强直性脊柱炎易感基因ERAP1的精细作图及致病机制的研究

Ankylosing spondylitis (AS) is a common cause of inflammatory arthritis with an approximate prevalence of 3 per 1000 in Chinese population. AS is highly heritable and has now been convincingly associated with several non-B27 genes (loci containing the genes IL23R, ERAP1 and KIF21B and the 2p15 and 21q22 intergenic regions), among which ERAP1 has been confirmed to be most strongly associated with AS. In our previous studies, we successfully identified HLA-B*2704 as the predominant subtype of HLA-B27 that is strongly associated with AS in Chinese Han patients, and for the first time in the world confirmed a non-MHC gene (ERAP1) in AS in a nonwhite European population. However, up to now, no fine-mapping for ERAP1 has been done to identify the directly causative SNP of ERAP1 to AS, meanwhile the precise role of ERAP1 in the pathogenesis of AS is unknown. Therefore, we intend to perform a study aiming to identify the causative SNP of ERAP1 to AS by using the high-throughput next-generation sequencing. Besides, we plan to investigate the potential correlation between variants of ERAP1 and the HLA-B27 subtypes. Furthermore, we will study the influence of different variants of ERAP1 on the function of CD39+Treg cells. This study is expected to demonstrate the potential role of ERAP1 in the pathogenesis of AS.

强直性脊柱炎（AS）是最常见的炎症性关节炎之一，在我国患病率高达0.3％，其发病有很强的遗传学背景。众多研究发现非HLA-B27基因参与AS的发病，其中以ERAP1基因与AS发病相关性最强。我们前期研究发现与汉族人AS有很强关联性的HLA-B27亚型（B*2704），并率先在国内证实ERAP1与汉族人AS的相关性。但是，迄今尚无研究对ERAP1进行进一步的精细作图（fine-mapping），即鉴定出ERAP1中与AS发病直接相关的变异位点（致病性SNP），且未明确ERAP1在AS发病中的确切作用。本项目拟对汉族人AS患者和健康对照的ERAP1重点区域进行高通量第二代测序，以准确定位ERAP1中的致病性SNP；同时研究HLA-B27亚型和ERAP1不同变异体之间潜在的关联性；再对CD39+Treg细胞功能与ERAP1的多态性进行关联研究，从功能学层面揭示ERAP1在AS发病中的确切作用。

强直性脊柱炎（AS）发病有很强的遗传学背景，HLA-B27基因和ERAP1基因与AS发病相关性最强。本项目旨在准确定位ERAP1中的致病性SNP，同时研究HLA-B27亚型和ERAP1不同变异体之间潜在的关联性，从功能学层面揭示ERAP1在AS发病中的确切作用。. 项目组成功建立了自然表达与AS相关HLA-B27亚型的人B淋巴母细胞，并用CRISPR/Cas9系统成功敲除B淋巴母细胞ERAP基因，获得了不同种系的BCL，继而又对AS患者的ERAP mRNA进行测序，探讨了ERAP基因变异对HLA-B27递呈的抗原肽谱的影响。此外，项目组还自主开发了一个新型临床数据分析平台，自动化采集录入真实世界AS患者的临床数据，并进行了精确的数据分析。项目组所构建的实验体系为后续进一步研究ERAP和B27的基因交互作用，以及ERAP1和HLA-B27亚型与AS临床表现之间的遗传学关联奠定了基础。. 研究期间在国际会议上交流论文1次（分会发言），以第2完成人身份获上海医学科技奖一等奖1次，举办和承办国际学术会议各1次，承办国内学术会议1次，协助培养硕士研究生1名。