Role of IL-37 Genetic Variants in Modulating Innate Immune Resp to Periodontal Pa

IL-37 遗传变异在调节牙周病先天免疫反应中的作用

• 批准号: 8760439
• 负责人: Steven Offenbacher
• 金额: $ 37.75万
• 依托单位: UNIV OF NORTH CAROLINA CHAPEL HILL
• 依托单位国家: 美国
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-08-01 至 2019-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8760439
• 关键词: Acute; Adult; Affect; Agonist; Alveolar Bone Loss; Animal Model; Anti-Inflammatory Agents; Anti-inflammatory; Attenuated; Binding; Biological Markers; CXCL2 gene; Cardiovascular Diseases; Caspase-1; Caucasians; Caucasoid Race; Cell Line; Cells; Cholesterol; Chronic; Clinical; Code; Defect; Diagnosis; Disease; Disease Progression; Disease model; Endotoxins; Exhibits; Genes; Genetic Polymorphism; Genotype; Gingiva; Gingival Crevicular Fluid; Gingivitis; Granulocyte-Macrophage Colony-Stimulating Factor; Homologous Gene; Human; Immune; Immune response; Infection; Inflammation; Inflammation Mediators; Inflammatory; Inflammatory Response; Interferons; Interleukin-1; Interleukin-1 beta; Interleukin-6; MADH3 gene; Measures; Mediating; Mediator of activation protein; Messenger RNA; Microbial Biofilms; Modeling; Mus; Mutation; Natural Immunity; Nature; Odds Ratio; Oral; Oral cavity; Organism; Patients; Periodontal Diseases; Periodontitis; Peripheral Blood Mononuclear Cell; Phenotype; Phosphorylation; Population; Porphyromonas gingivalis; Predisposition; Prevention; Protein Biosynthesis; Proteins; Quantitative Trait Loci; RNA Splicing; Reading; Relative (related person); Reporting; Risk; Role; Site-Directed Mutagenesis; Surface; TNF gene; Testing; Tissues; Transgenic Mice; Variant; Western Blotting; analog; bone loss; cohort; cytokine; genetic variant; genome wide association study; immortalized cell; impaired capacity; improved; indexing; monocyte; novel; oral commensal; peripheral blood; public health relevance; pyrosequencing; research study; response; subcutaneous; trait

DESCRIPTION (provided by applicant): Periodontitis is an inflammatory response to the commensal oral bacterial flora and represents one of the most prevalent infections in humans. Approximately 90% of the population exhibits some form of early disease (gingivitis), with 48% of the US adult population having periodontitis and the severe form of the disease affecting 15-20%. Periodontal disease is a polygenic condition that is associated with an exaggerated inflammatory response to the commensal biofilm that drives chronic biofilm dysbiosis at the biofilm-gingival interface. An elevated level of gingival crevicular fluid (GCF) interleukin 1beta (IL-1¿) has previously been established as a robust biomarker for a hyper- inflammatory phenotype and for mediating severe inflammation, bone loss and periodontal disease progression. We have recently completed a genome-wide association study (GWAS) of 4910 Caucasians with known levels of GCF-IL-1¿ to identify loci that are associated with high levels of GCF-IL-1¿. We have identified two novel quantitative trait loci with missense polymorphisms within the coding region of the anti-inflammatory gene IL37 that are both statistically significanty associated with high GCF-IL-1¿ levels (defined as upper quartile or as a continuous variable), p=6.8 X10-21. These missense polymorphisms at two IL-37 loci, are present in 30% and 8.5% of the population. Not only are both loci strongly associated with high local IL-1¿ levels, but the are also associated with more severe periodontal disease. Under normal conditions IL-37 activates Smad3 and attenuates the innate immune response to TLR agonists to include suppression of IL-1¿, IL-1¿, TNF¿, IL-6, MIP-2 (CXCL2) and GM-CSF. Thus, our central hypothesis is that these IL37 SNP variants cause a functional defect in IL-37 (either via altered mRNA splicing, protein synthesis, activation and/or bioactivity) that results in an excessive pro-inflammatory innate immune response to the commensal organisms of the oral cavity, thereby inducing greater clinical inflammation, bone loss and more severe clinical periodontal disease. Since mice do not express a murine homologue to hIL-37 we propose two aims in murine models to understand whether the two IL37 variants demonstrate impaired IL-37 function I.e. SMAD3 activation and suppression of the innate immune response. First we will transfect murine monocytic RAW cells with the human wild-type [IL37wt] or the two IL37 variants, IL37v1 or IL37v2, to assess the effects of these mutations on IL-37 function, stimulating cells with a range of TLR agonists. These experiments transfecting with IL37v1 or IL37v2 will be confirmed in the human monocytic line THP-1. We expect that the variants will have a hyper-inflammatory trait compared to hIL-37wt, measuring the levels of the mediators listed above, as the read-out. We will also create IL37 variant transgenic mice to measure the response to challenge with P gingivalis using a subcutaneous chamber model and an oral bone loss model. Finally, we will establish a new IL-37 genotyped cohort of subjects to study and confirm the role of these two IL37 variants on IL-37 function and response to TLR challenge using isolated human PBMC and hTERT immortalized cells. It is expected that understanding the role of this novel variant as a potential cause of the underlying hyper-inflammatory trait associated with severe periodontal disease, will ultimately improve diagnosis, prevention and treatment.

