IMMUNOLOGICAL ASPECTS OF HEMORRHAGE

出血的免疫学方面

• 批准号: 2857116
• 负责人: IRSHAD H CHAUDRY
• 金额: $ 38.07万
• 依托单位: RHODE ISLAND HOSPITAL
• 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/2857116
• 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; 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，发情前期雌性小鼠[周期- 增加雌激素和催乳素（PRL）的水平]可以提高免疫力， 创伤出血后的反应，而不是显着抑制 男性的反应。 此外，发情前期雌性的存活率 创伤出血后脓毒症的发生率显著高于 年龄匹配的男性 与年轻的发情前期小鼠相反， （定义为雌二醇水平降低）显示明显的免疫抑制 在创伤后。 因此，我们的假设是， 雌二醇或高雌二醇：雄激素比率，其直接（受体- 介导）或间接（受体非依赖性）增强免疫功能 在发情前期雌性中，这些雌激素效应的丧失可能 导致老年女性无法维持免疫反应 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 肾上腺素和芳香化酶的活性，并确定如何差异， 雌二醇水平或雌二醇：雄激素比例由于发情 周期，卵巢切除术（OVX，在中年小鼠中减少雌激素），以及 年龄影响创伤后的免疫反应。 性类固醇（SS）受体- 介导的和受体非依赖性的基因激活机制将是 在T细胞和巨噬细胞（Mphi）中研究。由于AF-1的激活， 雌激素受体（ER）的AF-2区域对于激动剂和 拮抗剂作用，雌激素激活ER激动剂区域 将通过转染研究来评估T淋巴细胞中的细胞毒性。 此外，委员会认为， 由于SS非配体应答也涉及[Ca2 +] i动员，T细胞 和Mphi将被检查Ca2+信号转导， PKC亚型的表达和易位。 TH1的释放和 Th2型细胞因子和IL-6以及PRL对其释放的影响 还将评价发情前期、OVX、老龄、ER-和PRL-敲除小鼠。 此外，SS对PRL和TH 1和TH 2的影响也被证实。 将对JAK-STAT表达式进行评估。骨髓分析 淋巴母细胞样/髓母细胞样细胞组成，以及SS对 将确定这些细胞的群体。 我们将评估是否 β-雌二醇、雷洛昔芬或PRL的体内给药 创伤出血改善雌激素抑制的免疫反应 缺陷小鼠 如果单次给药无效， 这些药物与或不与促性腺激素释放激素（GnRH），或 将给予氟替卡松（雄激素受体拮抗剂）， 确定对免疫应答的协同有益作用是否 以及创伤后脓毒症的易感性是否 降低 T细胞和Mphi功能的详细机制研究 用分子生物学技术来确定为什么雌二醇低 不能维持老年女性创伤后的免疫功能， 使用雌二醇、雷洛昔芬、PRL、GnRH或氟西汀恢复免疫 功能应该产生新的信息，并提供创新的 提高免疫反应和降低死亡率的方法 绝经后创伤出血后脓毒症 低雌激素活性的手术切除卵巢的患者。