ENDOTHELIAL MODIFICATIONS THAT REDUCE T-CELL ACTIVATION

描述(改编自调查人员的摘要)：之前的工作 已经证明人类内皮细胞(EC)可以激活 同种异体T淋巴细胞分泌IL-2并促进其增殖 触发T细胞激活的信号包括两种表达 细胞因子诱导的I类和II类主要组织相容性 复合体(MHC)分子(用于激活CD8+和CD4+T细胞， 分别)和膜“共刺激分子”分子，包括LFA-3 (CD58)和尚未鉴定的蛋白质。在此应用程序中，它们 建议使用单抗阻断策略来识别 参与CD4+和CD8+T细胞活化的其他分子 同种异体EC再优化降低表达条件 在这些分子中，使用反义寡核苷酸，逆转录病毒编码 反义RNA、伯胺或“诱饵”启动子寡核苷酸。他们 将在建立的四种体外试验中测试这种改良的EC 淋巴细胞活化以确定激活T细胞的能力是否 相应地减少。具体地说，他们将检测：T细胞 同种异体EC诱导增殖；诱导T细胞产生IL-2 异体EC；T细胞产生IL-2的极限稀释法 同种异体EC诱导及EC介导的T细胞IL-2共刺激 由植物血凝素诱导产生。他们将检查人体内的EC 皮肤或人造血管网络中被移植到 以前或之后用人类免疫重建的SCID小鼠 系统，测试EC在体内激活T细胞的能力。 最后，该模型将被用于确定修改后的EC是否具有 导致T细胞活化和免疫介导性损伤的能力降低 在活体内，用高分辨率形态学技术进行评估。这些 实验可以作为减少免疫调节的新方法。 损伤，并可能为EC移植开辟新的途径。

DESCRIPTION (Adapted from the investigator's abstract):The previous work has demonstrated that human endothelial cells (EC) can activate allogeneic T lymphocytes to secrete IL-2 and to proliferate.The EC signals involved in triggering T cell activation include expression both of cytokine-inducible class I and class II major histocompatibility complex (MHC) molecules (for activation of CD8+ and CD4+ T cells, respectively) and of membrane "costimulator" molecules, including LFA-3 (CD58) and as yet unidentified proteins. In this application, they propose to use monoclonal antibody blocking strategies to identify additional molecules involved in CD4+ and CD8+ T cell activation by allogenic EC and then to optimize conditions for reducing the expression of such molecules, using antisense oligonucleotides, retrovirus encoded antisense RNA, primary amines or "decoy" promoter oligonucleotides. They will test such modified EC in four established in vitro assays of lymphocyte activation to determine if the ability to activate T cells is correspondingly reduced.Specifically, they will assay: T cell proliferation induced by allogenic EC; T cell IL-2 production induced by allogeneic EC; limiting dilution analysis of T cell IL-2 production induced by allogenic EC; and EC-mediated costimulation of T cell IL-2 production induced by phytohemagglutinin. They will examine EC in human skin or in synthetic vascular networks that have been transplanted into SCID mice previously or subsequently reconstituted with a human immune system, to test for the ability of EC to activate T cells in vivo. Finally, this model will be used to determine whether modified EC have reduced ability to cause T cell activation and immune-mediated injury in vivo, assessed by high resolution morphologic techniques. These experiments could serve as a new approach to reducing immune-mediated injury, and may open new approaches for EC transplantation.