IMMUNOLOGICAL ASPECTS OF HEMORRHAGE

我们的研究表明，在没有组织损伤的情况下，出血会产生 细胞免疫功能明显受抑，尽管液体 复苏，持续约4天。更重要的是， Medline剖腹术(没有大量失血)也会产生 明显的免疫抑制。然而，尽管出现了明显的免疫抑制 在单纯性出血和剖腹手术后，没有 与这两种侮辱中的任何一种有关的死亡率。尽管如此， 出血后动物对脓毒症的抵挡能力降低 出血量3d后挑战。因为，在大多数临床情况下， 出血与创伤有关，我们开发了一种非肝素化的 创伤-出血与复苏相关的小鼠模型 延长免疫抑制时间(即5天)，并导致显著 复苏后6天内死亡。我们的假设是 介质，如前列腺素(如PGE2)，某些细胞因子，以及 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，就像在出血和 它们协同作用，产生长期的免疫抑制状态， 与这两种侮辱中的任何一种相比。我们的具体目标是利用 创伤、出血以及创伤-出血的小鼠模型 复苏，并确定1)循环和潜在的局部 前列腺素E_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)并确定导致延长的调解人(S 创伤出血后细胞免疫功能低下；2) Mphi和淋巴细胞细胞信号转导机制的变化 (即[Ca~(2+)]i、Ca~(2+)通量、蛋白激酶活性、IP3、ATP和循环 核苷酸水平)以及内源性阿片-内啡肽的释放；3) 环氧合酶基因表达与多种淋巴因子和细胞因子 已知具有免疫抑制和/或免疫增强作用，包括 IL-4、IL-10和转化生长因子-β。我们还将评估免疫细胞的表达 热休克蛋白以及两者的程序性细胞死亡率 成熟和未成熟细胞群体；4)库普弗细胞是否减少 通过用氯化Gd使小鼠退缩来防止 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，如钙离子拮抗剂，化学修饰的肝素， 氯喹、布洛芬、三磷酸腺苷-氯化镁、肉碱以及细胞因子 抗体/抑制物(如IL-1ra、肿瘤坏死因子结合蛋白)将有助于 剖析了迁延性免疫抑制的机制。此外，他们的 提高创伤出血后存活率的能力和减少 对随后的败血症的易感性将被确定。对.的使用 生化、生理、细胞和分子生物学技术 确定导致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.