Effector function of natural killer T (NKT) cells in sarcoidosis

结节病中自然杀伤 T (NKT) 细胞的效应功能

• 批准号: 7660211
• 负责人: LAURA L KOTH
• 金额: $ 7.73万
• 依托单位: UNIVERSITY OF CALIFORNIA, SAN FRANCISCO
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-04-15 至 2011-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7660211
• 关键词: Address; Adrenal Cortex Hormones; Age; Area; Autoantigens; Autoimmune Diseases; Biology; Blood; Bronchoalveolar Lavage; Cell physiology; Cells; Characteristics; Chronic; Clinical; Clinical Research; Clinical Trials; Color; Coughing; Cross-Sectional Studies; Data; Development; Disease; Dyspnea; Educational workshop; Effector Cell; Equilibrium; Etiology; Flow Cytometry; Funding; Future; Goals; Health; Human; Immune; Immune response; Immunology; Immunosuppression; Immunosuppressive Agents; In Vitro; Individual; Inflammatory; Interferon Type II; Interferons; Interleukin-13; Interleukin-4; Knowledge; Lead; Life; Ligands; Longitudinal Studies; Lung; Lung diseases; Malignant Neoplasms; Measurement; Measures; Methods; Methotrexate; Mus; National Heart, Lung, and Blood Institute; Organ; Pathogenesis; Patients; Peripheral Blood Mononuclear Cell; Phase; Phenotype; Pilot Projects; Play; Population; Production; Pulmonary Sarcoidosis; Race; Research; Role; Sarcoidosis; Severities; Severity of illness; Staging; Stimulus; Symptoms; T-Lymphocyte; T-Lymphocyte Subsets; Testing; Thoracic Radiography; Toxic effect; Translating; United States National Institutes of Health; base; cell type; cytokine; disease phenotype; drug development; efficacy testing; follow-up; healthy volunteer; improved; killer T cell; novel; peripheral blood; prevent; public health relevance; response; sex; treatment strategy; volunteer

DESCRIPTION (provided by applicant): Sarcoidosis is a systemic inflammatory disease of unknown etiology and has no cure. It is thought to be caused by an abnormal immune response to either a self or non-self antigen. Sarcoidosis is characterized by a Th1 immune response with interferon-gamma being the predominant cytokine. Despite this knowledge, little is known about the regulators of this aberrant immune response, and current treatment approaches (e.g. systemic corticosteroids and methotrexate) are non-specific and have significant toxicities. Natural killer T (NKT) cells are immunoregulatory T cells that can either promote or suppress immune responses depending on local stimuli. In mice, NKT cells have been found to be protective in several autoimmune diseases. In humans, two independent clinical studies found that the numbers of peripheral blood and lung NKT cells were significantly lower in patients with pulmonary sarcoidosis compared to controls. Thus, NKT cells are abnormally regulated in sarcoidosis. However, large gaps in knowledge exist about the cellular subsets and effector function of NKT cells in this disease. Specific Aims. Because a deficiency of the CD4+ subset of NKT cells may skew immune responses towards Th1 responses (a characteristic of sarcoidosis), we hypothesize that the overall NKT cell deficiency in sarcoidosis is due to a selective loss of the CD4+ NKT cell subset leading to a paucity of Th2 cytokines and a skewing of the cytokine balance in favor of Th1 cytokine-producing CD4- NKT cells. Therefore, we will 1) determine the distribution of CD4+ vs. CD4- NKT cells in sarcoidosis and their cytokine responses after stimulation with CD1d ligands in a cross-sectional study and 2) determine how NKT cell effector function relates to disease severity, progression and phenotype in sarcoidosis subjects and the effect of immune- suppression on NKT cell subsets and cytokine responses in a longitudinal study. Experimental Approach: We will collect peripheral blood mononuclear cells from normal volunteers and subjects with sarcoidosis. Directly ex-vivo we will determine the number of CD4+ and CD4- NKT cells and their cytokine responses to several NKT cell ligands using novel in vitro stimulation methods and multi-color flow cytometric analysis. These responses will be compared to those from matched healthy volunteers. We will also analyze NKT cell subsets and cytokine responses within sarcoidosis subjects longitudinally at ~6 month intervals and correlate these measurements to disease severity. Additionally, we will determine the effect of systemic immunosuppressants on NKT cell subsets and cytokine responses. Finally, we will compare blood and lung NKT cell effector function in a pilot study of 5-10 pulmonary sarcoidosis subjects. Significance of the results. Since NKT cells may play a role in the pathogenesis of sarcoidosis, findings from this study could identify a new cell type that may be targeted in novel treatment strategies using CD1d ligands, which was identified as a major priority area of research in sarcoidosis by a recent NHLBI workshop. PUBLIC HEALTH RELEVANCE: The scientific aims of the clinical project for which we are seeking support from the NIH is to comprehensively analyze the function of a recently identified immunoregulatory cell, the natural killer T cell, in patients with sarcoidosis. One of the overriding goals of this project is to advance the knowledge of the immunology of sarcoidosis so that this may be translated into more specific therapies to reduce suffering of patients and thereby promote lung health and improve patients' lives. In addition, by achieving a better understanding of the immunology of sarcoidosis, we may be able to prevent this lung disease.

