Gut Cytotoxic CD4 T cells in HIV-1 Pathogenesis

HIV-1 发病机制中的肠道细胞毒性 CD4 T 细胞

• 批准号: 9925642
• 负责人: Mario Luis Santiago
• 金额: $ 44.57万
• 依托单位: UNIVERSITY OF COLORADO DENVER
• 依托单位国家: 美国
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-01-07 至 2024-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9925642
• 关键词: Apoptotic; Archives; Automobile Driving; Biological; Biology; Biopsy; Blood; Blood Circulation; CCR5 gene; CD3 Antigens; CD4 Positive T Lymphocytes; Cell Death; Cells; Cessation of life; Chronic; Cytokine Signaling; Cytotoxic T-Lymphocytes; Data; Development; Disease; Enteral; Enterobacteriaceae; Epithelial; Epithelium; Exposure to; Flow Cytometry; Frequencies; Functional disorder; Gastrointestinal tract structure; Genes; Gram-Negative Bacteria; Granzyme; Growth; Gut Mucosa; HIV-1; Human; Human Biology; Immune; In Vitro; Individual; Infection; Inflammation; Inflammatory; Inflammatory Response; Knowledge; LAMP-1; Lamina Propria; Leaky Gut; Life Cycle Stages; Ligands; Link; Lymphoid; Lymphoid Tissue; Macaca mulatta; Mediating; Mediator of activation protein; Memory; Microbe; Modeling; Molecular; Molecular Profiling; Mucositis; Mucous Membrane; Outcome; Pathogenesis; Pathogenicity; Pathway interactions; Persons; Phenotype; Plasma; Play; Population; Process; Production; Property; Reporting; Resolution; Role; SIV; Signal Pathway; Signal Transduction; Site; Source; T-Cell Activation; T-Cell Depletion; T-Lymphocyte; Up-Regulation; Viral; Virus Diseases; Work; acute infection; antiretroviral therapy; cell type; cohort; commensal bacteria; comorbidity; cytokine; cytotoxic; dysbiosis; extracellular; gut microbiome; immune activation; in vivo; inhibitor/antagonist; insight; memory CD4 T lymphocyte; microbial; microbiome; mortality; mutant; novel marker; novel therapeutic intervention; perforin; peripheral blood; response; survival prediction; transcription factor; transcriptome; transcriptomics

ABSTRACT HIV-1-associated inflammation and chronic immune activation persist despite suppressive antiretroviral therapy and are strongly linked to the development of comorbidities and increased mortality. The gastrointestinal (GI) tract is likely a major source of chronic inflammation, as early HIV-1 replication and CD4 T cell depletion in the gut results in mucosal inflammation and barrier dysfunction, leading to the translocation of enteric microbes/microbial products into the lamina propria and the systemic circulation. To gain insights into the molecular processes that drive gut-focused chronic immune activation, we profiled the transcriptome of gut CD4+CD8α- T cells exposed to gram-negative enteric bacteria and then infected with HIV-1 ex vivo. Multiple granzyme genes were upregulated following microbe exposure that was further enhanced with HIV-1 infection, suggesting the synergistic induction of CD4 cytotoxic T lymphocyte (CTL) activity. In pilot ex vivo studies, the human gut CD4 CTL phenotype was associated with granzyme (GZ) B expression, TCR signaling, Th1/17 polyfunctionality, reactivity to commensal bacteria and subsets expressing GZA, perforin and/or CD107a. The CD4 CTL phenotype was expressed in CD4 T cells from the gut to a much greater extent than from peripheral blood and lymphoid tissue. Importantly, HIV-1 replicated to a greater extent in gut CD4 CTLs ex vivo. Here, we hypothesize that gut CD4 CTLs are uniquely primed to respond to enteric microbes, are highly susceptible to HIV-1 mediated killing, and play critical roles in mucosal HIV-1 pathogenesis via cytolytic and pro-inflammatory mechanisms. To gain insights on the role of gut CD4 CTLs in HIV-1 pathogenesis, we propose 3 aims. In Aim 1, we will determine if microbiome species and ligands induce gut CD4 CTLs in an MHC-II-dependent manner, obtain insights into gut CD4 CTL origin and function by single-cell transcriptomics, and investigate the stability and fate of these cells ex vivo. In Aim 2, we will determine how HIV-1 infection further augments GZB production in gut CD4 T cells and using our ex vivo lamina propria aggregate culture (LPAC) model, determine if gut CD4 CTLs exacerbate direct and bystander HIV-1-mediated CD4 T cell death via cytolytic mechanisms. In Aim 3, we will evaluate the triggers for GZ secretion and dissect the non-cytolytic, pro-inflammatory properties of GZs secreted by microbe-exposed gut CD4 T cells ex vivo. Importantly, we will explore the in vivo relationship between CD4 CTL frequencies and markers of mucosal and systemic inflammation in archived plasma and gut biopsies from well-characterized cohorts of both untreated and treated persons with chronic HIV-1 infection. Altogether, these studies should provide critical information on this striking gut immune cell subpopulation and its contribution to mucosal inflammation and disease.

抽象的 HIV-1相关的炎症和慢性免疫激活持续存在抑制性抗逆转录病毒 治疗，与合并症的发展和死亡率增加密切相关。这 胃肠道（GI）可能是慢性感染的主要来源，因为早期HIV-1复制和CD4 T 肠道中的细胞部署会导致粘膜注射和屏障功能障碍，导致易位 肠道微生物/微生物产物中的固有层和全身循环。洞悉 我们驱动肠道慢性免疫激活的分子过程，我们介绍了肠道的转录组 CD4+CD8α-T细胞暴露于革兰氏阴性肠细菌，然后被HIV-1外体感染。多种的 在微生物暴露后，将颗粒酶基因上调，并通过HIV-1感染进一步增强 表明CD4细胞毒性T淋巴细胞（CTL）活性的协同诱导。在试验后的研究中， 人肠道CD4 CTL表型与颗粒（Gz）B表达，TCR信号，TH1/17有关 多功能性，对表达GZA，Perforin和/或CD107A的共生细菌的反应性。这 CD4 CTL表型在CD4 T细胞中从肠道中表达的程度要大得多。 血液和淋巴组织。重要的是，HIV-1在肠道CD4 CTL中更大程度地复制。在这里，我们 假设肠道CD4 CTL是独特的，以响应促进微生物，高度 容易受到HIV-1介导的杀戮，并通过 细胞溶解和促炎机制。为了了解肠道​​CD4 CTL在HIV-1中的作用 发病机理，我们提出3个目标。在AIM 1中，我们将确定微生物组和配体是否诱导肠道 以MHC-II依赖性方式CD4 CTL，获得肠道CD4 CTL起源和功能的见解 转录组学，并研究这些细胞的稳定性和命运。在AIM 2中，我们将确定如何 HIV-1感染进一步增强了肠道CD4 T细胞中的GZB产生，并使用我们的离体层 骨料培养（LPAC）模型，确定肠道CD4 CTL是否直接和旁观者HIV-1介导 CD4 T细胞死亡通过细胞溶解机制。在AIM 3中，我们将评估GZ分泌的触发器 由微生物暴露的肠道CD4 T细胞分泌的GZ的非溶解，促炎特性。 重要的是，我们将探讨CD4 CTL频率与粘膜标记和标记之间的体内关系 来自未经处理 并治疗患有慢性HIV-1感染的人。总之，这些研究应提供关键 有关这种引人注目的肠道免疫细胞亚群及其对粘膜的贡献的信息 炎症和疾病。