EBV LMP1/LMP2A Proteins Promote Hodgkin-like Lymphomas in Humanized Mice

EBV LMP1/LMP2A 蛋白促进人源化小鼠霍奇金样淋巴瘤的发生

• 批准号: 10152365
• 负责人: Shannon Celeste Kenney
• 金额: $ 38.15万
• 依托单位: UNIVERSITY OF WISCONSIN-MADISON
• 依托单位国家: 美国
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-06-13 至 2023-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10152365
• 关键词: AIDS-Related Hodgkin' s Lymphoma; AIDS-Related Lymphoma; Acquired Immunodeficiency Syndrome; Attenuated; Autocrine Communication; Automobile Driving; B-Cell Antigen Receptor; B-Cell Lymphomas; B-Lymphocytes; CD4 Positive T Lymphocytes; Cell Line; Cells; Collagen; DDR1 gene; Development; EBNA2 protein; Environment; Epstein-Barr Virus Infections; Epstein-Barr Virus latency; Goals; Growth; HIV Infections; Hodgkin Disease; Human; Human Herpesvirus 4; Immunocompetence; Immunocompromised Host; Immunosuppression; In Vitro; Inflammatory; LMP1; Laboratories; Lead; Lymphoma; Lymphoma cell; Malignant Neoplasms; Membrane Proteins; Modeling; PDGFA gene; PDGFRA gene; Paracrine Communication; Pathway interactions; Patients; Phenotype; Proteins; Receptor Protein-Tyrosine Kinases; Research; Role; Signal Pathway; Signal Transduction; T-Lymphocyte; TNFRSF5 gene; Transcription Coactivator; Tumor-Derived; Umbilical Cord Blood; Viral Proteins; Virus; Virus Latency; cell growth; humanized mouse; immunogenic; improved; in vitro Model; in vivo; in vivo Model; insight; mouse model; mutant; neoplastic cell; notch protein; novel; novel therapeutics; overexpression; public health relevance; tumor; tumor growth; tumor microenvironment

PROJECT SUMMARY/ABSTRACT Epstein-Barr virus is an important cause of AIDS-related lymphomas (ARLs) world-wide, including Hodgkin lymphomas (HLs) that are driven by the EBV latent membrane proteins LMP1 (a CD40 mimic) and LMP2A (a BCR mimic), in conjunction with a supportive tumor microenvironment. Although the EBV protein EBNA2 (which mimics notch signaling) is required for EBV-induced transformation of B cells in vitro, cells that express EBNA2 have the “type III” form of viral latency, which is highly immunogenic. Thus, most EBV-infected human lymphomas (including ARLs in cART-treated patients) do not express EBNA2. However, there is currently no in vivo or in vitro model available to study how EBV infection can cause lymphomas in the absence of EBNA2 expression, and the only EBV+ HL cell line, L591, has switched to type III latency. Increasing evidence suggests that HIV infection collaborates with EBV to induce lymphomas not only by inducing immunosuppression, but by creating a pro-inflammatory microenvironment that promotes tumors with more stringent forms of EBV latency (such as the “type II” form that occurs in HLs) that do not express EBNA2. Our lab has developed a novel cord blood-humanized mouse model which provides a highly supportive CD4 T cell-rich environment that allows certain EBV mutants previously considered “non-transforming” in vitro to induce lymphomas in vivo. Our new exciting preliminary results reveal that a naturally occurring EBNA2-deleted EBV strain (P3HR1) that is completely non-transforming in vitro causes Hodgkin-like lymphomas that express LMP1 and LMP2A in this model. Furthermore, our preliminary results suggest that similar to human HLs, lymphomas induced by EBNA2- deleted EBV are heavily infiltrated with collagen, express the pro-survival collagen-stimulated receptor tyrosine kinase DDR1, and have activated PDGFRA and notch-1 signaling. Thus, we believe we have created the first in vivo model for EBV-induced Hodgkin lymphoma. In this proposal, we will dissect the roles of the EBV proteins LMP1 and LMP2A, as well as the tumor microenvironment, in driving lymphomas induced by EBNA2-deleted EBV in humanized mice. We hypothesize that both LMP1 and LMP2A, as well as CD4 T cell- and collagen- derived signals in the microenvironment, are required for the growth of these lymphomas. In Aim 1, we will compare the phenotypes of wild-type (WT) versus EBNA2-deleted (Akata strain) EBV in humanized mouse models, and identify paracrine and/or autocrine signaling pathways (derived from T cells, B cells and/or collagen) that compensate for loss of EBNA2 expression both in vivo and in L591 HL cells in vitro. In Aim 2, we will define the roles of LMP1 and LMP2A on tumor cell growth, and in regulating the tumor microenvironment, in both the CBH model in vivo and in L591 cells in vitro. In Aim 3, we will determine whether inhibiting notch, PDGFRA and/or DDR1 signaling attenuates the growth of lymphomas induced by WT virus and/or EBNA2-deleted virus in humanized mice or in L591 cells in vitro. The results of these studies should provide key insights into the mechanism(s) by which LMP1 and LMP2A promote AIDS-related Hodgkin lymphomas, and elucidate how the tumor microenvironment cooperates with type II latent EBV infection to induce human lymphomas in vivo when EBNA2 expression is shut off.

