Targeting Apoptosis and Immune Control of Epstein-Barr Virus Infected Tonsillar B Cells

针对 Epstein-Barr 病毒感染的扁桃体 B 细胞的凋亡和免疫控制

• 批准号: 9237256
• 负责人: Micah A. Luftig
• 金额: $ 43.79万
• 依托单位: DUKE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-03-04 至 2021-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9237256
• 关键词: Accounting; Adult; Antigen-Presenting Cells; Apoptosis; B Cell Proliferation; B-Cell Lymphomas; B-Lymphocytes; Blood Cells; CD8-Positive T-Lymphocytes; Cancer Etiology; Cell Survival; Cells; Complex; Data; Disease; Epithelial Cells; Epstein-Barr Virus Infections; Epstein-Barr Virus Nuclear Antigens; Epstein-Barr Virus latency; GTP-Binding Protein alpha Subunits, Gs; Gene Expression; Genetic Transcription; Goals; HIV; HIV Infections; HIV-1; Hairy Leukoplakia; Haplotypes; Human; Human Herpesvirus 4; Immune; Immune Evasion; Immunosuppression; In Vitro; Individual; Infection; Lead; Life Cycle Stages; Lymphoid Tissue; Lymphoma; Lytic; MHC Class I Genes; Maintenance; Mediating; Membrane Proteins; Messenger RNA; Mitochondria; Modeling; Mouth Diseases; Oral; Oral Ulcer; Oral cavity; Pathogenesis; Periodontitis; Phase; Primary Infection; Process; Proteins; Research; Resistance; Saliva; Signal Pathway; Signal Transduction; T-Lymphocyte; Testing; Tonsil; Transplantation; Up-Regulation; Viral; Viral Genes; Virus; Virus Diseases; Virus Latency; adaptive immune response; base; c-myc Genes; cohort; gammaherpesvirus; immunogenic; in vivo; infected B cell; killings; latent gene expression; lymphoblastoid cell line; pathogen; peripheral blood; prevent; programs; protein expression; public health relevance; therapeutic target; transforming virus

 DESCRIPTION (provided by applicant): Epstein-Barr virus (EBV) is a gamma-herpesvirus that infects nearly 95% of adults worldwide. A potent adaptive immune response against the virus prevents disease in the majority of those infected. However, immune suppression, such as during HIV-1 infection, can promote latent EBV-driven B-cell lymphomas. It is our ultimate goal to define the mechanisms by which EBV establishes latency and how these processes go awry leading to disease. In this proposal, we aim to characterize a newly described early latent phase of EBV infection in primary tonsillar B cells and the mechanisms of EBV-mediated survival and immune evasion important for establishing and maintaining the latency reservoir. It is our central hypothesis that EBV promotes B-cell proliferation and survival through its EBV nuclear antigen (EBNA) proteins during the first two weeks of infection; while later during infection the EBNAs and latent membrane protein 1 (LMP1) are required for survival in the immortalized state. We propose that the importance of this biphasic EBV latent gene expression program is to prevent early recognition of EBV-infected B cells by cytotoxic T cells promoting efficient seeding of the long-term latently infected cell reservoir. We have formulated our central hypothesis based on preliminary data characterizing the temporal viral and host gene expression programs and survival mechanisms following EBV infection of peripheral blood B cells where we found that early after tonsillar B-cell infection, the viral EBNA proteins are expressed at high levels in the absence of appreciable levels of the viral LMPs. Importantly, this latency type (IIb) has been observed in EBV-associated post-transplant and HIV lymphomas. Therefore, the rationale for this proposed research is that understanding the mechanism supporting latency IIb infection by EBV may identify critical therapeutic targets for EBV-associated lymphomas and may inform our understanding of the temporal dynamics of EBV infection and the adaptive immune response to this ubiquitous orally-transmitted pathogen. We plan to test our hypothesis and complete the objectives outlined in this proposal through the following three specific aims: 1) Determine the mechanism regulating the switch in viral gene expression from early, EBNAs only (latency IIb), through late, EBNAs + LMPs (latency III), phases of primary tonsillar B-cell infection, 2) Determine the mechanism of early, NFκB-independent and late, NFκB- dependent EBV-infected tonsillar B-cell survival, and 3) Define the consequences of low LMP1/NFκB activity on EBV-infected B-cell peripheral blood and tonsillar B-cell immune recognition, activation, and killing b T cells.

 描述（由申请人提供）：EB 病毒 (EBV) 是一种 γ 疱疹病毒，可感染全世界近 95% 的成年人。针对该病毒的有效适应性免疫反应可以预防大多数感染者的疾病。例如在 HIV-1 感染期间，可以促进潜伏性 EBV 驱动的 B 细胞淋巴瘤。我们的最终目标是确定 EBV 建立潜伏期的机制以及这些过程如何出错导致。在本提案中，我们的目标是描述新描述的原发性扁桃体 B 细胞中 EBV 感染的早期潜伏期，以及 EBV 介导的存活和免疫逃避的机制，这对于建立和维持潜伏期病毒库至关重要。在感染的前两周，EBV 通过其 EBV 核抗原 (EBNA) 蛋白促进 B 细胞增殖和存活；而在感染后期，EBNA 和潜伏膜蛋白 1 (LMP1) 是永生化状态下生存所必需的。提出这种双相 EBV 潜伏基因表达程序的重要性是防止细胞毒性 T 细胞早期识别 EBV 感染的 B 细胞，从而促进长期潜伏感染细胞库的有效播种。我们根据初步数据制定了我们的中心假设。表征了 EBV 感染外周血 B 细胞后的时间病毒和宿主基因表达程序以及生存机制，我们发现在扁桃体 B 细胞感染后早期，病毒 EBNA 蛋白在 重要的是，这种潜伏型 (IIb) 已在 EBV 相关移植后和 HIV 淋巴瘤中观察到。因此，这项研究的基本原理是了解支持 EBV 潜伏型 IIb 感染的机制。可能会确定 EBV 相关淋巴瘤的关键治疗靶点，并可能让我们了解 EBV 感染的时间动态以及对这种普遍存在的口腔传播病原体的免疫反应。我们计划检验我们的假设并完成。通过以下三个具体目标来实现本提案中概述的目标： 1) 确定调节病毒基因表达转换的机制，从早期、仅 EBNA（潜伏期 IIb）到晚期、EBNA + LMP（潜伏期 III）、原发性扁桃体阶段B 细胞感染，2) 确定早期、不依赖 NFκB 和晚期、依赖 NFκB 的 EBV 感染扁桃体 B 细胞存活的机制，以及 3) 定义LMP1/NFκB 活性低对 EBV 感染的 B 细胞外周血和扁桃体 B 细胞免疫识别、激活和杀伤 b T 细胞的影响。