MONONUCLEAR LEUKOCYTE ADHESION AND RECRUITMENT IN CHRONIC INFLAMMATORY DISEASE

来自选择素、整合素和免疫球蛋白基因的粘附受体 家庭被认为在正常和病理的 所有白细胞的募集;然而，大多数研究都集中在 中性粒细胞和急性炎性损伤。 粘连阻塞 参与募集的受体限制了 一些模型系统，特别是在肺部。 这些成功 希望类似的方法将有利于慢性炎症和 免疫介导的疾病。 然而，粘附受体可能 参与单核白细胞的募集， 这些疾病的细胞介质，尚未得到充分评价 在生理学相关的模型系统中。 从中性粒细胞中可以清楚看出 研究表明，白细胞-内皮细胞粘附必须在剪切下进行研究， 应力以确定单个粘附分子的贡献 到体内招募。 同样重要的是， 定量研究了受体阻断对相关细胞募集的影响， 慢性炎性疾病的模型，因为在体外建模，充其量， 接近体内的流动条件。 这些研究具有基础性 重要性的发展，针对招募的治疗， 慢性炎症/免疫性疾病。 我们的初步研究 识别含α 4整合素，最可能是α 4/β 1，作为关键 受体在单核白细胞附着到马槟榔处理的 剪切下的内皮。 取决于它的基础结合水平 活性，该受体要么加强E- 选择素或启动附着和募集。 前 占主导地位的循环细胞共表达反受体， 选择素和“低亲合力”α 4整联蛋白。 后者 主要用于循环“活化”单核细胞和淋巴母细胞 对抗原或炎症刺激产生反应。 在 特异性目标1（SA 1），特异性阻断单克隆抗体（mAb）， β 1链的推定“高亲合力”形式上的表位，和/或 α 4/β 1受体将在三个物种中产生。 这些mab 将对SA做出贡献204。 SA 2将探索E- 选择素，L-选择素和α 4/β 1受体在附着过程中 纯化的人单眼白细胞亚群和相关细胞系， 生理水平的线性剪切- 体外应激。 SA 3将探索细胞激活在 上调剪切下的功能和活化的表达 α/β受体上的表位。 SA 4将使用新开发的 和目前可用的特异于α 4/β 1受体的单克隆抗体， 确定该受体对单核白细胞的贡献 大鼠中聚糖诱导的肺肉芽肿的募集（协作 和J·沃伦，第三计划和P.A.沃德，项目一）和令人不安的- 诱导小鼠肺肉芽肿（与S.昆克尔， 项目二）。

Adhesion receptors from the selectin, integrin and immunoglobulin gene families are thought to be instrumental in the normal and pathologic recruitment of all leukocytes; however, most studies have focused on neutrophils and acute inflammatory injury. Blockage of adhesion receptors involved in recruitment limits neutrophil-dependent injury in a number of model systems particularly in the lung. These successes raise hope that a similar approach will benefit chronic inflammatory and immune mediated diseases as well. However, adhesion receptors likely to be involved in the recruitment of mononuclear leukocytes, the key cellular mediators of these diseases, have not been adequately evaluated in physiologically relevant model systems. It is clear from neutrophil studies that leukocyte-endothelial adhesion must be studied under shear- stress to determine the contributions of individual adhesion molecules to recruitment in vivo. It is equally important to evaluate quantitatively the impact of receptor blockade on recruitment in relevant models of chronic inflammatory disease since in vitro modeling, at best, approximates flow conditions in vivo. Such studies are of fundamental importance to the development of therapeutics targeted at recruitment in chronic inflammatory/immunologic diseases. Our preliminary studies identify alpha4-containing integrins, most likely alpha4/Beta1, as a key receptor in the attachment of mononuclear leukocytes to cytokine-treated endothelium under shear. Depending on its basal level of binding activity, this receptor either strengthens attachment initiated by E- selectin or initiates attachment and recruitment. The former predominates for circulating cells co-expressing counter-receptors for the selectins and "low avidity" alpha4 integrins. The latter predominates for circulating "activated" monocytes and lymphoblasts generated in response to antigenic or inflammatory stimulate. In Specific Aim 1 (SA 1), blocking monoclonal antibodies (mabs) specific for epitopes on the putative "high avidity" form of the Beta1 chain and/or the alpha4/beta1 receptor will be generated in three species. These mabs will contribute to SAs 204. SA 2 will explore the interactions of E- Selectin, L-Selectin and the alpha4/Beta1 receptor during attachment of purified subsets of human monocular leukocytes and related cell lines to cytokine-activated endothelium at physiologic levels of linear shear- stress in vitro. SA 3 will explore the role of cellular activation in upregulating the function under shear and expression of activation epitopes on the alpha/beta receptor. SA 4 will use the newly developed and currently available Mabs specific for alpha4/beta1 receptor to determine the contribution of this receptor to mononuclear leukocyte recruitment in glycan-induced lung granulomas in the rat (collaboration with J. Warren, project III and P.A. Ward, project I) and schistosome- induced lung granulomas in the mouse (collaboration with S. Kunkel, project II).