Vaccination with MHC-II restricted ApoB100 peptides to prevent atherosclerosis

接种 MHC-II 限制性 ApoB100 肽预防动脉粥样硬化

• 批准号: 8966694
• 负责人: Klaus F. Ley
• 金额: $ 43.63万
• 依托单位: LA JOLLA INSTITUTE FOR IMMUNOLOGY
• 依托单位国家: 美国
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-11-15 至 2018-10-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8966694
• 关键词: Accounting; Adjuvant; Adverse effects; Affect; Affinity; Alleles; Animal Model; Anti-Inflammatory Agents; Anti-inflammatory; Antibodies; Antigen-Presenting Cells; Antigens; Aorta; Apolipoprotein E; Apolipoproteins; Apolipoproteins B; Arterial Fatty Streak; Arteries; Atherosclerosis; Binding; Biological Assay; Biological Markers; Blood Vessels; Bovine Serum Albumin; C57BL/6 Mouse; CD4 Positive T Lymphocytes; Cardiovascular system; Cell surface; Cells; Centers for Disease Control and Prevention (U.S.); Cessation of life; Cholesterol; Chronic; Core Protein; Data; Dendritic Cells; Deposition; Disease; Dose; Epitopes; Evaluation; Event; Face; Fatty acid glycerol esters; Foundations; Frequencies; Government; HLA-DR Antigens; HLA-DRB1; Health; Health Benefit; Heart; Homing; Host Defense; Human; Hypersensitivity; Image; Immune; Immune system; Immunization; Immunology; In Vitro; Inflammation; Inflammation Mediators; Inflammatory; Institutes; Interleukin-10; Knockout Mice; Knowledge; LDL Cholesterol Lipoproteins; Lesion; Leukocytes; Life; Low-Density Lipoproteins; Maintenance; Major Histocompatibility Complex; Mus; Oils; Peptides; Peripheral arterial disease; Persons; Phenotype; Process; Production; Proliferating; Proteins; Public Health; Publishing; Regimen; Regulatory T-Lymphocyte; Reporter; Reporting; Research; Role; Safety; Staining method; Stains; Stroke; T-Lymphocyte; Testing; Th1 Cells; Thinking; Transgenic Mice; Translating; Vaccinated; Vaccination; Vaccines; Work; adaptive immunity; atheroprotective; base; cell type; chemokine; cytokine; design; experience; hypercholesterolemia; in vivo; macrophage; mouse model; nanomolar; oxidized low density lipoprotein; prevent; protein aminoacid sequence; receptor; research study; screening; vaccination strategy

DESCRIPTION (provided by applicant): Vaccination with MHC-II restricted ApoB100 peptides to prevent atherosclerosis. Atherosclerosis is a chronic inflammatory disease of large and medium-sized arteries triggered by elevated levels of low density lipoprotein (LDL). Recent evidence shows that both innate and adaptive immune responses contribute to the disease. Using an in vitro screening assay, we found 34 peptides from mouse apolipoprotein (Apo)B100 that bind major histocompatibility complex (MHC)-II (I-Ab in Apoe-/- mice) with high affinity and tested 5 of them in vivo. We discovered that vaccination with I-Ab-binding ApoB100 peptides is strongly atheroprotective in the Apoe-/- mouse model of atherosclerosis. The reductions of atherosclerotic lesion size are associated with increased IL-10 expression in the aortas of vaccinated mice. Since we find elevated IL-10 in aortas of vaccinated mice, we hypothesize that immunization with ApoB100 peptides induces IL-10-producing Tregs and/or IL-10-producing macrophages. Specific aim 1 is to test which cell type is responsible for IL-10 production in aortas of vaccinated mice. We have crossed Apoe-/- mice to IL-10 reporter mice to identify the IL-10-producing cells. Cell type-specific IL-10 knockout mice (Il10fl/fl x LysM-Cre or x FoxP3- Cre) will identify the relevance of this proposed mechanism. Based on preliminary data, we hypothesize that Tregs afford protection from atherosclerosis. Specific aim 2 is to test the role o regulatory T cells (Tregs) in atheroprotection by ApoB100 peptides. We propose to define the antigen-specific CD4 T cells by surface phenotype and cytokine secretion, test their homing to atherosclerotic mouse aortas and study their interaction with dendritic cells (DCs) in atherosclerotic plaque by live cell multiphoton imaging. Based on preliminary data identifying 30 human ApoB100 peptides that bind many alleles of human MHC-II, we propose that ApoB100-based atheroprotective vaccination strategies are translatable to humans. Specific aim 3 is to translate atheroprotective vaccination to humans. We discovered one peptide that is human-to-mouse ApoB100 sequence-identical and binds to many human MHC-II alleles including DRB1*0101. We will test the effect of this sequence-identical ApoB100 peptide on atherosclerosis in existing mice transgenic for DRB1*0101, optimize vaccination regimens (adjuvant, frequency, dose) and evaluate the potential of tetramers and peptide- specific antibodies as biomarkers reporting successful vaccination. When the proposed work is completed, we will know (1) the role of IL-10 in vaccination-induced atheroprotection (2) the role of Tregs in atheroprotection and the mechanism of their homing and maintenance in the aorta and (3) whether this approach is indeed practical and translatable to humans. We already have an in vitro screening assay and propose to develop biomarkers to test for successful vaccination. Ultimately, a safe and effective atherosclerosis vaccine could have a very large national and world-wide public health impact.

