Active tolerosomes, a novel therapy for type 1 diabetes

描述(申请人提供)：1型糖尿病及其相关并发症在美国是一个主要的健康问题。这种疾病起源于T细胞耐受性的崩溃，有一个重要的糖尿病前期阶段，在此期间，受影响的个人基本上没有症状。这为治疗干预提供了一扇机会之窗。我们的目标是产生一种基于免疫的治疗方法，在不引起全球免疫系统紊乱的情况下，选择性地针对致病细胞。 T细胞与其靶细胞之间的有效相互作用的典型特征是形成一种包含克隆型和寡型受体-配体对组合的“免疫突触”。我们的中心假设是，抗原特异性治疗将需要能够模拟这些事件的试剂。作为正常的体内平衡机制的一部分，通过其抗原受体刺激的T细胞可以经历激活诱导的凋亡。这优先发生在潜在的糖尿病致Th1人群中，并被认为至少在一些糖尿病患者中存在缺陷，原因是未能诱导促凋亡分子达到足够的水平。我们将创造合成的抗原特异性促凋亡分子，预计将在体内修复这一功能缺陷。这些新试剂应该诱导靶(致病)细胞的凋亡，而不是潜在的保护性细胞，因此可能导致免疫平衡和耐受性的改变。我们将使用已建立的模型系统来检验这一假设。该项目将包括三个阶段。 1.利用分子克隆技术构建单链多肽-MHC-II类复合体和Fas配体嵌合体。 2.使用一组抗原特异性T细胞克隆和从转基因、糖尿病前期或新糖尿病NOD小鼠中分离的原代细胞对试剂进行体外分析。 3.糖尿病细胞过继转移到NOD/SCI小鼠糖尿病模型的体内试剂分析。 最终，我们预计这一新策略将为改善糖尿病前期或新糖尿病受试者的治疗方法奠定基础。

DESCRIPTION (provided by applicant): Type 1 diabetes mellitus and its associated complications are a major health problem in the US. The disease, which originates from a breakdown in T-cell tolerance, has a significant pre-diabetic stage, during which effected individuals are essentially asymptomatic. This provides a window of opportunity for therapeutic intervention. Our aim is to generate an immune-based therapy that will selectively target the pathogenic cells without causing a global disturbance of the immune system. Productive interactions between T-cells and their targets are typically characterized by the formation of an "immune synapse" containing combinations of both clonotypic and oligotypic receptor-ligand pairs. Our central hypothesis is that antigen-specific therapy will require reagents which can mimic these events. As part of normal homeostatic mechanisms, T-cells stimulated through their antigen receptors can undergo activation induced apoptosis. This preferentially occurs to the potentially diabetogenic Th1 population, and is believed to be defective in at least some diabetic individuals due to a failure to induce pro-apoptotic molecules to sufficient levels. We will create synthetic antigen-specific pro-apoptotic molecules predicted to restore this functional deficit in vivo. These novel reagents should induce apoptosis of the targeted (pathogenic) cells, but spare potentially protective ones, and may therefore lead to a change in the immune balance, and tolerance. We will test this hypothesis using established model systems. The project will involve three phases. 1. The creation of single chain peptide-MHC class II complexes and chimeras with Fas ligand by molecular cloning techniques. 2. In vitro analysis of the reagents using a panel of antigen-specific T-cell clones, and primary cells isolated from transgenic, pre-diabetic or newly diabetic NOD mice. 3. Analysis of the reagents in vivo following adoptive transfer of diabetogenic cells into NOD/SCI mouse models of diabetes. Ultimately we envisage that this novel strategy will form the basis for improved therapies for pre-diabetic or newly diabetic human subjects.