IMMUNOLOGICAL ASPECTS OF HEMORRHAGE

出血的免疫学方面

• 批准号: 6385647
• 负责人: IRSHAD H CHAUDRY
• 金额: $ 36.14万
• 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/6385647
• 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) 水平的增加]改善了免疫力 创伤出血后的反应而不是明显的抑郁 男性的反应。 此外，发情前期雌性的存活率 创伤出血后败血症的发生率显着高于 年龄匹配的男性。 与年轻的发情前期小鼠相比，老年雌性小鼠 （由雌二醇水平降低定义）显示出明显的免疫抑制 外伤后。 因此，我们的假设是，它是高 雌二醇或高雌二醇：雄激素比例直接（受体- 介导）或间接（非受体依赖性）增强免疫功能 在发情前期的女性中，这些雌激素作用的丧失可能会 导致老年女性无法维持免疫反应 外伤出血后。建议进行研究以确定其机制 下丘脑/垂体因素对雌二醇和雌酮的调节 肾上腺和芳香酶活性并确定差异如何 由于发情而产生的雌二醇水平或雌二醇：雄激素比率 周期、卵巢切除术（OVX，用于中年小鼠以减少雌激素），以及 年龄影响创伤后的免疫反应。 性类固醇（SS）受体- 介导且不依赖于受体的基因激活机制将是 在 T 细胞和巨噬细胞 (Mphi) 中进行研究。自从 AF-1 激活以来 雌激素受体 (ER) 的 AF-2 区域对于激动剂和 拮抗作用，雌激素激活 ER 激动剂区域 T 淋巴细胞中的变化将通过转染研究进行评估。 而且， 由于 SS 非配体反应也涉及 [Ca2+]i 动员，T 细胞 和 Mphi 将检查 Ca2+ 信号转导和 PKC亚型的表达和易位。 TH1的发布和 TH2细胞因子和IL-6以及PRL对其释放的影响 发情前期、OVX、老年、ER 和 PRL 敲除小鼠也将被评估。 此外，SS 对 PRL 以及 TH1 和 TH2 细胞因子诱导的影响 将评估 JAK-STAT 表达式。骨髓分析 淋巴母细胞/骨髓母细胞组成，以及 SS 对 这些细胞的数量将被确定。 我们将评估是否 体内给予β-雌二醇、雷洛昔芬或PRL后 创伤出血改善了雌激素抑制的免疫反应 缺乏的老鼠。 如果单次服用无效，可多次服用 这些药物含有或不含促性腺激素释放激素 (GnRH) 或 氟他胺（雄激素受体拮抗剂）将给予 确定对免疫反应是否具有协同有益作用 外伤后是否易患败血症？ 减少了。 T 细胞和 Mphi 功能的详细机制研究 使用分子生物学技术确定雌二醇低的原因 老年女性在创伤后无法维持免疫功能 使用雌二醇、雷洛昔芬、PRL、GnRH 或氟他胺恢复免疫 功能应该产生新颖的信息并提供创新的 改善免疫反应并降低死亡率的方法 绝经后以及创伤出血后的脓毒症 雌激素活性低的 OVX 手术患者。