SELECTINS AND CARBOHYDRATES IN CELL ADHESION AND ARTHRITIS

类风湿关节炎(RA)是一种慢性、进行性、破坏性的关节 这种疾病会导致极大的发病率和超额死亡率。组织学 RA滑膜评估显示明显的血源性浸润物 白细胞；这些细胞的激活维持炎症反应 这会导致RA的关节损伤。炎症中的白细胞聚集 病灶是一个多方面的过程，从细胞黏附到 微血管内皮细胞这一关键过程是相互作用的结果 内皮分子和白细胞表面分子之间的关系，包括 选择素基因家族。我们实验室最近的工作确定了 E-选择素的配体作为碳水化合物，唾液酸化形式的 Lewis x血型相关分子(SLeX)。 这一提议的基本假设是：(1)白细胞 RA关节中的积聚是由选择素的选择性表达诱导的， (2)抑制选择素与配体的结合会抑制白细胞 积聚，防止接缝损坏。为了检验这些假说，滑膜 来自类风湿关节炎患者和两个具有良好特征的类风湿关节炎动物模型 (兔膝关节卵白蛋白诱导的关节炎和链球菌细胞壁 大鼠的关节炎)将被使用。 研究计划的一个基本前提是产生 克隆的cDNAs、重组蛋白和中和抗体 在兔、大鼠和人类组织中进行研究的选择素。第一 实验目标将是准备和验证这些活动 试剂，通过评估选择素在体外黏附模型中的表达 使用来自每个测试物种的细胞。一种在体外很好地表征了 白细胞与内皮细胞的黏附试验将被用来检测 中和抗体、SLeX等的抑制活性 碳水化合物类似物，以及重组选择素分子。 下一个实验目标将是定位选择蛋白的表达 在关节炎关节中，通过免疫组织化学方法，并评估 特定白细胞类型聚集部位的对应关系 局部表达选择素及其配体。 该项目的最后一个组成部分将决定管理 可溶性形式的选择素配体、中和抗体或 重组选择素可抑制关节炎的发展。这些研究 将描述选择素分子对发展的贡献 关节炎病变，为临床治疗提供科学依据。 基于这些分子的类风湿关节炎新的治疗干预措施 互动。

Rheumatoid arthritis (RA) is a chronic, progressive, destructive joint disease which causes immense morbidity and excess mortality. Histological assessment of RA synovium reveals prominent infiltrates of blood-derived leukocytes; activation of these cells sustains the inflammatory response which leads to joint injury in RA. Leukocyte accumulation in inflammatory foci is a multi-faceted process that begins with cell adhesion to microvascular endothelium. This crucial process results from interactions between endothelial and leukocyte surface molecules, including members of the Selectin gene family. Recent work from our laboratory has identified the ligand for E-Selectin as a carbohydrate, the sialylated form of the Lewis x blood group related molecule (sLex). The underlying hypotheses of this proposal are that: (1) leukocyte accumulation in RA joints is induced by selective expression of Selectins, and (2) inhibition of Selectin-ligand binding will suppress leukocyte accumulation and prevent joint damage. To test these hypotheses, synovium from patients with RA and from two well-characterized animal models of RA (ovalbumin-induced arthritis in the rabbit knee and streptococcal cell wall arthritis in the rat) will be used. An essential prerequisite for the research program will be to generate cloned cDNA's, recombinant proteins, and neutralizing antibodies to Selectins to perform studies in rabbit, rat, and human tissue. The first experimental goal will be to prepare and validate the activity of these reagents, by assessing Selectin expression in in vitro adhesion models using cells derived from each test species. A well-characterized in vitro assay of leukocyte adhesion to endothelium will be used to test the inhibitory activity of the neutralizing antibodies, sLex and other carbohydrate analogs, and the recombinant Selectin molecules. The next experimental goal will be to localize Selectin protein expression in the arthritic joint, by immunohistochemistry, and to assess the correspondence of the sites of specific leukocyte cell-type accumulation with local expression of Selectins and their ligands. The final component of this project will determine whether administration of soluble forms of Selectin ligands, neutralizing antibodies, or recombinant Selectins inhibits the development of arthritis. These studies will delineate the contribution of Selectin molecules to the development of the arthritic lesion, and they may provide the scientific foundation for novel therapeutic interventions for RA, based on these molecular interactions.