Immune Tolerance; Sigma Receptor as a Therapeutic Target

描述(申请者提供)：该项目的目标是收集 支持诱导免疫耐受的新策略的证据， 即利用Sigma 1受体作为潜在的治疗靶点。西格玛1 受体被定义为各种精神活性药物的特定结合部位 如氟哌啶醇和五唑西林。这种受体最近被克隆了。 并以此为特征。它是一种膜结合蛋白，主要存在于 细胞内的位置。它在包括免疫细胞在内的各种组织中表达。 还有胎盘。有令人信服的证据表明它具有免疫抑制作用。 Sigma 1受体特异性配体。该受体在免疫中的作用 函数近年来受到越来越多的关注，因为它已经成为 显然，孕酮是该受体的内源性配体。 这个项目的目标是勾勒出 Sigma-1受体的免疫抑制功能及其可能的研究 孕酮在维持母体对胎盘耐受性中的作用 异体移植。这个项目将检验以下假设：1)黄体酮 几种药物配体抑制血管内皮细胞的功能和增殖 T淋巴细胞作为Sigma-1受体的特异性配体；2)Sigma 1受体通过影响其他细胞的功能发挥作用。 蛋白质-蛋白质相互作用在T淋巴细胞和胎盘中的蛋白质； 靶向干扰Sigma-1受体基因表达 小鼠模型中的基因会导致母体对胎盘的不耐受 异体移植。为了检验这些假说，本文提出了三个具体目标。特定的 目的1研究Sigma-1受体在静止期和活化T淋巴细胞中的表达，并探讨该受体在慢性粒细胞白血病发病中的作用。 抑制T细胞功能。这将通过分析表达式来完成 T淋巴细胞中Sigma-1受体在分子和功能水平的表达 激活前和激活后。Sigma-1受体在T细胞中的必备作用 将通过分析Sigma 1的生物学效应来评估其功能 Sigma-1受体阳性(对照)和Sigma-1中的受体特异性配体 受体阴性(稳定表达反义Sigma 1受体的转染体 M RNA)Jurkat细胞。具体目标2是鉴定人类体内的蛋白质 胎盘和与Sigma-1受体相互作用的T淋巴细胞中 酵母双杂交系统。相互作用的靶蛋白的鉴定 通过Sigma 1受体将有助于解开细胞的分子机制 Sigma 1受体介导的信号转导。具体目标3是确定，使用 Sigma 1受体基因敲除小鼠，是否表现为受体缺失 胚胎本身是致命的，胚胎没有能力保护自己 对抗母体免疫系统，或作为母体免疫系统的无能为力 维持对同种异体胎盘移植耐受性的系统。这个项目可能 具有显著的生理、临床和治疗相关性。这个 拟议的研究可能会导致更好地理解诱导 母体对同种异体胎盘移植的耐受性，可能为 研究Sigma-1治疗潜力的未来努力 受体特异性配体作为有效的免疫抑制剂。

DESCRIPTION (provided by applicant): The goal of this project is to gather evidence in support of a novel strategy for the induction of immune tolerance, namely to use sigma 1 receptor as a potential therapeutic target. Sigma 1 receptor is defined as a specific binding site for various psychoactive drugs such as haloperidol and pentazocine. This receptor has been recently cloned and characterized. It is a membrane-bound protein found primarily in intracellular sites. It is expressed in various tissues including immune cells and placenta. There is compelling evidence for an immunosuppressive role of sigma 1 receptor-specific ligands. The role of this receptor in immune function has received increasing attention in recent years as it has become apparent that progesterone is a putative endogenous ligand for this receptor. The goal of this project is to delineate the molecular events involved in the immunosuppressive function of sigma 1 receptor and to investigate the possible role of progesterone in the maintenance of maternal tolerance toward placental allograft. This project will test the following hypotheses: 1) Progesterone and several pharmacological ligands suppress the function and proliferation of T lymphocytes by acting as specific ligands for the sigma 1 receptor; 2) sigma 1 receptor produces its effects by influencing the function of other cellular proteins in T lymphocytes and placenta via protein-protein interaction; 3) Abolition of sigma 1 receptor gene expression by targeted disruption of the gene in a mouse model will lead to maternal intolerance of the placental allograft. Three specific aims are proposed to test these hypotheses. Specific Aim 1 is to study the expression of sigma 1 receptor in quiescent and activated T lymphocytes and to establish the role of this receptor in the suppression of T cell function. This will be done by analyzing the expression of sigma 1 receptor at the molecular and functional level in T lymphocytes before and after activation. The obligatory role of sigma 1 receptor in T cell function will be evaluated by analyzing the biological effects of sigma 1 receptor-specific ligands in sigma 1 receptor-positive (control) and sigma 1 receptor-negative (stable transfectants expressing antisense sigma 1 receptor mRNA) Jurkat cells. Specific Aim 2 is to identify the proteins in human placenta and in T lymphocytes that interact with sigma 1 receptor using the yeast two-hybrid system. Identification of the target proteins that interact with sigma 1 receptor will help to unravel the molecular mechanisms of cell signaling mediated by sigma 1 receptor. Specific Aim 3 is to determine, using sigma 1 receptor knockout mice, whether the absence of the receptor manifests itself as embryo lethality, an inability of the embryo to defend itself against maternal immune system, or as an inability of the maternal immune system to maintain tolerance toward the placental allograft. This project may have significant physiological, clinical, and therapeutic relevance. The proposed studies may lead to a better understanding of the induction of maternal tolerance toward placental allograft and may provide the basis for future efforts to examine the therapeutic potential of sigma 1 receptor-specific ligands as effective immunosuppressants.