Tissue-engineered lymph node stroma to study peripheral tolerance in autoimmune diabetes

组织工程淋巴结基质研究自身免疫性糖尿病的外周耐受性

• 批准号: 10299866
• 负责人: Alice Tomei
• 金额: $ 43.28万
• 依托单位: UNIVERSITY OF MIAMI SCHOOL OF MEDICINE
• 依托单位国家: 美国
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-12-01 至 2022-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10299866
• 关键词: Affect; Antigen-Presenting Cells; Antigens; Autoantigens; Autoimmune Diabetes; Autoimmune Diseases; B-Lymphocytes; Biocompatible Materials; Blood Circulation; Cell Count; Cells; Coculture Techniques; Collagen; Contracts; Defect; Development; Disease; Engineering; Frequencies; Genetic Engineering; Goals; Immune; Immune Tolerance; Implant; In Vitro; Inbred NOD Mice; Inflammation; Insulin; Insulin-Dependent Diabetes Mellitus; Lead; Mus; Organ; Pancreas; Phenotype; Porosity; Property; Regulation; Regulatory T-Lymphocyte; Resistance; Reticular Cell; Role; Signal Transduction; Site; Societies; Stromal Cells; T-Lymphocyte; Testing; Tissue Engineering; Tissues; Transgenic Mice; Work; antigen-specific T cells; autoreactive T cell; base; cellular engineering; design; diabetogenic; immunogenic; immunoregulation; implantation; improved; in vivo; innovation; loss of function; lymph nodes; migration; novel; novel strategies; novel therapeutics; overexpression; peripheral tolerance; prevent; recruit; scaffold

Project Summary: Type-1 diabetes (T1D) is caused by autoreactive T cells that selectively destroy insulin-secreting b cells in the pancreas. Loss of immunological tolerance to b cells causes T1D, but the underlying mechanisms are poorly understood, preventing the development of a cure for T1D. A major component of peripheral tolerance to prevent T1D is the regulation of circulating autoreactive T cells in lymph nodes (LNs) by interactions with tolerogenic Ag- presenting cells (APCs) and regulatory T cells, both of which appear to be defective in T1D. Fibroblastic reticular cells (FRCs) form the LN reticula that guide migration and interactions of T cells and APCs. FRCs are also responsible for remodeling the LN and allowing its expansion during inflammation. Relevant to autoimmune diseases, FRCs are non-professional APCs that can induce antigen-specific tolerance by expressing and presenting antigens to specific T cells without co-stimulatory signals, leading to T cell engagement (stimulation and proliferation) followed by deletion. Most studies have been done using transgenic mice for overexpression of artificial (not disease relevant) antigens in FRCs; thus, the role of FRCs in maintaining peripheral tolerance to disease-relevant self-antigens is poorly understood. We found that in T1D, relative frequency, antigen expression levels and reticular organization of LN FRCs are affected. One goal of this proposal is to use innovative tissue-engineered FRC reticula that recapitulate FRC reticular organization in the LN paracortex and T1D known self-antigen expression to study how FRC reticular properties (aim 1.1) and antigens expression levels (aim 2.1) affect T cell engagement in vitro through co-culture studies. While professional APCs can switch to immunogenic phenotypes and promote T1D, non-professional APCs like FRCs are less likely to do so. We showed that promoting formation of FRC reticula expressing T1D antigens is sufficient to induce tolerance and prevent T1D in non-obese diabetic (NOD) mice. Thus, a second goal of this proposal is to test in NOD mice whether we can delete autoreactive T cells from the systemic circulation to ameliorate T1D by (i) attracting them to implanted engineered reticula and by (ii) promoting tolerogenic T cell engagement by modulating FRC reticular properties (aim 1.2) and/or FRC antigen-expression levels (aim 2.2).

项目摘要： 1型糖尿病（T1D）是由自动反应性T细胞引起的，这些T细胞有选择地破坏分泌B细胞 胰腺。对B细胞的免疫耐受性的丧失会导致T1D，但潜在机制很差 理解，阻止了T1D治疗的开发。外围耐受性的主要组成部分 T1D是通过与耐受性Ag-的相互作用的淋巴结（LN）中循环自身反应性T细胞的调节 呈现细胞（APC）和调节性T细胞，它们在T1D中似乎都有缺陷。 成纤维细胞网状细胞（FRCS）形成了LN网状细胞，该网状引导T细胞和APC的迁移和相互作用。 FRC还负责重塑LN并允许其在炎症过程中扩张。与 自身免疫性疾病，FRC是非专业APC，可以通过 表达并呈现抗原对没有共刺激信号的特定T细胞，导致T细胞 参与（刺激和增殖），然后删除。 大多数研究都是使用转基因小鼠进行过过表达人工（无疾病）进行的。 FRC中的抗原；因此，FRC在维持与疾病相关的自我抗原的外围耐受性中的作用是 理解不佳。我们发现在T1D中，相对频率，抗原表达水平和网状组织 LN FRC受到影响。该提案的目标之一是使用创新的组织工程FRC Reticula 在LN副细胞和T1D已知的自我抗原表达中概括FRC网状组织以研究 FRC网状特性（AIM 1.1）和抗原表达水平（AIM 2.1）在体外影响T细胞的参与度 通过共培养研究。 虽然专业的APC可以切换到免疫原性表型并促进T1D，但非专业APC如 FRC不太可能这样做。我们表明，促进表达T1D抗原的Frc网状的形成是 足以诱导耐受性并预防非肥胖糖尿病（NOD）小鼠的T1D。因此，这是第二个目标 建议是在点头小鼠中测试我们是否可以将自动反应性T细胞从系统循环删除到 通过（i）将它们吸引到植入的网状网状和（ii）促进耐受性T细胞的改善T1D 通过调节FRC网状特性（AIM 1.2）和/或FRC抗原表达水平（AIM 2.2）来参与。