描述（由适用提供）：牙周炎是对共生口腔细菌菌群的炎症反应，代表了人类最普遍的感染之一。大约90％的人群表现出某种形式的早期疾病（牙龈炎），其中48％的美国成年人群患有牙周炎，严重的疾病形式影响了15-20％。牙周炎是一种多基因疾病，与对共生生物膜的夸张炎症反应有关，该反应在生物膜和生物膜界面上驱动慢性生物膜营养不良。先前已确定了牙龈裂纹液（GCF）白介素1Beta（IL-1？）的水平升高，是用于过度炎症表型和介导严重感染，骨质流失和牙周疾病进展的强大生物标志物。我们最近完成了4910名高加索人的全基因组关联研究（GWAS），该研究具有已知水平的GCF-IL-1缺水平，以识别与高水平的GCF-IL-1。我们已经确定了两个新型的定量性状基因座，在抗炎基因IL37的编码区域内具有错义多态性，它们在统计学上与高GCF-il-1水平（定义为上四分位数或连续变量），p = 6.8 x10-21具有统计学意义。这些局部两个IL-37的错义多态性存在于30％和8.5％的人口中。局部不仅与局部IL-1水平高密切相关，而且还与更严重的牙周疾病有关。在正常条件下，IL-37激活SMAD3，并减轻对TLR激动剂的先天免疫反应，包括抑制IL-1？，IL-1？，TNF¿，IL-6，IL-6，MIP-2（CXCL2）和GM-CSF。这是我们的中心假设是，这些IL37 SNP变体在IL-37中引起功能缺陷（通过改变的mRNA剪接，蛋白质合成，激活和/或生物活性）导致过量的促炎性的先天性响应，从而对口腔疾病的疾病造成更大的临床疾病损失，从而更高的临床疾病损失，从而更多地造成了临床疾病。由于小鼠没有向HIL-37表达鼠的同源物，因此我们在鼠模型中提出了两个目标，以了解两个IL37变体是否显示出受损的IL-37功能，即，即。 SMAD3激活和抑制先天免疫响应。首先，我们将使用人类野生型[IL37WT]或两个IL37变体IL37V1或IL37V2翻译鼠单核生生细胞，以评估这些突变对IL-37功能的影响，刺激TLR激动剂范围刺激细胞。这些用IL37V1或IL37V2转染的实验将在人类单核细胞系THP-1中得到证实。我们预计，与HIL-37WT相比，这些变体将具有高炎性性状，以读取上面列出的介体的水平。我们还将创建IL37变异转基因小鼠，以使用皮下腔室模型和口服骨质损失模型来测量对P牙龈的反应。最后，我们将建立一个新的IL-37基因分型对象研究，以研究并确认这两种IL37变体在IL-37功能上的作用，并使用分离的人类PBMC和HTERT永生细胞对TLR挑战的反应。可以预期，将这种新型变体理解为与严重牙周疾病相关的潜在高炎性特征的潜在原因，最终将改善诊断，预防和治疗。