SELECTIVE EXPRESSION OF LYMPHOKINES IN T LYMPHOCYTES

CD4+T细胞对淋巴因子的差异表达起着关键作用 对免疫反应进行适当的调节。因此，异常的 淋巴因子表达的控制可以对 结核病和艾滋病毒等多种传染病的进展 以及糖尿病和多发性硬化症等自身免疫性疾病。 分泌干扰素-γ、白介素2和淋巴毒素的Th1细胞直接 迟发性超敏反应在防御中很重要 对抗细胞内的生物。产生IL-4的Th2细胞直接 过敏或抗炎反应和防止蠕虫 感染。干扰素-γ、白介素2和白介素4的调节主要发生在 基因转录的水平，但选择性的基础 不同T细胞亚群对这些淋巴因子的表达 不清楚。这项提案的总体目标是定义 干扰素-γ和白介素4差异的分子机制 Th1/Th2 CD4+T细胞的调节及动物模型的建立 其中发展极化细胞的生物学重要性 T细胞群对感染和自身免疫性疾病的反应 可以被评估。我们最近的研究已经定义了一个关键的监管 干扰素-γ启动子中可能参与选择性 干扰素-γ在Th1细胞中的表达及在Th2细胞中的缺失 细胞通过与可调节和抑制的因子相互作用 表达和甲基化。此提案的目标是使用 检验这一假设的方法有两种。第一种方法将 利用含有该元件的构建体的瞬时转基因 转化为Th1和Th2细胞，剖析其所涉及的分子途径。这个 第二种伴随方法将利用体内启动子交换 旨在确定这一点的生理重要性的实验 元素在内源基因的背景下并解决其作用 甲基化。这些研究将建立在候选人之前 培训，并使她能够在 转基因动物的产生和评估以及对 在整个动物环境中免疫反应的复杂性。这些 技能对于她成为一个独立的人是必不可少的 调查员。赞助商的实验室提供了理想的环境 从小鼠胚胎开始进行拟议的实验 这个组织和其他人成功地利用了操纵 所有分析老鼠所需的工具都是 可用。

Differential expression of lymphokines by CD4+ T cells plays a key role in proper modulation of the immune response. Consequently, aberrant control of lymphokine expression can have wide ranging impact on the progression of many infectious diseases such as tuberculosis and HIV as well as autoimmune diseases such as diabetes and multiple sclerosis. Th1 cells, which secrete IFN-gamma, IL-2 and lymphotoxin, direct delayed type hypersensitivity responses and are important in defense against intracellular organisms. Th2 cells, which produce IL-4, direct allergic or anti-inflammatory responses and protect against helminth infections. Regulation of IFN-gamma, IL-2 and IL-4 occurs primarily at the level of gene transcription, but the basis for the selective expression of these lymphokines by the various T cell subsets remains unclear. The overall objectives of this proposal are to define the molecular mechanisms by which IFN-gamma and IL-4 are differentially regulated by Th1 and Th2 CD4+ T cells and to develop an animal model in which the biological importance of developing the polarized population of T cells in response to infection and autoimmune disease can be assessed. Our recent studies have defined a key regulatory element in the IFN-gamma promoter which may contribute to the selective expression of IFN-gamma in Th1 cells and lack of expression in Th2 cells via interaction with factors which can mediate and repress expression and by methylation. The goal of this proposal is to use a two pronged approach to test this hypothesis. The first approach will utilize transient transfection of constructs containing this element into Th1 and Th2 cells to dissect the molecular pathway involved. The second concomitant approach will utilize in vivo promoter swapping experiments designed to determine the physiological importance of this element in the context of the endogenous gene and to address the role of methylation. These studies will build upon the candidate's previous training and allow her to gain significant new expertise in the generation and assessment of transgenic animals and in analysis of the complexity of the immune response in a whole animal context. These skills are essential for her development into an independent investigator. The sponsor's laboratory provides an ideal environment in which to pursue the proposed experiments since mouse embryo manipulation has been successfully utilized by this group and others at this institution and all the tools necessary to analyze the mice are available.