Modulating antigenic and immunogenic properties of HIV Env by altering signal sequence

通过改变信号序列调节 HIV Env 的抗原和免疫原性特性

基本信息

批准号：
10357790
负责人：
Chitra Upadhyay
金额：
$ 71.44万
依托单位：
ICAHN SCHOOL OF MEDICINE AT MOUNT SINAI
依托单位国家：
美国
项目类别：
财政年份：
2019
资助国家：
美国
起止时间：
2019-03-21 至 2024-02-29
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10357790
关键词：
Acute Affect Amino Acid Substitution Amino Acids Anabolism Antibodies Antibody Response Antigen-Presenting Cells Antigens Cell Communication Cells Competence Complex Data Development Dissociation Epitopes Fc Receptor Goals HIV HIV Envelope Protein gp120 HIV vaccine HIV-1 Helper-Inducer T-Lymphocyte Human Immune response Immunization Immunize Investigation Lectin Mannose Mass Spectrum Analysis Mediating Monoclonal Antibodies Mus Mutation Oligosaccharides Peptide Signal Sequences Peptides Phenotype Play Polysaccharides Post-Translational Protein Processing Property Proteins Recombinants Regimen Resistance Risk Role T cell response Testing Vaccines Virion Virus antibody-dependent cell cytotoxicity antibody-dependent cellular phagocytosis antigen processing base design env Gene Products experimental study glycosylation humanized mouse immunogenic immunogenicity improved interest mouse model mutant nonhuman primate novel novel strategies protective efficacy stem sugar uptake vaccine trial vaccine-induced antibodies

项目摘要

Project Summary Modest protection of RV144 trial correlated with non-neutralizing antibodies targeting the V1V2 and V3 region of HIV Env and antibody-dependent cellular cytotoxicity (ADCC) activity. These findings reinvigorated the interest in HIV vaccine approaches that can induce protective Abs, neutralizing and non-neutralizing, with Fc functional competency. This proposal will investigate the role of Env signal sequence (SS) in modulating the capacity of HIV Env to elicit protective anti-Env Abs with Fc functions. The proposed study is based on our preliminary findings that, by swapping the SS of HIV isolate AA05 with SS from another isolate AC02, we produced gp120 (AA05-02SS) that induced V1V2 and V3 Ab response with increased breadth, higher titers, and most importantly greater Fc function in immunized mice. Abs induced by gp120 AA05-02SS cross-reacted with V2 peptides of JRFL, MN, HxB2 and A244, while the WT gp120 AA05 bound weakly to V2 of HxB2 only. Notably, Abs induced by AA05-02SS displayed V1V2-specific ADCP activity while the WT gp120 AA05 did not. Indeed, SS-swap altered the proportion of high-mannose and complex glycans on the AA05- 02SS vs WT AA05 gp120 as shown by mass spectrometry; these changes were at N-glycans that are in the V1V2, C2, V3 and the V4 loop of gp120. We also found that swapping AA05 and AC02 SS onto HIV REJO Env rendered REJO virus more resistant to neutralization by V1V2-specific mAbs. SS-induced changes of Env immunogenicity and virus neutralization phenotype correlated with altered Env recognition by mAbs and lectins specific for high-mannose and complex sugars. In a separate study, single mutations introduced to the Env SS of REJO or JRFL also affected oligosaccharide compositions of N-glycans on virion-associated Env, which in turn modulated Env recognition and virus sensitivity to neutralization by V1V2- and V3-specific mAbs. Hence, we propose an overall hypothesis that, by altering the Env SS, we can regulate the glycosylation of HIV Env to impact on epitope exposure/stability and immunogenicity, and by selecting a particular SS or SS residue/s we can generate Env immunogen with enhanced capacity to elicit functional Abs. We will test this idea by assessing the SS-swapped/mutant Env immunogens for changes in epitope exposure and stability by probing with Abs and for changes in N-glycan sugars by high energy C-trap dissociation mass spectrometry (Aim 1). We will immunize mice with selected SS-modified Env immunogens and compare their capacity to induce Env-specific Abs with Fc functions. We will also identify the SS signature associated with induction of functional Abs. Immunization regimen that produced Abs with or without Fc functions will be used to isolate mAbs (Aim 2). We will evaluate the protective efficacy of vaccine-induced Abs elicited by SS- modified Env immunogens in passive transfer/HIV challenge experiments using humanized mouse model (Aim 3). Data from this study will provide vital information about HIV Env SS that can be exploited to design more effective HIV vaccine capable of eliciting protective Ab response against HIV.

项目摘要 RV144试验的适度保护与针对V1V2和V3的非中和抗体有关 HIV ENV和抗体依赖性细胞毒性（ADCC）活性的区域。这些发现重新启动对HIV疫苗方法的兴趣，可以引起保护性ABS，中和和非中和化的兴趣 FC功能能力。该建议将研究Env信号序列（SS）在调制中的作用 HIV ENV通过FC功能引起保护性抗ENV ABS的能力。拟议的研究是基于我们的初步发现，通过将HIV分离物AA05与另一个分离株AC02的SS交换，我们生产的GP120（AA05-02SS），诱导V1V2和V3 AB响应，宽度增加，更高滴度，最重要的是免疫小鼠中的FC功能更大。 GP120 AA05-02SS诱导的ABS 与JRFL，MN，HXB2和A244的V2肽交叉反应，而WT GP120 AA05弱结合至V2 仅HXB2。值得注意的是，由AA05-02S诱导的ABS显示了V1V2特异性ADCP活动，而WT GP120 AA05没有。实际上，SS-S-swap改变了AA05-上高甘露糖和复杂聚糖的比例 02SS vs WT AA05 GP120如质谱法所示；这些变化是在N-聚糖中 V1V2，C2，V3和GP120的V4环路。我们还发现将AA05和AC02 SS交换到HIV REJO ENV上 V1V2特异性mAb对中和更具抵抗力的Rejo病毒。 SS引起的ENV的变化免疫原性和病毒中和表型与mAb和凝集素的环境识别改变相关特定于高甘露糖和复杂的糖。在另一项研究中，引入ENV SS的单个突变 rejo或jrfl还影响了与病毒体相关的env上N-聚糖的寡糖组成转向V1V2和V3特异性mAb中和对中和的病毒敏感性。因此，我们提出了一个总体假设，即通过改变ENV SS，我们可以调节HIV的糖基化。 env对表位暴露/稳定性和免疫原性影响，并选择特定的SS或 SS残基，我们可以产生具有增强能力引起功能性ABS的能力的ENV免疫原。我们将通过评估表位暴露的变化和通过探测ABS的稳定性，并通过高能量C陷阱分离质量来改变N-聚糖糖的变化光谱法（AIM 1）。我们将通过选定的SS修饰的Env免疫剂对小鼠进行免疫，并比较其通过FC功能诱导ENV特异性ABS的能力。我们还将确定与诱导功能性ABS。将使用或没有FC功能的ABS产生的ABS的免疫治疗方案隔离mAb（AIM 2）。我们将评估SS-引起的疫苗诱导的ABS的保护性疗效使用人源化小鼠模型的被动转移/HIV挑战实验中的修饰ENV免疫原（AIM） 3）。这项研究的数据将提供有关HIV Env SS的重要信息，这些信息可以利用以设计更多有效的HIV疫苗能够引起针对HIV的保护性AB反应。