IMMUNOLOGICAL ASPECTS OF HEMORRHAGE

出血的免疫学方面

• 批准号: 6519232
• 负责人: IRSHAD H CHAUDRY
• 金额: $ 37.05万
• 依托单位: UNIVERSITY OF ALABAMA AT BIRMINGHAM
• 依托单位国家: 美国
• 财政年份: 1988
• 资助国家: 美国
• 起止时间: 1988-04-01 至 2003-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6519232
• 关键词: T lymphocyte; aromatase; biological signal transduction; cellular immunity; cytokine; enzyme activity; estradiol; estrogen receptors; estrus; female; flow cytometry; hemorrhage; hormone regulation /control mechanism; hypothalamic pituitary axis; immunomodulators; laboratory mouse; macrophage; ovariectomy; prolactin; protein kinase C; raloxifene; transfection; trauma

Our recent studies indicate that proestrus female mice [with cycle- increased levels of estrogen and prolactin (PRL)] have improved immune responses after trauma-hemorrhage as opposed to markedly depressed responses in males. Moreover, the survival rate of proestrus females following sepsis after trauma-hemorrhage was significantly higher than age-matched males. In contrast to young proestrus mice, aged females (defined by lowered estradiol levels) show marked immunosuppression after trauma. Our hypothesis, therefore, is that it is the high estradiol or a high estradiol: androgen ratio which directly (receptor- mediated) or indirectly (receptor-independent) enhance immune functions in proestrus females, and the loss of these estrogenic effects may contribute to the failure to maintain immune responses in aged females after trauma-hemorrhage. Studies are proposed to determine the mechanism of regulation of estradiol and estrone by hypothalamic/pituitary factors adrenals and aromatase activity and determine how differences in estradiol levels or the estradiol: androgen ratio due to the estrus cycle, ovariectomy (OVX, in middle aged mice to reduce estrogen), and age affect immune responses after trauma. Sex steroids (SS) receptor- mediated and receptor-independent gene activation mechanisms will be studied in T-cells and macrophages (Mphi). Since activation of AF-1 and AF-2 regions of estrogen receptor (ER) is critical for agonist and antagonist effects, activation of the ER agonist regions by estrogens in T-lymphocytes will be evaluated by transfection studies. Moreover, since SS non-ligand response also involve [Ca2+]i mobilization, T cells and Mphi will be examined for Ca2+ signal transduction and the expression and translocation of PKC isoforms. The release of TH1 and TH2 cytokines and IL-6 and the effects of PRL on their release in proestrus, OVX, aged, ER-, and PRL-knockout mice will also be evaluated. Additionally, the effect of SS on PRL and TH1 and TH2 cytokine-induced JAK-STAT expressions will be evaluated. Analysis of bone marrow for lymphoblastoid/myeloblastoid cell composition, and the effect of SS on the population of these cells will be determined. We will evaluate if administration of beta-estradiol, Raloxifene or PRL in vivo after trauma-hemorrhage improves the depressed immune responses in estrogen deficient mice. If a single dose is ineffective, multiple doses of these drugs with or without gonadotropin releasing hormone (GnRH) or flutamide (androgen receptor antagonist) will be administered to determine whether synergistic beneficial effects on immune responses are produced and whether the susceptibility to sepsis after trauma is decreased. Detailed mechanistic studies of T cell and Mphi functions using molecular biological techniques to determine why low estradiol fails to maintain immune functions in aged females after trauma and the use of estradiol, Raloxifene, PRL, GnRH or flutamide to restore immune functions should yield novel information and provide an innovative approach for improving the immune responses and reducing mortality from sepsis following trauma-hemorrhage in postmenopausal as well as in surgically OVX patients with low estrogen activity.

我们最近的研究表明，发情前期的雌性小鼠[具有周期- 雌激素和催乳素(PRL)水平的升高提高了免疫力 创伤出血后的反应，而不是明显的抑郁 男性的反应。此外，发情前期母猪的成活率 创伤后脓毒症后出血的发生率明显高于 年龄匹配的男性。与发情前期幼鼠相比，老年雌性小鼠 (由较低的雌二醇水平定义)表现出明显的免疫抑制 在创伤后。因此，我们的假设是，它是最高的 雌二醇或高雌二醇/雄激素比率直接(受体- 中介的)或间接的(不依赖受体的)增强免疫功能 在发情前期的雌性中，这些雌激素作用的丧失可能 导致老年女性未能维持免疫反应 在创伤-出血后。建议进行研究以确定其机制。 下丘脑/垂体因子对雌二醇和雌酮的调节作用 肾上腺和芳香酶活性并确定如何在 雌二醇水平或雌二醇/雄激素比率因发情期而异 周期，卵巢切除(OVX，中年小鼠降低雌激素)，以及 年龄影响创伤后的免疫反应。性激素(SS)受体 介导和非受体依赖的基因激活机制将是 在T细胞和巨噬细胞(Mphi)中进行了研究。由于激活了AF-1和 雌激素受体(ER)的AF-2区对激动剂和 雌激素对ER激动区的激活和拮抗作用 在T淋巴细胞中的作用将通过转基因研究进行评估。此外， 由于SS非配基反应还涉及[Ca~(2+)]i动员，T细胞 并将检查Mphi的钙信号转导和 蛋白激酶C亚型的表达和转位。TH1和TH1的释放 Th2细胞因子和IL-6及催乳素对其释放的影响 发情前期、OVX、老龄、ER和PRL基因敲除小鼠也将被评估。 此外，SS对PRL和TH1、TH2细胞因子诱导的作用 将计算JAK-STAT表达式。慢性粒细胞白血病患者的骨髓分析 淋巴母细胞/髓母细胞组成及生长抑素的影响 这些细胞的数量将被确定。我们将评估是否 术后体内应用β-雌二醇、雷洛昔芬或催乳素 创伤失血改善雌激素抑制的免疫反应 有缺陷的小鼠。如果单剂无效，则多剂 这些药物加或不加促性腺激素释放激素(GnRH)或 氟他胺(雄激素受体拮抗剂)将用于 确定对免疫反应的协同有益影响是否 以及创伤后脓毒症的易感性是否 减少了。T细胞和Mphi功能的详细机制研究 利用分子生物学技术确定为什么雌二醇水平较低 创伤后未能维持老年女性的免疫功能 使用雌二醇、雷洛昔芬、催乳素、促性腺激素释放激素或氟他胺恢复免疫 功能应该产生新的信息并提供创新的 改善免疫反应和降低死亡率的方法 创伤后脓毒症--绝经后和 手术中雌激素活性低的OVX患者。