Engineering pancreatic islets with TGβ protein to overcome rejection

用 TGβ 蛋白改造胰岛以克服排斥反应

• 批准号: 8966928
• 负责人: Haval Shirwan
• 金额: $ 22.5万
• 依托单位: UNIVERSITY OF LOUISVILLE
• 依托单位国家: 美国
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-05-12 至 2017-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8966928
• 关键词: Affect; Affinity; Alloantigen; Allogenic; Antigens; Applications Grants; Area; Autoantigens; Autoimmune Diseases; Autoimmune Process; Autoimmunity; Beta Cell; Biological; Biotin; C57BL/6 Mouse; Cells; Characteristics; Chimeric Proteins; Chronic; Clinical; Data; Development; Diabetes Mellitus; Diabetic mouse; Disease; Economic Burden; Ectopic Expression; Engineering; Failure; Family suidae; Fibrosis; Generations; Goals; Graft Rejection; Graft Survival; Health; Homeostasis; Human; IL2RA gene; Immune; Immune response; Immune system; Immunosuppression; Immunosuppressive Agents; Inbred BALB C Mice; Inbred NOD Mice; Insulin; Insulin-Dependent Diabetes Mellitus; Intervention; Islet Cell; Islets of Langerhans; Islets of Langerhans Transplantation; Kidney; Ligands; Maintenance; Mediating; Membrane; Memory; Methods; Modeling; Molecular; Molecular Chaperones; Morbidity - disease rate; Mus; Natural regeneration; Pancreas; Pancreas Transplantation; Pharmaceutical Preparations; Play; Population; Proteins; Protocols documentation; Recovery; Regulation; Regulatory T-Lymphocyte; Reporting; Rodent Model; Role; Safety; Series; Signal Transduction; Sirolimus; Source; Splenocyte; Streptavidin; Suggestion; Surface; System; T-Lymphocyte; Therapeutic; To autoantigen; Toxic effect; Transforming Growth Factor beta; Transgenic Organisms; Transplantation; Viral Vector; base; clinically relevant; crosslink; design; diabetic; effective therapy; efficacy testing; gene therapy; human disease; immune function; immunoregulation; improved functioning; islet; lymph nodes; macrophage; mortality; mouse model; novel; novel strategies; pleiotropism; prevent; receptor; standard care

DESCRIPTION (provided by applicant): Type 1 diabetes (T1D) continues to be a major source of morbidity and mortality in over 0.9% US population with an economic burden in billions of dollars. The two current methods used to treat T1D are insulin therapy and allogeneic islet/pancreas transplantation (Tx), both of which have major limitations. Insulin administration does not completely prevent the complications associated with diabetes. Allogeneic islet/pancreas Tx suffers from rejection as well as renal and islet toxicities associated with chronic use of immunosuppressive drugs. Therefore, the primary objective of this grant proposal is to establish a novel immunomodulatory protocol to confer tolerance to allogeneic islet grafts in the absence of continuous immunosuppression. This will be achieved by engineering allogeneic islets ex vivo to transiently display on their surface a novel form of TGFß1, SA-TGFß, protein and use the engineered islets to induce tolerance and treat T1D using rodent models. T1D and allogeneic islet cell destruction is primarily mediated by T cells directed at unique beta cell and Tx antigens. Controlling the function of T pathogenic cells is, therefore, critical to tolerance induction to auto/alloantigens and treatment of T1D using allogeneic islets. We herein propose to use SA-TGFß as an immunomodulatory molecule to achieve this goal. TGFß1 has pleiotropic immune functions and is critical for tolerance to self-antigen. TGFß also plays an important role in acquired tolerance to auto and alloantigens using various immunomodulatory approaches. Most importantly, ectopic expression of TGFß in pancreatic islets using transgenic systems or viral vectors proved effective in inducing tolerance to autoantigens in NOD mouse model of human T1D. However, continuous expression of this molecule is associated with massive fibrosis and long-term beta cell failure. Importantly, transient expression of TGFß in beta cells using inducible transgenic systems overcame its deleterious effects without compromising its tolerogenic function. Inasmuch as this transgenic approach is not applicable to clinical islet Tx, we envisioned that the transient display of TGFβ at protein level on the surface of islets in a clinically applicable manner may achieve tolerance without its reported complications arising from continuous expression. In limited preliminary studies, we demonstrated that the transient display of SA-TGFß on pancreatic islets was effective in overcoming rejection in a chemically induced islet Tx model. Building on these strong preliminary data, we herein propose to use SA-TGFß-engineered allogeneic islets as a means of immunomodulation to prevent graft rejection and treat diabetes in chemically and spontaneously diabetic mouse models. A series of studies will be conducted to delineate the implicated mechanisms of the tolerance. Rapid and transient display of SA-TGFß protein on pancreatic islets offers a whole new means of intervention in the areas of autoimmunity and Tx. This approach possesses the simplicity, safety, and efficacy required to make it a clinically relevant alternative that may accomplish the same goals as gene therapy in the treatment of a broad spectrum of immune-based diseases, including T1D.

