Local regulation and deletion of T cells to induce tolerance and establish long-term survival of high-risk corneal transplants

局部调节和删除 T 细胞以诱导耐受并建立高风险角膜移植物的长期存活

• 批准号: 10372048
• 负责人: Robert Benjamin Levy
• 金额: $ 39.74万
• 依托单位: UNIVERSITY OF MIAMI SCHOOL OF MEDICINE
• 依托单位国家: 美国
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-04-01 至 2024-02-29
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10372048
• 关键词: Allogenic; Allograft Tolerance; Allografting; Antigens; Beds; Binding; Blindness; Blood Vessels; Bromodomain; Cells; Chimeric Proteins; Clinical; Cornea; Corneal Neovascularization; Cyclophosphamide; Data; Dose; Effector Cell; Endothelium; Epigenetic Process; Exhibits; FOXP3 gene; Failure; Family; Genes; Goals; Graft Rejection; Graft Survival; Hematopoietic Stem Cell Transplantation; Histocompatibility Antigens; Human; IL2RA gene; Immune; Immune Tolerance; Immune system; Immunity; Immunologics; Immunosuppression; In Situ; Inflammation; Inflammation Mediators; Inflammatory; Interleukin-2; Investigation; Keratoplasty; Kinetics; Liquid substance; Mediating; Medical; Monitor; Monoclonal Antibodies; Mus; Organ; Organ Transplantation; Pathway interactions; Patients; Population; Positioning Attribute; Production; Protocols documentation; Reagent; Regulation; Regulatory T-Lymphocyte; Reporter; Signal Transduction; Skin Transplantation; Skin graft; Solid; Survival Rate; T-Lymphocyte; Testing; Time; Tissues; Translating; Transplant Recipients; Transplantation; Transplantation Tolerance; Tumor Necrosis Factor Receptor; Tumor-infiltrating immune cells; United States; Vascular Endothelial Growth Factors; Vision; Work; allotransplant; combinatorial; corneal allograft; corneal scar; cytokine; effector T cell; epigenetic regulation; experimental study; high risk; immunodeficient mouse model; in vivo; in vivo Model; inhibitor; macrophage; news; novel; pre-clinical; prevent; skin allograft; success; time use; translational applications; translational approach; vision rehabilitation

Immunological rejection is the most common cause of corneal allo-transplant failure particularly when the recipient has a high risk vascularized (HRV) corneal bed. In fact, of the 40,000 patients per year receiving a CT for vision rehabilitation, 4-6,000 are considered HRV and the success rate is dismal (<30%). Induction of immune tolerance for these transplants is a critical and unmet medical need according to the NEI. (https://nei.nih.gov/news/scienceadvances/advances/corneal_transplantation). The studies proposed in this application will develop a unique combinatorial strategy never tested in a solid organ transplant to induce long- term tolerance in recipients of high-risk vascularized corneal transplants (HRVCT) through sequential: a) cyclophosphamide (Cy) deletion of antigen (Ag) specific effector T cells (Aim 1), b) immune suppression via marked in vivo Treg expansion (Aim 2) and c) inflammatory gene epigenetic regulation via bromodomain inhibitors BETi (Aim 3). Our preliminary data demonstrate that the use of brief, low dose cyclophosphamide (Cy) administered post-CT can dramatically prolong allograft survival by deleting effector T cells and diminishing corneal neovascularization. Our novel two-pathway strategy additionally targeting the TNF receptor super family 25 (TNFRSF25) using a fusion protein (TL1A-Ig) induces marked expansion of CD4+FoxP3+ Tregs systemically and within the ocular compartment. Importantly, these Tregs exhibit highly potent effector / suppressive activity. Preliminary data demonstrates that epigenetic regulation using a bromodomain inhibitor (BETi) can diminish pro-inflammatory cytokine production in vivo while simultaneously not interfering with Treg expansion and function. Excitingly in the context of this proposal, BETi significantly diminished clinical changes to the cornea when locally administered. We posit high-risk cornea is the ideal tissue to test this hypothesis because there is opportunity to locally modulate immunity and inflammation and we will apply elegant in vivo models to study, monitor and isolate antigen specific effector T cells and antigen specific Tregs using our newly developed B6-Nur77GFPFoxP3RFP mice. The studies proposed in this application will provide a unique opportunity to develop and test a 3-step combinatorial mechanism (CT-Cy, Treg, and BETi) for the establishment of allograft tolerance to maintain permanent HRVCT. Significantly, because HRVCT behave similarly to other vascularized organ transplants, work here can be applied to other tissues to induce transplant acceptance. Therefore, we will begin to test our approach through Treg manipulation in skin transplants first, using orthotopic mouse grafts and then continue by testing our strategy for translational application in humans by using human skin allografts in an immunodeficient mouse model and utilizing novel human reagents (mAb PTX-35) to manipulate human Treg cells. In total, this unique and powerful approach will bring together distinct immune regulatory mechanisms to induce tolerance to transplant antigens for the treatment of corneal blindness and other conditions requiring solid organ transplantation.

