STAPHYLOCOCCAL TOXINS AND IL8 AND ARDS

成人呼吸窘迫综合征(ARDS) 在美国，每年大约有15万人， 以个体肺功能的急性恶化为特征的 他们已经在临床上生病了。有几条证据表明 中性粒细胞可能影响急性胰腺炎的发病和/或严重程度。 肺损伤。白介素8(IL-8)是急性脑出血的重要介质。 炎症，因为它既是趋化因子，又是激活因子 中性粒细胞。在远端有IL-9浓度升高。 大多数ARDS患者的空域。这些升高的IL-8 浓度与中性粒细胞的数量以及 死亡率，这种相关性不是总蛋白质所能比拟的 在空中集中注意力。败血症是最常见和最致命的 易患急性呼吸窘迫综合征，革兰氏阴性和- 血流中的阳性细菌能够引起扩散 肺损伤。他们体内的IL-8浓度明显较高 脓毒症ARDS患者的肺水肿液与ARDS患者的比较 在没有败血症的情况下。有相当大比例的患者患有 ARDS有一种潜在的金黄色葡萄球菌感染，至少有两种来自 金黄色葡萄球菌刺激人肺泡细胞产生IL-8 巨噬细胞。在这些研究中，我们将确定哪些细胞来自 肺环境能够产生IL-8以响应葡萄球菌 毒素。首先，将使用不同类型的细胞在体外进行评估 在培养和分析培养液中是否存在IL-8蛋白和 活动。提纯的毒素随后将被静脉注射到 兔(模拟非肺部来源的金黄色葡萄球菌感染)，以及 该毒素诱导IL-8在体内蓄积增加的能力 将确定肺泡间隙和/或肺损伤。肺部将会 然后进行免疫细胞化学和原位杂交检查 确定哪些细胞受到毒素刺激的技术 体内产生IL-8。此外，使用特定的多肽抑制剂 IL-8受体和IL-8反义寡核苷酸抑制剂 生产，我们将能够确定IL-8在 损伤的发展。然后我们将使用基因敲除技术 以确定是否通过特异性地抑制毒素的产生 这种细菌可以防止细菌伤害肺部。这些 研究将揭示葡萄球菌毒素和IL-8在 与ARDS相关的肺损伤。如果有因果关系 白介素08与急性呼吸窘迫综合征的关系及药物调控 这一重要细胞因子的表达和/或功能 我们开发的多肽和寡核苷酸可能会减少 与这种综合征相关的死亡率超过50%。

The Adult Respiratory Distress Syndrome (ARDS) which affects approximately 150,000 individuals in the United States annually, is characterized by an acute deterioration of lung function in individuals who are already clinically ill. Several lines of evidence suggest that neutrophils may influence the initiation and /or severity of the acute lung injury. Interleukin-8 (IL-8) is an important mediator of acute inflammation because it is both a chemotactic and activating factor for neutrophils. There are elevated concentrations of IL-9 in the distal airspaces of most patients with ARDS. These elevated IL-8 concentrations are correlated with the number of neutrophils as well as the mortality rate, a correlation not paralleled by total protein concentration in the airspaces. Sepsis is the most common and lethal predisposing clinical condition for ARDS, both Gram-negative and - positive bacteria in the bloodstream are capable of inducing diffuse lung injury. The are significantly higher concentrations of IL-8 in the pulmonary edema fluid of patients with ARDS from sepsis than from ARDS in the absence of sepsis. A significant proportion of patients with ARDS have an underlying S.aureus infection, and at least two toxins from S.aureus can stimulate the production of IL-8 by human alveolar macrophages. In these studies we will determine which cells from the lung environment are able to produce IL-8 in response to staphylococcal toxins. First this will be assessed in vitro using different cell types in culture and analyzing the media for the presence of IL-8 protein and activity. The purified toxin will then be administered intravenously to rabbits (to mimic a S.aureus infection of non-pulmonary origin), and the ability of the toxin to induce an increase in IL-8 accumulation in the alveolar spaces and/or lung injury will be determined. The lungs will then be examined with immunocytochemical and in situ hybridization techniques to determine which cells are stimulated by the toxins to produce IL-8 in vivo. Furthermore, using specific peptide inhibitors of the IL-8 receptors, and antisense oligonucleotide inhibitors of IL-8 production, we will be able to determine the role of IL-8 in the development of the injury. We will then use genetic knockouts in S.aureus to determine if specifically inhibiting the toxin production by the bacteria prevents the bacteria from injuring the lung. These studies will reveal the involvement of staphylococcal toxins and IL-8 in the lung injury associated with ARDS. If there is a causative relationship between IL-08 and ARDS, pharmacological control of the expression and/or function of this important cytokine, using the peptides and oligonucleotides which we have developed, may reduce the greater that 50% mortality rate associated with this syndrome.