Kynurenine-dependent redox signaling at the interface between innate and adaptive immunity

先天免疫和适应性免疫之间界面的犬尿氨酸依赖性氧化还原信号传导

• 批准号: 10749210
• 负责人: Dario A Vitturi
• 金额: $ 56.43万
• 依托单位: UNIVERSITY OF ALABAMA AT BIRMINGHAM
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-07-19 至 2028-06-30
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10749210
• 关键词: Acute; Address; Ally; Anti-Inflammatory Agents; Antigen-Presenting Cells; Aryl Hydrocarbon Receptor; Attenuated; Autoimmune Diseases; Autoimmunity; Biological Assay; Cells; Chronic; Cysteine; Cytoprotection; Data; Dendritic Cells; Development; Endotoxemia; Endotoxins; Energy Metabolism; Exposure to; Fostering; Foundations; Generations; Genes; Genetic Transcription; Goals; Graft Rejection; Health; Hepatocyte; Human; Immune; Immune Tolerance; Immune response; Inflammasome; Inflammation; Inflammatory; Inflammatory Response; Intervention; Isotopes; Kinetics; Knowledge; Kynurenine; Label; Leukocytes; Life; Ligands; Link; Liver; Macrophage; Malignant Neoplasms; Mediating; Mediator; Metabolic; Metabolism; Mission; Mitochondria; Modeling; Molecular; Mus; Myelogenous; Myeloid Cell Activation; Natural Immunity; Organ Transplantation; Outcome; Oxidation-Reduction; Pathway interactions; Phenotype; Public Health; Publishing; Reaction; Receptor Signaling; Regulation; Regulatory T-Lymphocyte; Reporting; Research; Resistance; Respiration; Role; Secondary to; Sepsis; Signal Pathway; Signal Transduction; Solid; Sulfhydryl Compounds; Supplementation; T cell differentiation; T-Lymphocyte; TLR4 gene; Testing; Toll-like receptors; Tryptophan; Tryptophan Metabolism Pathway; Tryptophanase; United States National Institutes of Health; Up-Regulation; Work; adaptive immunity; allograft rejection; chemical synthesis; design; disability; extracellular; immune activation; immunoregulation; in vivo; indoleamine; insight; knockout animal; metabolomics; novel; novel therapeutics; pharmacologic; polarized cell; programs; response; systemic inflammatory response; uptake

The kynurenine pathway catabolizes over 95% of all tryptophan primarily through the actions of tryptophan 2,3-dioxygenase 2 (TDO2) in hepatocytes and indoleamine 2,3-dioxygenese 1 (IDO1) in myeloid leukocytes. Increased kynurenine synthesis in dendritic cells (DC) secondary to IDO1 upregulation is strongly linked with the generation of a tolerogenic phenotype by promoting anti-inflammatory signaling, regulatory T cell (Treg) polarization and immune tolerance, an attenuated inflammatory response instigated by immune cells that are repeatedly exposed to TLR ligands. However, while the pathophysiologic relevance of this pathway is well- established, the mechanism behind the immunomodulatory effects of kynurenine remain poorly defined. Using semi-targeted metabolomic approaches, we recently published that systemic increases in kynurenine levels secondary to either exogenous supplementation or chronic inflammation are associated with the formation of the novel cysteine-reactive kynurenine-derived electrophile Kyn-CKA. Kyn-CKA promotes Nrf2-depedent signaling, inhibits TLR4-dependent NF-κB pathways and attenuates inflammatory responses in endotoxin-challenged mice in a redox-dependent manner. In addition, Kyn-CKA engages AhR signaling with 20-fold higher potency than its kynurenine precursor, suggesting a potential pro-tolerogenic role in DC and T-cells. Specifically designed state- of-the-art LC-MS/MS assays will enable the quantification of Kyn-CKA in the context of other kynurenine pathway metabolites in activated and non-activated myeloid leukocytes, as well as the elucidation of rate-limiting cellular uptake and export mechanisms. Primary macrophages, dendritic, and T cells derived from pathway-specific knock-out animals will be harnessed in conjunction with novel bio-orthogonal labeling strategies and isotope- tracing metabolic flux analyses to define the mechanistic basis of the anti-inflammatory actions of Kyn-CKA both in terms of the modulation of specific signaling pathways and its effects on inflammation-elicited changes in energy metabolism. The ability of Kyn-CKA to promote tolerogenic responses will be established by assessing its effect on the maturation and activation of conventional DC subpopulations, its impact on T cell polarization, and its ability to modulate endotoxin resistance and tolerance in vivo. Mice expressing or lacking critical mediators of Kyn-CKA formation and action in cell-specific compartments will be used to obtain mechanistic insights in vivo. In summary, the Research Plan addresses a hitherto unappreciated redox-dependent component of the immunomodulatory actions of the kynurenine pathway, mediated by the formation of electrophilic Kyn-CKA. If successful, our work will enable the potential development of novel Kyn-CKA based pharmacological interventions for dysregulated immune responses such as chronic inflammation, autoimmune diseases, cancer, and allograft rejection.

Kynurenine途径通过通过 色氨酸2,3-二氧酶2（TDO2）中的肝细胞和吲哚胺2,3-二氧酶1（IDO1） 白细胞。 IDO1上调的树突状细胞（DC）中的Kynurenine合成增加非常强烈 通过促进抗炎信号传导，调节性T细胞与耐受性表型的产生有关 （TREG）极化和免疫耐受性，这是免疫细胞刺激的炎症反应， 反复暴露于TLR配体。但是，尽管该途径的病理生理相关性是很好的 既定的，kynurenine的免疫调节作用背后的机制仍然很差。使用 半靶向代谢组学方法，我们最近发表了kynurenine水平的系统性增加 继发于外源补充或慢性炎症与形成有关 新型半胱氨酸反应性kynurenine衍生的电力kyn-cka。 kyn-cka促进NRF2-Depedent信号传导， 抑制TLR4依赖性NF-κB途径，并减弱内毒素挑战小鼠的炎症反应 以氧化还原依赖的方式。此外，Kyn-CKA与AHR信号的效力高20倍 Kynurenine前体，表明在DC和T细胞中具有潜在的亲同学作用。专门设计的状态 - ART LC-MS/MS分析将使Kyn-CKA在其他Kynurenine途径中进行定量 活化和未激活的髓样白细胞中的代谢产物，以及阐明速率的细胞 吸收和出口机制。衍生自途径特异性的一级巨噬细胞，树突状和T细胞 敲除动物将与新型的生物正交标记策略和同位素一起利用。 追踪代谢通量分析以定义Kyn-CKA抗炎作用的机理基础 关于特定信号通路的调节及其对炎症引起的变化的影响 能量代谢。 Kyn-CKA促进耐受反应的能力将通过评估来确定 它对常规直流亚群的成熟和激活的影响，其对T细胞极化的影响， 以及它在体内调节内毒素耐药性和耐受性的能力。表达或缺乏关键的小鼠 Kyn-CKA形成和动作在细胞特异性室中的介体将用于获得机械 体内见解。总而言之，研究计划涉及一个隐藏的未批准的氧化还原依赖性的 Kynurenine途径的免疫调节作用的成分，由形成 亲电kyn-cka。如果成功，我们的工作将使基于Kyn-CKA的新型发展具有潜在的发展 免疫复杂失调的药理干预措施，例如慢性感染，自身免疫性 疾病，癌症和同种异体移植排斥。