GIF regulation of B cells and CD4 cells

GIF 对 B 细胞和 CD4 细胞的调节

• 批准号: 6674735
• 负责人: KATSUJI SUGIE
• 金额: $ 32.38万
• 依托单位: LA JOLLA INSTITUTE FOR IMMUNOLOGY
• 依托单位国家: 美国
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-09-15 至 2004-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6674735
• 关键词: B cell receptor; B lymphocyte; T cell receptor; antigen presentation; cell cell interaction; cell differentiation; crosslink; cytokine receptors; genetic library; genetically modified animals; hamsters; helper T lymphocyte; humoral immunity; immunoregulation; laboratory mouse; laboratory rat; lymphokines

DESCRIPTION (provided by applicant): GIF is a 13-kDa cytokine discovered in the course of the study on IgE synthesis. It is encoded by a single gene in the genome and its nucleotide sequence is identical is that published for macrophage migration inhibitory factor (MIF). MIF(GIF)-/- mice show enhanced susceptibility to Leishmania major. These mice are incapable of developing the experimental colitis. These findings support the notion that GIF is involved inactivating the innate immune system. GIF protein is expressed in the cytosol of hematopoietic and nonhematopoietic cells. GIF secreted from T cells is cysteinylated at C60, whereas that contained in the cytosol of the same cells is unmodified. The modification at C60 is required for the capability of this cytokine to bind to target cells, to inhibit BCR-mediated uptake of antigen, and to inhibit IL-4 secretion from CD4 cells. Binding assays demonstrated that GIF receptors are expressed on T and B cells after these cells are activated, but not on macrophage and dendritic cell lines. Chemical crosslinking experiments suggest that GIF binds to a 50-52 kDa cell surface protein. GIF-/- mice show enhanced antibody responses to T-dependent antigens. GIF-/- CD4 cells were polarized toward a Th2 phenotype as compared with wild type cells. To clarify the role of this cytokine in T-dependent and -independent humoral responses, GIF+/+ and -/- mice crossed to BALB/c and those to B6 will be immunized with various antigens and adjuvants. The role of GIF in cognate T-B interaction will be analyzed in vitro and in vivo using TCR Tg mice and BCR Tg mice on GIF+/+ and -/- backgrounds. The biochemical mechanisms by which GIF regulates BCR-mediated antigen presentation will be analyzed. TCR Tg GIF+/+ and -/- mice will be compared for the signals that regulate Th differentiation. These mice will also be used to determine the involvement of the innate immunity in the regulation of Th differentiation. The functional relevance of GIF-dependent Th development will be addressed in the mouse model of allergic airway inflammation. Finally, using C60-modified rGIF, GIF receptor will be molecularly characterized. These experiments will be useful to determine whether this cytokine directly regulates innate immunity or antigen-specific immunity and whether the form secreted from T cells or that contained in the cytosol plays an important role in its function. This project will fill a critical gap in our knowledge in cytokine biology.

描述（申请人提供）：GIF是在IgE合成研究过程中发现的一种13-kDa细胞因子。它由基因组中的单个基因编码，其核苷酸序列与已公布的巨噬细胞迁移抑制因子（MIF）的核苷酸序列相同。 MIF(GIF)-/- 小鼠对大型利什曼原虫的易感性增强。这些小鼠不能发展为实验性结肠炎。这些发现支持 GIF 与先天免疫系统失活有关的观点。 GIF 蛋白在造血细胞和非造血细胞的细胞质中表达。 T 细胞分泌的 GIF 在 C60 处被半胱氨酸化，而包含在相同细胞的胞浆中的 GIF 则未经修饰。 C60 处的修饰是该细胞因子与靶细胞结合、抑制 BCR 介导的抗原摄取以及抑制 CD4 细胞分泌 IL-4 的能力所必需的。结合测定表明，T 细胞和 B 细胞被激活后，GIF 受体在这些细胞上表达，但在巨噬细胞和树突细胞系上不表达。化学交联实验表明 GIF 与 50-52 kDa 的细胞表面蛋白结合。 GIF-/-小鼠表现出对T依赖性抗原的增强的抗体反应。与野生型细胞相比，GIF-/- CD4 细胞极化为 Th2 表型。为了阐明这种细胞因子在 T 依赖性和非依赖性体液反应中的作用，用各种抗原和佐剂对与 BALB/c 杂交的 GIF+/+ 和 -/- 小鼠以及与 B6 杂交的小鼠进行免疫。 GIF 在同源 T-B 相互作用中的作用将使用 TCR Tg 小鼠和 BCR Tg 小鼠在 GIF+/+ 和 -/- 背景下进行体外和体内分析。将分析 GIF 调节 BCR 介导的抗原呈递的生化机制。将比较 TCR Tg GIF+/+ 和 -/- 小鼠调节 Th 分化的信号。这些小鼠还将用于确定先天免疫在 Th 分化调节中的作用。 GIF 依赖性 Th 发育的功能相关性将在过敏性气道炎症小鼠模型中得到解决。最后，使用 C60 修饰的 rGIF，对 GIF 受体进行分子表征。这些实验将有助于确定这种细胞因子是否直接调节先天免疫或抗原特异性免疫，以及 T 细胞分泌的形式或细胞质中包含的形式是否在其功能中发挥重要作用。该项目将填补我们在细胞因子生物学知识方面的一个关键空白。

项目成果

CD4 cell-secreted, posttranslationally modified cytokine GIF suppresses Th2 responses by inhibiting the initiation of IL-4 production.

CD4 细胞分泌的、翻译后修饰的细胞因子 GIF 通过抑制 IL-4 产生的起始来抑制 Th2 反应。

• DOI: 10.1073/pnas.0810035105
• 发表时间: 2008
• 期刊: Proceedings of the National Academy of Sciences of the United States of America
• 影响因子: 11.1
• 作者: Kim-Saijo,Misa;Janssen,EdithM;Sugie,Katsuji
• 通讯作者: Sugie,Katsuji