Project 1: Immunologic and Virologic Characterization of RhCMV/SIV Vaccine-Mediated SIV Replication Arrest Efficacy

项目 1：RhCMV/SIV 疫苗介导的 SIV 复制抑制功效的免疫学和病毒学特征

• 批准号: 10619302
• 负责人: Jonah B. Sacha
• 金额: $ 53.62万
• 依托单位: OREGON HEALTH & SCIENCE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-09-22 至 2027-06-30
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10619302
• 关键词: Address; Antigen-Presenting Cells; Antigens; Autologous; Autopsy; B-Lymphocytes; Biopsy; Blood Cells; CD4 Positive T Lymphocytes; CD8-Positive T-Lymphocytes; CD8B1 gene; Cells; Cellular Indexing of Transcriptomes and Epitopes by Sequencing; Characteristics; Clinic; Cytomegalovirus; DNA; Data; Disease remission; Equilibrium; Extinction (Psychology); Gene Expression; Gene Expression Profile; Genetic Transcription; Goals; HIV; HIV vaccine; Immune; Immune response; Immunity; Immunologics; Infection; Interleukin-15; Link; Macaca mulatta; Major Histocompatibility Complex; Mediating; Mononuclear; Myelogenous; Natural Killer Cells; Nature; Outcome; Output; Pattern; Peptides; Phase; Plasma; Population; Primary Infection; Process; Production; RNA; Residual state; Resistance; Resolution; Rest; Rhesus; SIV; SIV Vaccines; Signal Transduction; Site; T cell receptor repertoire sequencing; T cell response; T memory cell; T-Cell Depletion; T-Cell Receptor; Time; Tissues; Translations; Vaccinated; Vaccination; Vaccines; Viral; Viremia; Virion; Virus; Virus Diseases; Virus Replication; Whole Blood; antiretroviral therapy; base; cell type; clinical translation; cohort; efficacy evaluation; high dimensionality; immunoregulation; in vivo; indexing; pre-clinical; prevent; prophylactic; response; transcriptome sequencing; transcriptomics; vector; vector-induced

PROJECT 1 - PROJECT SUMMARY A pre-clinical HIV vaccine approach based on strain 68-1 of rhesus cytomegalovirus expressing SIV antigens (RhCMV/SIV) elicits cellular immune responses that stringently arrest replication and spread of primary SIV infection in 59% of vaccinated rhesus macaques (RMs). The vast majority of these vaccine-protected RMs will maintain this SIV replication arrest (a state of aviremia with replication-competent SIV in tissues) until virus decays or is cleared to extinction over the subsequent 1-3 years. This pattern of immune-mediated viral suppression has no prior precedent and although the precise virologic and immunological mechanisms underpinning this phenomenon remain unknown, we have established that (a) replication arrest efficacy depends on RhCMV/SIV elicitation of SIV-specific CD8+ T cells that target SIV peptides in the context of major histocompatibility complex (MHC)-E rather than MHC-II or conventional MHC-Ia, and (b) that among RMs with MHC-E-restricted CD8+ T cell responses, efficacy is predicted by a sustained whole blood transcriptomic signature featuring IL-15 signaling. These data suggest that an innate immune/IL-15 signaling-facilitated, MHC- E-restricted, SIV-specific CD8+ T cell response mediates/coordinate replication arrest efficacy and that the in vivo functional outputs underlying this pattern efficacy are unique to this response and thus different from functional outputs of other types of SIV-specific CD8+ T cell responses. This, in turn, suggests that detailed functional comparison of the effective responses with other vaccine-elicited CD8+ T cell response types that fail to mediate replication arrest efficacy (including MHC-Ia- and MHC-II-restricted responses by programmed RhCMV/SIV and MHC-Ia-restricted responses by conventional prime-boost vaccination) will elucidate differences that underlie the replication arrest outcome. Thus, in S.A.1 we will utilize T cell receptor (TCR)- indexed single cell transcriptomics to identify cell-intrinsic transcriptional patterns that distinguish these SIV- specific CD8+ T cell responses in late vaccine phase and, importantly. correlate with subsequent SIV challenge outcome (replication arrest vs. progressive infection). In S.A.2, we will virologically characterize early replication arrest, determining the tissue extent, cellular distribution and state of residual SIV (transcription, translation, virion production) among 68-1 RhCMV/SIV vector-protected RM at necropsy. Our goal is to define the sites and cells hosting replication arrest and whether it involves suppression of SIV gene expression and virion production (analogous to deep latency) and/or an effect on target cells, rendering them resistant to viral infection. Finally, in S.A.3, we will characterize the cellular response (both CD8+ T cells and accessory cell types) to arrested SIV replication in RhCMV/SIV-protected RMs via bulk and single cell transcriptomics and spatial profiling in necropsy tissues. Successful completion of these studies will further our understanding of the unique protection afforded by CMV vectors and facilitate successful clinical translation of CMV-based vectors for a prophylactic HIV vaccine.

