Novel anti-inflammatory mesothelial signaling to the spleen

向脾脏发出新型抗炎间皮信号

基本信息

批准号：
10092954
负责人：
Paul Michael O'Connor
金额：
$ 23.1万
依托单位：
AUGUSTA UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2020
资助国家：
美国
起止时间：
2020-02-01 至 2023-01-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10092954
关键词：
Anti-Cholinergics Anti-Inflammatory Agents Biological Blood Breeding Cell Communication Cells Collagen Communication Complex Cytoplasm Data Development Disease Distal Elements Endotoxins Fibrosis Flow Cytometry Functional disorder Genes Goals Homologous Gene Hospitalization Hour Immune Immune response Incidence Infection Inflammation Inflammatory Inflammatory Response Institution Knock-out Laboratories Life Liver LoxP-flanked allele Lung Mediating Mesothelial Cell Mesothelium Mus Nerve Plexus Neurons Nicotinic Receptors Operative Surgical Procedures Organ Organelles Pathogenesis Pathway interactions Patients Peritoneum Phenotype Physiological Positioning Attribute Rattus Reflex action Reporting Reticuloendothelial System Sepsis Shock Signal Pathway Signal Transduction Site Source Spleen Stimulus Surgical incisions System TNF gene Testing Tissues WT1 gene alpha-bungarotoxin receptor cell type cholinergic cost cytokine ileum mortality nerve supply novel novel therapeutic intervention promoter relating to nervous system response splenic capsule systemic inflammatory response

项目摘要

Project Summary/Abstract Sepsis is a complex lethal condition defined as “life- threatening organ dysfunction caused by a dysregulated host response to infection”. In the U.S, sepsis is related to ~1 million hospitalizations annually, and the incidence of sepsis continues to rise. The mortality rate from in patients with sepsis remains unacceptably high. Novel data from our laboratory recently demonstrated that simply moving the spleen to midline and then returning it to its original position causes development of splenic capsular fibrosis and a pro-inflammatory shift in the immune cell phenotype of the spleen. While similar findings have been reported in mice, it remains unclear how these maneuvers promote a pro-inflammatory phenotype. Our novel data indicate that specialized mesothelial cells that form connections to the splenic capsule may transmit tonic anti-inflammatory signals to spleen via cholinergic signaling through alpha 7 nicotinic receptors. In addition to markers of cholinergic signaling, these mesothelial cells strongly express neuronal markers and display neuronal-like organelles within their cytoplasm. As the connections themselves are made of collagen lined with mesothelial cells, splenic capsular fibrosis following disruption of these connections may represent a physiological response to try to re-establish mesothelial cell to cell signaling. The primary goal of this proposal is to determine whether cholinergic signaling through specialized mesothelial cells does indeed transmit tonic anti-inflammatory signals to the splenic capsule and whether disruption of this signaling has a functional response, exacerbating the systemic inflammatory response to endotoxin. As such, Aim 1 will test whether `Surgical disruption of mesothelial signaling to the splenic capsule results in a prolonged anti-inflammatory profile and exacerbated inflammatory response to endotoxin'. We will access the spleen in rats via a flank incision and clear the spleen of mesothelial connections without interfering with the spleen. Baseline immune profiles (flow cytometry/cytokine analysis) and the physiological response to experimental inflammatory shock (endotoxin) in anesthetized disrupted and sham surgical rats will be determined 24 hours, 21 days and 3 months following surgical disruption of mesothelial connections to the spleen Aim 2 will test whether `Non-neuronal cholinergic signaling between mesothelial cells mediates a tonic anti-inflammatory response in the spleen'. Global deletion of α7nAChR in mice results in a pro-inflammatory splenic phenotype however, the cell type(s) mediating this effect remain unclear. We will use Wilms tumor 1 homolog gene promoter Cre and Chrna7tm1 floxed mice to `knockout' α7nAChR specifically in mesothelial cells. We predict that loss of the α7nAChR specifically in mesothelial cells will promote a pro-inflammatory phenotype in the spleen. If our hypothesis is correct, neuronal like signaling between distal sites through mesothelial cells would represent a previously unrecognized pathway of biological communication and would likely have a major impact not only on our understanding of the factors that regulate systemic immune responses in sepsis, but also idiopathic fibrosis of other organs involving the mesothelium.

项目摘要/摘要败血症是一种复杂的致命状况，定义为“威胁生命的器官功能障碍，由失调引起宿主对感染的反应”。在美国，败血症每年约有100万个住院败血症继续上升。败血症患者的死亡率仍然不可接受。新数据最近，我们的实验室表明，仅将脾脏移至中线，然后将其归还给它原始位置会导致脾囊纤维化的发展和免疫电池的促炎性转移脾脏的表型。尽管在小鼠中已经报道了类似的发现，但尚不清楚这些演习促进了促炎的表型。我们的新数据表明专门的间皮细胞与脾囊的连接形式可能会传递补品抗炎信号胆碱能信号通过α7烟碱受体。除了胆碱能信号的标记，这些间皮细胞强烈表达神经元标记，并在其细胞质中显示神经元样细胞器。由于连接本身是由胶原蛋白衬有间皮细胞的胶原蛋白，脾胶囊纤维化这些连接破坏后，可能代表了试图重新建立的物理响应间皮细胞到细胞信号传导。该提案的主要目标是确定胆碱能信号是否通过专门的间皮细胞确实确实将补品抗炎信号传递到脾囊以及该信号的破坏是否具有功能响应，加剧了全身性炎症对内毒素的反应。因此，AIM 1将测试``间皮上信号传导是否对脾胶囊会导致长时间的抗炎特征和对内毒素'的炎症反应加剧。我们将通过侧面切口进入大鼠的脾脏干扰脾脏。基线免疫谱（流式细胞术/细胞因子分析）和生理麻醉和假手术大鼠中对实验性炎症性休克（内毒素）的反应在外科手术中断到与 SLEEN AIM 2将测试间皮细胞之间的非神经元胆碱能信号传导是否介导了补品脾脏中的抗炎反应。小鼠中α7NACHR的全球缺失导致促炎性然而，脾表型，介导这种作用的细胞类型尚不清楚。我们将使用Wilms肿瘤1 同源基因启动子Cre和ChrNA7TM1在间皮细胞中专门针对“基因敲除”α7NACHR。我们预测，在间皮细胞中特别专门的α7NACHR丢失将促进促炎的表型在脾脏中。如果我们的假设是正确的，则神经元像远端位点之间通过间皮细胞的信号传导将代表以前未知的生物交流途径，可能会有一个主要不仅会影响我们对调节败血症系统性免疫反应的因素的理解，还影响其他器官的特发性纤维化涉及室硫酸盐。