Studies of Antigen Stimulation

抗原刺激的研究

基本信息

批准号：
7846477
负责人：
EMIL Raphael UNANUE
金额：
$ 3.74万
依托单位：
WASHINGTON UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2009
资助国家：
美国
起止时间：
2009-06-19 至 2010-09-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/7846477
关键词：
Affinity Amino Acids Antigen Presentation Antigen Presentation Pathway Antigen-Presenting Cells Antigens Area Arts Autoimmune Diabetes Autologous Beta Cell Binding Biochemical Biochemistry Biology CD4 Positive T Lymphocytes Cell Line Cell surface Cellular biology Chemicals Chemistry Collaborations Complex Egg White Enzyme-Linked Immunosorbent Assay Epitopes Family Foundations Frequencies Genes Grant High Pressure Liquid Chromatography Histocompatibility Antigens Class II Housing Human Resources Immunology Infection Inflammation Investigation Ions Isomerism Laboratories Length Listeria monocytogenes MHC binding peptide Mass Spectrum Analysis Mediating Modeling Molecular Monoclonal Antibodies Muramidase Mus Nature Nitrates Paper Pathology Pathway interactions Peptide/MHC Complex Peptides Phagocytes Phase Positioning Attribute Post-Translational Protein Processing Procedures Process Progress Reports Proteins Publications Reagent Reporting Research Research Infrastructure Resources Role Specificity Structure System T-Cell Receptor T-Lymphocyte Time Tissues Transgenes Transgenic Mice Tryptophan Tyrosine United States National Institutes of Health Vesicle base cytokine density experience flexibility globular protein instrument instrumentation interest member professor receptor research study response synthetic peptide

项目摘要

DESCRIPTION (provided by applicant): The purpose of our research is to explain antigen presentation by class II MHC molecules having a strong biochemical, quantitative and mechanistic foundation in order to avoid the many empiricisms that dominate this complex area. We investigated how the model protein antigen hen egg-white lysozyme (HEL) was processed by antigen presenting cells (APC); and established the chemical basis for the processing, selection by, and binding of, its various peptides to I-Ak molecules. This now places us in a situation where these parameters can be strictly related to the biology of the T cell response, i.e. to the specificities and frequencies of HEL clones. The first aim of this renewal is to examine post translational modification of the HEL peptides induced when APC are activated by cytokines. Evidence is presented that activated APC can modify HEL to generate specific T cells to the modified peptides. The initial focus of examination is on HEL peptides in which their tyrosines and tryptophans are nitrated (or oxidized). The plans are to characterize the specificities of the T cells, the biology of the APC that induces the changes, and the biochemical nature of the changes using mass spectrometry approaches. The biology of the T cells to modified peptides will be examined in mice bearing a T cell receptor as a transgene; we intend to identify the possible role of the T cells in inflammation and tissue pathology focusing on beta cells expressing HEL. In the second aim, an explanation is sought for why the response to the various HEL epitopes does not relate to the number of peptide-MHC complex presented by APC. We can quantitate the density of the various peptide-MHC complexes from HEL: those represented at a high level induce about the same number of T cells as those presented at about one- or two-hundred fold less. We consider a possible number of explanations such as molecular competition, competition or cooperativity of the complexes on APC surface, the time of persistence of the complexes, and finally the modulating presence of the murine lysozyme, a strong cross-reactive protein expressed normally on APC. By knowing these important variables, we should be able to have a much fuller understanding of the CD4 T cell responses. The experiments are based on; i) using HEL molecules with relevant biochemical changes that alter either epitope expressions or the persistence of an epitope in APC, ii) tracing the cellular response with TCR receptor transgenic mice to more than one epitope, iii) using APC in transfer systems; and, iv) genetically ablating the murine lysozyme gene.

描述（由申请人提供）：我们的研究目的是通过具有强大生化，定量和机械基础的II类MHC分子来解释抗原表现，以避免许多主导这一复杂区域的经验主义。我们研究了模型蛋白抗原鸡蛋白溶菌酶（HEL）如何通过抗原呈递细胞（APC）处理。并建立了其各种肽与I-AK分子的加工，选择和结合的化学基础。现在，我们将这些参数可能与T细胞反应的生物学严格相关，即与HEL克隆的特异性和频率有关。该更新的第一个目的是检查APC被细胞因子激活时诱导的HEL肽的翻译后修饰。有证据表明，活化的APC可以修改HEL，以生成特定的T细胞对改良的肽。检查的最初焦点是其酪氨酸和色氨酸被硝化（或氧化）的HEL肽。这些计划旨在表征T细胞的特异性，诱导变化的APC的生物学以及使用质谱方法的变化的生化性质。将在带有T细胞受体作为转基因的小鼠中检查T细胞对修饰肽的生物学。我们打算确定T细胞在β细胞表达HEL的炎症和组织病理学中的可能作用。在第二个目标中，寻求解释为什么对各种HEL表位的反应与APC提出的肽-MHC复合物的数量无关。我们可以从HEL中量化各种肽-MHC复合物的密度：高水平表示的诱导T细胞的数量与少于1或两百倍的T细胞的密度相同。我们考虑了许多可能的解释，例如APC表面上复合物的分子竞争，竞争或合作性，复合物的持续时间以及鼠溶菌酶的调节，这是一种强烈的交叉反应蛋白，这是APC上正常表达的强交叉反应蛋白。通过了解这些重要变量，我们应该能够对CD4 T细胞响应有更深入的了解。实验基于； i）使用具有相关生化变化的HEL分子，以改变表位表达或APC中表位的持续性，ii）使用TCR受体转基因小鼠在转移系统中使用APC追踪多个表位，iii）； iv）从遗传上消灭鼠溶菌酶基因。