Neutrophil phenotyping in periodic and chronic arthritis

关节内中性粒细胞的迁移和活化可能在炎性关节炎的关节侵蚀中起主要作用。DNA微阵列提供了一种方法来分析关节炎患者炎症关节中性粒细胞的基因表达。基因图谱可以识别关节内炎症的中性粒细胞调节因子，并确定炎性关节炎之间的关键相似性和差异性。家族性地中海热（FMF）患者的关节炎是由MEFV突变引起的，MEFV是一种编码在骨髓细胞中特异性表达的炎症调节因子的基因。FMF关节炎是不寻常的，因为大多数炎性细胞是中性粒细胞，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。提出了三个具体的目标：首先，我们将使用免疫组化和ELISA来定义关节内白细胞浸润和细胞因子在FMF关节炎的性质。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，我们将从收集的中性粒细胞的RNA样品进行微阵列分析，这些中性粒细胞来自患有周期性关节炎（FMF）、慢性（类风湿性和银屑病）、反应性和感染性关节炎的患者的活动关节和外周血，以及来自对照组的外周血中性粒细胞。将分析差异表达的基因，特别注意识别炎症调节因子和定义特定疾病中的亚表型。第三，我们将测试特定中性粒细胞基因产物在调节白细胞粘附和信号传导中的功能。进行MEFV基因以确定pyrin是否将在骨髓细胞系中表达，并且来自细胞的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物，将在白细胞粘附、跨内皮迁移、趋化性和其他功能的测定中进行测试。这些研究将定义关节内中性粒细胞迁移和激活的介质，并可能提供对其他形式炎症中调节白细胞募集机制的见解。

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.