Regulation of Il-4 in Cells Involved in Allergic Disease

描述(申请人提供)：IL-4在Th2细胞和嗜碱性粒细胞中表达。IL-4的高表达是过敏性疾病的一个公认的标志。最近的研究发现，核因子的表达或激活与Th2限制的IL-4表达有关。我们已经鉴定出两种对IL-4和IL-2转录有不同影响的核因子，即CP2和NF-kappaB。我们发现CP2和核因子-kappaB基因p65和p50在Th1和Th2细胞中有差异表达，并通过与其他核因子的复杂相互作用直接与IL-4启动子相互作用来调节转录。我们推测这些蛋白在IL-4基因的激活中起着相关的作用。我们将研究：1)CP2在IL-4基因激活中的作用(目标1)。我们将分析CP2在Th细胞和嗜碱性粒细胞中的表达和功能，以及CP2耗竭、功能障碍或强迫表达对IL-4产生的影响。2)核因子-kappaB分子物种对IL-4调节的意义(目标2)。我们的发现暗示p65-p50平衡直接影响Th细胞和嗜碱性粒细胞中IL-4的表达。我们将观察p65在这些细胞中的表达，以及选择性阻断p65对转跨显性抑制基因小鼠细胞因子诱导的影响。3)CP2和p50激活IL-4基因的机制(目标3)。通过体外和体内蛋白质-DNA相互作用的分析，我们将研究CP2和p50与IL-4启动子和远端调控元件的功能相互作用及其对IL-4位点重塑和可及性的影响。我们将研究它们与辅助因子阴阳1、Bcl-3和NF-IL6相互作用的意义。剖析IL-4的调节机制对于了解变态反应性疾病的分子基础具有重要意义。该方法通过确定CP2和NF-kappaB在IL-4转录中的作用，将为研究这些因子在变态反应性炎症中的表达和功能提供基础，并为免疫调节寻找新的、特异的分子靶点。鉴于CP2和NF-kappaB参与了多种细胞和病毒基因的转录，我们的结果也将对定义这些蛋白质在健康和疾病中基因表达调控的意义和功能具有更广泛的意义。

DESCRIPTION (provided by applicant): IL-4 is expressed in Th2 cells and basophils. Increased expression of IL-4 is an established hallmark of allergic diseases. Recent studies have allowed the identification of nuclear factors (NF) whose expression or activation are associated with Th2-restricted expression of IL-4. We have identified two NF, CP2 and NF-kappaB, exerting diverging effects on IL-4 and IL-2 transcription. We show that CP2 and the NF-kappaB species p65 and p50 are differentially expressed in Th1 and Th2 cells and regulate transcription by directly interacting with the IL-4 promoter via a complex interplay with other NF. We hypothesize that these proteins play a relevant role in activation of the IL-4 gene. We will investigate: 1) The role of CP2 in IL-4 gene activation (Aim 1). We will analyze the expression and function of CP2 in Th cells and basophils and the effect of CP2 depletion, functional impairment or forced expression on IL-4 production. 2) The significance of IL-4 regulation by NF-kappaB molecular species (Aim 2). Our findings implicate that the p65-p50 balance directly affects IL-4 expression in Th cells and basophils. We will look at the expression of p65 in these cells, and the impact of selective p65 blockade on cytokine induction in mice transgenic for a transdominant repressor. 3) The mechanism of IL-4 gene activation by CP2 and p50 (Aim 3). By in vitro and in vivo analysis of protein-DNA interactions we will study the functional interaction of CP2 and p50 with the IL-4 promoter and distal regulatory elements and their impact on IL-4locus remodeling and accessibility. We will study the significance of their interaction with the cofactors Yin Yang 1, Bcl-3 and NF-IL6. Dissecting the mechanisms of IL-4 regulation is of crucial importance to understanding the molecular basis of allergic disease. The proposed approach, by defining the roles ofCP2 and NF-kappaB in IL-4 transcription, will provide a basis for studies of the expression and function of these factors in allergic inflammation, and identify novel, specific molecular targets for immunomodulation. Given the involvement of CP2 and NF-kappaB in transcription of a diverse host of cellular and viral genes, our results will also have broader implications in the definition of the significance and function of these proteins in the regulation of gene expression in health and disease.