INDUCTION OF TOLERANCE VIA DEC-205 ON DENDRITIC CELLS

通过 DEC-205 对树突状细胞诱导耐受

• 批准号: 6100073
• 负责人: Ralph Marvin Steinman
• 金额: $ 8.55万
• 依托单位: ROCKEFELLER UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-06-01 至 2000-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6100073
• 关键词: MHC class II antigen; T lymphocyte; antigen presentation; antigen receptors; antireceptor antibody; autoimmunity; dendritic cells; glycoproteins; laboratory mouse; microorganism hemagglutinin; monoclonal antibody; receptor binding; thymectomy; thymus; tissue /cell culture

Dendritic cells are specialized antigen presenting cells [APCs] for initiating T cell-dependent immunity in situ. Dendritic cells also can mediate tolerance, centrally in the thymus and perhaps peripherally as well. This subproject will approach the potential of dendritic cells to silence T cells. We will take advantage of a receptor, DEC-205, that is abundant on Dendritic and certain Epithelial Cells. DEC-205 was isolated and cloned, and has the structure of a DECalectin. DEC-205 mediates adsorptive uptake of rabbit anti-DEC-205 via coated pits and multivesicular endosomes, and efficient presentation to Ig-specific, T cells. When a rat mAb to DEC-205 is injected into mice, the mAb targets to dendritic cells but within a week, the T cells become tolerant to an immunogenic challenge of rat Ig in CFA. Here we will target peptides via DEC-205 in vivo to determine the tissue distribution of the injected peptide and its tolerizing activity. We hypothesize that thymic tolerance would ensue following presentation by medullary dendritic cells and possibly cortical epithelium, while peripheral tolerance may develop because of targeting to immature subsets of dendritic cells or by charging these APCs with very high doses of peptide. The dose requirements and duration of tolerance to rat anti-DEC- 205 will be compared with rat mAbs targeted to other cells and dendritic cell constituents. An I-Ea peptide that binds to I-A/b and is recognized by the Y-Ae mAb will be coupled to anti-DEC-205 and used to visualize processing and targeting in vivo, as well as tolerance to I-Ea peptide. Likewise an influenza HA peptide will be coupled to anti-DEC-205 to follow the response of central and peripheral T cells in HA-specific TCR transgenic lines. In parallel, we will screen a large panel of glycoproteins and nonglycosylated proteins for presentation via DEC-205 and carry out structure-function analyses of the DEC-205 domains that are involved in presentation. Preliminary data show presentation of fetuin by DEC-205 transfectants. Glycoprotein tolerance in vivo will be assessed. Finally the effects of the genetic deletion of DEC-205 in marrow and nonmarrow derived APC compartments will be documented. Within the context of this program, we will therefore identify active ligands for DEC-205 and test if targeting MHC II products via this receptor provides a new molecular approach for autoimmune intervention. By targeting autoantigens to critical subsets of APCs, this approach aims to silence disease-producing T cells in type I diabetes and other autoimmune diseases.

树突状细胞是专门的抗原呈递细胞 [APC] 原位启动 T 细胞依赖性免疫。 树突状细胞还可以 介导耐受性，集中在胸腺，也可能在外周 出色地。 该子项目将探索树突状细胞的潜力 沉默 T 细胞。 我们将利用受体 DEC-205，即 大量存在于树突状细胞和某些上皮细胞中。 DEC-205 被分离 并被克隆，并且具有 DECalectin 的结构。 DEC-205 介导 通过包被的凹坑吸附吸收兔抗DEC-205 多囊泡内体，并有效呈递 Ig 特异性、T 细胞。 当将针对 DEC-205 的大鼠单克隆抗体注射到小鼠体内时，单克隆抗体的目标是 树突状细胞，但在一周内，T 细胞变得耐受 CFA 中大鼠 Ig 的免疫原性攻击。 在这里，我们将通过 DEC-205 体内靶向肽来确定组织 注射肽的分布及其耐受活性。 我们 假设胸腺耐受性会在出现后出现 髓质树突状细胞和可能的皮质上皮，而 由于针对不成熟的亚群，可能会产生外周耐受性 树突状细胞或通过给这些 APC 充电非常高剂量的 肽。 大鼠抗DEC-的剂量要求和耐受持续时间 205 将与针对其他细胞和树突状细胞的大鼠单克隆抗体进行比较 细胞成分。 与 I-A/b 结合并被识别的 I-Ea 肽 Y-Ae mAb 将与抗 DEC-205 偶联并用于可视化 体内加工和靶向，以及对 I-Ea 肽的耐受性。 同样，流感 HA 肽将与抗 DEC-205 偶联，然后 中枢和外周 T 细胞对 HA 特异性 TCR 的反应 转基因系。 与此同时，我们将筛选一大组糖蛋白和 非糖基化蛋白质通过 DEC-205 呈现并进行 DEC-205结构域的结构-功能分析涉及 推介会。 初步数据显示 DEC-205 呈现胎球蛋白 转染子。 将评估体内糖蛋白耐受性。 最后 DEC-205 基因缺失对骨髓和非骨髓的影响 派生的 APC 隔间将被记录。 因此，在该计划的背景下，我们将确定积极的 DEC-205 的配体并测试是否通过此靶向 MHC II 产品 受体为自身免疫干预提供了一种新的分子方法。 通过将自身抗原靶向 APC 的关键子集，该方法旨在 沉默 I 型糖尿病和其他疾病中产生疾病的 T 细胞 自身免疫性疾病。