Liver Kinase B1, a genetic risk factor for multiple sclerosis

肝激酶 B1，多发性硬化症的遗传危险因素

• 批准号: 10427134
• 负责人: Douglas L. Feinstein
• 金额: --
• 依托单位: JESSE BROWN VA MEDICAL CENTER
• 依托单位国家: 美国
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-01-01 至 2023-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10427134
• 关键词: Address; African American; Anti-Inflammatory Agents; Astrocytes; Benign; Binding; Brain; Caucasians; Cell Polarity; Cells; Clinical; Code; DNA; Development; Diagnosis; Disease; Disease Progression; Energy Supply; Environment; Experimental Autoimmune Encephalomyelitis; Family; Family member; Generations; Genes; Genetic Polymorphism; Genotype; Growth; High Prevalence; Human; IgG Receptors; Immune response; Immunoglobulin G; Immunoglobulins; Impairment; Inflammatory Response; Introns; Knock-out; Knockout Mice; Knowledge; LCN2 gene; Maintenance; Messenger RNA; Metabolic; Metabolism; Methods; Microglia; Mitochondria; Motor Neurons; Multiple Sclerosis; Mus; Mutation; Neuroglia; Neurons; Nitrogen; Nucleotides; Odds Ratio; Oligodendroglia; Ovarian Cysts; Oxygen; Parents; Pathway interactions; Patients; Peripheral Blood Mononuclear Cell; Peutz-Jeghers Syndrome; Phenotype; Phosphotransferases; Play; Poison; Production; Property; Protein-Serine-Threonine Kinases; Proteins; Rare Diseases; Relapse; Role; STK11 gene; Sampling; Schwann Cells; Serum; Siblings; Single Nucleotide Polymorphism; Spinal Cord; Syndrome; Testing; Therapeutic Intervention; Transcript; Tumor Suppressor Genes; Tumor Suppressor Proteins; Variant; Veterans; associated symptom; base; caucasian American; cell growth regulation; cohort; comorbidity; conditional knockout; cytokine; energy balance; experimental study; genetic risk factor; genome wide association study; inflammatory milieu; knock-down; liver function; migration; monocyte; multiple sclerosis patient; myelination; neuroinflammation; neurotoxic; new therapeutic target; novel; peripheral blood; rare cancer; recruit; response; sensor; transcriptome sequencing; tumor; virtual

During the course of recruiting MS patients for a study of PBMCs, a family with 5 siblings diagnosed with MS was identified. The presence of a co-morbidity for certain rare tumors led to sequencing analysis of tumor suppressor gene STK11, and a variant (small nucleotide polymorphism, SNP) was identified. Genotyping of a large number of DNA samples showed that this SNP is present at higher levels in MS patients in both Caucasian and African American cohorts. STK11 codes for the Liver kinase B1 (LKB1) which has roles in regulation of cellular metabolism and inflammatory responses in Tcells, glial cells, and oligodendrocytes. Since the role of LKB1 in MS has not been characterized, and since brain astrocytes play an important role in maintaining energy balance and restricting immune responses, we hypothesized that reducing astrocyte LKB1 expression or activity would worsen EAE. Our findings using mice with LKB1 knocked out from astrocytes (“cKO mice”) confirmed this hypothesis and identified pathways that are altered in the astrocyte deficient mice and cells. In this project, we will determine how LKB1 deficiency in astrocyte effects their metabolic properties (mitochondrial function, and production of lactate which can be provided to neurons on demand). We will test the effects of the media prepared from the astrocytes (“Conditioned media”, CM) on microglial cells to see if microglial cell activation is increased. We will add astrocyte CM to naïve Tcells to see if the CM converts them into a damaging phenotype (Th1 or Th17; cells that produce toxic substances during EAE and MS). We will test effects of the CM on neurons, to see if the astrocytes produce neurotoxic substances; and add CM to oligodendrocytes to see if maturation is reduced. In our studies, we found that one of the proteins most increased in astrocyte cKO mice was lipocalin 2 (LCN2), a protein involved in inflammatory responses in other diseases, and highly expressed in astrocytes. However, roles for astrocyte LCN2 in EAE are not well known. We will generate new mice where astrocyte LCN2 is knocked down, to see if that reduces EAE disease. We also found that in astrocyte LKB1 cKO mice, there was extensive damage occurring to motor neurons in the spinal cord, which could contribute to weakness in MS patients. The cause of that damage is unknown, however findings that there is a large accumulation of immunoglobulins in those neurons suggests that these cells have increased expression of an IgG receptor. Experiments to test this are proposed. Finally, while our studies are using conditional knockout of LKB1 from cells, we do not know if the STK11 SNP, which does not cause knockout but alters LKB1 levels, has the same effect. To address this, we will use a novel method to generate microglial cells from human peripheral blood monocytes. Although microglia differ from astrocytes, we will be able to compare the responses of microglia with the normal, wildtype STK11 gene to those having the STK11 SNP. Overall, these studies will expand our knowledge of how LKB1 regulates the development of MS and EAE, and identify new targets for therapeutic interventions in MS patients who have deficiencies in LKB1 expression.

