Research of the pathogenesis of arthritis rheumatoid by micro RNA and msearch of the possibility of a novel diagnosis method for arthritis rheumatoid by micro RNA

类风湿关节炎（RA）是一种病因不明的慢性疾病，表现出一系列特征，包括白细胞浸润滑膜细胞和滑膜细胞增生，导致滑膜形成和关节破坏。这些细胞局部产生细胞因子和趋化因子是许多RA病理和临床表现的原因。目前尚不存在能够诊断早期RA或预测当前治疗反应的分子标志物。我们的目的是通过分析一种新的RNA干扰因子——微RNA （miRNA）的表达来揭示RA的发病机制，并探索发明一种新的诊断方法和治疗方法的可能性。研究重点之一是识别RA成纤维细胞样滑膜细胞（RA- fis）的特异性mirna。我们发现有5种miRNA在RA-FLS中比骨关节炎FIS （0A-FLS）表达更强烈，miR-124a是RA-FLS中唯一与OA-FLS相比显著降低的miRNA。将miR-124a前体转染到RA-FLS中，可显著抑制RA-FLS的增殖，迫使细胞周期停止在G1期，但RA-FLS的凋亡未明显增加。我们在CDK2和MCP1 mRNA的3UTR区域发现了一个公认的miR-124a结合位点，并且诱导miR-124a进入RA-FLS显著抑制了CDK2和MCP1蛋白的产生。这些结果表明，RA- fls中miR-124a表达的降低与RA的发病机制密切相关。另一个研究重点是在外周血单核细胞（PBMC）中鉴定ra特异性mirna。我们一直在寻找PBMC中ra特异性的miRNA，初步数据显示，预计会出现与RA-FLS完全不同的miRNA。所有研究费用用于购买化学试剂和一次性设备。

Rheumatoid arthritis (RA) is a chronic disease of unknown etiology that presents a characteristic constellation of features that includes infiltrating leukocytes to synoviocytes and synoviocyte hyperplasia, resulting in pannus formation and joint destruction. The local production of cytokines and chemokines by these cells accounts for many of the pathological and clinical manifestations of RA. The molecular marker which could diagnose early RA or predict the response to currently used treatments does not exist.Our aim was to reveal the pathogenesis of RA by analyzing the expression of micro RNA (miRNA), a novel RNA interfence factor, and to exploit the possibility of inventing a novel diagnostic method and a novel therapy.One of the research foci was the identification of the specific miRNAs to RA fibroblast-like synoviocyte (RA-FIS). We found that five miRNAs were more strongly expressed in RA-FLS than in osteoarthritis FIS (0A-FLS), and miR-124a was the only significantly decreased miRNA in RA-FLS as compared to OA-FLS. The transfection of a precursor of miR-124a into RA-FLS suppressed their proliferation significantly and forced to stop the cell cycle at G1 phase with no significant increase of apoptosis to RA-FLS. We identified a putative consensus site for miR-124a binding in the 3UTR regions of CDK2 and MCP1 mRNA, and induction of miR-124a into RA-FLS significantly suppressed the production of CDK2 and MCP1 proteins. These results suggest that decreasing miR-124a expression in RA-FLS is deeply involved in the pathogenesis of RA.Another research focus was to identify the RA-specific miRNAs in peripheral blood mononuclear cells (PBMC). We have been searching for RA-specific miRNA in PBMC, and preliminary data show that totally different sets of miRNAs from that of RA-FLS are anticipated.All research expenses were spent to buy chemical reagents and disposable equipments.