HIGMX 1--TRANSGENIC MODELS OF CD40L DEFICIENCY

原发性免疫缺陷疾病提供了独特的研究机会 离散细胞和分子在免疫反应中的作用。 我们 总体目标是了解CD40及其配体在免疫中的作用， 通过对病人和基因工程小鼠的研究， CD40和CD40缺乏症。 CD 40在B细胞、胸腺上皮和树突细胞上表达， 在B细胞存活、活化、分化中起重要作用 和阶级转换。 表达CD40配体（CD40 L/gp39） 以发育调节的方式专门作用于活化的T细胞。 我们最近发现，CD40 L基因突变导致 CD40L的功能或表达是X连锁的基础。 高IgM综合征（HIGMX-1）。 CD40的缺乏还没有被发现。 介绍了 在目的1中，我们建议详细分析CD40 L的机制， 缺乏HighMX-1。 我们将描述CD40L基因的缺陷， 在一组HIGMX-1患者中，在cDNA水平和基因组水平， 水平 后者需要分析基因组组织， 人类CD40L基因的最小转录单位。 在目的2中，我们建议构建小鼠模型的HIGMX-1，以获得一个新的模型。 更好地了解CD40 L缺乏症，并开始测试新的 HIGMX-1的治疗方式。 为此，我们将 通过RAG-2缺陷型胚泡互补的CD40L缺陷型小鼠， 通过破坏CD40L生殖系基因。 我们还将建立 在CD40L中具有离散突变的转基因小鼠以模拟突变 以确定CD40L结构域的功能。 在目标3中，我们将研究CD40在免疫系统发展中的作用。 细胞，并通过研究确定CD40缺乏的表型， CD$0敲除小鼠。 CD 40在B细胞发育和功能中的作用 将通过检查由RAG-2构建的CD40缺陷小鼠来定义 胚泡互补不足。 CD40在肿瘤中的作用 胸腺上皮细胞和树突状细胞的发育和功能 将在具有破坏的CD40L生殖系基因的小鼠中进行分析。

Primary immunodeficiency diseases provide unique opportunities to study the role of discrete cells and molecules in the immune response. Our general aim is to understand the role of CD40 and of its ligand in immune function through the study of patients and of genetically engineered mice with CD40l and CD40 deficiency. CD40 is expressed on B cells, thymic epithelium and dendritic cells and plays an important role in B cell survival, activation, differentiation and class switching. The ligand for CD40 (CD40L/gp39) is expressed exclusively on activated T cells in a developmentally regulated manner. We have recently found that mutations in the CD40L gene resulting in loss of function or expression of CD40L are the basis for the X-linked HyperIgM syndrome(HIGMX-1). Deficiency in CD40 has not yet been described. In Aim 1, we propose to analyze in detail the mechanisms of CD40L deficiency in HIGMX-1. We will characterize the defect in the CD40L gene in a panel of HIGMX-1 patients at the cDNA level and at the genomic level. The latter requires an analysis of the genomic organization and of the minimal transcriptional unit of the human CD40L gene. In Aim 2, we propose to construct a murine model of HIGMX-1 to gain a better understanding of CD40L deficiency and to begin testing novel therapeutic modalities for HIGMX-1. To this purpose, we will generate CD40L deficient mice by RAG-2-deficient blastocyst complementation and by disruption of the CD40L germline gene. We will also construct transgenic mice with discrete mutations in CD40L to mimic the mutations in HIGMX-1 patients and to define the function of CD40L domains. In Aim 3, we will examine the role of CD40 in the development of immune cells and define the phenotype of CD40 deficiency through the study of CD$0 knockout mice. The role of CD40 in B cell development and function will be defined by examining CD40 deficient mice constructed by RAG-2 deficient blastocyst complementation. The role of CD40 in the development and function of thymic epithelial cells and dendritic cells will be analyzed in mice with disrupted CD40L germline gene.