Seronegative Autoimmune Encephalopathies: Biomarker Discovery, Validation & Deep Phenotyping

血清阴性自身免疫性脑病：生物标志物的发现、验证

• 批准号: 10416227
• 负责人: Andrew McKeon
• 金额: $ 36.48万
• 依托单位: MAYO CLINIC ROCHESTER
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-02-01 至 2027-01-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10416227
• 关键词: Address; Age; Antibodies; Antigens; Ataxia; Autoimmune; Autoimmune Diseases of the Nervous System; Autoimmune encephalitis; Axon; Bacteriophages; Biological Assay; Biological Markers; Brain Diseases; Cells; Cellular Assay; Cerebellar Ataxia; Characteristics; Clinic; Clinical; Clinical/Radiologic; Complement; Complementary DNA; Data; Degenerative Disorder; Diagnosis; Disease; Early Diagnosis; Early treatment; Encephalitis; Encephalopathies; Ethnic Origin; Future; Goals; Health; Hippocampus (Brain); Human; IL8 gene; Immune; Immune system; Immunofluorescence Immunologic; Immunoglobulin G; Immunologics; Immunoprecipitation; Incidence; Indirect Fluorescent Antibody Technique; Indirect Immunofluorescence; Infectious Encephalitis; Investigation; Laboratories; Length; Libraries; Mass Spectrum Analysis; Methods; Mission; Molecular; Movement Disorders; Mus; Neurologic; Neurons; Nuclear; Ocular Motility Disorders; Outcome; Pathogenicity; Patients; Peptides; Phage ImmunoPrecipitation Sequencing; Phenotype; Process; Protein Microchips; Proteins; Proteome; Public Health; Publishing; Recombinant Proteins; Research; Research Personnel; Serum; Synapses; Techniques; Testing; Therapeutic Trials; Time; Tissues; Translations; Undifferentiated; United States National Institutes of Health; Validation; Western Blotting; Work; amphiphysin; base; biomarker discovery; biomarker identification; chemokine; clinical phenotype; clinical practice; cohort; cytokine; disability; disease mechanisms study; experience; innovation; neuroimmunology; novel; novel marker; novel therapeutics; post-COVID-19; relating to nervous system; screening; sex; specific biomarkers; targeted treatment; therapeutic development; trial design

PROJECT SUMMARY Incidence of autoimmune encephalitis exceeds that of infectious cause, but 50% percent (half of approximate 4000/year in the US) are IgG biomarker negative. Seronegativity hinders diagnosis and pathophysiologic understanding in autoimmune encephalopathies (encephalitis, cerebellar ataxias and other movement disorders). Novel IgG characterization, which attempts to address this gap, is linear and slow occurring at a rate of 1-2 year (using standard tissue-based immunofluorescence assay [IFA] followed by western blots, immunoprecipitation, and mass spectrometry). The long-term goal is to molecularly, clinically and mechanistically characterize autoimmune encephalopathies, and develop targeted autoimmune therapies. The overall objectives in this application, are to: 1) identify disease-specific biomarkers for seronegative autoimmune encephalopathies; 2) molecularly validate novel biomarkers, and 3) clinically, radiologically and immunologically deep-phenotype autoimmune encephalopathies. The central hypothesis is that seronegative autoimmune encephalopathies are characterizable though biomarker discovery. The rationale for this project is that biomarker discovery and translation could occur expeditiously, by leveraging complementary techniques in parallel, that novel biomarkers could be molecularly validated, and that disorders associated with new biomarkers could be neurologically and immunologically deep-phenotyped. To test the central hypothesis the following three specific aims will be pursued: 1) Identify novel biomarkers, initially in 3 partly characterized seronegative autoimmune encephalopathies; 2) determine validity of novel biomarkers; and 3) assess for differentiated clinical phenotypes, and cytokine profile accompaniments. Under the first aim, serum and CSF from seronegative autoimmune encephalopathy patients will be interrogated for neural antibodies using native full-length protein microarrays, as principle technique, complemented by tissue and cell-based IFA for initial IgG screening, and, as needed, phage immunoprecipitation sequencing, and mass spectrometry techniques for verification. For the second aim, newly characterized IgGs will be validated in autoimmune encephalopathy patients and controls by multiple antigen-specific methods (confocal indirect immunofluorescence, and recombinant protein assays [western blot, cDNA-transfected cell-based]). For the third aim, patients with autoimmune encephalopathies with characterized and validated neural IgGs will be deep-phenotyped clinically, radiologically and immunologically, by evaluating for IgG effects in live neuron assays, and cytokine-chemokine profiles. Remaining seronegative cohorts will be immunologically profiled by cytokine-chemokine assays. The research proposed is innovative in the applicant’s opinion, as it focuses on multiplexed biomarker identification, validation, and deep phenotyping. The proposed research is significant because disease-specific biomarkers, with in-depth characterization, allow earlier diagnosis and treatment, and support disease mechanism studies.

项目总结 自身免疫性脑炎的发病率超过感染性原因，但50%(约一半) 在美国，每年4000人)是免疫球蛋白生物标志物阴性。血清阴性阻碍诊断和病理生理 对自身免疫性脑病(脑炎、小脑性共济失调等)的认识 紊乱)。试图解决这一差距的新的免疫球蛋白特征是线性的，发生在 1-2年的比率(使用标准的组织免疫荧光分析[IFA]，然后是免疫印迹， 免疫沉淀和质谱分析)。长期目标是从分子、临床和 从机制上描述自身免疫性脑病，并开发有针对性的自身免疫疗法。这个 本申请的总体目标是：1)识别血清阴性的疾病特异性生物标志物 自身免疫性脑病；2)分子验证新的生物标记物；3)临床、放射学和 免疫学深层表型自身免疫性脑病。中心假设是血清阴性 通过发现生物标记物，自身免疫性脑病是有特征的。这个项目的基本原理是 这种生物标记物的发现和翻译可以通过利用补充技术在 同样，新的生物标记物可以得到分子验证，而与新的 生物标志物可能是神经学和免疫学上的深层表型。为了检验中心假说， 将追求以下三个具体目标：1)识别新的生物标记物，初步确定3个部分特征 血清阴性的自身免疫性脑病；2)确定新生物标记物的有效性；以及3)评估 不同的临床表型和细胞因子谱伴随。在第一个目标下，血清和脑脊液 从血清阴性的自身免疫性脑病患者将被询问神经抗体使用自然 作为主要技术的全长蛋白质微阵列，辅之以组织和细胞为基础的IFA 免疫球蛋白的筛选，并根据需要，噬菌体免疫沉淀测序和质谱学技术 以供核实。对于第二个目标，新鉴定的免疫球蛋白将在自身免疫性脑病中得到验证。 通过多种抗原特异性方法(共聚焦间接免疫荧光和 重组蛋白检测[蛋白质印迹法，以细胞为基础]。对于第三个目标，患有 自身免疫性脑病具有特征性和经验证的神经免疫球蛋白，在临床上将是深表型的， 放射学和免疫学，通过评估活神经元分析中的免疫球蛋白和细胞因子-趋化因子的影响 配置文件。其余血清阴性的队列将通过细胞因子-趋化因子分析进行免疫学分析。这个 申请人认为，提出的研究是创新的，因为它侧重于多路生物标记物识别， 验证和深入的表型。这项拟议的研究意义重大，因为疾病特异性生物标记物， 具有深入的特征，允许更早的诊断和治疗，并支持疾病机制研究。