HLA-DP SEQUENCE POLYMORPHISM AND DISEASE PREDISPOSITION

我们的目标是了解HLA-DP区域多态性的功能意义和进化及其与疾病易感性的关系。其他HLA II类位点，DRB1和DQB1的多态性在一段时间内被认为与多种疾病的易感性有关。DPB1位点广泛多态性（迄今已确定的bbbb80等位基因）在疾病易感性中的作用尚不清楚。我们的假设是，多个HLA位点的特定等位基因组合决定了对特定疾病的易感性程度。我们将集中在三种疾病：少关节幼年类风湿性关节炎，1型糖尿病和宫颈癌。这些疾病似乎与DPB1相关，也与DRB1和/或DQB1位点的特定等位基因相关。我们针对II类和I类基因座的高分辨率固定探针分型方法将应用于来自各种人群的患者和对照样本。基于家族的材料可以分析单倍型共享、传输率和连锁不平衡模式，以及分层分析，以确定DPB1或任何其他HLA位点的相关等位基因是否会增加风险，或者仅仅反映与其他HLA位点的高风险等位基因的连锁不平衡。研究HLA等位基因多样性是如何进化的，以及它是如何在不同人群中分布的，可以提供对功能意义的见解。我们将利用基于pcr的方法测量精子中罕见变异DPB1序列的频率，并通过对人类和非人类灵长类动物的外显子2和邻近内含子序列的系统发育分析来分析DPB1多样性的进化，从而验证DPB1和其他HLA位点的拼凑型多态性模式反映基因转换（片段交换）操作的假设。HLA疾病关联反映了CD4+T细胞特异性抗原刺激后促进Th1和Th2反应的差异倾向，这一假设将通过定量动力学PCR来监测细胞因子的表达。该方法将应用于hpv感染的宫颈样本和GAD肽刺激的体外系统，以研究HLA与宫颈癌和1型糖尿病的关系。

Our goal is to understand the functional significance and evolution of the polymorphism at the HLA-DP region and its relationship to disease susceptibility. Polymorphism at other HLA class II loci, DRB1 and DQB1 has been implicated for some time in predisposition to a variety of diseases. The role of the extensive polymorphism at the DPB1 locus (>80 alleles identified thus far) in disease predisposition is much less well understood. It is our hypothesis that specific combinations of alleles at multiple HLA loci determine the extent of susceptibility to a given disease. We will focus on three diseases: pauciarticular juvenile rheumatoid arthritis, type 1 diabetes, and cervical carcinoma. These diseases appear to have DPB1 associations as well as associations with specific alleles at the DRB1 and/or DQB1 locus. Our high resolution immobilized probe typing methods for the class II and class I loci will be applied to patient and control samples from a variety of populations. Family based material allows the analysis of haplotype sharing, transmission ratios, and linkage disequilibrium patterns as well as stratification analysis to see whether some of the associated alleles at DPB1, or any other individual HLA locus, confer increased risk or simply reflect linkage disequilibrium with high risk alleles at other HLA loci. Studying how HLA allelic diversity has evolved and how it is distributed in various human populations can provide insights into functional significance. The hypothesis that the patchwork patterns of polymorphism at the DPB1 and at other HLA loci reflects the operation of gene conversion (segmental exchange) will be tested by using a PCR-based method to measure the frequency of rare variant DPB1 sequences in sperm and the evolution of DPB1 diversity will be analyzed via phylogenetic analysis of exon2 and adjacent intron sequences from human and non- human primates. The hypothesis that HLA disease associations reflect the differential tendency to promote Th1 and Th2 responses following specific antigen stimulation of CD4+T cells will be examined using quantitative kinetic PCR to monitor cytokine expression. This method will be applied to HPV-infected cervical samples and an in vitro system with GAD peptide stimulation to study the HLA associations with cervical cancer and type 1 diabetes.