Immunoglobulin Activation of Fibroblasts

成纤维细胞的免疫球蛋白激活

• 批准号: 8314032
• 负责人: TERRY J SMITH
• 金额: $ 37.32万
• 依托单位: UNIVERSITY OF MICHIGAN AT ANN ARBOR
• 依托单位国家: 美国
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-07-01 至 2014-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8314032
• 关键词: Adenoviruses; Animal Model; Animals; Antibodies; Antigens; Attenuated; Autoantigens; Autoimmune Diseases; Autologous; B-Lymphocytes; Binding; CD19 gene; CD3 Antigens; CD34 gene; CD8B1 gene; Cell physiology; Cells; Chemotactic Factors; Chimeric Proteins; Clinical; Cloning; Complex; Connective Tissue; Development; Disease; Environmental Risk Factor; Epithelium; Event; Exhibits; Experimental Animal Model; Fatty acid glycerol esters; Female; Fibroblasts; Frequencies; Generations; Genetic; Health; Home environment; Hormones; Human; Hyaluronan; Immune; Immune system; Immunoglobulin G; Immunoglobulins; Implant; Inbred BALB C Mice; Infiltration; Inflammation; Inflammatory; Insulin-Like-Growth Factor I Receptor; Label; Lead; Luciferases; Lymphocyte; Lymphocyte Activation; Mediating; Modeling; Monozygotic Twinning; Monozygotic twins; Mus; Newly Diagnosed; Non-Invasive Cancer Detection; Ocular orbit; Orbital implants; Pathogenesis; Patients; Phenotype; Play; Pre-Clinical Model; Process; Production; Proteins; Receptor Activation; Role; Series; Signal Transduction; Staging; Syndrome; T memory cell; T-Cell Receptor; T-Lymphocyte; Testing; Thyroid Diseases; Thyroid Gland; Thyroid Hormones; Thyrotropin Receptor; Tissues; Vision; Yeasts; base; charge coupled device camera; cytokine; disease mechanisms study; effective therapy; in vivo; insight; mouse model; mutant; new therapeutic target; patient population; pre-clinical; receptor; thyroid associated ophthalmopathies; yeast two hybrid system

DESCRIPTION (provided by applicant): Graves' disease (GD) is a syndrome caused by as yet unidentified genetic and environmental factors where the thyroid becomes overactive because antibodies (TSI) directed against the thyrotropin receptor (TSHR) drive excess hormone production. GD is also associated with the inflammation, accumulation of hyaluronan (HA), and remodeling of orbital connective tissue. This process is known as thyroid-associated ophthalmopathy (TAO) for which no effective treatment currently exists. A major impediment to our understanding of TAO is the absence of a pre-clinical animal model. We have discovered previously that orbital fibroblasts from patients with TAO exhibit a unique inflammatory phenotype and over-express the insulin-like growth factor-1 receptor (IGF-1R). IGF-1R-activating antibodies (GD-IgGs) are found in virtually all patients with GD. When they bind to this receptor, T cell chemoattractants and HA are synthesized by TAO fibroblasts. We hypothesize that these events underlie lymphocyte infiltration and expansion of the orbital tissue. We have now discovered that GD is also associated with an increased frequency of IGF-1R+ T and B cells and this phenotype conveys a proliferative and survival advantage. Monozygotic (MZ) twins discordant for GD are also discordant for the IGF- 1R+ lymphocyte skew, suggesting an environmental cause. We have also now discovered that patients with GD have increased numbers of circulating CD34+ fibroblast precursors called fibrocytes. Moreover we find fibrocytes infiltrating the TAO orbit and expressing high levels of TSHR and IGF-1R. In orbital fibroblasts and thyroid epithelium, TSHR and IGF-1R form a physical complex and IGF-1R mediates aspects of TSHR signaling. We have succeeded in cloning an adenovirus encoding an IGF-1R1-GFP fusion protein. When female BALB/c mice are immunized with it, they manifest orbital inflammation and produce GD-IgG. We have also implanted TAO fat into SCID NOD3-/- mice and shown that TAO fibrocytes home to that tissue. We hypothesize that IGF-1R represents the second critical auto-antigen in GD and is necessary with TSHR to generate authentic disease. We now propose studies to test our central hypothesis. Specific aim 1) To characterize profiles of CD4+ IGF-1R+ T cells, CD19+IGF-1R+ B cells, and fibrocytes from patients with GD, determine whether they change longitudinally or predict development of TAO, determine whether IGF-1R+ B cells selectively produce pathogenic Abs such as TSI and GD-IgG, and examine additional MZ twins discordant for clinical GD. Specific aim 2) To characterize the interaction between IGF-1R and TSHR by cloning IGF-1R2 mutants and performing yeast two-hybrid analysis. Specific aim 3) To continue exploiting two mouse models of GD created by 1) implanting orbital fat into SCID NOD3-/- mice and 2) double-immunizing mice with adenoviruses encoding IGF-1R and TSHR. We believe that important insights into disease pathogenesis and identification of novel therapeutic targets will emerge from these studies. PUBLIC HEALTH RELEVANCE: Thyroid-associated ophthalmopathy (TAO) is the sight-threatening orbital component of Graves' disease, a syndrome where the thyroid gland becomes over-active. There are currently no effective therapies for TAO because we lack an experimental animal model to study disease mechanisms and test therapies. In this proposal, we identify abnormalities in human immune system that underlie development of TAO, and apply these insights to animal models in which treatments can be developed.

