Molecular Regulation of Inflammatory Cytokine Production in Macrophages

***背景：免疫系统的一个重要功能是启动炎症反应，这是控制损伤和启动组织修复所必需的。炎症过程通常是自我限制和调节的，以避免附带组织损伤。炎症的失调导致过度和持续的炎症，其特征是促炎细胞因子的表达升高。髓系免疫细胞（特别是巨噬细胞和中性粒细胞）通过产生包括细胞因子在内的炎症介质在炎症中发挥重要作用。控制炎症的分子机制尚未完全描述。******最近，我们发现，在体内和体外，受刚果锥虫、脂多糖（LPS）和CpG刺激的巨噬细胞产生IL-1、IL-6、IL-12和TNF时，乙酰氨基苯二胺（Berenil，一种芳香二胺）可抑制巨噬细胞产生IL-1、IL-6、IL-12。我们最近在初步研究中使用更新和更安全的二胺化合物验证了这些发现。这种全球性的抑制作用是由于丝裂原活化蛋白激酶（MAPKs，包括ERK、p38和JNK）、信号传导和转录激活因子（STAT）蛋白（STAT1和STAT3）和NFB p65亚基磷酸化下调，这些蛋白是参与促炎细胞因子产生的关键信号分子和转录因子。在LPS攻击后，Berenil也增加肺、血液和腹膜灌洗液中的中性粒细胞数量。Berenil介导中性粒细胞存活和/或数量增加的分子机制尚不清楚。******目前更新申请的总体目标是鉴定诱导炎症细胞因子的锥虫分子，并确定Berenil在体外和体内调节巨噬细胞和中性粒细胞产生炎症细胞因子的分子机制。目的是：(i)通过锥虫诱导促炎细胞因子的分子和机制（项目1），（ii）确定Berenil抑制巨噬细胞中促炎细胞因子产生的分子机制（项目2），（iii）通过评估来自各种组织的中性粒细胞的凋亡标志物，确定Berenil是否增加中性粒细胞的存活、募集和/或从骨髓中动员（项目3）******意义：拟进行的研究将确定百利尼抗炎特性的机制过程。长期目标是广泛而深入地了解调节炎症反应的机制，这可能会揭示针对炎症条件的新方法。研究项目的新颖性和所涉及的前沿技术将继续为HQP（2-3名研究生和5名本科生）的培养创造丰富的环境。**

***Background: An important function of the immune system is to initiate inflammatory response that is required to control insults and initiate tissue repair. The inflammatory process is normally self-limiting and regulated in order to avoid collateral tissue-damage. A dysregulation of inflammation results in excessive and persistent inflammation, which is characterized by elevated expression of proinflammatory cytokines. Myeloid immune cells (particularly macrophages and neutrophils) play important roles in inflammation via their production of inflammatory mediators including cytokines. The molecular mechanisms controlling inflammation have not been fully delineated.******Recently, we showed that Diminazene aceturate (Berenil, which is an aromatic diamidine), inhibits IL-1, IL-6, IL-12 and TNF production by macrophages in vivo and in vitro following stimulation with Trypanosoma congolense, lipopolysaccharide (LPS) and CpG. We recently in preliminary studies validated these findings using newer and safer diamidine compounds. This global suppressive effect was due to downregulation of phosphorylation of mitogen-activated protein kinases (MAPKs, including ERK, p38 and JNK), signal transducer and activator of transcription (STAT) proteins (STAT1 and STAT3) and NFB p65 subunit, which are key signaling molecules and transcription factors involved in the production of proinflammatory cytokines. Berenil also increases neutrophil numbers in lungs, blood and peritoneal lavage fluids following LPS challenge. The molecular mechanisms through which Berenil mediates increased neutrophil survival and/or number is unknown. ******The overarching goal of the current renewal application is to identify trypanosome molecule(s) that induce inflammatory cytokines and determine molecular mechanisms by which Berenil regulates inflammatory cytokine production by macrophages and neutrophils in vitro and in vivo. The objectives are: (i) to dissect the molecules and mechanisms through trypanosomes induce proinflammatory cytokines (Project 1), (ii) determine molecular mechanisms through which Berenil suppresses proinflammatory cytokine production in macrophages (Project 2) and (iii) determine whether Berenil increases neutrophil survival, recruitment and/or mobilization from the bone marrow by assessing markers of apoptosis in neutrophils from various tissue (Project 3). ******Significance: The proposed studies will establish the mechanistic processes involved in the anti-inflammatory properties of Berenil. The long-term vision is to have a broad and in-depth understanding of mechanisms that regulate inflammatory responses, which may reveal novel ways of targeting inflammatory conditions. The novelty of the research project and the cutting edge technologies involved will continue to create a rich environment for the training of HQP (2-3 graduate and 5 undergraduate students). **