描述（由申请人提供）：用 MHC-II 限制性 ApoB100 肽进行疫苗接种以预防动脉粥样硬化。动脉粥样硬化是一种由低密度脂蛋白（LDL）水平升高引发的大中动脉慢性炎症性疾病。最近的证据表明先天性和适应性免疫反应都会导致这种疾病。通过体外筛选试验，我们发现了来自小鼠载脂蛋白 (Apo)B100 的 34 种肽，它们与主要组织相容性复合体 (MHC)-II（Apoe-/- 小鼠中的 I-Ab）具有高亲和力，并在体内测试了其中 5 种。我们发现，在 Apoe-/- 小鼠动脉粥样硬化模型中，接种 I-Ab 结合 ApoB100 肽疫苗具有很强的动脉粥样硬化保护作用。动脉粥样硬化病变大小的减小与接种疫苗的小鼠主动脉中 IL-10 表达的增加有关。由于我们发现接种疫苗的小鼠主动脉中 IL-10 升高，因此我们推测 ApoB100 肽免疫会诱导产生 IL-10 的 Tregs 和/或产生 IL-10 的巨噬细胞。具体目标 1 是测试哪种细胞类型负责在接种疫苗的小鼠主动脉中产生 IL-10。我们将 Apoe-/- 小鼠与 IL-10 报告小鼠杂交，以鉴定产生 IL-10 的细胞。细胞类型特异性 IL-10 敲除小鼠（Il10fl/fl x LysM-Cre 或 x FoxP3-Cre）将确定该机制的相关性。根据初步数据，我们假设 Tregs 能提供预防动脉粥样硬化的保护作用。具体目标 2 是测试调节性 T 细胞 (Treg) 在 ApoB100 肽的动脉粥样硬化保护中的作用。我们建议通过表面表型和细胞因子分泌来定义抗原特异性 CD4 T 细胞，测试它们向动脉粥样硬化小鼠主动脉的归巢，并通过活细胞多光子成像研究它们与动脉粥样硬化斑块中的树突状细胞 (DC) 的相互作用。基于鉴定出 30 种与人类 MHC-II 的许多等位基因结合的人类 ApoB100 肽的初步数据，我们提出基于 ApoB100 的动脉粥样硬化疫苗接种策略可适用于人类。具体目标 3 是将动脉粥样硬化疫苗接种应用于人类。我们发现了一种与人鼠 ApoB100 序列相同的肽，可与包括 DRB1*0101 在内的许多人类 MHC-II 等位基因结合。我们将在现有 DRB1*0101 转基因小鼠中测试这种序列相同的 ApoB100 肽对动脉粥样硬化的影响，优化疫苗接种方案（佐剂、频率、剂量），并评估四聚体和肽特异性抗体作为报告疫苗接种成功的生物标志物的潜力。当拟议的工作完成后，我们将了解（1）IL-10在疫苗接种诱导的动脉粥样硬化保护中的作用（2）Tregs在动脉粥样硬化保护中的作用及其在主动脉中归巢和维持的机制，以及（3）这是否该方法确实实用并且可以应用于人类。我们已经有了体外筛选试验，并建议开发生物标志物来测试疫苗接种是否成功。最终，安全有效的动脉粥样硬化疫苗可能会对国家和世界范围的公共卫生产生巨大影响。