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

• 批准号: 9315285
• 负责人: VERONICA SHUBAYEV
• 金额: $ 10万
• 依托单位: UNIVERSITY OF CALIFORNIA, SAN DIEGO
• 依托单位国家: 美国
• 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/9315285
• 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' 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

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“由影响躯体感觉神经系统的病变或疾病直接引起的疼痛”，具有神经免疫紊乱的某些特征。在响应外周神经损伤，T辅助细胞（Th）淋巴细胞的运输和诱导的主要组织相容性复合体（MHC）II（必不可少的Th细胞识别的捕获和抗原呈递）在受损的神经和脊髓节段是“必要的和足够的”NP的发展。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。我们开创性的计划集中在组织的论文，免疫显性抗原，形成于受损的有髓神经，是低阈值机械性痛觉过敏的来源。触摸是由非伤害性的大髓鞘（Ab）传入，它在受伤后开始解释为毁灭性的疼痛（机械异常性疼痛）轻触摸信号。我们的前沿的初步数据已经确定了一个根本的新机制解释这一现象：选择性的髓鞘碱性蛋白（MBP）的基质金属蛋白酶（MMPs）的蛋白水解释放的隐蔽的免疫显性表位，MBP 84 -104和MBP 69 -86，通常从免疫监视庇护。我们清楚地表明，免疫显性MBP肽注射到完整的神经后产生强大的异常性疼痛。一个有趣的发现是，内源性免疫显性MBP 69 -86表位与MHCII共定位在损伤神经的抗原呈递许旺细胞中，紧邻Ranvier动作电位产生节点。使用最先进的生物化学和分子工具（例如Illumina BeadChip基因阵列、MALDI-TOF质谱、Incidity、NextBio、GeneGo和专有MMP底物数据库）和基本（神经病理学、行为学、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（目的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（目的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单位的脊髓释放依赖于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细胞信号传导网络中的新型催化和非催化MMP靶标，促进适应不良的中枢可塑性和异常的神经免疫突触发生（Aim 3）。这个多学科的计划融合了领先的专业知识和最大的资源，在生物化学的金属蛋白水解（亚历克斯斯特朗金，博士，Sanford-Burnham医学研究所），MMPs在外周髓鞘形成和神经炎症中的神经生物学（Veronica Shubayev，M.D.，UCSD）和疼痛通路（Tony Yaksh，Ph.D.，UCSD）与创新的研究设计，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过渡到NP状态。