Controlling the flux of sphingosine-1-phosphate in vivo

控制体内 1-磷酸鞘氨醇的通量

基本信息

批准号：
10319600
负责人：
KEVIN R. LYNCH
金额：
$ 68.95万
依托单位：
UNIVERSITY OF VIRGINIA
依托单位国家：
美国
项目类别：
财政年份：
2019
资助国家：
美国
起止时间：
2019-01-15 至 2023-12-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10319600
关键词：
Acute Acute Renal Failure with Renal Papillary Necrosis Adverse event Affect Agonist Animal Model Autoimmune Diseases Biological Biological Assay Biological Availability Biological Testing Biology Blood Blood Vessels Bradycardia Cardiac Cells Chemicals Chronic Kidney Failure Clinic Clinical Clinical Trials Complex Coupled Cytoplasm Data Disease model Dose Drug Kinetics Drug Targeting Endothelial Cells Endothelium Environment Enzymes Erythrocytes Experimental Autoimmune Encephalomyelitis Generations Genetic study Goals Immune Immune System Diseases Immune response Immune system Immunomodulators Immunooncology Immunosuppressive Agents Inorganic Phosphate Transporter Lead Leukocytes Lipids Lymph Lymphocyte Lymphocyte Count Lymphoid Tissue Lymphopenia Masks Medicine Methods Modeling Modification Multiple Sclerosis Mus Mutant Strains Mice Oral Pathway interactions Peripheral Blood Lymphocyte Pharmaceutical Preparations Pharmacodynamics Pharmacology Phosphorylation Physiological Plasma Positioning Attribute Process Property Proteins Reperfusion Injury Role SPHK1 enzyme Saccharomyces cerevisiae Saccharomycetales Second Messenger Systems Series Signal Transduction Signaling Molecule Sphingosine Sphingosine-1-Phosphate Receptor Testing Therapeutic Therapeutic Agents Thymus Gland Tissues Toxic effect Treatment Efficacy Validation base cell motility chemical synthesis desensitization edg-1 Protein extracellular genetic manipulation immune system function immunoregulation in vivo inhibitor kinase inhibitor lymph nodes lymphocyte trafficking meetings melanoma migration multiple sclerosis treatment ototoxicity pre-clinical programs renal ischemia screening side effect small molecule libraries sphingosine 1-phosphate sphingosine kinase success targeted agent targeted biomarker therapeutic target tool transport inhibitor

项目摘要

Sphingosine 1-phosphate (S1P) chemotactic gradients are necessary for correct temporal and spatial positioning of immune cells while the blood-tissue S1P gradient supports endothelial barrier integrity. We propose now to provide a new method of modulating the immune system by changing the lymph-lymph node S1P gradient, which is crucial for lymphocyte trafficking. The initial indication that S1P gradients have a pivotal role in immune cell migration was the discovery of the mechanism of action of the immunosuppressive drug, fingolimod. This drug desensitizes lymphocyte S1P1 receptors, which renders these cells unable to migrate from secondary lymphoid tissues to the S1P rich environment of efferent lymph. Although ultimately successful as a medicine, fingolimod and other S1P1 receptor agonists have on-target cardiac and vascular toxicities, which necessitates additional strategies to modulate the immune response by manipulating S1P signaling. Studies with mutant mice predict that a viable alternative strategy is to eliminate the lymph-lymph node S1P gradient by inhibiting the transporter, Spns2, which supplies S1P from endothelial cells to efferent lymph. However, the Spns2 inhibitors that are required to test this idea are not available. As a first step in meeting this need, we took advantage of the toxicity of high levels of S1P in Saccharomyces cerevisiae to build an S1P transporter assay. We used this assay to screen our focused chemical library of S1P agonists and sphingosine kinase inhibitors and identified a hit compound that, after minimal chemical manipulation, resulted in a lead compound that drives the lymphopenia and reduction in plasma S1P expected of an Spns2 inhibitor. Through iterative chemical synthesis and pharmacologic testing, we will optimize our lead Spns2 inhibitor as well as discover and optimize additional chemical series of Spns2 inhibitors. Ultimately, we will generate potent Spns2 inhibitors with the pharmacokinetic properties suitable for in vivo applications. The selectivity of the Spns2 inhibitors will be ascertained by rigorous counter-screening against other S1P interacting proteins including S1P receptors, catabolic and anabolic enzymes and another, erythrocyte-specific, S1P transporter, Mfsd2b. In developing Spns2 inhibitors, we will use plasma S1P levels and peripheral blood lymphocyte counts as biomarkers of target engagement. Spns2 inhibitors will be deployed in a battery of disease models where immune-modulation is indicated. Further, we will assess our Spns2 inhibitors for potential adverse events associated with S1P signaling including vascular leak, bradycardia and ototoxicity. Optimally, our studies will validate Spns2 as a therapeutic target for immune system modulation. At a minimum, we will provide reliable chemical tool for exploring the complex biology of S1P.

1-磷酸盐（S1P）趋化梯度对于正确的时间和空间定位是必要的，而血液组织S1P梯度支持内皮屏障完整性。我们现在建议通过改变淋巴结节点S1P梯度来提供一种新方法来调节免疫系统，这对于淋巴细胞运输至关重要。最初的迹象表明，S1P梯度在免疫细胞迁移中具有关键作用是发现免疫抑制药物Fingolimod的作用机理。这种药物使淋巴细胞S1P1受体脱敏，这使这些细胞无法从继发性淋巴组织迁移到富含S1P的淋巴环境。尽管最终作为药物成功，但Fingolimod和其他S1P1受体激动剂具有靶向心脏和血管毒性，这需要其他策略来通过操纵S1P信号传导来调节免疫反应。使用突变小鼠的研究预测，可行的替代策略是通过抑制转运蛋白SPNS2来消除淋巴结节点S1P梯度，该转运蛋白SPNS2从内皮细胞中提供S1P到淋巴。但是，无法使用该想法所需的SPNS2抑制剂。作为满足这一需求的第一步，我们利用了酿酒酵母中高水平的S1P毒性来构建S1P转运蛋白分析。我们使用该测定法筛选了我们对S1P激动剂和鞘氨醇激酶抑制剂的重点化学文库，并鉴定出一种命中化合物，在最小化的化学操作后，该化合物产生了铅化合物，从而驱动淋巴细胞增多症，并驱动SPNS2抑制剂预期的血浆S1P。通过迭代化学合成和药理测试，我们将优化铅SPNS2抑制剂，并发现并优化其他化学系列SPNS2抑制剂。最终，我们将使用适合体内应用的药代动力学特性生成有效的SPNS2抑制剂。通过对其他S1P相互作用的蛋白质（包括S1P受体，分解代谢和合成代谢酶以及另一种erythroctyte特异性特异性S1P Transporter，MFSD2B）的其他S1P相互作用的蛋白质，将确定SPNS2抑制剂的选择性。在开发SPNS2抑制剂时，我们将使用血浆S1P水平和外周血淋巴细胞计数作为靶标参与的生物标志物。 SPNS2抑制剂将部署在指示免疫调节的一系列疾病模型中。此外，我们将评估SPNS2抑制剂，以了解与S1P信号传导有关的潜在不良事件，包括血管泄漏，心动过缓和耳毒性。在最佳方面，我们的研究将验证SPNS2作为免疫系统调节的治疗靶标。至少，我们将提供可靠的化学工具来探索S1P的复杂生物学。