Proteolysis of Myelin as a Source of Neuropathic Pain

髓磷脂的蛋白水解是神经性疼痛的根源

基本信息

批准号：
9094552
负责人：
VERONICA SHUBAYEV
金额：
$ 68.78万
依托单位：
UNIVERSITY OF CALIFORNIA, SAN DIEGO
依托单位国家：
美国
项目类别：
财政年份：
2012
资助国家：
美国
起止时间：
2012-07-30 至 2018-06-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/9094552
关键词：
Action Potentials Affect Analgesics Animals Antigen Presentation Antigen-Presenting Cells Antigens Behavior Behavioral Binding Biochemical Biochemistry Bioinformatics Blood-Nerve Barrier CD28 gene CD4 Positive T Lymphocytes Cell Culture Techniques Cell surface Cells Chronic Clone Cells Complex Data Databases Development Diagnostic Disease Doctor of Medicine Doctor of Philosophy Epitopes Event Exhibits Fiber Figs - dietary Gelatinase B Genes Glutamate Receptor Helper-Inducer T-Lymphocyte Homing Hyperalgesia Immune Immune response Immunodominant Antigens Immunodominant Epitopes Immunologic Monitoring Infiltration Inflammation Injection of therapeutic agent Injury Lead Lesion Light Locomotion MALDI-TOF Mass Spectrometry Major Histocompatibility Complex Matrix Metalloproteinases Mechanics Mediating Medical Research Molecular Myelin Myelin Basic Proteins Myelin Sheath N-Methyl-D-Aspartate Receptors Nerve Nervous system structure Neurobiology Neurons Nociception Nude Rats Pain Pathway interactions Peptides Peripheral Peripheral Nerves Peripheral nerve injury Pharmacology Production Proteolysis Proteome RNA Splicing Ranvier&apos s Nodes Reaction Recovery Research Design Resources Role Schwann Cells Sensory Shelter facility Signal Pathway Signal Transduction Sodium Sodium Channel Solid Source Spinal Spinal Cord Stimulus Synapses System T-Cell Receptor T-Lymphocyte T-Lymphocyte Epitopes Tactile Therapeutic Touch sensation Variant Veronica afferent nerve allodynia antigen processing base bead chip cell motility chronic pain collagenase 3 cytokine glial activation inflammatory pain inhibitor/antagonist injured injury and repair innovation macrophage mechanical allodynia molecular domain myelination nerve injury neuroinflammation neurotransmission novel painful neuropathy prevent programs receptor repaired response sciatic nerve somatosensory synaptogenesis tool trafficking voltage

项目摘要

DESCRIPTION (provided by applicant): Neuropathic pain (NP) is 'pain arising as a direct consequence of a lesion or disease affecting the somatosensory nervous system' that has certain features of a neuroimmune disorder. In response to peripheral nerve damage, T helper (Th) lymphocyte trafficking and induction of major histocompatibility complex (MHC) II (essential to the capture and antigen presentation for Th cell recognition) in the injured nerve and the segmental spinal cord are 'necessary and sufficient' for the development of NP. MHCII has been implicated in differential induction of NP but not inflammatory pain, but the antigens and the processes of their formation remain elusive. Our groundbreaking program centers on the organizing thesis that immunodominant antigens, formed in damaged myelinated nerves, are at the source of low-threshold mechanical hyperpathia. Touch is signaled by non-nociceptive large myelinated (Ab) afferents, which after injury begin interpreting light touch as devastating pain (mechanical allodynia). Our cutting-edge preliminary data have determined a fundamentally novel mechanism explaining this phenomenon: selective proteolysis of myelin basic protein (MBP) by matrix metalloproteinases (MMPs) releases the cryptic immunodominant epitopes, MBP84-104 and MBP69-86, normally sheltered from immunosurveillance. We clearly demonstrate that immunodominant MBP peptides produce robust allodynia upon injection into intact nerve. An intriguing finding is that endogenous immunodominant MBP69-86 epitope co-localizes with MHCII in antigen-presenting Schwann cells of the injured nerve, in close proximity to the action potential-generating nodes of Ranvier. Using state-of-the-art biochemical and molecular tools (e.g. Illumina BeadChip gene arrays, MALDI-TOF mass spectrometry, Ingenuity, NextBio, GeneGo and proprietary MMP substrate database) and fundamental (neuropathological, behavioral, systems) approaches, we will characterize the T cell-dependent and -independent actions of MBP residues in nociception (Aim 1). The molecular domains of myelinated fibers responsible for MBP action in T cell homing and locomotion, and also, the receptors for MBP residues in nerve will be determined (Aim 2). Importantly, we determined that voltage gated sodium channel expression and the spinal release of a glutamate receptor subunit depend on MMP activity. The concluding focus of the proposal are the novel catalytic and non- catalytic MMP targets in regulating T cell trafficking and integration into the spinal neuro-glial signaling network, facilitating maladaptive central plasticity and aberrant neuroimmune synaptogenesis (Aim 3). This multi- disciplinary program merges the leading expertise and utmost resources in biochemistry of metalloproteolysis (Alex Strongin, Ph.D., Sanford-Burnham Medical Research Inst.), neurobiology of MMPs in peripheral myelination and neuroinflammation (Veronica Shubayev, M.D., UCSD), and pain pathways (Tony Yaksh, Ph.D., UCSD) with innovative study designs, which we believe are bound to transform our mechanistic understanding diagnostic and therapeutic practices predicting and preventing the transition to the NP state.

