Opioid-Mediated Fas Expression in Lymphocyte Apoptosis

描述(申请人提供)：太空飞行对 人类、猴子和啮齿动物的免疫系统。几个因素包括 微重力、缺乏承重、应力、加速力和 辐射已被认为有助于免疫系统的改变。 系统。然而，这些因素影响免疫的确切机制 制度尚待建立。用地面动物模拟这些因素 模型(例如，啮齿类动物的后肢悬挂)已被用来复制 航天飞行对免疫系统的影响。我们最近的研究表明 阿片类药物可诱导Fas的表达。此外，小鼠的束缚应激 内源性阿片依赖诱导Fas介导的脾细胞凋亡 举止。因为太空飞行条件在生理上和心理上都很相似 对人类和动物的压力，我们假设免疫抑制在 太空飞行是Fas表达增加诱导的结果 内源性阿片类药物的生产。我们提出以下目标来测试这一点 假设： 1)确定内源性阿片类药物在以下引起的淋巴细胞减少中的作用 后肢悬吊。在停药后的不同时间，对小鼠进行治疗 阿片受体拮抗剂。将从外周血中分离淋巴细胞 血液、脾和淋巴结，并检测淋巴细胞数量， 对有丝分裂刺激的反应性和细胞因子的产生 (干扰素-γ、肿瘤坏死因子和白介素2)和抗体。细胞的凋亡数 脾和淋巴结将被确定。2)内源性阿片类药物 太空飞行中的生产还没有被研究过，我们将确定 内源性阿片类物质的水平，如β-内啡肽、强啡肽和脑啡肽 在后肢悬吊后的不同时间。3)我们会 确定给予抗Fas配体抗体还是可溶性 重组Fas蛋白阻断后肢悬吊诱导的淋巴细胞 还原。此外，Fas和FasL在慢性应激动物模型中的表达 后肢悬吊也将通过Northern印迹分析和表面分析进行检查 染色。此外，带有Fas或FasL突变的小鼠将被用于验证 Fas在这一过程中的作用。这些研究的总体目标是 确定地面相关免疫抑制的潜在机制(S) 通过内源性阿片类药物调节的淋巴细胞模拟太空飞行 细胞凋亡。这些结果应该有助于理解太空的影响。 飞行环境对人体免疫系统的影响。

DESCRIPTION (provided by applicant): Space flight has profound effects on the immune system of humans, monkeys and rodents. Several factors including microgravity, lack of load-bearing, stress, acceleration forces, and irradiation have been proposed to contribute to the changes of the immune system. However, the exact mechanisms by which these factors affect the immune system remain to be established. Simulation of these factors with ground animal models (e.g., hindlimb suspension in rodents) has been used to replicate the effects of space flight on immune system. Our recent studies have shown that opioids could induce Fas expression. In addition, restraint stress in mice induces Fas-mediated apoptosis in splenocytes in an endogenous opioid-dependent manner. Since space flight conditions resemble both physical and psychological stress to humans and animals, we hypothesize that immunosuppression during space flight is a result of the expression of Fas induced by increased production of endogenous opioids. We propose the following aims to test this hypothesis: 1) Determine the role of endogenous opioids in lymphocyte reduction induced by hindlimb suspension. At different times after suspension, mice will be treated with opioid receptor antagonists. Lymphocytes will be isolated from peripheral blood, spleen, and lymph nodes, and assayed for lymphocyte number, responsiveness to mitogenic stimulation, and the production of cytokines (INF-gamma, TNF, and IL-2) and antibodies. The number of apoptotic cells in the spleen and lymph nodes will be determined. 2) Since endogenous opioid production during space flight has not been studied, we will determine the level of endogenous opioids such as beta-endorphins, dynorphin, and enkephalin at different times after subjection to hindlimb suspension. 3) We will determine whether administration of anti-Fas ligand antibody or soluble recombinant Fas protein could block hindlimb suspension-induced lymphocyte reduction. In addition, the expression of Fas and FasL in animals subjected to hindlimb suspension will also be examined by northern blot analysis and surface staining. Furthermore, mice with Fas or FasL mutation will be used to verify the role of Fas in this process. The overall goal of these studies is to determine the mechanism(s) underlying immunosuppression associated with ground simulation of space flight, via endogenous opioids-modulated lymphocyte apoptosis. The results should lead to an understanding of the effects of space flight environment on human immune system.