Role of Nuclear Factor TOX in Germinal Center Reactions

描述（由申请方提供）：高亲和力保护性抗体应答的产生需要T和B细胞在称为生发中心的次级淋巴组织的专门区域中协作。了解这些细胞相互作用的调节对于疫苗开发和了解生殖中心淋巴细胞在肿瘤发展和自身免疫中的作用是重要的。滤泡辅助性T细胞（TFH）是能够迁移到滤泡中并将辅助信号传递到B细胞的特化CD4 T细胞，因此在体液免疫应答的功能成熟中发挥关键作用。基因表达的总体分析表明，生发中心B细胞和TFH都具有独特的基因表达模式，这使它们与其他幼稚和活化淋巴细胞亚群区分开来。据报道，在生发中心B细胞和TFH中特异性表达的基因之一编码TOX，TOX是啮齿动物和人类之间高度保守的蛋白质，在我们的实验室中首次被鉴定为T细胞发育的调节因子。我们已经生产了TOX转基因小鼠和全面和条件性TOX缺陷小鼠，并已表明TOX是CD4 T细胞谱系发育所必需的。使用这些转基因动物的组合，我们建议在这里，以确定是否TOX也发挥了作用，在生发中心的反应。我们的方法使我们能够区分毒素缺乏对B和T细胞的影响。因此，将条件性TOX缺陷小鼠与在B细胞谱系中表达Cre重组酶的小鼠交配，将用于寻找免疫后生殖中心B细胞形成和功能的缺陷。提出了两种互补的方法来研究类似的作用，TOX在TFH的发展和功能;互补的全球TOX缺陷小鼠与胸腺表达的TOX转基因和在体外Cre介导的删除的Tox位点的CD4 + T细胞，随后测试TFH的发展和功能在体内。为了补充这些研究，我们还建议产生TOX报告基因敲入小鼠品系，这将使我们能够在免疫应答期间跟踪活细胞和体内TOX的表达。 公共卫生相关性：保护性抗体介导的免疫应答需要T和B淋巴细胞在称为生发中心的次级淋巴组织的专门区域中相互作用。了解这些相互作用的调节对于疫苗开发和了解生殖中心淋巴细胞在肿瘤发展和自身免疫中的作用是重要的。这项研究计划旨在了解一种在啮齿动物和人类中高度保守的特定核蛋白在调节这些生发中心反应中的作用。

DESCRIPTION (provided by applicant): The generation of a high affinity protective antibody response requires T and B cell collaboration in specialized areas of secondary lymphoid tissue known as germinal centers. Understanding the regulation of these cellular interactions is important for vaccine development and for understanding the role of germinal center lymphocytes in tumor development and autoimmunity. T follicular helper cells (TFH) are specialized CD4 T cells that are able to migrate into follicles and deliver helper signals to B cells, and thus play a critical role in functional maturation of a humoral immune response. Global analysis of gene expression has shown that both germinal center B cells and TFH have unique patterns of gene expression that distinguish them from other subsets of naive and activated lymphocytes. One of the genes reported to be expressed specifically in both germinal center B cells and TFH encodes TOX, a protein highly conserved between rodents and humans and first identified in our laboratory as a regulator of T cell development. We have produced TOX transgenic mice and globally and conditionally TOX-deficient mice and have shown that TOX is required for development of the CD4 T cell lineage. Using combinations of these genetically modified animals, we propose here to determine whether TOX also plays a role in germinal center reactions. Our approaches allow us to distinguish the effects of TOX-deficiency on B and T cells. Thus, breeding conditionally TOX-deficient mice to mice that express Cre recombinase in the B cell lineage will be used to look for defects in germinal center B cell formation and function upon immunization. Two complementary approaches are proposed to study similarly the role of TOX in TFH development and function; complementation of globally TOX-deficient mice with a thymically expressed TOX transgene and in vitro Cre-mediated deletion of the Tox locus in CD4+ T cells that are subsequently tested for TFH development and function in vivo. To complement these studies we also propose to generate a TOX reporter knock-in strain of mice that will allow us to track expression of TOX in viable cells and in vivo during an immune response. PUBLIC HEALTH RELEVANCE: A protective antibody-mediated immune response requires T and B lymphocyte interactions in specialized areas of secondary lymphoid tissue known as germinal centers. Understanding the regulation of these interactions is important for vaccine development and for understanding the role of germinal center lymphocytes in tumor development and autoimmunity. This research program is directed at understanding the role of a specific nuclear protein, highly conserved in rodents and humans, in regulating these germinal center reactions.