HLA-DP SEQUENCE POLYMORPHISM AND DISEASE PREDISPOSITION

我们的目标是了解人类白细胞抗原-DP基因多态的功能意义和进化，以及它与疾病易感性的关系。其他HLAII类基因座DRB1和DQB1的多态性与多种疾病的易感性有关已经有一段时间了。DPB1基因(迄今已发现的80个等位基因)的广泛多态在疾病易感性中的作用还不是很清楚。我们的假设是，多个人类白细胞抗原基因座的特定等位基因组合决定了对特定疾病的易感性程度。我们将关注三种疾病：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，并与DRB1和/或DQB1基因座上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化探针分型方法将应用于来自不同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、传播率和连锁不平衡模式，以及分层分析，以了解DPB1或任何其他单个HLA基因座的一些相关等位基因是否增加了风险，或者只是反映了与其他HL A基因座的高危等位基因的连锁不平衡。研究人类白细胞抗原等位基因多样性是如何进化的，以及它是如何在不同的人类群体中分布的，可以提供对功能意义的洞察。DPB1和其他基因座的多态拼接模式反映了基因转换(片段交换)的操作，这一假设将通过基于PCR的方法来测试精子中罕见变异DPB1序列的频率，并将通过对人类和非人类灵长类动物的外显子2和相邻内含子序列的系统发育分析来分析DPB1多样性的进化。我们将使用定量动力学聚合酶链式反应来监测细胞因子的表达，以检验这一假设，即人类白细胞抗原疾病相关性反映了在CD4+T细胞的特异性抗原刺激后促进Th1和Th2反应的不同趋势。该方法将应用于HPV感染的宫颈样本和GAD多肽刺激的体外系统，以研究人类白细胞抗原与宫颈癌和1型糖尿病的相关性。

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.