Novel Antigen-Specific Immunomodulatory Tregitope-based Therapy to Address Autoimmune Pathogenesis in Graves' Disease

基于新型抗原特异性免疫调节 Tregitope 的疗法可解决格雷夫斯病的自身免疫发病机制

基本信息

批准号：
9410057
负责人：
Anne Searls DeGroot
金额：
$ 17.7万
依托单位：
EPIVAX, INC.
依托单位国家：
美国
项目类别：
财政年份：
2017
资助国家：
美国
起止时间：
2017-09-01 至 2019-08-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/9410057
关键词：
Ablation Address Adverse effects Animal Model Antibodies Antibody Response Antigen Targeting Antigens Autoantibodies Autoantigens Autoimmune Diseases Autoimmune Process Autoimmunity B-Lymphocytes Binding Biological Assay Biological Response Modifier Therapy Bystander Suppression CD4 Antigens CD4 Positive T Lymphocytes Cells Chemicals Child Clinical Clinical Treatment Code Disease Down-Regulation Effector Cell Electroporation Epitopes Eragrostis Evaluation Excision Extracellular Domain Eye diseases FDA approved Formulation Future Gland Glycolates Graves&apos Disease HLA-DR3 Antigen Half-Life Homeostasis Human Hyperthyroidism Hypothyroidism Immune Immune Tolerance Immune response Immunity Immunize Immunoglobulin G Life Link Lymphocyte MHC Class II Genes Mediating Methods Microspheres Modeling Monitor Mus Muscle Operative Surgical Procedures Pathogenesis Patients Peptide Hormones Receptors Peptides Peripheral Peripheral Blood Mononuclear Cell Phase Plasmids Pregnant Women Production Property Radioactive Iodine Recombinants Regulatory T-Lymphocyte Replacement Therapy Research Serum Serum Albumin Splenocyte System T cell response T-Lymphocyte Testing Tetanus Toxoid Thyroid Gland Thyroid Hormones Thyroid stimulating immunoglobulins Thyrotropin Receptor Toxic effect base clinical application extracellular immunoregulation improved in vivo mouse model novel product development receptor binding response

项目摘要

ABSTRACT Significance: Graves’ disease (GD), one of the most prevalent autoimmune diseases, is caused by stimulating autoantibodies (TSAb) to the Thyroid-Stimulating Hormone Receptor (TSHR), resulting in hyperthyroidism. Current methods for managing hyperthyroidism in GD target excess thyroid hormone secretion by ablation or removal of the thyroid or by blocking thyroid hormone synthesis. Each of these therapies is associated with adverse effects, most commonly hypothyroidism requiring life-long replacement therapy. Importantly, none of these approaches address the underlying anti-TSHR CD4 T cell response that contributes to the continued production of TSAb auto-antibodies. Autoimmunity is the result of an imbalance in Teffector:Tregulatory (Teff:Treg) immune-cell homeostasis, and a loss of central or peripheral immune tolerance. T regulatory epitopes (Tregitopes) found in IgG stimulate proliferation and activation of natural and induced Tregs, thereby downregulating a Teff response to self-antigens. These Tregitopes when administered with MHC Class II binding self-antigen peptides, will elicit Antigen- Specific Adaptive Tolerance Induction (ASATI). Hypothesis: Tregitopes, in combination with the target antigen —TSHR CD4 T cell effector peptides — will reduce CD4 T cell activation and T-dependent B cell production of TSAb. Due to the short half-life of peptides in vivo, a practical Tregitope BioTherapeutic (Treg-BT) will need to be administered in a suitable delivery system, that improves its PK/PD properties with minimal toxicity. This project will identify TSHR peptides that stimulate a CD4 effector immune response in PBMC from GD patients, and combine the optimal peptide(s) with Tregitopes in an effective delivery vehicle. In Specific Aim 1, TSHR peptides identified to stimulate a CD4 effector cell response in GD patients will be tested for inhibition by Tregitopes in a TSHR bystander suppression assay. Tregitope peptides with and without TSHR peptides will then be formulated into two Treg-BT delivery vehicles: a) chemically ligated to a recombinant FDA-approved human serum albumin (HSA) or b) formulated into poly(lactic-glycolic acid) (PLGA) microspheres. The Treg-BT will then be tested in the TSHR bystander suppression assay with PBMC from GD patients. In Specific Aim 2, the candidate Treg-BT (HSA- Tregitope + TSHR peptide or Tregitope + TSHR peptides in microspheres, with appropriate controls) will be tested in vivo in a mouse model of GD. HLA-DR3 mice will be genetically immunized with an expression plasmid coding for the extracellular domain of TSHR to generate TSAb. After TSAb response is established, the mice will be treated with the optimized Treg-BT and serum TSAb and CD4 T cell responses will be monitored. Overall Impact: These studies will produce candidate Treg-BT which, combined with TSHR peptides, stimulate a Treg-mediated down-regulation of TSAb autoantibodies, with potential fast-track applicability to the treatment of patients with clinical Graves’ disease.

