Cell Interactions in the Inflamed Intestinal Mucosa

描述（由申请人提供）：多种细胞类型参与 慢性炎症反应的发展和持续。这也发生在 在炎症性肠病（IBD）中，免疫系统的长期激活 和非免疫细胞导致严重的结构和功能异常。 在上一个资助期间进行的研究已经定义了表型 和两种非免疫肠细胞的功能特征， 人肠微血管内皮细胞（HIMEC）和肠 成纤维细胞（HIF），并评估这些细胞和粘膜之间的相互作用， T细胞结果表明，HIMEC和HIF均发挥了积极的作用 通过T细胞和细胞因子结合在免疫和炎症中 生产这些观察结果有力地支持了这样一个概念， 免疫-非免疫细胞相互作用在发病机制中起着关键作用 和IBD的持续性。然而，粘膜中细胞的相互作用需要 更好地理解，特别是在招聘机制方面 刺激局部非免疫细胞的T细胞。细胞间通讯是 由多种趋化、粘附和活化分子控制， 直接运动、接触和刺激。该提案将调查 调节HIMEC和HIF衍生的T细胞募集的机制 趋化因子和这种效应的后果。CD 40 L的表达 激活的T细胞及其反受体CD 40的非免疫细胞是一种免疫抑制剂。 理想的系统，研究细胞相互作用的分子机制，在一个集成的 时尚.因此，我们将测试以下中心假设： CD 40/CD 40 L系统控制T细胞-非免疫细胞的自我维持循环 导致IBD慢性化的相互作用。这一假设将是 通过三个具体目标进行测试：1）定义T细胞趋化因子的谱 2）研究T细胞的趋化性，以响应HIMEC和HIF的表达。 HIMEC-和HIF-衍生的趋化因子; 3）鉴定受体-配体对， 信号通路介导T细胞诱导的HIMEC和HIF趋化因子的产生。 阻断CD 40或CD 40 L可能会中断免疫-非免疫的慢性循环。 IBD中发生的细胞相互作用并导致临床获益， 自身免疫和炎症的动物模型，包括 实验性IBD

DESCRIPTION (provided by applicant): Multiple cell types are involved in the development and persistence of chronic inflammatory response. This also occurs in inflammatory bowel disease (IBD), where long-standing activation of immune and non-immune cells results in severe structural and functional abnormalities. Studies performed during the last funding period have defined the phenotypic and functional characteristics of two types of nonimmune intestinal cells, human intestinal microvascular endothelial cells (HIMEC) and intestinal fibroblasts (HIF), and assessed the interaction between these cells and mucosal T-cells. The results demonstrated that both HIMEC and HIF play an active role in immunity and inflammation through binding of T-cells and cytokine production. These observations strongly support the concept that immune-nonimmune cell interactions are critically involved in the pathogenesis and persistence of IBD. However, the interplay of cells in the mucosa needs to be better understood, particularly in regard to the mechanisms of recruitment of T-cells that stimulate local nonimmune cells. Cell-to-cell communication is controlled by a variety of chemotactic, adhesion and activation molecules that direct movement, contact and stimulation. This proposal will investigate the mechanisms regulating the recruitment of T-cells by HIMEC- and HIF-derived chemokines and the consequences of this effect. The expression of CD40L by activated T-cells and of its counter-receptor CD40 by nonimmune cells is an ideal system to study molecular mechanisms of cell interaction in an integrated fashion. Therefore, we will test the following central hypothesis: The CD40/CD40L system controls a self-perpetuating cycle of T-cell-nonimmune cell interactions that contribute to chronicity of IBD. This hypothesis will be tested by three specific aims: 1) Define the spectrum of T-cell chemokines produced by HIMEC and HIF; 2) Investigate T-cell chemotaxis in response to HIMEC- and HIF-derived chemokines; 3) Identify the receptor-ligand pairs and signaling pathways mediating T-cell-induced HIMEC and HIF chemokine production. Blockade of CD40 or CD40L may interrupt the chronic cycle of immune-nonimmune cell interactions occurring in IBD and result in clinical benefits, as suggested by animal models of autoimmunity and inflammation, including experimental IBD.