GENETIC COMPLEXITY OF HLA CLASS II GENE REGULATION

人类主要组织相容性复合体II类基因的调控 在这项提案中，表达是调查的主要重点。Hla II类抗原是一类多态的表面糖蛋白。 主要表达于B淋巴细胞、巨噬细胞和活化的T细胞。 这些抗原是识别外来或改变的抗原所必需的 由免疫系统产生的物质。因此，对这些问题的监管研究 基因对于理解控制免疫的机制很重要。 反应，更广泛地说，那些控制真核基因的反应 表情。 拟议中的实验是先前工作的延续 人类白细胞抗原B细胞系表达缺陷的特征 II类阴性先天性免疫缺陷(以前为裸淋巴细胞 综合征，BLS)患者。一种使用插入突变的策略 概述了产生新的人类白细胞抗原II类阴性突变体的逆转录病毒。 这种方法的目标是从亲本衍生的细胞系。 在BLS患者中。因为家庭研究和早期对此的分析 实验室表明BLS是一种常染色体隐性缺陷，它是 假设亲本细胞只包含一个完整的和正常的 特定调控基因的拷贝。因此，整合一个前病毒 野生型调控基因内或附近基因组应该影响其 表达和/或功能，导致较低或不存在II级 允许选择突变细胞的表达。联动 前病毒到假定的调控基因将允许分离 基因组序列。随后，这些侧翼区域内的外显子 鉴定并用于分离cdna克隆。特征化和 这些克隆的表达可以揭示其功能的线索。 这些调控基因。 除了促进对基本监管机制的了解外 在免疫应答中，识别突变的调控基因 应该为BLS患者带来基因治疗和长期受益。 可能更重要的是对调控基因的分析 自身免疫性疾病中人类白细胞抗原异常表达的研究 第二类基因经常被发现。此外，人类白细胞抗原II类分子的激活 在许多人类恶性肿瘤中的表达可能是通过调控 我们定义的基因可能是肿瘤进展的一个重要因素。 了解人类白细胞抗原II类调控基因的结构和功能 应该提供新的策略来改变人类白细胞抗原II类的表达和 影响疾病的发展。

Regulation of HLA (human major histocompatibility complex) class II gene expression is the primary focus of investigation in this proposal. HLA Class II antigens are a family of polymorphic surface glycoproteins expressed primarily on B lymphocytes, macrophages, and activated T cells. These antigens are required for the recognition of foreign or altered substances by the immune system. Thus, study of the regulation of these genes is important in understanding the mechanisms that control an immune response and more generally, those that control eukaryotic gene expression. The proposed experiments are a continuation of previous work characterizing defective expression in B cell lines derived from HLA Class II negative congenital immunodeficiency (formerly Bare Lymphocyte Syndrome, BLS) patients. A strategy using insertional mutagenesis with retroviruses to generate new HLA class II negative mutants is outlined. The targets in this approach will be cell lines derived from the parents of BLS patients. Because family studies and earlier analyses from this laboratory indicate that BLS is an autosomal recessive defect, it is assumed that the parental cells contain only one intact and functional copy of a particular regulatory gene. Thus, integration of a proviral genome within or near that wild type regulatory gene should affect its expression and/or function, resulting in lower or absent class II expression allowing selection of the mutant cells. Linkage of the provirus to the putative regulatory gene will allow the isolation of genomic sequences. Subsequently, exons within these flanking regions identified and used to isolate cDNA clones. Characterization and expression of the cDNA clones should reveal clues to the function of these regulatory genes. In addition to promoting the understanding of basic regulatory mechanisms in the immune response, the identification of mutant regulatory genes should lead to gene therapy and long term benefit for BLS patients. Potentially even more important, will be an analysis of regulatory genes in patients with autoimmune diseases in which aberrant expression of HLA class II genes is often found. Furthermore, activation of HLA class II expression in many human malignancies perhaps through the regulatory genes we define may be a significant factor in tumor progression. Understanding the structure and function of HLA class II regulatory genes should provide new strategies to alter HLA class II expression and influence the development of disease.