4mc will be attached to the Ab through a PEG linker using a novel tRNA suppressor system. Ab-CD4/CD4mcs will be evaluated in vitro and ex-vivo for their ability to neutralize primary viruses and eliminate HIV-1-infected cells alone or synergistically with HIV+ plasma, both in vitro and ex-vivo. Aim 3 will test the capacity of the best engineered variants to reduce the size of viral reservoir in humanized mice engrafted with PBMC from PLWH. This final aim will evaluate the capacity of the most promising engineered variants to eliminate infected cells in vivo and delay viral rebound. Overall, the project will generate a new family of potent tAbs able to eliminate HIV-1 infected cells to add new weapons to the growing arsenal aimed at achieving a functional cure of HIV-1.

项目摘要 消除HIV-1感染细胞的困难是根除策略的主要障碍。这是由于 几个因素包括易受攻击的HIV-1包膜糖蛋白（ENV）表位，可以 可以通过能够有效的FC效应（例如抗体依赖性细胞）的抗体（ABS）识别 细胞毒性（ADCC）。通过此应用，我们建议设计针对高度保守的CD4诱导的ABS （CD4I）ENV表现以克服这些障碍并促进通过ADCC消除HIV-1感染的细胞。 因此，我们的中心假设是CD4I治疗性ABS（TABS）将能够更有效 在HIV+等离子体存在下消除感染的原代CD4+细胞，而不是班级中最好的细胞 中和ABS（BNABS），因此可以发展为一个新的TAB家族，该家族将有效减少 并最终消除了患有HIV-1（PLWH）的人的病毒储存库。拟议的研究建造 我们成功地开发了新的AB-CD4杂种，从弱中和或CD4I ABS开发 CORECEPTOR结合位点（CORB）或高度保守的非中和化GP120内域群集A区域。我们的 Lead Corb和cluster A AB-CD4杂种有效地消除了被原发性HIV-1分离株感染的细胞， 体外和外体，表明它们可以绕过受感染细胞和病毒体上表位的阻塞。 此外，他们还能够利用HIV+等离子体中存在的ABS的ADCC活动，进一步增强 ADCC。最后，抗群集A AB-CD4混合动力车（例如A32-CD4）也抑制了HU - 小鼠的病毒反弹并LED 以FC依赖性方式显着减少综合HIV DNA。在拟议的项目中，我们将 其他CD4I特异性的工程师AB-CD4，也用有效的小分子CD4代替CD4部分 模拟化合物（CD4MC）。这些下一代AB-CD4MC结合物将有效地敏感HIV-1 感染了ADCC介导的杀戮细胞，提供了一种新工具，以减少HIV-1感染的细胞储存库 plwh。 AIM 1旨在准备其他CD4I特异性的AB-CD4杂种，包括簇A，C11- 喜欢和gp41主要免疫主导区域。 AIM 2将开发AB-CD4MC共轭物 AB-CD4的CD4部分将被新一代的小型化合物CD4MC所取代 170和/或更多活性CD4MC。 CD4MC将通过使用小说将CD4MC通过PEG接头连接到AB tRNA抑制系统。 AB-CD4/CD4MC将在体外评估和Ex-Vivo中和它们的能力 原发性病毒并单独消除HIV-1感染的细胞或与HIV+等离子体协同作用，无论是体外和 前体。 AIM 3将测试最佳工程变体的能力，以减少病毒储存的大小 来自PLWH的PBMC的人源化小鼠。这个最终目标将评估最有前途的能力 设计的变体可消除体内感染细胞并延迟病毒反弹。总体而言，该项目将产生 一个新的有效标签家族，能够消除HIV-1感染的细胞，以在不断增长的阿森纳添加新武器 旨在实现HIV-1的功能治疗。