项目概要/摘要 Epstein-Barr 病毒是全世界艾滋病相关淋巴瘤 (ARL) 的重要病因，包括霍奇金淋巴瘤 由 EBV 潜伏膜蛋白 LMP1（CD40 模拟物）和 LMP2A（CD40 模拟物）驱动的淋巴瘤 (HL) BCR 模拟），与支持性肿瘤微环境相结合。虽然 EBV 蛋白 EBNA2（ EBV 诱导的体外 B 细胞转化（表达 EBNA2 的细胞）需要模拟缺口信号传导 具有“III 型”病毒潜伏期，具有高度免疫原性。因此，大多数感染 EBV 的人 淋巴瘤（包括接受 cART 治疗的患者中的 ARL）不表达 EBNA2。不过目前国内还没有 可用于研究 EBV 感染在没有 EBNA2 的情况下如何导致淋巴瘤的体内或体外模型 表达，唯一的 EBV+ HL 细胞系 L591 已转变为 III 型潜伏期。越来越多的证据表明 HIV 感染与 EBV 协同作用不仅通过诱导免疫抑制，还通过 创建促炎性微环境，促进具有更严格形式的 EBV 潜伏期的肿瘤 （例如 HL 中出现的“II 型”形式）不表达 EBNA2。我们的实验室开发了一种新型绳索 血液人源化小鼠模型提供了高度支持性的富含 CD4 T 细胞的环境，使 某些 EBV 突变体以前被认为在体外“非转化”，但在体内诱导淋巴瘤。我们的新 令人兴奋的初步结果表明，天然存在的 EBNA2 缺失的 EBV 毒株 (P3HR1) 体外完全非转化会导致表达 LMP1 和 LMP2A 的霍奇金样淋巴瘤 模型。此外，我们的初步结果表明，与人类 HL 类似，EBNA2- 诱导的淋巴瘤 缺失的 EBV 被胶原蛋白大量浸润，表达促存活胶原蛋白刺激受体酪氨酸 激酶 DDR1，并激活 PDGFRA 和 notch-1 信号传导。因此，我们相信我们已经创造了第一个 EBV 诱导的霍奇金淋巴瘤体内模型。在本提案中，我们将剖析 EBV 蛋白的作用 LMP1 和 LMP2A 以及肿瘤微环境在驱动 EBNA2 缺失诱导的淋巴瘤中的作用 人源化小鼠中的 EBV。我们假设 LMP1 和 LMP2A 以及 CD4 T 细胞和胶原蛋白 微环境中的衍生信号是这些淋巴瘤生长所必需的。在目标 1 中，我们将 比较人源化小鼠中野生型 (WT) 与 EBNA2 缺失（Akata 株）EBV 的表型 模型，并识别旁分泌和/或自分泌信号通路（源自 T 细胞、B 细胞和/或胶原蛋白） 补偿体内和体外 L591 HL 细胞中 EBNA2 表达的损失。在目标 2 中，我们将定义 LMP1和LMP2A在肿瘤细胞生长和调节肿瘤微环境中的作用 体内 CBH 模型和体外 L591 细胞。在目标3中，我们将确定是否抑制Notch、PDGFRA 和/或 DDR1 信号减弱由 WT 病毒和/或 EBNA2 缺失病毒诱导的淋巴瘤的生长 在人源化小鼠或体外 L591 细胞中。这些研究的结果应该为以下问题提供重要见解： LMP1 和 LMP2A 促进艾滋病相关霍奇金淋巴瘤的机制，并阐明如何 当肿瘤微环境与 II 型潜伏 EBV 感染配合时，在体内诱导人淋巴瘤 EBNA2 表达被关闭。