项目 1 - 项目摘要 基于表达 SIV 抗原的恒河猴巨细胞病毒 68-1 株的临床前 HIV 疫苗方法 (RhCMV/SIV) 引发细胞免疫反应，严格阻止原发性 SIV 的复制和传播 59% 接种疫苗的恒河猴 (RM) 感染。这些受疫苗保护的 RM 中的绝大多数将 维持这种 SIV 复制停滞（组织中具有复制能力的 SIV 的无病毒血症状态），直到病毒出现 在接下来的 1-3 年内腐烂或彻底灭绝。这种免疫介导的病毒模式 抑制没有先例，尽管精确的病毒学和免疫学机制 这种现象的基础仍然未知，我们已经确定（a）复制抑制功效取决于 关于 RhCMV/SIV 诱导 SIV 特异性 CD8+ T 细胞在主要背景下靶向 SIV 肽 组织相容性复合物 (MHC)-E 而不是 MHC-II 或传统的 MHC-Ia，以及 (b) RM 中 MHC-E 限制的 CD8+ T 细胞反应，通过持续的全血转录组预测疗效 以 IL-15 信号传导为特征的签名。这些数据表明，先天免疫/IL-15 信号传导促进的 MHC- E 限制性 SIV 特异性 CD8+ T 细胞反应介导/协调复制停滞功效，并且 这种模式功效背后的体内功能输出对于这种反应来说是独特的，因此不同于 其他类型的 SIV 特异性 CD8+ T 细胞反应的功能输出。反过来，这表明详细 有效反应与其他疫苗引发的失败 CD8+ T 细胞反应类型的功能比较 介导复制停滞功效（包括通过编程的 MHC-Ia 和 MHC-II 限制性反应） RhCMV/SIV 和 MHC-Ia 限制性反应（通过常规初免-加强疫苗接种）将阐明 复制停滞结果背后的差异。因此，在 S.A.1 中，我们将利用 T 细胞受体 (TCR)- 索引单细胞转录组学以识别区分这些 SIV-的细胞内在转录模式 重要的是，疫苗后期的特异性 CD8+ T 细胞反应。与随后的 SIV 挑战相关 结果（复制停滞与进行性感染）。在 S.A.2 中，我们将从病毒学角度表征早期复制 逮捕，确定组织范围、细胞分布和残留 SIV 的状态（转录、翻译、 尸检时 68-1 RhCMV/SIV 载体保护的 RM 中的病毒颗粒产生）。我们的目标是定义站点和 复制停滞的细胞以及是否涉及抑制 SIV 基因表达和病毒颗粒产生 （类似于深度潜伏期）和/或对靶细胞的影响，使它们对病毒感染具有抵抗力。最后，在 S.A.3，我们将描述对逮捕的 SIV 的细胞反应（CD8+ T 细胞和辅助细胞类型） 通过尸检中的批量和单细胞转录组学和空间分析在 RhCMV/SIV 保护的 RM 中进行复制 组织。成功完成这些研究将进一步加深我们对所提供的独特保护的理解 并促进基于 CMV 的载体成功临床转化为预防性 HIV 疫苗。