Immune regulation by pneumococcus

肺炎球菌的免疫调节

• 批准号: 9317155
• 负责人: Martha Ann Alexander-Miller
• 金额: $ 23.25万
• 依托单位: WAKE FOREST UNIVERSITY HEALTH SCIENCES
• 依托单位国家: 美国
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-07-07 至 2019-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9317155
• 关键词: Address; Adherence; American; Autolysis; Bacteria; Bacterial Infections; Binding; Bronchus-Associated Lymphoid Tissue; Cell physiology; Cells; Centers for Disease Control and Prevention (U.S.); Clinical; Contracts; Cytoplasmic Granules; Data; Disease; Effector Cell; Engineering; Escherichia coli; Fractionation; Funding Mechanisms; Gram-Positive Bacteria; Hospitalization; Host Defense; Human; Immune; Immune Evasion; Immunological Models; Individual; Infection; Laboratories; Lead; Location; Lung; Mechanics; Membrane; Memory; Modeling; Mus; Nature; Peptide Hydrolases; Pneumococcal Infections; Pneumococcal Pneumonia; Polysaccharides; Positioning Attribute; Predisposition; Production; Property; Proteins; Regulation; Sampling; Series; Serotyping; Site; Streptococcus pneumoniae; Streptococcus pneumoniae plY protein; T cell differentiation; T cell regulation; T-Cell Activation; T-Lymphocyte; Testing; Therapeutic; Tissues; Virulence Factors; World Health Organization; alanine aminopeptidase; capsule; combat; cytokine; design; experimental study; extracellular; genetic regulatory protein; immune function; immunoregulation; innovation; insight; novel; pneumococcal surface protein A; response

At the global level, the World Health Organization (WHO) estimates there are ~14 million cases of serious pneumococcal disease and more than 1.6 million people die each year from invasive pneumococcal disease (IPD). Streptococcus pneumoniae has a number of virulence factors that contribute to its ability to cause disease including polysaccharide capsule, pneumolysin and pneumococcal surface proteins A-C. We have recently identified a novel immunoregulatory property of Spn. Our data show exposure of murine effector cells to a soluble fraction generated from mechanically disrupted Spn results in effective inhibition of cytokine production and granule release. The inhibition we observe is a highly novel and unexpected property of pneumococcus. Importantly, this effect is not restricted to a single strain. We have tested an array of clinical and laboratory isolates finding that all could inhibit T effector cell function. In characterizing the inhibitory factor, we found it to be heat labile and protease sensitive. Through a series of fractionation and sequencing approaches, candidate molecules were identified. Two candidates were cloned, engineered to express a His tag, and expressed in E. coli allowing for efficient isolation and further testing. Our data show that one of the candidates could reproduce the T cell inhibitory effect observed with disrupted Spn and in addition, function was found to be independent of the known enzymatic activity of the protein. The ability of Spn to actively regulate function in effector cells presents a new mechanism for immune regulation by this clinically important bacterium. The studies in this application are designed to understand how the differentiation state of the T cell impact susceptibility to the negative regulatory protein. In addition, we propose studies to elucidate the nature of the interaction of the regulatory protein with T cells. Finally, we will determine the susceptibility of human T cells to the negative regulatory capabilities of Spn. These critical questions will be addressed in the following aims. Aim 1 To determine how the differentiation state of a T cell impacts its susceptibility to the immunoregulatory effects of Spn PepN. Aim 2 To determine whether PepN interacts with the extracellular membrane or gains entry into the cell and the potential partners with which PepN interacts. Aim 3 To determine how the presence of Spn components impacts function in human T cells.

在全球范围内，世界卫生组织（WHO）估计有约1400万例 严重的肺炎球菌病，每年有160万人死于侵入性肺炎球菌 疾病（IPD）。肺炎链球菌具有许多毒力因子，有助于其能力 引起疾病，包括多糖胶囊，肺炎和肺炎球菌表面蛋白A-C。我们 最近已经确定了SPN的新型免疫调节特性。我们的数据显示鼠效应子的暴露 细胞到由机械破坏的SPN产生的可溶性分数导致细胞因子有效抑制 生产和颗粒释放。我们观察到的抑制是高度新颖且出乎意料的特性 肺炎球菌。重要的是，这种效果不仅限于单个菌株。我们已经测试了一系列临床 实验室分离株发现所有人都可以抑制T效应细胞功能。 在表征抑制因子时，我们发现它对热不稳定和蛋白酶敏感。通过一个 一系列分馏和测序方法，鉴定出候选分子。有两个候选人 克隆，设计为表达他的标签，并在大肠杆菌中表达，以进行有效的隔离和进一步 测试。我们的数据表明，其中一名候选人可以重现与T细胞抑制作用 SPN中断，此外，发现功能与已知的酶活性无关 蛋白质。 SPN积极调节效应细胞功能的能力提出了一种免疫的新机制 通过这种临床上重要的细菌调节。本应用程序中的研究旨在理解 T细胞的分化状态如何影响负调控蛋白的敏感性。另外，我们 提出的研究以阐明调节蛋白与T细胞相互作用的性质。最后，我们会的 确定人T细胞对SPN负调控能力的敏感性。这些关键 以下目的将解决问题。目标1以确定T细胞的分化状态如何 影响其对SPN PEPN免疫调节作用的敏感性。目标2确定是否PEPN 与细胞外膜或进入细胞和潜在伙伴的相互作用 PEPN相互作用。目标3确定SPN成分的存在如何影响人类T细胞的功能。