INTEGRINS AND T CELL DEVELOPMENT AND FUNCTION

本提案的主要目标是确定以下方面的作用： 整合素受体在T淋巴细胞的发育和功能中的作用。 已经选择了体内和体外方法的组合。在 为了检测整合素受体功能在T细胞中的作用， 发展，转基因小鼠已经产生了显性 整合素的阴性形式。具体来说，该实验室正在使用一种 连接有活性整合素β 1胞质结构域的构建体 tac抗原的细胞外结构域，其破坏了 细胞外基质和细胞外基质之间的跨膜连接 由整合素受体提供的细胞骨架。近端lck 启动子已被选择来指导胸腺特异性表达这种 在转基因小鼠中构建，导致转基因小鼠的数量减少， 这些小鼠中的成熟、单一阳性胸腺细胞与 正常的电梯伙伴我们的假设是，这种赤字代表了缺乏 在转基因小鼠中的积极选择，我们将测试， 使用具有T单等位基因表达转基因小鼠的假设 细胞受体（TCR），具有确定的抗原识别。取决于 遗传背景，条件可以建立在其中成熟 胸腺细胞仅通过单等位基因的正选择产生， 克隆由于正选择已经显示需要p2lras， 转基因小鼠表达显性阴性形式的衔接子 将产生Shc蛋白，其应阻断整合素信号传导， P21角在体外，分子方法来剖析整合素信号传导 将进行T细胞的共刺激功能的途径。使用 最近开发的报告结构，相对于FAK的作用 TCR整合素的活化在共刺激中对所选择的细胞具有协同作用。 ECM基质，以及这种信号传导在慢性炎症中可能发挥的作用。 炎症性疾病。

The broad goals of this proposal are to determine the roles for integrin receptors in the development and function of T-lymphocytes. A combination of in vivo and in vitro approaches have been chosen. In order to test the role of integrin receptor function in T cell development, transgenic mice have been produced with a dominant negative form of integrin. Specifically, this laboratory is using a construct with the active integrin beta 1 cytoplasmic domain connected to the extracellular domain of the tac antigen, which breaks the transmembrane connection between extracellular matrix and the cytoskeleton provided by integrin receptors. The proximal lck promoter has been chosen to direct thymic specific expression of this construct in transgenic mice, leading to a reduction in the number of mature, single positive thymocytes in these mice as compared to normal liftermates. Our hypothesis is that this deficit represent a lack of positive selection in the transgenic mice, and we will test that hypothesis using transgenic mice with monoallelic expression of a T cell receptor (TCR) with a defined antigen recognition. Depending on the genetic background, conditions can be established in which mature thymocytes are produced only by positive selection of the monoallelic clones. Since positive selection has been shown to require p2lras, transgenic mice expressing a dominant negative form of the adaptor protein Shc will be produced, which should block integrin signaling to p21 ras. In vitro, molecular approaches to dissect integrin signaling pathways in co-stimulatory function of T cells will be done. Using recently developed reporter constructs, the role of versus FAK activation in of the TCR integrins have in co-stimulation on selected ECM substratum, and the role this signaling could play in chronic inflammatory diseases.