Oral Immunity and Adjuvant Receptors

口腔免疫和佐剂受体

基本信息

批准号：
7804085
负责人：
Georgios Hajishengallis
金额：
$ 5.79万
依托单位：
UNIVERSITY OF LOUISVILLE
依托单位国家：
美国
项目类别：
财政年份：
2006
资助国家：
美国
起止时间：
2006-02-01 至 2011-01-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/7804085
关键词：
Address Adjuvant Adjuvanticity Agonist Antibodies Antigen-Presenting Cells Antigens Arts Bacterial Adhesins Binding Biological Assay CD4 Positive T Lymphocytes Catalytic Domain Cell Line Cell Proliferation Cell model Cell physiology Cholera Toxin Co-Immunoprecipitations Complex Data Dendritic Cells Drug Formulations Engineering Enterotoxins Escherichia coli Exhibits Fluorescence Microscopy Fluorescence Resonance Energy Transfer GD1a ganglioside Gangliosides Genitourinary system Human Imaging Techniques Immune response Immunity Immunization Infection Invaded Investigation Ligands Lymphoid Cell Mediating Membrane Microdomains Modeling Molecular Molecular Structure Monitor Mucosal Immune Responses Mucosal Immunity Mucous Membrane Mus Oral Play Point Mutation Production Proteins Reagent Research Personnel Role Route Scanning Signal Transduction Specificity Stimulus Stomach Streptococcus mutans Structure Structure-Activity Relationship Surface System TLR2 gene Techniques Time Toll-Like Receptor 2 Toll-like receptors Toxic effect Toxin Up-Regulation Vaccines base cellular imaging cytokine improved in vivo interdisciplinary collaboration interest microbial monocyte mouse model mutant novel novel vaccines oral immunity oral pathogen pathogen programs receptor receptor expression respiratory response trafficking transcription factor

项目摘要

The need to develop new vaccines against mucosal pathogens has compelled a search for adjuvants that can effectively stimulate mucosal immunity to vaccine proteins, most of which are poor immunogens. Toll- like receptors (TLRs) and gangliosides are considered "adjuvant receptors" because their interaction with certain classes of noxious microbial molecules generates potent immunomodulatory signals in antigen- presenting cells (APCs) that mobilize adaptive immunity. An ideal adjuvant should thus stimulate adjuvant receptors without, however, inducing toxic effects. This proposal will investigate the adjuvant activities of a novel ganglioside-binding TLR2 agonist, recently identified by our group. The molecule under investigation is the pentameric B subunit of a unique E. coli enterotoxin, designated Type Mb(LT-llb) and quite different from Type I enterotoxins such as cholera toxin. In contrast to the intact toxin, the B subunit (designated LT- llb-B) induces TLR2-dependent activation of transcription factor NF-KB, which plays a central role in the induction of immunoregulatory cytokines and costimulatory molecules on APCs, such as dendritic cells. The overall hypothesis is that LT-llb-B exhibits immunomodulatory activity, which requires the cooperation of GD1a ganglioside and TLR2, promotes antigen-presenting cell function, and induces mucosal immunity. We thus aim to elucidate the immunomodulatory mechanisms of LT-llb-B and demonstrate its mucosal adjuvanticity. Specifically, using immunological, biophysical, and cell imaging techniques, we will determine cooperative interactions between gangliosides and TLR2 in response to LT-llb-B, and the importance of these interactions in upregulating dendritic cell-mediated functional costimulation to CD4+T cells. Moreover, it will be determined if these adjuvant mechanisms of LT-llb-B correlate with induction of mucosal adjuvant activity in vivo. The proposed studies are supported by a plethora of preliminary findings and are facilitated by the availability of (a) engineered wild-type and single point substitution mutants of LT-II molecules, (b) model cell systems where expression of receptors of interest is manipulated and (c) a well-established mouse mucosal immunization model. Using these models and state-of-the-art interdisciplinary techniques, the generated data will form the basis for our ultimate objective which is to establish LT-llb-B as a safe and effective adjuvant in vaccine formulations against oral or other mucosal pathogens.

开发针对粘膜病原体的新疫苗的需要迫使人们寻找佐剂能有效刺激粘膜对疫苗蛋白的免疫，而疫苗蛋白大多是不良免疫原。收费- 样受体（TLR）和神经节苷脂被认为是“佐剂受体”，因为它们与某些类别的有害微生物分子在抗原中产生有效的免疫调节信号调动适应性免疫的呈递细胞（APC）。因此，理想的佐剂应该刺激佐剂然而，受体不会引起毒性作用。该提案将调查辅助活动我们小组最近发现了一种新型神经节苷脂结合 TLR2 激动剂。正在研究的分子是一种独特的大肠杆菌肠毒素的五聚体 B 亚基，指定为 Mb 型 (LT-llb)，并且完全不同来自 I 型肠毒素，例如霍乱毒素。与完整的毒素相比，B 亚基（指定为 LT- llb-B) 诱导转录因子 NF-KB 的 TLR2 依赖性激活，该因子在诱导 APC（例如树突状细胞）上的免疫调节细胞因子和共刺激分子。这总体假设是 LT-llb-B 表现出免疫调节活性，这需要以下方面的合作 GD1a 神经节苷脂和 TLR2，促进抗原呈递细胞功能，并诱导粘膜免疫。我们因此旨在阐明LT-IIb-B的免疫调节机制并证明其粘膜佐剂性。具体来说，利用免疫学、生物物理和细胞成像技术，我们将确定神经节苷脂和 TLR2 之间响应 LT-llb-B 的协同相互作用，以及这些相互作用上调树突状细胞介导的对 CD4+T 细胞的功能性共刺激。而且，将确定 LT-IIb-B 的这些佐剂机制是否与粘膜佐剂的诱导相关体内活性。拟议的研究得到了大量初步结果的支持，并得到了促进通过 (a) LT-II 分子的工程化野生型和单点取代突变体的可用性，(b) 模型细胞系统，其中感兴趣的受体的表达受到操纵，并且（c）一个完善的小鼠粘膜免疫模型。使用这些模型和最先进的跨学科技术，生成的数据将构成我们最终目标的基础，即将 LT-llb-B 建立为安全且可靠的针对口腔或其他粘膜病原体的疫苗制剂中的有效佐剂。