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DENDRITIC AND T CELLS IN ANTI-BACTERIAL lg RESPONSES

树突状细胞和 T 细胞在抗细菌 lg 反应中的作用

基本信息

批准号：
7219524
负责人：
CLIFFORD M SNAPPER
金额：
$ 33.1万
依托单位：
HENRY M. JACKSON FDN FOR THE ADV MIL/MED
依托单位国家：
美国
项目类别：
财政年份：
2001
资助国家：
美国
起止时间：
2001-04-01 至 2011-03-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/7219524
关键词：
Adoptive Transfer Anti-Bacterial Agents Antibodies Antigens B-Lymphocyte Subsets B-Lymphocytes Bacteria Bacterial Polysaccharides Bacterial Proteins Bacterial Vaccines Binding CD4 Positive T Lymphocytes CD40 Ligand Cell Separation Cell Wall Cells Characteristics Class Condition Data Dendritic Cells Depth Development Electronics Employee Strikes Enzyme-Linked Immunosorbent Assay Exhibits Foundations Funding Generations Goals Humoral Immunities Image Immune Immunity Immunization Immunoglobulin G Immunoglobulin M Immunoglobulins Immunologic Memory Immunologics In Situ In Vitro Kinetics Knock-in Mouse Light Mediating Memory Microscopic Morbidity - disease rate Nature Numbers Physiological Play Pneumococcal Pneumonia Pneumonia Polysaccharides Population Problem Solving Production Proteins Receptor Signaling Receptors, Antigen, B-Cell Recruitment Activity Relative (related person)Research Role Serotyping Signal Transduction Specificity Speed Spleen Splenic Tissue Streptococcus pneumoniae T-Lymphocyte Testing Text Time Transgenic Mice Transgenic Organisms Vaccines Wild Type Mouse anti-IgG base cell type design enzyme linked immunospot assay extracellular functional status improved in vivo insight mortality novel pathogen pneumococcal surface protein A response spatiotemporal

项目摘要

DESCRIPTION (provided by applicant): Streptococcus pneumoniae (Pn) is an extracellular bacterium that is a major cause of global morbidity and mortality. Systemic adaptive immunity to Pn is mediated by antibody, especially IgG specific for the capsular polysaccharide (PS), but also for bacterial proteins. Our long-term goal is to elucidate the cellular mechanisms that underlie the distinct differences that exist between in vivo anti-PS and anti-protein Ig responses to intact Pn, as a prerequisite to the development of improved vaccines. In contrast to the current dogma, based on using purified PS antigens, that IgG anti-PS responses are T cell-independent, we demonstrated that the IgG anti-PS response to intact Pn is heavily dependent on CD4+ T cells but nevertheless, still exhibits striking differences in kinetics, generation of memory, and the functional roles of dendritic and T cells relative to the co-induced anti-protein response. In light of these data, the central hypothesis that underlies our proposed research is that differential B cell receptor signaling and/or involvement of functionally distinct B cell subsets are the key parameters that distinguish physiologic anti-PS and anti-protein Ig responses. We will demonstrate that these parameters differentially impact on 1) the temporal compartmentalization of responding B cells within the spleen, and 2) the cellular interactions of the responding B cells with other immune cell types. As a result we will provide a mechanistic basis that will elucidate the observed differences in anti-PS and anti-protein responses. The specific aims are to: 1. Determine the nature and relationships of B cell and dendritic cell subsets, and CD4+ T cells that differentially mediate in vivo anti-PS and anti-protein Ig isotype responses to systemic immunization with intact Pn. We will utilize high speed electronic cell sorting and adoptive transfer of wild-type and genetically altered immune cells combined with ELISPOT and ELISA analyses of antigen-specific Ig isotype production to accomplish this aim. 2. Determine the mechanism by which B cells, DCs, and CD4+ T cells differentially orchestrate anti-PS and anti-protein responses within a spatiotemporal context. We will utilize B cells from BCR knock-in mice with Ig specificity for Pn-derived PS or protein antigens and T cells from CD4+ TCR transgenic mice with specificity for a Pn-derived protein to accomplish this aim. These cells will be used to conduct in vitro functional studies and confocal microscopic analyses of splenic tissue sections post-immunization. These studies are the first to systematically determine the mechanisms that distinguish anti-PS from anti-protein responses to an intact bacterium and provide novel basic immunologic insights with direct relevance to the development of anti-bacterial vaccines.

描述（由申请人提供）：肺炎链球菌（Pn）是一种细胞外细菌，是全球发病率和死亡率的主要原因。对Pn的全身适应性免疫是由抗体介导的，特别是针对荚膜多糖（PS）的IgG，但也针对细菌蛋白。我们的长期目标是阐明体内抗ps和抗蛋白Ig对完整Pn反应之间存在的明显差异的细胞机制，作为开发改进疫苗的先决条件。与目前基于纯化的PS抗原，IgG抗PS反应与T细胞无关的学说相反，我们证明了IgG抗PS对完整Pn的反应严重依赖于CD4+ T细胞，但尽管如此，相对于共同诱导的抗蛋白反应，树突状细胞和T细胞在动力学、记忆的产生以及功能作用方面仍然表现出显著的差异。根据这些数据，我们提出的研究的核心假设是，不同的B细胞受体信号传导和/或功能不同的B细胞亚群的参与是区分生理性抗ps和抗蛋白Ig反应的关键参数。我们将证明这些参数对1)脾脏内应答B细胞的时间区隔化和2)应答B细胞与其他免疫细胞类型的细胞相互作用有不同的影响。因此，我们将提供一个机制基础，将阐明观察到的抗ps和抗蛋白反应的差异。具体目标是：1。确定B细胞和树突状细胞亚群以及CD4+ T细胞对完整Pn全身免疫的体内抗ps和抗蛋白Ig同种型反应的差异介导的性质和关系。我们将利用高速电子细胞分选和野生型和转基因免疫细胞的过继转移，结合ELISPOT和ELISA分析抗原特异性Ig同种型的产生来实现这一目标。2. 确定B细胞、dc细胞和CD4+ T细胞在时空背景下协调抗ps和抗蛋白反应的差异机制。我们将利用来自BCR敲入小鼠的B细胞和来自CD4+ TCR转基因小鼠的T细胞来实现这一目标，B细胞对pn来源的PS或蛋白质抗原具有Ig特异性，而T细胞对pn来源的蛋白质具有特异性。这些细胞将用于免疫后脾组织切片的体外功能研究和共聚焦显微镜分析。这些研究首次系统地确定了区分针对完整细菌的抗ps和抗蛋白反应的机制，并提供了与抗菌疫苗开发直接相关的新的基本免疫学见解。