IMMUNOLOGICAL ASPECTS OF HEMORRHAGE

我们的研究表明，没有组织创伤的出血， 细胞介导的免疫力明显下降，尽管液体 复苏，持续约4天。 此外，创伤在 Medline剖腹手术（无明显失血）也会产生 明显的免疫抑制 然而，尽管有明显的免疫抑制， 在单纯出血和剖腹手术后， 死亡率与这些侮辱有关。 尽管如此， 出血后动物表现出抵抗脓毒症的能力下降， 出血后3天攻毒。 因为，在大多数临床情况下， 出血与创伤同时发生，我们开发了一种非肝素化的 小鼠创伤出血复苏模型， 延长的免疫抑制（即，>5天），结果显著 复苏后6天内死亡。 我们的假设是 介质如前列腺素（例如，PGE 2）、某些细胞因子，和 神经内分泌成分（儿茶酚胺，糖皮质激素，内啡肽， 阿片类药物）在创伤后释放，在出血后释放， 它们协同作用以产生延长的免疫抑制状态， 相比之下，这两种侮辱单独。 我们的具体目标是利用 创伤、出血以及创伤-出血和 复苏，并确定1）循环和潜在的局部 介质如PGE 2，儿茶酚胺，皮质酮， 内啡肽、阿片类药物（吗啡和可待因）（就浓度而言， 时间，持续时间），并确定诱导延长的介质 创伤-出血后细胞介导的免疫抑制; 2） Mphi和淋巴细胞信号转导机制的改变 (i.e., [Ca2+]i、Ca 2+流动、蛋白激酶活性、IP 3、ATP和环 核苷酸水平）与内源性阿片样物质-内啡肽释放一起沿着; 3） 环氧合酶、各种淋巴因子和细胞因子的基因表达 已知具有免疫抑制和/或免疫增强作用，包括 IL-4、IL-10和TGF-β。 我们还将评估免疫细胞表达 热休克蛋白以及程序性细胞死亡率在这两个 成熟和未成熟细胞群; 4）是否减少枯否细胞 通过用氯化钆重新给小鼠注射， 增加全身炎症介质，并维持各种 创伤出血后不同细胞的免疫功能，以及 提高动物的总体存活率;以及5）是否使用 免疫调节剂如Ca 2+拮抗剂，化学修饰的肝素， 氯喹、布洛芬、ATP-MgCl 2、肉毒碱以及细胞因子 抗体/抑制剂（例如，IL-1 ra，TNF结合蛋白）将有助于 剖析免疫抑制的机制 而且他们的 提高创伤出血后生存率的能力， 将确定对随后脓毒症的易感性。 使用 生物化学、生理学、细胞和分子生物学技术， 确定长期免疫抑制的机制，器官 创伤-出血和复苏后的功能障碍和死亡率 应该为创伤的治疗和护理提供有用的信息 受害者

Our studies have shown that hemorrhage, without tissue trauma, produces a marked depression in cell-mediated immunity which, despite fluid resuscitation, persists for approximately 4 days. Moreover, trauma in the form of medline laparotomy (without significant blood loss) also produces marked immunodepression. However, despite the marked immunodepression following simple hemorrhage as well as following laparotomy, there was no mortality associated with either of these insults. Nonetheless, posthemorrhage animals exhibit decreased capacity to ward off septic challenge 3 days after hemorrhage. Since, in most clinical situations, hemorrhage occurs in conjunction with trauma, we developed a nonheparinized mouse model of trauma-hemorrhage and resuscitation which is associated with prolonged immunosuppression (i.e., >5 days) and results in significant mortality within 6 days postresuscitation. Our hypothesis is that mediators such as prostaglandins (e.g., PGE2), certain cytokines, and neuroendocrine components (catecholamines, glucocorticoids, endorphins- opioids) are released following trauma, as sell as following hemorrhage and they act synergistically to produce a prolonged state of immunodepression, as compared to either of these insults alone. Our specific aims are to use mouse models of trauma, hemorrhage, as well as trauma-hemorrhage and resuscitation, and determine 1) the circulating and potentially local profiles of mediators such as PGE2, catecholamines, corticosterone, endorphins, opioids (morphine and codeine) (with respect to concentration, timing, duration) and identify the mediator(s) which induces prolonged depression of cell-mediated immunity following trauma-hemorrhage; 2) alterations in Mphi and lymphocyte cellular signal transduction mechanisms (i.e., [Ca2+]i, Ca2+ fluxing, protein kinase activity, IP3, ATP and cyclic nucleotide levels) along with endogenous opioids-endorphins release; 3) gene expression of cyclooxygenase, and various lymphokines and cytokines known to have immunosuppressive and/or immunoenhancing effects, including IL-4, IL-10, and TGF-beta. We will also asses immune cell expression of heat shock protein as well as the rate of programmed cell death in both mature and immature cell populations; 4) whether decreasing Kupffer cell number by retreating the mice with gadolinium chloride prevents the increase in systemic inflammatory mediators, and maintains various immunological functions following trauma-hemorrhage in distinct cells, and improves the overall survival of animals; and 5) whether the use of immunomodulators such as Ca2+ antagonists, chemically modified heparin, chloroquine, ibuprofen, ATP-MgCl2, carnitine, as well as cytokine antibodies/inhibitors (e.g., IL-1ra, TNF binding protein) will aid in dissecting the mechanism of protracted immunosuppression. Moreover, their ability to improve survival following trauma-hemorrhage and to decrease susceptibility to subsequent sepsis will be determined. The use of biochemical, physiological, cellular and molecular biological techniques to determine the mechanism responsible for prolonged immunodepression, organ dysfunction and mortality following trauma-hemorrhage and resuscitation should provide useful information for the treatment and care of trauma victims.