描述（由申请人提供）：1 型糖尿病 (T1D) 仍然是超过 0.9% 的美国人口发病和死亡的主要原因，造成数十亿美元的经济负担。目前用于治疗 T1D 的两种方法是胰岛素治疗和同种异体胰岛/胰腺移植 (Tx)，这两种方法都有很大的局限性。施用胰岛素并不能完全预防与糖尿病相关的并发症。同种异体胰岛/胰腺 Tx 会遭受排斥以及与长期使用免疫抑制药物相关的肾和胰岛毒性。因此，这项拨款提案的主要目标是建立一种新的免疫调节方案，以赋予对同种异体胰岛移植物的耐受性。 缺乏持续的免疫抑制。这将通过离体工程同种异体胰岛来实现，使其表面短暂地展示一种新型形式的 TGFβ1、SA-TGFβ 蛋白，并使用工程改造的胰岛诱导耐受性并使用啮齿动物模型治疗 T1D。 T1D 和同种异体胰岛细胞破坏主要由针对独特 β 细胞和 Tx 抗原的 T 细胞介导。因此，控制致病性 T 细胞的功能对于诱导自身/同种异体抗原的耐受性以及使用同种异体胰岛治疗 T1D 至关重要。我们在此建议使用 SA-TGFβ 作为免疫调节分子来实现这一目标。 TGFβ1 具有多效性免疫功能，对于自身抗原的耐受性至关重要。 TGFβ 在使用各种免疫调节方法获得对自身和同种异体抗原的耐受性方面也发挥着重要作用。最重要的是，使用转基因系统或病毒载体在胰岛中异位表达 TGFβ 被证明可以有效诱导人类 T1D 的 NOD 小鼠模型对自身抗原的耐受性。然而，该分子的持续表达与大规模纤维化和长期 β 细胞衰竭有关。重要的是，使用诱导转基因系统在β细胞中瞬时表达TGFβ克服了其有害作用，而不损害其耐受性功能。由于这种转基因方法不适用于临床胰岛Tx，我们设想以临床适用的方式在胰岛表面蛋白质水平上短暂展示TGFβ可能会实现耐受性，而不会出现连续表达引起的并发症。在有限的初步研究中，我们证明 SA-TGFβ 在胰岛上的瞬时展示可有效克服化学诱导的胰岛 Tx 模型中的排斥反应。基于这些强有力的初步数据，我们在此建议使用 SA-TGFβ 工程化的同种异体胰岛作为免疫调节手段，以预防移植排斥并在化学和自发性糖尿病小鼠模型中治疗糖尿病。将进行一系列研究来描述耐受性的相关机制。 SA-TGFβ 蛋白在胰岛上的快速、瞬时展示为自身免疫和 Tx 领域提供了一种全新的干预手段。这种方法具有简单性、安全性和有效性，使其成为临床相关的替代方案，可以在治疗包括 T1D 在内的广泛免疫疾病方面实现与基因疗法相同的目标。