Project 2: Characterization of the in vivo T cell (and overall immune) interception of primary SIV infection after vaccination with differentially response programmed RhCMV/SIV vectors

项目 2：用差异反应编程的 RhCMV/SIV 载体接种疫苗后，体内 T 细胞（和整体免疫）拦截原发性 SIV 感染的表征

• 批准号: 10709017
• 负责人: Scott G Hansen
• 金额: $ 55.93万
• 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/10709017
• 关键词: Autopsy; Bar Codes; Bioinformatics; Biopsy; CD8-Positive T-Lymphocytes; Cells; Cellular Indexing of Transcriptomes and Epitopes by Sequencing; Characteristics; Cytomegalovirus; Data; Development; Dose; Epitopes; Exhibits; Genetic Transcription; Goals; HIV vaccine; Immune; Immune response; Immunologics; Infection; Innate Immune Response; Intercept; Interleukin-15; Link; Macaca mulatta; Major Histocompatibility Complex; Mediating; Memory; Modality; Modeling; Mucous Membrane; Pathogenicity; Pattern; Phenotype; Process; Rhesus; SIV; SIV Vaccines; Sampling; Schedule; Signal Transduction; Site; T cell receptor repertoire sequencing; T cell response; T-Cell Receptor; T-Lymphocyte; Technology; Tissues; Vaccinated; Vaccination; Vaccinee; Vaccines; Viral; Viremia; Virus; Virus Activation; cell type; clinical translation; genetic manipulation; high dimensionality; immune activation; in vivo; indexing; insight; predictive signature; programs; response; transcriptome; transcriptome sequencing; transcriptomics; unvaccinated; vector

PROJECT 2 - PROJECT SUMMARY Vaccination of Rhesus macaques (RMs) with SIV insert-expressing 68-1 Rhesus Cytomegalovirus vectors (RhCMV/SIV) elicits an immune response that in 59% of vaccinees can intercept and effectively arrest an early spreading primary SIV infection. This unique pattern of “replication arrest” efficacy has been linked to three 68- 1 RhCMV/SIV immune characteristics, including its ability to generate and maintain: 1) high magnitude, circulating and tissue-based, effector memory-biased CD8+ T cell responses, 2) major histocompatibility complex (MHC)-E-restricted SIV-specific CD8+ T cell responses and 3) in RMs with MHC-E-restricted CD8+ T cell responses, a protection-predictive innate immune transcriptional response to vaccination that includes a central IL-15 signaling component; however, the specific immune mechanism(s) underlying replication arrest protection are unknown. RhCMV/SIV vectors can now be programmed by genetic manipulation to elicit SIV-specific CD8+ T cell responses that are restricted by MHC-E-only, MHC-II-only and MHC-Ia-only, and while the latter 2 response types are similar in magnitude and phenotype to the MHC-E-restricted responses, they, as well as conventional prime-boost vaccine elicited MHC-Ia-restricted CD8+ T cell responses, are unable to mediate SIV replication arrest. This indicates that the protective (IL-15/innate-modulated) MHC-E-restricted SIV-specific CD8+ T cells must manifest a different response upon interception of primary SIV infection than the other T cell response types, possibly being more efficient in detecting and responding to SIV-infected cells in vivo and/or manifesting a different (more effective) functional program upon infected cell recognition. In this project, we will use sophisticated `omics technologies that enable detailed characterization of tissue immune responses (including specific analyses of T cell receptor-defined, SIV-specific CD8+ T cells) to define these differences in vivo in the actual RM tissues hosting an early spreading SIV infection. In S.A.1, we will define the systemic viral and immune activation trajectories of unvaccinated vs. (long-term, previously protected and functionally cured) 68-1 RhCMV/SIV vaccinated RMs by analysis of serial necropsies with the goal identifying the optimal post challenge timepoint(s) to study the cellular immune interception of viral spread prior to progressive viremia or stable establishment of replication arrest. In S.A.2, we will use this optimized RM model to identify the unique characteristics of RhCMV/SIV-elicited MHC-E-restricted CD8+ T cell responses in vaccinated naïve RMs that mediate SIV replication arrest efficacy by comparison of the viral:immune intercept of these responses vs. MHC- II-only and MHC-Ia-only SIV-specific CD8+ T cell responses elicited in naïve RMs by differentially programmed RhCMV vectors and vs. MHC-Ia-restricted CD8+ T cell responses elicited by the conventional ChAdOx1/MVA vaccine. These contrasts will provide important insight into the immune processes responsible for replication arrest efficacy and facilitate development of immune mechanism-based correlates of efficacy that will guide clinical translation of a CMV-based HIV vaccine.

