UNIQUE ENDOTHELIAL MOLECULES IN AUTOIMMUNE INFLAMMATION

自身反应性和效应性淋巴细胞从血液到靶器官的迁移是自身免疫性疾病靶器官损伤的始发和维持过程中的关键事件。这种迁移涉及一个复杂的黏附级联反应，伴随着一系列淋巴细胞/内皮细胞黏附和激活事件。我们的目标是确定高内皮微静脉(HEV)在自身免疫介导的炎症和组织破坏部位表达的黏附触发趋化因子和新的激活和黏附分子，并确定这些分子在淋巴细胞向这些部位迁移中的作用。我们将使用非肥胖糖尿病(NOD)小鼠作为模型，以确定参与淋巴细胞迁移到炎症的胰岛、唾液腺和泪腺的独特内皮分子。NOD小鼠是人类胰岛素依赖型糖尿病(IDDM)和干燥综合征的典型模型。在具体目标1中，我们将使用激光捕获显微切割(LCM)和基因分析技术来确定HEV内皮细胞在炎症的胰岛、唾液腺和泪腺中趋化因子的表达模式。这些趋化因子(及其受体)在淋巴细胞迁移到炎症组织中的作用将在功能研究中进行评估，包括体外淋巴细胞黏附试验和体内单抗抑制或趋化因子脱敏的迁移研究。在特定目标2下，我们将使用LCM和基因芯片分析来识别和表征HEV在自身免疫介导的靶器官损伤部位以组织选择性或炎症特异性方式表达的基因。我们最感兴趣的是编码新的黏附或激活分子的基因，这些分子可能介导淋巴细胞迁移到发炎的胰岛、唾液和泪腺。这些研究将为包括IDDM和干燥综合征在内的自身免疫性疾病的炎症和靶器官损伤的预防确定新的治疗目标。

The migration of autoreactive and effector lymphocytes from blood into target organs is a key event in the initiation and maintenance of target organ damage in autoimmune diseases. This migration involves a complex adhesion cascade with sequential lymphocyte/endothelial adhesion and activation events. Our goals are to identify adhesion triggering chemokines and novel activating and adhesion molecules expressed by high endothelial venules (HEV) in sites of autoimmune-mediated inflammation and tissue destruction, and to define the roles of these molecules in lymphocyte migration to these sites. We will use nonobese diabetic (NOD) mice, a well-characterized model for human insulin dependent diabetes mellitus (IDDM) and Sjogren's syndrome, as a model to define the unique endothelial molecules involved in lymphocyte migration to inflamed pancreatic islets, salivary gland and lacrimal gland. In Specific Aim 1, we shall use laser capture microdissection (LCM) and gene analysis techniques to define the patterns of chemokine expression by HEV endothelial cells in inflamed islets, salivary gland and lacrimal gland. The roles of these chemokines (and their receptors) in lymphocyte migration to inflamed tissues will be assessed in functional studies, including in vitro assays of lymphocyte adhesion and in vivo migration studies with mAb- inhibition or chemokine desensitization. Under Specific Aim 2, we shall use LCM and gene microarray analyses to identify and characterize genes that are expressed in a tissue-selective or inflammation-specific manner by HEV in sites of autoimmune- mediated target organ damage. We are most interested in genes encoding novel adhesion or activating molecules that may mediate lymphocyte migration into inflamed pancreatic islets and salivary and lacrimal gland. These studies will define novel therapeutic targets for the prevention of inflammation and target organ damage in autoimmune diseases including IDDM and Sjogren's syndrome.