描述（由申请人提供）：格雷夫斯病（GD）是一种由尚未确定的遗传和环境因素引起的综合征，其中甲状腺变得过度活跃，因为针对促甲状腺素受体（TSHR）的抗体（TSI）驱动过量的激素产生。 GD 还与炎症、透明质酸 (HA) 积累和眼眶结缔组织重塑有关。这一过程被称为甲状腺相关眼病（TAO），目前尚无有效的治疗方法。我们理解 TAO 的一个主要障碍是缺乏临床前动物模型。我们之前发现，TAO 患者的眼眶成纤维细胞表现出独特的炎症表型，并过度表达胰岛素样生长因子 1 受体 (IGF-1R)。 IGF-1R 激活抗体 (GD-IgG) 几乎存在于所有 GD 患者中。当它们与该受体结合时，TAO 成纤维细胞会合成 T 细胞趋化剂和 HA。我们假设这些事件是淋巴细胞浸润和眼眶组织扩张的基础。我们现在发现 GD 还与 IGF-1R+ T 和 B 细胞频率增加有关，并且这种表型具有增殖和生存优势。 GD 不一致的同卵双胞胎 (MZ) 的 IGF-1R+ 淋巴细胞偏差也不一致，这表明环境原因。我们现在还发现，GD 患者循环中 CD34+ 成纤维细胞前体（称为纤维细胞）的数量增加。此外，我们发现纤维细胞浸润 TAO 眼眶并表达高水平的 TSHR 和 IGF-1R。在眼眶成纤维细胞和甲状腺上皮中，TSHR 和 IGF-1R 形成物理复合物，IGF-1R 介导 TSHR 信号传导的各个方面。我们成功克隆了编码 IGF-1R1-GFP 融合蛋白的腺病毒。当雌性 BALB/c 小鼠用它免疫时，它们会出现眼眶炎症并产生 GD-IgG。我们还将 TAO 脂肪植入 SCID NOD3-/- 小鼠体内，并证明 TAO 纤维细胞是该组织的归宿。我们假设 IGF-1R 代表 GD 中第二个关键的自身抗原，并且是 TSHR 产生真正疾病所必需的。我们现在提出研究来检验我们的中心假设。具体目标 1) 表征 GD 患者的 CD4+ IGF-1R+ T 细胞、CD19+IGF-1R+ B 细胞和纤维细胞的特征，确定它们是否纵向变化或预测 TAO 的发展，确定 IGF-1R+ B 细胞是否选择性产生致病性抗体，如 TSI 和 GD-IgG，并检查其他与临床 GD 不一致的同卵双胞胎。具体目标2)通过克隆IGF-1R2突变体并进行酵母双杂交分析来表征IGF-1R和TSHR之间的相互作用。具体目标 3) 继续开发两种 GD 小鼠模型，方法是 1) 将眼眶脂肪植入 SCID NOD3-/- 小鼠和 2) 用编码 IGF-1R 和 TSHR 的腺病毒对小鼠进行双重免疫。我们相信这些研究将产生对疾病发病机制和新治疗靶点识别的重要见解。公共健康相关性：甲状腺相关性眼病 (TAO) 是格雷夫斯病的一种威胁视力的眼眶疾病，格雷夫斯病是一种甲状腺过度活跃的综合征。目前TAO还没有有效的治疗方法，因为我们缺乏实验动物模型来研究疾病机制和测试治疗方法。在这项提案中，我们确定了 TAO 发展背后的人类免疫系统异常，并将这些见解应用于可以开发治疗方法的动物模型。