项目 2 - 项目摘要 使用表达 SIV 插入片段的 68-1 恒河猴巨细胞病毒载体对恒河猴 (RM) 进行疫苗接种 (RhCMV/SIV) 会引发免疫反应，59% 的疫苗接种者可以拦截并有效阻止早期免疫反应。 传播原发性 SIV 感染。这种独特的“复制抑制”功效模式与三个 68- 1 RhCMV/SIV 免疫特性，包括其产生和维持的能力：1) 高强度， 基于循环和组织的、效应记忆偏向的 CD8+ T 细胞反应，2) 主要组织相容性复合体 (MHC)-E 限制性 SIV 特异性 CD8+ T 细胞反应和 3) 具有 MHC-E 限制性 CD8+ T 细胞的 RM 反应，对疫苗接种的保护预测先天免疫转录反应，其中包括一个中枢 IL-15信号传导成分；然而，复制抑制保护背后的特定免疫机制 未知。 RhCMV/SIV 载体现在可以通过基因操作进行编程，以引发 SIV 特异性 CD8+ T 细胞反应受仅 MHC-E、仅 MHC-II 和仅 MHC-Ia 限制，而后 2 反应类型在幅度和表型上与 MHC-E 限制性反应相似，它们以及 传统的初免-加强疫苗引发 MHC-Ia 限制的 CD8+ T 细胞反应，无法介导 SIV 复制停滞。这表明保护性（IL-15/先天调节）MHC-E 限制性 SIV 特异性 CD8+ 在拦截原发性 SIV 感染后，T 细胞必须表现出与其他 T 细胞不同的反应 反应类型，可能更有效地检测和响应体内 SIV 感染的细胞和/或 在识别受感染的细胞后表现出不同的（更有效的）功能程序。在这个项目中，我们将 使用复杂的“组学”技术来详细表征组织免疫反应 （包括对 T 细胞受体定义的、SIV 特异性 CD8+ T 细胞的具体分析）来定义这些差异 体内存在早期传播的 SIV 感染的实际 RM 组织。在 S.A.1 中，我们将定义系统性病毒 未接种疫苗与（长期、先前受保护和功能性治愈）的免疫激活轨迹 通过连续尸检分析 68-1 RhCMV/SIV 接种的 RM，目的是确定最佳位置 挑战时间点来研究进行性病毒血症之前细胞免疫对病毒传播的拦截或 复制停滞的稳定建立。在S.A.2中，我们将使用这个优化的RM模型来识别独特的 在接种过疫苗的 RM 中，RhCMV/SIV 引发的 MHC-E 限制性 CD8+ T 细胞反应的特征 通过比较这些反应与 MHC- 的病毒：免疫拦截来介导 SIV 复制停滞功效 仅 II 和仅 MHC-Ia 的 SIV 特异性 CD8+ T 细胞反应通过差异编程在幼稚 RM 中引发 RhCMV 载体和与由传统 ChAdOx1/MVA 引发的 MHC-Ia 限制性 CD8+ T 细胞反应 疫苗。这些对比将为了解负责复制的免疫过程提供重要的见解 阻止功效并促进基于免疫机制的功效相关性的发展，这将指导 基于 CMV 的 HIV 疫苗的临床转化。