描述（由申请人提供）：神经性疼痛（NP）是“由于影响体感神经系统的病变或疾病直接导致的疼痛”，具有神经免疫性疾病的某些特征。为了应对周围神经损伤，受损神经和节段脊髓中辅助性 T (Th) 淋巴细胞的运输和主要组织相容性复合体 (MHC) II 的诱导（对于 Th 细胞识别的捕获和抗原呈递至关重要）是“必要且必要的”。对于NP的发展来说已经足够了。 MHCII 与 NP 的差异诱导有关，但与炎性疼痛无关，但抗原及其形成过程仍然难以捉摸。我们的开创性计划集中在组织论点上，即在受损的有髓神经中形成的免疫显性抗原是低阈值机械性过敏的根源。触摸是由非伤害性大有髓神经 (Ab) 传入信号发出的，受伤后开始将轻微触摸解释为毁灭性疼痛（机械性异常性疼痛）。我们的前沿初步数据已经确定了解释这一现象的全新机制：基质金属蛋白酶 (MMP) 对髓磷脂碱性蛋白 (MBP) 进行选择性蛋白水解，释放出隐藏的免疫显性表位 MBP84-104 和 MBP69-86，这些表位通常不受免疫监视。我们清楚地证明，免疫显性 MBP 肽在注射到完整神经后会产生强烈的异常性疼痛。一个有趣的发现是，内源性免疫显性 MBP69-86 表位与受损神经的抗原呈递雪旺细胞中的 MHCII 共定位，靠近产生动作电位的朗飞结。使用最先进的生化和分子工具（例如 Illumina BeadChip 基因阵列、MALDI-TOF 质谱、Ingenuity、NextBio、GeneGo 和专有的 MMP 底物数据库）和基本（神经病理学、行为、系统）方法，我们将表征MBP 残基在伤害感受中的 T 细胞依赖性和非依赖性作用（目标 1）。将确定负责 T 细胞归巢和运动中 MBP 作用的有髓纤维的分子结构域，以及神经中 MBP 残基的受体（目标 2）。重要的是，我们确定电压门控钠通道表达和谷氨酸受体亚基的脊髓释放取决于 MMP 活性。该提案的结论重点是调节 T 细胞运输和整合到脊髓神经胶质信号网络中的新型催化和非催化 MMP 靶点，促进适应不良的中枢可塑性和异常的神经免疫突触发生（目标 3）。这个多学科项目融合了金属蛋白水解生物化学（Alex Strongin，博士，桑福德-伯纳姆医学研究所）、外周髓鞘形成和神经炎症中 MMP 神经生物学（Veronica Shubayev，医学博士，加州大学圣地亚哥分校）方面的领先专业知识和最大资源。和疼痛通路（Tony Yaksh，博士，加州大学圣地亚哥分校）的创新研究设计，我们相信这必将改变我们的机械理解诊断和治疗实践，预测和防止向 NP 状态的转变。