Immune tolerance in humanized translational models to cure diabetes

描述（由申请人提供）：本申请的重点是研究人类T细胞在诱导1型糖尿病（T1D）和免疫耐受分解过程中的作用。我们寻求开发和利用一种新的人源化小鼠模型系统来直接评估临床相关的治疗方法，以诱导T细胞耐受和治愈糖尿病。我们已经开发了一种与人类相关的小鼠模型，我们可以在体内想象，实时地解决糖尿病期间免疫细胞和目标胰腺细胞之间相互作用的基本机制。该模型系统将有助于促进治疗方法的测试，以选择性地靶向糖尿病源性人类T细胞治疗T1D，作为临床前模型和实验室与床边之间的桥梁。该应用程序的总体目标是利用人源化小鼠模型来识别导致糖尿病的主要免疫靶点，并选择性地沉默这些破坏性T细胞。我们的中心假设是胰岛抗原，包括胰岛素、胰岛素前原、GAD、IA2和IGRP是免疫系统的主要靶点，并导致β细胞死亡和糖尿病。我们的假设是建立在强有力的研究基础上的，这些研究表明，化学固定在耐受性细胞上的胰岛素蛋白能够逆转新发糖尿病NOD小鼠的糖尿病。尽管这些蛋白在小鼠模型中作为糖尿病发病机制的靶点，但我们并不完全了解人类T1D患者的特异性T细胞反应。我们已经启动了一项强有力的合作来研究这些免疫靶点，使用人源化小鼠模型来询问糖尿病发展过程中的人类免疫细胞。利用转基因小鼠在NOD.scid上表达与糖尿病相关的HLA- a2.1和HLA- dq8等位基因。IL-2-Rgamma c-/-小鼠MHC I-/- MHC II-/-背景我们将测试耐受性治疗，以选择性地靶向这些糖尿病相关蛋白作为转译性T1D治疗。本应用的目标是：1)建立和验证人类HLA人源化小鼠模型，该模型能够从HLA匹配的糖尿病患者中进行多系免疫重建和糖尿病的发展；2)利用活体双光子成像确定人源化小鼠耐受性破坏和糖尿病诱导过程中人类T细胞与胰岛移植组织的动态运动和细胞相互作用。3)在人源化胰岛移植长期存活模型中，鉴定和确定抗原特异性耐受诱导后对移植胰岛的功能和生物免疫反应。

DESCRIPTION (provided by applicant): This application is focused on studying human T cells during the induction of type 1diabetes (T1D) and the breakdown of immunological tolerance. We seek to develop and utilize a novel humanized mouse model system to directly assess clinically relevant therapies to induce T cell tolerance and cure diabetes. We have developed a human relevant mouse model that we can imagine in vivo, in real time to address the basic mechanisms underlying the interplay between the immune cells and the target pancreatic beta cells during diabetes. This model system will help facilitate the testing of therapeutics to selectively target diabetogenic human T cells for treatment of T1D, as a pre-clinical model and a bridge between bench and bedside. The overall objective of this application is to utilize humanized mouse models to identify the major immune targets responsible for diabetes and selectively silence only these destructive T cells. Our central hypothesis is that islet antigens, including insulin, preproinsulin, GAD, IA2, and IGRP are major targets of the immune system and lead to beta cell death and diabetes. Our hypothesis has been formulated on the basis of strong research demonstrating that insulin protein chemically fixed to tolerogenic cells was able to reverse diabetes in newly diabetic NOD mice. Despite the role of these proteins as targets for diabetes pathogenesis in mouse models, we do not fully understand the specific T cell responses in human patients suffering from T1D. We have initiated a strong collaboration to investigate these immune targets using humanized mouse models to interrogate human immune cells during diabetes development. Using a transgenic mouse expressing the diabetes linked HLA I and HLA II alleles for HLA-A2.1 and HLA-DQ8 on the NOD.scid.IL-2-Rgamma c-/- mouse MHC I-/- MHC II-/- background we will test tolerogenic therapies to selectively target these diabetes relevant proteins as a translational T1D cure. The goals of this application are to 1) Establish and validate a human HLA humanized mouse model capable of multi-lineage immune reconstitution and diabetes development from HLA matched diabetic patients, 2) Determine the dynamic motility and cellular interactions of human T cells with islet graft tissue during the breakdown of tolerance and induction of diabetes in the humanized mouse using intravital two-photon imaging, and 3) Characterize and determine the functional and biological immune response against transplanted islets following antigen specific tolerance induction in the humanized model for long term islet graft survival.