描述（由申请人提供）：结节病是一种病因不明的全身性炎症性疾病，目前尚无治愈方法。它被认为是由对自体或非自体抗原的异常免疫反应引起的。结节病的特点是Th1免疫应答，干扰素是主要的细胞因子。尽管有这些知识，但对这种异常免疫反应的调节因子知之甚少，目前的治疗方法（如全身皮质类固醇和甲氨蝶呤）是非特异性的，并且具有显著的毒性。自然杀伤T细胞（NKT）是免疫调节性T细胞，可以根据局部刺激促进或抑制免疫反应。在小鼠中，已发现NKT细胞对几种自身免疫性疾病具有保护作用。在人类中，两项独立的临床研究发现，与对照组相比，肺结节病患者外周血和肺NKT细胞的数量明显较低。因此，NKT细胞在结节病中受到异常调节。然而，关于NKT细胞在该疾病中的细胞亚群和效应功能存在很大的知识空白。具体的目标。由于NKT细胞CD4+亚群的缺乏可能使免疫反应偏向Th1反应（结节病的一个特征），我们假设结节病中NKT细胞的总体缺乏是由于CD4+ NKT细胞亚群的选择性缺失导致Th2细胞因子的缺乏和细胞因子平衡的倾斜，从而有利于产生Th1细胞因子的CD4- NKT细胞。因此，我们将在横断面研究中确定CD4+和CD4- NKT细胞在结节病中的分布以及CD1d配体刺激后的细胞因子反应；在纵向研究中确定NKT细胞效应物功能与结节病患者疾病严重程度、进展和表型的关系，以及免疫抑制对NKT细胞亚群和细胞因子反应的影响。实验方法：采集正常志愿者和结节病患者外周血单个核细胞。直接离体，我们将使用新的体外刺激方法和多色流式细胞术分析确定CD4+和CD4- NKT细胞的数量及其对几种NKT细胞配体的细胞因子反应。这些反应将与匹配的健康志愿者的反应进行比较。我们还将以6个月为间隔纵向分析结节病患者的NKT细胞亚群和细胞因子反应，并将这些测量结果与疾病严重程度相关联。此外，我们将确定全身免疫抑制剂对NKT细胞亚群和细胞因子反应的影响。最后，我们将在5-10名肺结节病受试者的初步研究中比较血液和肺NKT细胞效应功能。结果的意义。由于NKT细胞可能在结节病的发病机制中发挥作用，本研究的发现可以鉴定出一种新的细胞类型，这种细胞类型可能成为使用CD1d配体的新治疗策略的靶点，这是最近NHLBI研讨会确定的结节病研究的主要优先领域。公共卫生相关性：我们正在寻求美国国立卫生研究院支持的临床项目的科学目标是全面分析最近发现的免疫调节细胞，自然杀伤T细胞在结节病患者中的功能。该项目的首要目标之一是提高对结节病免疫学的认识，以便将其转化为更具体的治疗方法，以减少患者的痛苦，从而促进肺部健康，改善患者的生活。此外，通过更好地了解结节病的免疫学，我们可能能够预防这种肺部疾病。