抽象的意义：格雷夫斯病（GD）是最流行的自身免疫性疾病之一，由以下疾病引起：刺激甲状腺刺激激素受体（TSHR）的自身抗体（TSAb），导致目前治疗 GD 患者甲状腺功能亢进的方法主要针对甲状腺激素过多。通过消融或去除甲状腺或通过阻断甲状腺激素合成来分泌。治疗与不良反应有关，最常见的是需要终生治疗的甲状腺功能减退症重要的是，这些方法都没有解决潜在的抗 TSHR CD4 T 问题。有助于持续产生 TSAb 自身抗体的细胞反应是自身免疫。 Teffector:Tregulatory (Teff:Treg) 免疫细胞稳态不平衡以及中枢神经系统丧失的结果 IgG 中发现的 T 调节表位（Tregitope）刺激增殖。以及天然和诱导的 Tregs 的激活，从而下调 Teff 对自身抗原的反应。这些 Tregitopes 当与 MHC II 类结合自身抗原肽一起施用时，将引发抗原- 特异性适应性耐受诱导 (ASATI) 假设：Tregitopes 与目标相结合。抗原 —TSHR CD4 T 细胞效应肽 — 将减少 CD4 T 细胞活化和 T 依赖性 B 细胞 TSAb 的生产由于肽在体内的半衰期较短，因此需要一种实用的 Tregitope BioTherapeutic。 (Treg-BT) 需要在合适的递送系统中进行给药，以改善其 PK/PD 特性该项目将鉴定刺激 CD4 效应子免疫的 TSHR 肽。 GD 患者的 PBMC 反应，并将最佳肽与 Tregitope 结合起来，以有效的方式在具体目标 1 中，TSHR 肽被鉴定可刺激 CD4 效应细胞反应。 GD 患者将在 TSHR 旁观者抑制试验中测试 Tregitope 的抑制情况。然后，含有和不含 TSHR 肽的肽将被配制成两种 Treg-BT 递送载体：a) 化学连接至 FDA 批准的重组人血清白蛋白 (HSA) 或 b) 配制为然后，Treg-BT 将在 TSHR 旁观者中进行测试。在特定目标 2 中，使用来自 GD 患者的 PBMC 进行抑制测定，候选 Treg-BT (HSA-)。 Tregitope + TSHR 肽或微球中的 Tregitope + TSHR 肽（具有适当的对照）将在 GD 小鼠模型中进行体内测试，对 GD 小鼠进行基因免疫。 TSAb 反应后，编码 TSHR 胞外结构域的表达质粒产生 TSAb。建立后，将用优化的 Treg-BT 和血清 TSAb 和 CD4 T 细胞治疗小鼠总体影响将受到监测：这些研究将产生候选 Treg-BT，与 TSHR 肽结合，刺激 Treg 介导的 TSAb 自身抗体下调，潜在的快速通道适用于治疗临床格雷夫斯病患者。