Neutrophil phenotyping in periodic and chronic arthritis

中性粒细胞在关节内的迁移和激活可能在炎性关节炎的关节侵蚀中起主要作用。DNA微阵列提供了一种分析关节炎患者炎症关节中性粒细胞基因表达的方法。基因图谱可以确定关节内炎症的中性粒细胞调节因子，并确定炎症性关节炎之间的关键异同。家族性地中海热(FMF)患者的关节炎是由MEFV突变引起的，MEFV是一种编码炎症调节因子的基因，在髓系细胞中特异表达。FMF关节炎的不同寻常之处在于，大多数炎症细胞是中性粒细胞，而且关节炎的发作是短暂的。因此，它代表了一种独特的人类模型，将滑膜炎的起始阶段与慢性阶段分开。我们提出了三个具体目标：首先，我们将使用免疫组织化学和ELISA来确定FMF关节炎中关节内白细胞浸润的性质和细胞因子谱。这些数据将与其他形式的关节炎的已知特征进行比较。其次，我们将从活动期(FMF)、慢性(类风湿性和牛皮癣)、反应性和感染性关节炎患者的活动期关节和外周血液中收集中性粒细胞RNA样本，并从对照组的外周血中性粒细胞中收集RNA样本进行微阵列分析。将分析差异表达的基因，特别注意识别炎症的调节因素和确定特定疾病的亚型。第三，我们将测试特定的中性粒细胞基因产物在调节白细胞黏附和信号转导方面的功能。MEFV基因用于确定是否将在髓系细胞系中表达派林素，以及对来自细胞的RNA的微阵列分析将在FMF或其他形式的关节炎中差异表达已知或新的基因产品，将在白细胞黏附、跨内皮细胞迁移、趋化和其他功能的分析中进行测试。这些研究将确定中性粒细胞在关节内迁移和激活的介质，并可能为调节其他形式的炎症中白细胞募集的机制提供见解。

Intra-articular migration and activation of neutrophils may play a principal role in the joint erosion of inflammatory arthritis. DNA microarrays provide a means to profile gene expression in neutrophils from inflamed joints of patients with arthritis. Gene profiling may identify neutrophil regulators of intra-articular inflammation, and define key similarities and differences among inflammatory arthridities. The arthritis in patients with familial Mediterranean fever (FMF) is caused by mutations in MEFV, a gene encoding an inflammatory regulator that is specifically expressed in myeloid cells. FMF arthritis is unusual in that most inflammatory cells are neutrophils, and episodes of arthritis are transient. It therefore represents a unique human model to uncouple the initiation phase of synovitis from the chronic phase. Three specific aims are proposed: First, we will use immunohistochemistry and ELISAs to define the nature of intra-articular leukocyte infiltrates and cytokine profiles in FMF arthritis. These data will be compared with known profiles in other forms of arthritis. Second, we will perform microarray analysis from collected RNA samples of neutrophils form the active joints and peripheral blood of patients with period (FMF), chronic (rheumatoid and psoriatic), reactive, and infectious arthritis and from peripheral blood neutrophils of controls. Differentially expressed genes will be analyzed, with particular attention to identifying regulators of inflammation and defining subphenotypes within a specific disease. Third, we will test the functions of specific neutrophil gene products in modulating leukocyte adhesion and signaling. The MEFV gene performed to determine whether pyrin, will be expressed in myeloid cell lines, and microarray analysis of RNA from the cells will be differentially expressed known or novel gene products in FMF or other forms of arthritis will be tested in assays of leukocyte adhesion, transendothelial migration, chemotaxis, and other functions. These studies will define mediators of intra-articular neutrophil migration and activation, and may provide insights into the mechanisms that regulate leukocyte recruitment in other forms of inflammation.