Regulation of Innate Immune Signaling by Lyn Kinase

Lyn 激酶对先天免疫信号的调节

基本信息

批准号：
8997442
负责人：
Clifford A Lowell
金额：
$ 39.63万
依托单位：
UNIVERSITY OF CALIFORNIA, SAN FRANCISCO
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：
2015-02-01 至 2020-01-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8997442
关键词：
Address Affect Allergic Animal Testing Animals Anti-Bacterial Agents Anti-Inflammatory Agents Anti-inflammatory Antibody Formation Area Autoimmune Diseases Autoimmune Process Autoimmunity B-Lymphocytes BCL10 gene Biochemical Biochemical Genetics C Type Lectin Receptors C-Type Lectins Cells Collaborations Complex Data Defect Dendritic Cells Development Diabetes Mellitus Disease Enzymes Functional disorder Generations Genetic Goals Health Hematopoietic Human Hyperactive behavior ITGAX gene Immune Immune Cell Activation Immune Complex Glomerulonephritis Immune Tolerance Immune response Immunity Immunoglobulin G Immunoglobulin M In Vitro Infection Inflammation Inflammatory Interleukin-1 Intestines Investigation Knock-out Lead Lupus Lymphocyte Lymphocyte Subset Lymphoid Mediating Methods Modeling Molecular Mouse Strains Mus Mutant Strains Mice Mutation Myeloid Cells Onset of illness Organism Pathogenesis Pathway interactions Patients Permeability Phenotype Phosphotransferases Play Process Production Protein Tyrosine Kinase Protein Tyrosine Phosphatase Proteins Recruitment Activity Regulation Role Series Signal Pathway Signal Transduction Stromal Cells Supplementation T-Lymphocyte Testing Therapeutic Trials Tissues Work cell type chemical genetics cytokine disease phenotype genetic approach gut microbiota lupus-like lymph nodes microbiome microbiota mortality mouse model mutant novel protein complex receptor research study therapeutic target

项目摘要

DESCRIPTION (provided by applicant): There is a growing recognition that innate immune cells play a critical role in initiating and sustaining autoimmune and inflammatory disorders. The Lyn tyrosine kinase is one of the primary inhibitory enzymes that regulate innate immune cell signaling. Lyn functions by phosphorylating inhibitory receptors that recruit tyrosine phosphatases to down modulate cellular activation. In the absence of Lyn kinase, mice develop spontaneous autoimmunity resembling human systemic lupus erythematous (SLE). In preliminary studies, we have found that loss of Lyn kinase in dendritic cells (DCs) alone is sufficient to cause a severe autoimmune/inflammatory disease, with strong tissue inflammation and reduced survival, compared to the global lyn-/- mice. This disease is completely dependent on MyD88-signaling, since generation of mice lacking MyD88 and Lyn in DCs alone lack the inflammation and autoimmunity. These observations provide a clear example that mutations resulting in loss of inhibitory signaling in DCs can result in breakdown of immune tolerance in lymphocytes, leading to autoimmunity. This proposal consists of 4 specific aims. Our first aim is to define the molecular mechanisms by which inhibition of tyrosine kinase pathways impacts MyD88 signaling in DCs. We hypothesize that the cross talk between these pathways occurs via the CARD9/Malt1/Bcl10 complex, which we will investigate biochemically and genetically. We will use a chemical genetic approach to define the molecular substrates of Lyn in DCs. Aim #2 will expand on our preliminary observations, done with Dr. Lynch (UCSF) that loss of Lyn in DCs results in dysbiosis of gut microbiota, allowing for outgrowth of species that may drive systemic inflammation by altering the intestinal barrier function. We will expand on these observations in a series of microbiota profiling experiments, by use of bacterial supplementation methods, and by directly examining intestinal barrier function in the various Lyn-deficient strains. Aim #3 will expand on preliminary data suggesting that an undefined Lyn-mediated signaling pathway in non- hematopoietic cells may have an immunomodulatory effect on the disease process in lyn-/- mice. Lyn related inhibitory signaling in non-hematopoietic cells is very poorly studied. We will focus on follicular retricular cells using biochemical and genetic means (including generating mutant mice lacking Lyn in these cells specifically). Aim #4 will expand on preliminary studies done with Dr. Locksley (UCSF) showing that group 2 innate lymphocytes (ILC2s) are expanded and activated in lyn-/- mice. This aim will address whether altered signaling in ILC2 cells alone can lead to spontaneous disease phenotypes (by generating novel ILC2-specific lyn mutants) and whether these cells may contribute to autoimmune disease. Since changes in Lyn kinase related signaling pathways have been observed in human SLE patients and Lyn is now a therapeutic target in diabetes treatments (therapeutic trials) understanding the inhibitory signaling pathways regulated by this kinase in innate cells will have direct impact on human autoimmune and inflammatory conditions.

描述（由适用提供）：越来越多的认识是，先天免疫细胞细胞在发起和维持自身免疫性和炎症性疾病中起着至关重要的作用。 lyn酪氨酸激酶是调节先天免疫球信号传导的主要抑制酶之一。 LYN通过磷酸化受体的磷酸化受体起作用，从而募集酪氨酸磷酸酶调节细胞活化。在没有Lyn激酶的情况下，小鼠会形成赞助商供电的自身免疫性，类似于人类的狼疮红斑（SLE）。在初步研究中，我们发现与全球LYN - / - 小鼠相比，单独的树突状细胞（DC）中Lyn激酶的丧失足以引起严重的自身免疫/炎症性疾病，具有强大的组织感染和降低的存活率。这种疾病完全取决于MyD88信号，因为仅在DC中缺乏MyD88和Lyn的小鼠缺乏炎症和自身免疫性。这些观察结果清楚地表明，导致DC中抑制性信号传导丧失的突变会导致淋巴细胞中免疫耐受性的分解，从而导致自身免疫性。该提案包括4个具体目标。我们的第一个目的是定义抑制酪氨酸激酶途径的分子机制，影响DC中的MYD88信号传导。我们假设这些途径之间的交叉说话是通过Card9/Malt1/Bcl10复合物发生的，我们将在生化和遗传上研究。我们将使用一种化学遗传方法来定义DC中LYN的分子底物。 AIM＃2将通过Lynch博士（UCSF）进行的初步观察扩展，DCS中Lyn的损失会导致肠道菌群的失调，从而使可能通过改变肠道屏障功能来驱动系统感染的物种的生长。我们将在一系列微生物群分析实验中，使用细菌补充方法以及直接检查各种Lyn缺陷菌株中的肠道屏障功能来扩展这些观察结果。 AIM＃3 Will 扩展了初步数据，表明非脊髓细胞中未定义的LYN介导的信号传导途径可能对LYN - / - 小鼠的疾病过程有免疫调节作用。 LYN与非脊髓性细胞中相关的抑制性信号传导非常差。我们将使用生化和遗传手段（包括在这些细胞中缺乏LYN的突变小鼠）专注于卵泡式循环细胞。 AIM＃4将扩大对Locksley博士（UCSF）进行的初步研究，表明第2组先天淋巴细胞（ILC2）在Lyn - / - 小鼠中被扩展和激活。这个目的将解决单独的ILC2细胞中的信号传导是否会导致赞助疾病表型（通过产生新型的ILC2特异性LYN突变体）以及这些细胞是否可能导致自身免疫性疾病。由于已经在人类SLE患者中观察到LYN激酶相关信号通路的变化，而LYN现在是糖尿病治疗（治疗试验）的治疗靶标（治疗试验），理解由这种先天细胞中该激酶调节的抑制性信号传导途径将直接影响人类自身免疫性和炎症条件。