Mechanisms of B cell specific IL-35 expression in cancer.

癌症中 B 细胞特异性 IL-35 表达的机制。

• 批准号: 9910621
• 负责人: Daniel E Michaud
• 金额: $ 3.39万
• 依托单位: UNIV OF NORTH CAROLINA CHAPEL HILL
• 依托单位国家: 美国
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-01-01 至 2021-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9910621
• 关键词: Adaptor Signaling Protein; Address; Adoptive Transfer; Agammaglobulinaemia tyrosine kinase; Antigens; Autoimmune Diseases; B-Cell Activation; B-Lymphocytes; CD19 gene; CD8-Positive T-Lymphocytes; Cancer Etiology; Cell Line; Cell Nucleus; Cells; Cellular biology; Cessation of life; Data; Diagnosis; Disease; Endosomes; Exposure to; Goals; Growth; Immune; Immunosuppression; Immunotherapeutic agent; Immunotherapy; Implant; In Vitro; Infiltration; Injections; Interleukins; Malignant Neoplasms; Malignant neoplasm of pancreas; Mediating; Modality; Modeling; Mus; MyD88 protein; Pancreatic Ductal Adenocarcinoma; Pathogenicity; Pathway interactions; Patient-Focused Outcomes; Patients; Phosphotransferases; Production; Receptor Activation; Receptor Cell; Receptor Protein-Tyrosine Kinases; Receptor Signaling; Receptors, Antigen, B-Cell; Regulation; Research; Research Proposals; Signal Pathway; Signal Transduction; Signaling Molecule; Specificity; Structure of beta Cell of islet; Survival Rate; T cell response; T-Lymphocyte; TLR2 gene; TLR7 gene; Testing; Therapeutic; Toll-Like Receptor Pathway; Toll-like receptors; Training; Tumor Immunity; United States; Up-Regulation; Western Blotting; anti-tumor immune response; base; cancer therapy; career; cytokine; design; experience; immunoregulation; improved; in vivo; in vivo monitoring; inhibitor/antagonist; insight; mouse model; neutralizing antibody; novel; pancreatic neoplasm; pancreatic tumorigenesis; treatment response; tumor; tumor growth; tumor microenvironment; tumorigenic

Project Abstract Pancreatic Ductal Adenocarcinoma (PDA) is the most commonly diagnosed form (~90%) of pancreatic cancer with a dismal 5-year survival rate of ~8%. PDA features a prominent pro-tumorigenic microenvironment rich in immunosuppressive cells that inhibit functions of anti-tumor immunity. Current immunotherapeutic approaches have been unsuccessful in improving PDA patient outcomes, leaving a need for a better understanding of the immunomodulatory signaling mechanisms within pancreatic tumor microenvironment. We have identified infiltrating regulatory B cells as being key contributors to pancreatic tumorigenesis through their expression of the regulatory cytokine IL-35, which directly inhibits anti-tumor immune responses. The mechanisms that cause B cells to produce IL-35 in cancer and promote pancreatic tumor growth are not known. Using a mouse model harboring a monoclonal fixed B cell receptor (BCR), or mice with a B cell-specific deletion of the Toll-Like Receptor (TLR) adaptor protein MyD88, I found that orthotopically implanted pancreatic tumors were drastically reduced in size as compared to WT mice. I have also conducted in vitro analysis of TLR and BCR activation and found that co-stimulation of endosomal TLRs and the BCR leads to a robust increase of IL-35 expression in B cells. Based on my preliminary data, I hypothesize that cancer-driven upregulation of IL-35 in B cells is dependent on crosstalk between BCR and endosomal TLRs, which promotes pancreatic tumor growth through immunosuppression. I propose two specific aims to test my hypothesis. In Aim 1, I will determine how BCR and endosomal TLR signaling via Bruton's tyrosine kinase (BTK) contributes to expression of IL-35 expression in B cells, using analysis of signaling pathways in primary regulatory B cells and established B cell lines. In Aim 2, I will investigate how activation of both BCR and TLR signaling in B cells promotes PDA tumor growth in vivo. To accomplish this task, I will analyze mouse models expressing a fixed BCR specificity with or without specific antigen exposure, mouse models lacking MyD88 signaling in B cells, as well as a cross of the two models. Our proposed research will provide an understanding of a previously uncharacterized facet of B cell-mediated function in PDA and use state-of-the-art PDA murine models to test strategies that block immune suppressive pathways. Ultimately, I anticipate my findings will reveal a targetable mechanism to inhibit B cell-mediated immunosuppression in pancreatic tumors and provide a multi-faceted training experience to help advance my scientific career.

项目摘要 胰腺导管腺癌 (PDA) 是最常见的胰腺癌诊断形式 (~90%) 5 年生存率约为 8%。 PDA 具有突出的促肿瘤微环境，富含 抑制抗肿瘤免疫功能的免疫抑制细胞。目前的免疫治疗方法 未能成功改善 PDA 患者的预后，因此需要更好地了解 胰腺肿瘤微环境中的免疫调节信号机制。我们已经确定 浸润性调节性 B 细胞通过其表达而成为胰腺肿瘤发生的关键因素 调节细胞因子IL-35，直接抑制抗肿瘤免疫反应。引起的机制 B 细胞在癌症中产生 IL-35 并促进胰腺肿瘤生长尚不清楚。使用鼠标模型 携带单克隆固定 B 细胞受体 (BCR) 的小鼠，或具有 B 细胞特异性 Toll 样缺失的小鼠 受体（TLR）接头蛋白MyD88，我发现原位植入的胰腺肿瘤急剧增加 与 WT 小鼠相比，体型减小。我还进行了 TLR 和 BCR 激活的体外分析 发现内体 TLR 和 BCR 的共刺激导致 B 中 IL-35 表达的强劲增加 细胞。根据我的初步数据，我假设 B 细胞中癌症驱动的 IL-35 上调依赖于 BCR 和内体 TLR 之间的串扰，通过促进胰腺肿瘤生长 免疫抑制。我提出了两个具体目标来检验我的假设。在目标 1 中，我将确定 BCR 和 通过布鲁顿酪氨酸激酶 (BTK) 的内体 TLR 信号传导有助于 B 中 IL-35 的表达 细胞，使用初级调节 B 细胞和已建立的 B 细胞系中的信号通路分析。在目标 2 中，我 将研究 B 细胞中 BCR 和 TLR 信号传导的激活如何促进体内 PDA 肿瘤生长。到 完成这项任务后，我将分析表达固定 BCR 特异性的小鼠模型，无论是否具有特定的 BCR 特异性 抗原暴露、B 细胞中缺乏 MyD88 信号传导的小鼠模型，以及两种模型的交叉。我们的 拟议的研究将提供对 B 细胞介导的先前未表征的方面的理解 PDA 中的功能并使用最先进的 PDA 小鼠模型来测试阻断免疫抑制的策略 途径。最终，我预计我的发现将揭示一种抑制 B 细胞介导的靶向机制 胰腺肿瘤的免疫抑制，并提供多方面的培训经验，以帮助推进我的 科学事业。