Immune tolerance in humanized translational models to cure diabetes

描述（由申请人提供）：本申请专注于研究1型糖尿病（T1 D）诱导和免疫耐受破坏过程中的人类T细胞。我们寻求开发和利用一种新的人源化小鼠模型系统，以直接评估临床相关疗法，以诱导T细胞耐受和治愈糖尿病。我们已经开发了一种人类相关的小鼠模型，我们可以在体内想象，在真实的时间，以解决糖尿病期间免疫细胞和靶胰腺β细胞之间相互作用的基本机制。该模型系统将有助于促进选择性靶向致糖尿病人类T细胞治疗T1 D的治疗剂的测试，作为临床前模型和实验室与床边之间的桥梁。本申请的总体目标是利用人源化小鼠模型来鉴定负责糖尿病的主要免疫靶点，并选择性地仅沉默这些破坏性T细胞。我们的中心假设是，胰岛抗原，包括胰岛素，前胰岛素原，GAD，IA 2和IGRP是免疫系统的主要目标，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，化学固定在致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。尽管这些蛋白质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患有T1 D的人类患者的特异性T细胞反应。我们已经发起了一项强有力的合作，使用人源化小鼠模型来研究这些免疫靶点，以在糖尿病发展过程中询问人类免疫细胞。使用在NOD.scid.IL-2-R γ c-/-小鼠MHC I-/- MHC II-/-背景上表达糖尿病相关的HLA-A2.1和HLA-DQ 8的HLA I和HLA II等位基因的转基因小鼠，我们将测试选择性靶向这些糖尿病相关蛋白作为翻译T1 D治愈的致耐受性疗法。本申请的目的是1）建立并验证能够从HLA匹配的糖尿病患者进行多谱系免疫重建和糖尿病发展的人HLA人源化小鼠模型，2）使用活体双光子成像确定人T细胞与胰岛移植物组织在人源化小鼠中耐受性破坏和糖尿病诱导期间的动态运动性和细胞相互作用，和3）表征和测定在用于胰岛移植物长期存活的人源化模型中抗原特异性耐受诱导后针对移植胰岛的功能和生物免疫应答。

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.