Delineating mechanisms underlying the enhanced stability and functionality of CD2- KO Tregs and chimeric antigen receptor (CAR) Tregs and their application in xenotransplantation

描述 CD2-KO Tregs 和嵌合抗原受体 (CAR) Tregs 稳定性和功能增强的机制及其在异种移植中的应用

• 批准号: 10860495
• 负责人: Mohsen Khosravi Maharlooei
• 金额: $ 23.58万
• 依托单位: MAYO CLINIC ARIZONA
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-01-17 至 2024-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10860495
• 关键词: Acetyl Coenzyme A; Acetylation; Address; Adverse effects; Antibodies; Antigens; Autoimmunity; CD2 Antigens; Cells; Cellular immunotherapy; Citrates; Citric Acid Cycle; Cytosol; Data; Deacetylase; Development; Equilibrium; Excision; FOXP3 gene; Family suidae; Genetic Transcription; Genome; Glycolysis; HLA Antigens; Histone Acetylation; Human; Immune; Immune response; Immune system; Immunosuppression; In Vitro; Inflammatory; Islets of Langerhans Transplantation; Link; Mediating; Metabolic; Metabolism; Mitochondria; Modeling; NADH; Organ; Organ Transplantation; Pathway interactions; Post-Translational Protein Processing; Protein Acetylation; Proteins; Regimen; Regulatory T-Lymphocyte; Resistance; Respiration; SIRT1 gene; Signal Pathway; Signal Transduction; Siplizumab; Source; T cell therapy; T-Cell Depletion; T-Lymphocyte; Transplantation; Ubiquitin; Work; Xenograft procedure; cadmium ion; chimeric antigen receptor; clinical application; conditioning; effector T cell; efficacy evaluation; epigenome; histone modification; humanized mouse; immunoregulation; in vivo; islet; mouse model; prevent; transcriptome

PROJECT SUMMARY Regulatory T cell (Treg) therapy has been widely investigated for control of immune responses in different models of autoimmunity and transplantation. Despite promising results in using Tregs and chimeric antigen receptor (CAR) Tregs for tolerance induction, there are still major concerns regarding the plasticity of Tregs and the effect of T cell-depleting conditioning regimens on these cells that need to be addressed before their clinical application. We have discovered that CD2-KO Tregs and CAR Tregs are not only resistant to a conditioning regimen that includes anti-CD2 antibody (siplizumab), but also have increased FOXP3 expression and Treg functionality in vitro and in vivo. CD2 is a costimulatory molecule that is present in all T cells, including Tregs. Potential direct or indirect link between CD2 signaling and FOXP3 is not known. Our preliminary data show that CD2-KO Tregs have increased mTORc1 activity, glycolysis and mitochondrial respiration. We hypothesize that metabolically- active CD2-KO Tregs generate metabolites that through histone modification or post-translational modifications increase FOXP3 levels. In Aim 1, we will address these hypotheses. We will study CD2+ and CD2-KO Tregs at the genome, epigenome, transcriptome and protein levels and evaluate their metabolism and signaling pathways. In Aim 2, we will explore the translational aspects of this discovery in xenotransplantation setting. We have developed and validated a CAR against a universal pig antigen (class-I swine leukocyte antigen (SLA)) and have shown that SLA CAR Tregs harbor higher suppressive capacity in suppressing anti-pig immune responses in vitro as compared to polyclonal Tregs. We hypothesize that CD2-KO SLA CAR Tregs resist conversion to effector T cells and protect transplanted pig organs in an antigen-specific manner. We will evaluate the resistance of CD2-KO SLA CAR Tregs to conversion in inflammatory conditions and also the efficacy of CD2- KO SLA CAR Tregs in preventing the rejection of pig islets in a humanized mouse model of xeno-islet transplantation. Taken together, this work can potentially lead to the development of safer and more efficient Treg-based immunotherapies. Mechanistic studies could uncover molecules and/or signaling pathways involved in determining the fate/function of Tregs, targeting of which could alter the immune balance toward tolerance.

项目摘要 调节性T细胞（TREG）疗法已广泛研究以控制不同模型中的免疫反应 自身免疫和移植。尽管使用Treg和嵌合抗原受体有希望的结果 （CAR）耐受性诱导的Treg，关于Treg的可塑性仍然存在主要关注点和效果 这些细胞上的T细胞缺乏调节方案需要在其临床应用之前解决。 我们发现CD2-KO Tregs和Car Tregs不仅对适应方案有抵抗力 包括抗CD2抗体（siplizumab），但也具有增加的FOXP3表达和Treg功能 体内和体内。 CD2是一个存在于所有T细胞（包括Tregs）中的共刺激分子。潜在的直接 CD2信号和FOXP3之间的间接链接尚不清楚。我们的初步数据显示CD2-KO Tregs MTORC1活性，糖酵解和线粒体呼吸增加。我们假设这是代谢 主动CD2-KO Treg会生成通过组蛋白修饰或翻译后修饰的代谢物 增加FOXP3水平。在AIM 1中，我们将解决这些假设。我们将研究CD2+和CD2-KO Tregs 基因组，表观基因组，转录组和蛋白质水平，并评估其新陈代谢和信号传导 途径。在AIM 2中，我们将在异种移植设置中探索这一发现的翻译方面。我们 已经开发并验证了针对通用猪抗原的汽车（I类猪白细胞抗原（SLA）） 并表明SLA CAR Tregs在抑制抗鸽子免疫方面具有更高的抑制能力 与多克隆Treg相比，体外反应。我们假设CD2-KO SLA CAR Tregs抵抗 转化为效应T细胞并以抗原特异性方式保护移植的猪器官。我们将评估 CD2-KO SLA CAR Tregs在炎症条件下的抗性以及CD2-的疗效 KO SLA CAR TREG在防止人性化小鼠模型中拒绝猪胰岛的tregs 移植。综上所述，这项工作可能会导致更安全，更高效的发展 基于Treg的免疫疗法。机械研究可能会发现涉及的分子和/或信号通路 在确定Treg的命运/功能时，其靶向可能会改变免疫平衡对公差。