Interplay Among NKT Cell Subsets in Alcoholic Liver Disease

NKT 细胞亚群在酒精性肝病中的相互作用

基本信息

批准号：
9115458
负责人：
Vipin Kumar
金额：
$ 34.49万
依托单位：
UNIVERSITY OF CALIFORNIA, SAN DIEGO
依托单位国家：
美国
项目类别：
财政年份：
2015
资助国家：
美国
起止时间：
2015-06-01 至 2018-07-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/9115458
关键词：
Address Adoptive Transfer Alcohol consumption Alcoholic Liver Diseases Alcoholic liver damage Animals Antigens Biological Assay Blood C57BL/6 Mouse Cell surface Cells Chronic Clinical Dependence Diet Disease Ethanol Event Flow Cytometry Gene Expression Gene Expression Profiling Genes Glycolipids Hepatic Hepatocyte Hour Human ITGAM gene ITGAX gene Immune Immune Targeting Immunity Immunotherapy Inflammation Inflammatory Injury to Liver Interleukin-17 Intervention Ischemia Knowledge Lipids Liquid substance Liver Liver diseases Lymphocyte Mediating Metabolic Modeling Mus Myeloid Cells PPAR alpha PTPRC gene Pathway interactions Patients Peroxisome Proliferators Phase Play Population Prevention Process Purinergic P1 Receptors Regulatory Pathway Role Small Interfering RNA Staining method Stains Sulfoglycosphingolipids Therapeutic Intervention Time Tissues Tretinoin anergy base chronic alcohol ingestion cytokine feeding interleukin-23 liver injury male novel novel therapeutic intervention osteopontin pathogen pre-clinical prevent problem drinker receptor research study retinoic acid receptor gamma

项目摘要

DESCRIPTION (provided by applicant): This proposal aims to understand key innate immune mechanism(s) leading to liver injury following chronic alcohol ingestion. How cellular interactions among innate immune cells in liver, including NKT cells provide both tolerance to gut or metabolic antigens and at the same time immunity against pathogens is poorly understood. NKT cells are comprised of two distinct subsets, type I and type II, and recognize different lipid antigens presented by CD1d molecules. A major subset of type II NKT cells that we identified recognizes a self-glycolipid, sulfatide. In two different models of liver injury we found that sulfatide-mediated activation of type II NKT cells leads to engagement of a novel immune regulatory pathway resulting in anergy induction in type I NKT cells, blockade of the inflammatory cascade, and inhibition of tissue damage. Here we hypothesize that differential activation of NKT cell subsets play opposing roles in liver injury and their interactions with othe innate immune cells, including DCs and myeloid cells, are decisive in orchestrating inflammatory events leading to ALD. Accordingly, we found that during the preclinical phase of ALD following chronic plus binge feeding of Lieber-DeCarli liquid diet in male C57BL/6 mice, type I but not type II NKT cells are partially activated leading to recruitment of inflammatory cells into liver. A central finding we have made is that inactivation of type I NKT cells following administration of sulfatide or all-trans retinoic acid (ATRA) blocks ALD. Furthermore, Jα18-/- mice deficient in type I NKT cells are significantly protected from liver injury. Notably, hepatic gene expression profiling revealed type I NKT-dependence of osteopontin (OPN) expression, while sulfatide enhances peroxisome proliferator-activator receptor-α (PPARα) levels in liver. Cell surface activation markers and the cytokine secretion profile of type I and type II NKT cell subsets during different phases of ALD will be examined using αGalCer/CD1d- and sulfatide/CD1d-tetramers respectively, and intracytoplasmic staining and flow cytometry. A role for IL-23/IL-17 pathway and adenosine receptor A2aR in activation of type I NKT cells will be examined. Real time PCR and Elisa assays will be used to examine activation of other innate cells in liver during preclinical and clinical phases following ethanol feeding. Adoptive transfer experiments or depletion of conventional cDC or CD11b+Gr-1+ cells, respectively in NKT cell activation and in ALD will be studied. Mechanisms by which administration of ATRA or sulfatide inhibits type I activation leading to blockade of liver damage will be investigated. Sulfatide, ATRA, retinoic acid receptor-γ (RARγ) or their combinations along with other inhibitory cytokines will be used to effectively treat ongoing liver disease. Mechanisms of NKT- mediated hepatic expression of OPN and PPARα genes common in both human and experimental ALD will be examined using siRNA and gene-deficient animals. The proposed studies will provide a better understanding of the key innate immune mechanisms centered on activation of NKT cell subsets following ethanol ingestion and should allow identification of novel immune targets for potential therapeutic intervention in ALD.

描述（应用程序提供）：该提案旨在了解关键的先天免疫力学，导致慢性酒精摄入后肝损伤。细胞相互作用如何在包括NKT细胞在内的先天免疫细胞中，既可以耐受肠道或代谢抗原的耐受性，同时对病原体的免疫学也很少了解。 NKT细胞由两种不同的亚集成，即I型和II型，并识别由CD1D分子呈现的不同脂质抗原。我们鉴定出的II型NKT细胞的主要子集识别出一种自糖脂质硫化物。在两种不同的肝损伤模型中，我们发现硫化物介导的II型NKT细胞的激活导致了一种新型免疫调节途径的参与，从而导致I型NKT细胞的反应诱导，阻断炎症级联反应，并抑制组织损伤。在这里，我们假设NKT细胞亚群的差异激活在肝损伤中起着相反的作用，并且它们与其他先天免疫小球（包括DC和髓样细胞）的相互作用在策划导致ALD的炎症事件方面具有决定性作用。根据慢性加和在雄性C57BL/6小鼠中Lieber-decarli液体饮食的临床前阶段，I型，但未部分激活II型NKT细胞，导致炎症细胞募集到肝脏中。我们提出的一个核心发现是，给予硫化硫化物或全反式视黄酸（ATRA）阻止了I型NKT细胞的灭活。此外，I型NKT细胞中的Jα18-/ - 小鼠的确定性受到明显保护的肝损伤。值得注意的是，肝蛋白（OPN）表达的I型NKT依赖性，而硫代过氧化物增殖剂 - 激活剂受体-α（PPARα）水平的I型I型NKT依赖性。在ALD不同阶段，将使用αGalcer/CD1D-和Sulfatide/CD1D-Tetramer，以及室内胞质染色和流式细胞仪，分别研究ALD不同阶段的I型和II型NKT细胞子集的细胞表面激活标记和II型NKT细胞子集的细胞因子分泌谱。将检查IL-23/IL-17途径和腺苷受体A2AR在I型NKT细胞激活中的作用。实时PCR和ELISA分析将用于检查乙醇进食后临床前和临床阶段中肝脏其他先天细胞的激活。将研究在NKT细胞激活和ALD中分别研究常规CDC或CD1B+ GR-1+细胞的产物转移实验或耗竭。将研究ATRA或亚硫酸抑制I型激活的机制，从而研究导致肝脏损伤的阻塞。亚硫酸盐，阿特拉，视黄酸受体-γ（RARγ）或其组合以及其他抑制性细胞因子将用于有效治疗持续的肝病。将使用siRNA和基因缺陷动物检查NKT-介导的OPN和PPARα基因的肝脏表达的机制。拟议的研究将更好地理解乙醇摄入后NKT细胞亚群以激活NKT细胞亚群的关键先天免疫组机制，并应允许鉴定新的免疫靶标在ALD中潜在的治疗干预措施。