免疫排斥是同种异体角膜移植失败的最常见原因，特别是当 受者具有高风险血管化 (HRV) 角膜床。事实上，每年有 40,000 名患者接受治疗 CT用于视力康复，4-6000视为HRV，成功率惨淡（<30%）。感应 根据 NEI 的说法，这些移植物的免疫耐受是一项至关重要且尚未得到满足的医疗需求。 （https://nei.nih.gov/news/scienceadvances/advances/corneal_transplantation）。本文提出的研究 应用程序将开发一种从未在实体器官移植中测试过的独特组合策略，以诱导长期 通过顺序进行高风险血管化角膜移植 (HRVCT) 受者的足月耐受性：a) 环磷酰胺 (Cy) 删除抗原 (Ag) 特异性效应 T 细胞（目标 1），b) 通过以下方式进行免疫抑制 显着的体内 Treg 扩增（目标 2）和 c) 通过溴结构域进行炎症基因表观遗传调控 抑制剂BETi（目标3）。我们的初步数据表明，使用短暂的低剂量环磷酰胺 (Cy) CT 后施用可通过删除效应 T 细胞和 减少角膜新生血管。我们新颖的双途径策略还针对 TNF 受体 超家族 25 (TNFRSF25) 使用融合蛋白 (TL1A-Ig) 诱导 CD4+FoxP3+ 显着扩增 系统性和眼室内的 Tregs。重要的是，这些 Tregs 表现出高效的效应/ 抑制活动。初步数据表明，使用溴结构域抑制剂进行表观遗传调控 (BETi) 可以减少体内促炎细胞因子的产生，同时不干扰 Treg 扩展和功能。令人兴奋的是，在该提案的背景下，BETi 显着减少了临床变化 局部给药时到达角膜。我们认为高风险角膜是检验这一假设的理想组织 因为有机会局部调节免疫和炎症，我们将在体内优雅地应用 使用我们的模型来研究、监测和分离抗原特异性效应 T 细胞和抗原特异性 Tregs 新开发的 B6-Nur77GFPFoxP3RFP 小鼠。本申请中提出的研究将提供独特的 有机会开发和测试 3 步组合机制（CT-Cy、Treg 和 BETi） 建立同种异体移植物耐受性以维持永久性 HRVCT。值得注意的是，因为 HRVCT 表现 与其他血管器官移植类似，这里的工作可以应用于其他组织以诱导移植 验收。因此，我们将首先开始通过皮肤移植中的 Treg 操作来测试我们的方法， 使用原位小鼠移植物，然后继续测试我们在人类中的转化应用策略 通过在免疫缺陷小鼠模型中使用人类皮肤同种异体移植物并利用新型人类试剂（mAb PTX-35）来操纵人类 Treg 细胞。总的来说，这种独特而强大的方法将汇集不同的 免疫调节机制诱导对移植抗原的耐受性以治疗角膜 失明和其他需要实体器官移植的疾病。