Generation of Islet Specific T Follicular Regulatory Like Cells for Autologous Cell Therapy of Type 1 Diabetes

项目摘要/摘要 1型糖尿病(T1D)是一种导致胰岛β细胞破坏和终生的自身免疫性疾病 对外源性胰岛素注射的依赖。旨在逆转β细胞的免疫调节剂 自身免疫已被证明可以延迟T1D的诊断，但不能阻止C-肽水平的下降 反映胰岛素的产生。自体细胞疗法(ACT)是一种旨在恢复 通过输注体外扩增的调节性T细胞(Tregs)，免疫设定点回到耐受性。Tregs是 负责下调免疫反应以及它们在糖尿病动物模型中的缺失导致 加速了疾病的发展。然而，ACT的早期临床试验表明，输注的Treg可以持续 但在预防C肽下降方面效果不佳。 该项目建议通过基因从Tregs中产生胰岛特异性T滤泡调节(TFR)细胞 编辑以提高其作为T1D的ACT的实用性。TfR细胞是Tregs的一个特殊子集，它作用于 淋巴结生发中心，成熟的B细胞被T滤泡辅助细胞(TFH)激活。早期B 细胞活化是T1D预后的重要步骤，因为检测T1D患者的类转换胰岛自身抗体 糖尿病前期预示着疾病的发生。因此，创建类似TFR的细胞代表着一种潜在的 通过抑制TFH介导的激活来预防T1D的途径。 以下具体目标概述了利用基因组靶向生产TFR样细胞的目标 作为T1D的潜在细胞疗法。在目标1中，胰岛反应性Tregs将通过非病毒基因组产生 编辑以敲入TCR轨迹中的胰岛反应性TCR。工程树将在体外进行胰岛抗原测试 体内过继转移到NOD小鼠体内以确定其对糖尿病的影响 发病率。在目标2中，TFR细胞特异性趋化因子受体CXCR5将被敲除在rosa26基因座上 并测试了对CXCL13的响应性。基因工程CXCR5阳性胰岛反应树 将被转移到NOD小鼠体内以评估糖尿病发病率和Treg转运到胰腺和 胰腺淋巴结节。 拟议的培训将在佛罗里达大学糖尿病研究所进行，指导人员 托德·布鲁斯科博士和迈克尔·哈勒博士。培训计划将为申请者提供研究设计和 自身免疫、细胞工程和糖尿病模型方面的技术技能以及教学中的专业技能 和科学写作，以促进作为独立调查员的成长。

Project Summary/Abstract Type 1 diabetes (T1D) is an autoimmune disease leading to pancreatic beta cell destruction and lifelong dependence on exogenous insulin injections. Immunomodulatory agents that aim to reverse beta cell autoimmunity have been shown to delay T1D diagnosis but cannot halt the decline of C-peptide levels that reflect insulin production. Autologous cell therapy (ACT) is an investigational therapy that aims to restore the immune set point back to tolerance by infusion of ex vivo expanded regulatory T cells (Tregs). Tregs are responsible for downregulating the immune response and their absence in animal models of diabetes leads to accelerated disease progression. Early clinical trials of ACT, however, show that transfused Tregs persist for years in patients but were ineffective in preventing C-peptide decline. This project proposes to generate islet specific T follicular regulatory (Tfr) cells from Tregs through gene editing to improve their utility as ACT for T1D. Tfr cells are a specialized subset of Tregs that act in the germinal centers of lymph nodes where mature B cells are activated by T follicular helper (Tfh) cells. Early B cell activation is an important step in T1D prognosis as the detection of class-switched islet autoantibodies in the pre-diabetic phase predicts onset of disease. Therefore, creating Tfr-like cells represents a potential avenue of T1D prevention through suppression of Tfh-mediated activation. The following Specific Aims outline the objectives for utilizing genome targeting to produce Tfr-like cells as potential cellular therapies of T1D. In Aim 1, islet reactive Tregs will be produced through non-viral genome editing to knock in islet reactive TCR in the TCR locus. Engineered Tregs will be tested in vitro for islet antigen reactivity and tested in vivo through adoptive transfer into NOD mice to determine its effects on diabetes incidence. In Aim 2, the Tfr cell characteristic chemokine receptor CXCR5 will be knocked in the Rosa26 locus of islet reactive Tregs and tested for responsivity to CXCL13. Engineered CXCR5-positive islet reactive Tregs will be transferred into NOD mice to assess diabetes incidence and Treg trafficking to the pancreas and pancreatic lymph nodes. The proposed training will take place at the University of Florida Diabetes Institute under the guidance of Dr. Todd Brusko and Dr. Michael Haller. The training plan will provide the applicant with research design and technical skills in autoimmunity, cell engineering, and diabetes models as well as professional skills in teaching and scientific writing to facilitate growth as an independent investigator.