Interplay among NKT cell subsets in alcoholic liver disease

酒精性肝病中 NKT 细胞亚群之间的相互作用

• 批准号: 8373146
• 负责人: Vipin Kumar
• 金额: $ 40.5万
• 依托单位: TORREY PINES INST FOR MOLECULAR STUDIES
• 依托单位国家: 美国
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-08-20 至 2017-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8373146
• 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; Injury to Liver; Interleukin-17; Intervention; Ischemia; Knowledge; Lipids; Liquid substance; Liver; Liver diseases; Lymphocyte; Mediating; Metabolic; Modeling; Mus; Myeloid Cells; PTPRC gene; Pathway interactions; Patients; Peroxisome Proliferator-Activated Receptors; Peroxisome Proliferators; Phase; Play; Population; Prevention; Process; Purinergic P1 Receptors; Receptor Gene; Regulatory Pathway; Retinoic Acid Receptor; Role; Small Interfering RNA; Staining method; Stains; Sulfoglycosphingolipids; Therapeutic Intervention; Time; Tissues; Tretinoin; anergy; base; chronic alcohol ingestion; cytokine; feeding; interleukin-23; male; novel; novel therapeutic intervention; osteopontin; pathogen; pre-clinical; prevent; problem drinker; receptor; receptor expression; research study

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, J?18-/- 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-? (PPAR?) 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 ?GalCer/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-? (RAR?) 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 PPAR? 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. PUBLIC HEALTH RELEVANCE: We have identified distinct populations of white blood lymphocytes that accumulate in liver following alcohol consumption in experimental animals. One of them limits liver injury while the other one promotes alcoholic liver disease. This proposal seeks to understand the mechanism by which these lymphocytes control each other and additional disease-causing cells in liver in an effort to develop novel therapeutic approaches for the treatment of alcohol-induced liver damage.

描述（由申请人提供）：本提案旨在了解慢性酒精摄入后导致肝损伤的关键先天免疫机制。细胞间的相互作用 在肝脏中的先天免疫细胞中，包括NKT细胞提供对肠道或代谢抗原的耐受性，同时对病原体的免疫性知之甚少。NKT细胞由两个不同的亚群组成，I型和II型，并识别由CD 1d分子呈递的不同脂质抗原。我们鉴定的II型NKT细胞的主要亚群识别自身糖脂硫苷脂。在两种不同的肝损伤模型中，我们发现，硫苷脂介导的II型NKT细胞活化导致一种新的免疫调节途径的参与，导致I型NKT细胞的无反应性诱导，阻断炎症级联反应，并抑制组织损伤。在此，我们假设NKT细胞亚群的差异激活在肝损伤中起相反的作用，并且它们与其他先天免疫细胞（包括DC和髓样细胞）的相互作用在协调导致ALD的炎症事件中起决定性作用。因此，我们发现，在雄性C57 BL/6小鼠长期加暴食Lieber-DeCarli流质饮食后的ALD临床前阶段，I型而非II型NKT细胞被部分激活，导致炎症细胞募集到肝脏中。一个中心的发现，我们已经取得的是，失活的I型NKT细胞后，管理硫苷脂或全反式维甲酸（ATRA）块ALD。此外，J？I型NKT细胞缺陷的18-/-小鼠被显著保护免于肝损伤。值得注意的是，肝脏基因表达谱显示I型NKT依赖的骨桥蛋白（OPN）的表达，而硫苷脂增强过氧化物酶体增殖物激活受体-？(PPAR?)肝脏水平。细胞表面活化标志物和细胞因子分泌谱的I型和II型NKT细胞亚群在不同阶段的ALD将检查使用？GalCer/CD 1d-和硫苷脂/CD 1d-四聚体，胞浆内染色和流式细胞术。将检查IL-23/IL-17途径和腺苷受体A2 aR在I型NKT细胞活化中的作用。将使用真实的时间PCR和Elisa测定来检查乙醇喂养后临床前和临床阶段期间肝脏中其他先天性细胞的活化。将分别研究NKT细胞活化和ALD中常规cDC或CD 11b +Gr-1+细胞的连续转移实验或耗竭。将研究ATRA或硫苷脂抑制I型激活导致肝损伤阻断的机制。硫苷脂、全反式维甲酸、视黄酸 受体-？(RAR?)或它们与其它抑制性细胞因子的组合沿着将用于有效治疗正在进行的肝病。NKT介导OPN和PPAR在肝脏表达的机制？将使用siRNA和基因缺陷动物检查人类和实验ALD中共有的基因。拟议的研究将提供一个更好的了解关键的先天免疫机制集中在激活NKT细胞亚群后，乙醇摄入，并应允许识别新的免疫靶点的ALD的潜在治疗干预。 公共卫生关系：我们已经确定了不同的群体的白色血液淋巴细胞，积累在肝脏酒精消费后，在实验动物。其中一种限制肝损伤，而另一种促进酒精性肝病。该提案旨在了解这些淋巴细胞相互控制和肝脏中其他致病细胞的机制，以努力开发治疗酒精诱导的肝损伤的新治疗方法。