Mechanism and prevention of lipopolysaccharide-induced early pregnancy complications

脂多糖诱发早孕并发症的机制及预防

• 批准号: 10192774
• 负责人: Bibhash Chandra Paria
• 金额: $ 41.71万
• 依托单位: VANDERBILT UNIVERSITY MEDICAL CENTER
• 依托单位国家: 美国
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-09-04 至 2023-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10192774
• 关键词: Alkaline Phosphatase; Anti-Bacterial Agents; Anti-Inflammatory Agents; Antibodies; Bacteria; Bacterial Infections; Bacterial Toxins; CD14 Antigen; CD14 gene; Cell Surface Proteins; Cell surface; Cells; Clinical; Coculture Techniques; Complex; Coupled; Cytokine Gene; Decidua; Decidual Cell; Defect; Dendritic Cells; Development; Drug Metabolic Detoxication; Drug usage; Economics; Embryo; Endotoxins; Epithelial; Escherichia coli; Female; Fetal health; Genes; Hematopoietic; Homeostasis; IL6 gene; Impairment; Infection; Infectious Agent; Inflammation; Inflammatory; Injections; Interleukin-1 beta; Isoenzymes; Late pregnancy; Lipid A; Lipopolysaccharides; Maternal Health; Mediating; Medical; Modeling; Mothers; Mus; Neutrophil Infiltration; Neutrophilic Infiltrate; Placenta; Population; Positioning Attribute; Pregnancy; Pregnancy Complications; Pregnancy Maintenance; Premature Birth; Prevention; Production; Psyche structure; Publications; Publishing; Recombinants; Research; Role; Signal Pathway; Signal Transduction; Site; Source; Spontaneous abortion; Supplementation; TLR4 gene; TNF gene; Technology; Testing; Therapeutic; Tissues; Uterus; Virulence Factors; adverse pregnancy outcome; cell type; chemokine; combat; cytokine; early pregnancy; early pregnancy loss; experimental study; improved; insight; migration; natural Blastocyst Implantation; neutrophil; novel; novel strategies; pathogen; preclinical study; prenatal; recruit; response; social; stillbirth; success; tool

PROJECT SUMMARY The available evidence suggests that intrauterine and/or maternal bacterial infection is a major cause of early and late pregnancy complications. Current antibacterial and anti-inflammatory drugs used to treat bacterial infection during pregnancy are considered harmful to maternal and fetal health. Thus, continued research to look for better treatment options to avoid bacterial infection-induced pregnancy complications is alluring. The decidua and placenta are uniquely positioned at the maternal-embryonic interface to serve as a first line of defense against bacterial toxins, but their defensive mechanisms against bacterial toxins are poorly understood. Lipopolysaccharide (LPS) is an endotoxin of Gram-negative E. coli that is associated with infection-induced pregnancy defects. LPS recognition by cell surface proteins is an important step required for the initiation of its inflammatory signaling or inactivation by cell surface molecules. Our preliminary results establish that: 1) the uterine luminal epithelium, decidua and placenta express the LPS sensing and signaling TLR4/CD14/MD2 complex; 2) LPS injection on day 5 of pregnancy terminates pregnancy by day 8 via selective-activation of the MyD88-dependent TLR4 signaling pathway at the embryo implantation site (EIS); 3) LPS induces expression of proinflammatory cytokine genes such as Tnf-α & Il-1β, chemokine genes such as Cxcl1&2, and neutrophil recruitment to the EIS; 4) cell surfaces of the decidua and placenta express tissue- nonspecific alkaline phosphatase (TNAP) isozyme that is capable of dephosphorylating LPS; 5) dephosphorylated LPS is non-inflammatory and non-toxic to murine pregnancy; and 6) AP isozyme treatment alleviates LPS-induced early pregnancy loss in mice. These preliminary findings have led to the hypothesis that LPS-induced microenvironment disruption at the early EIS is a result of concerted action of resident decidual cells and recruited neutrophils, and LPS detoxification by supplementation and/or induction of TNAP production/activity may abrogate LPS-mediated early pregnancy defects/loss. To test our hypothesis, we have proposed three mechanistic aims. In Aim 1, we will use Cre-lox and antibody- mediated neutralization technologies to establish that an important step in the development of LPS-induced unwanted inflammation at the early EIS is decidual cell-type-dependent recruitment of inflammatory neutrophils. In Aim 2, we will generate novel female mice with uterine deletion of TNAP gene Alpl to determine whether endogenous TNAP deficiency in the uterus augments the response to LPS. In Aim 3, we will examine the potential of TNAP and its activator or inducer in mitigating LPS- or E. coli-induced early pregnancy defects/loss. Upon completion of these aims, we hope to gain: 1) insights into the mechanisms of infection-induced inflammation at the early EIS; and 2) develop a novel LPS-detoxification therapeutic strategy to avoid bacteria- induced early pregnancy complications.

项目摘要 现有证据表明，宫内和/或材料细菌感染是早期的主要原因 和晚期怀孕并发症。目前用于治疗细菌的抗菌和抗炎药 怀孕期间的感染被认为对孕产妇和胎儿健康有害。那继续研究 寻找更好的治疗选择，以避免细菌感染引起的妊娠并发症是诱人的。 决策和plapeta唯一位于母体 - 胚胎界面，以作为第一行 防御细菌毒素，但它们针对细菌毒素的防御机制很差 理解齿。脂多糖（LPS）是革兰氏阴性大肠杆菌的内毒素，与之相关 感染引起的妊娠缺陷。通过细胞表面蛋白识别的LPS识别是需要的重要步骤 其炎症信号传导或细胞表面分子灭活的倡议。我们的初步结果 确定：1）子宫腔上皮，decidua和plapeta表达LPS灵敏度和信号传导 TLR4/CD14/MD2复合物; 2）在怀孕第5天注射LPS在第8天通过 在胚胎植入部位（EIS）的MyD88依赖性TLR4信号通路的选择性激活； 3） LPS诱导促炎性细胞因子基因（例如TNF-α和IL-1β）的表达，趋化因子基因，例如 CXCL1＆2，以及EIS的中性粒细胞招募； 4）决策的细胞表面和Pleceta表达组织 - 非特异性酒精磷酸酶（TNAP）同工酶，能够脱磷酸化的LP； 5） 去磷酸化的LPS是非炎性的，对鼠妊娠无毒。 6）AP同工酶处理 减轻LPS引起的小鼠早期妊娠丧失。这些初步发现导致了假设 EIS早期，LPS引起的微环境中断是由一致行动的结果 居民的固定细胞和招募的嗜中性粒细胞，以及通过补充和/或 TNAP产生/活性的诱导可能会消除LPS介导的早期妊娠缺陷/丧失。 为了检验我们的假设，我们提出了三个机械目标。在AIM 1中，我们将使用Cre-lox和抗体 - 介导的神经化技术，以确定LPS诱导的发展的重要步骤 EIS早期不需要的炎症是确定炎症的细胞类型依赖性募集 中性粒细胞。在AIM 2中，我们将用TNAP基因的子宫缺失生成新的雌性小鼠，以确定 子宫内源性TNAP缺乏是否会增加对LP的反应。在AIM 3中，我们将检查 TNAP及其激活剂的潜力或在减轻LPS或E. coli诱导的早期妊娠的诱导 缺陷/损失。 完成这些目标后，我们希望获得：1）对感染引起的机制的见解 EIS早期发炎； 2）制定一种新型的LPS-难毒性疗法策略，以避免细菌 - 诱发早期妊娠并发症。