在招募MS患者进行PBMC的过程中，一个有5个兄弟姐妹诊断的家庭 使用MS。某些稀有肿瘤的共生率的存在导致测序 肿瘤抑制基因STK11和变体（小核苷酸多态性，SNP）的分析为 确定。大量DNA样品的基因分型表明，该SNP存在于较高 高加索和非裔美国人队列的MS患者的水平。 STK11肝脏代码 激酶B1（LKB1）在调节细胞代谢和炎症反应中具有作用 TCELLS，神经胶质细胞和少突胶质细胞。由于尚未表征LKB1在MS中的作用，因此 而且由于大脑星形胶质细胞在维持能量平衡和限制中起着重要作用 免疫反应，我们假设减少星形胶质细胞LKB1表达或活性 恶化。我们使用LKB1的小鼠从星形胶质细胞（“ CKO小鼠”）敲出来的发现证实了我们的发现 该假设并鉴定出在星形胶质细胞不足的小鼠和细胞中改变的途径。 在这个项目中，我们将确定星形胶质细胞中LKB1缺乏症如何影响其代谢特性 （线粒体功能和可按需提供给神经元的鞋底的产生）。我们 将测试由星形胶质细胞（“条件介质”，CM）制备的介质对小胶质细胞的影响 细胞以查看小胶质细胞活化是否增加。我们将在天真的tcells中添加星形胶质细胞CM，以查看是否是否 CM将它们转换为有害的表型（Th1或Th17；产生有毒物质的细胞 在EAE和MS期间）。我们将测试CM对神经元的影响，以查看星形胶质细胞是否产生 神经毒性物质；并将CM添加到少突胶质细胞中，以查看是否降低成熟。 在我们的研究中，我们发现星形胶质细胞CKO小鼠中最大升高的蛋白质之一是Lipocalin 2 （LCN2），一种参与其他疾病中炎症反应的蛋白质，在 星形胶质细胞。然而，EAE中星形胶质细胞LCN2的角色尚不清楚。我们将生成新的老鼠 在撞倒星形胶质细胞LCN2的地方，看看这是否减少了EAE疾病。我们还发现 星形胶质细胞LKB1 CKO小鼠，脊柱中的运动神经元造成了广泛的损害 绳索，这可能导致MS患者的弱点。造成这种伤害的原因是未知的， 但是发现这些神经元中的免疫球蛋白大量积累表明 这些细胞的表达增加了IgG受体。提出了对此进行测试的实验。 最后，虽然我们的研究正在使用细胞的有条件敲除lkb1的条件敲除，但我们不知道是否是否 STK11 SNP不会引起敲除，而是改变LKB1水平，具有相同的效果。解决 这，我们将使用一种新颖的方法来产生来自人类外周血单核细胞的小胶质细胞。 尽管小胶质细胞与星形胶质细胞不同，但我们将能够将小胶质细胞的反应与 具有STK11 SNP的正常的野生型STK11基因。 总体而言，这些研究将扩大我们对LKB1如何调节MS和MS发展的了解 EAE，并确定对缺乏症状的MS患者进行治疗干预措施的新目标 LKB1表达。