CRISPR-Modified Cardiac Xenograft Transplantation

CRISPR 改良心脏异种移植

基本信息

批准号：
10188418
负责人：
Richard N Pierson
金额：
$ 79.57万
依托单位：
MASSACHUSETTS GENERAL HOSPITAL
依托单位国家：
美国
项目类别：
财政年份：
2020
资助国家：
美国
起止时间：
2020-06-10 至 2025-05-31
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10188418
关键词：
Address Adenosine Adhesions Adhesives Antibodies Binding Biochemical Biological Assay Blood Blood Coagulation Disorders Blood Platelets Cells Clinic Clinical Clustered Regularly Interspaced Short Palindromic Repeats Coagulation Process Complement DNA cassette Data Development Drug usage Endothelium Erythrocytes Exhibits Family suidae Flow Cytometry Functional disorder Gene Expression Genes Genetic Genetic Engineering Genotype Health Heart Heart Injuries Histology Hour Human Immunosuppression In Vitro Inflammation Injury Integrins Intervention Ischemia Kidney Knock-out Learning Leukocytes Life Liver Lung Measures Mediating Modeling Modification Monoclonal Antibodies Organ Transplantation Organ failure Papio Pathway interactions Pharmaceutical Preparations Phenotype Physiology Positioning Attribute Publishing Refractory Regimen Regulator Genes Reperfusion Injury Reporting Residual state Resources Selectins Steroids Structure TNFRSF5 gene Testing Thrombomodulin Transferase Translating Translations Transplantation Treatment Protocols United States National Institutes of Health Work Xenograft procedure base clinical application clinically relevant complement pathway design ex vivo perfusion experience experimental study genetic regulatory protein heart function heart xenograft immunomodulatory therapies immunoregulation improved in vivo innovation insight novel pre-clinical prevent protein expression targeted treatment thrombotic tool trial design

项目摘要

SUMMARY ABSTRACT: CRISPR-Modified Cardiac Xenograft Transplantation The past three years have witnessed two major breakthroughs in heart xenotransplantation. First, the previously intractable barrier of delayed xenograft rejection (DXR) has been overcome in the pig-to-baboon heart xeno model. In this model, DXR is manifest primarily as consumptive coagulopathy (CC) in the recipient and thrombotic microangiopathy (TM) in the graft. Working in the heterotopic model in baboons, our `Mohiuddin/NIH' group used genetically modified GTKO.hCPRP.hTBM hearts and a treatment regimen including “induction” T and B depletion, MMF, and steroids – all clinically used drugs – with an experimental monoclonal antibody directed against CD40. DXR was prevented for as long as CD40 treatment was continued, and in one instance xenograft survival was extended beyond two years. The second major advance came from the Munich group, who reported consistent survival of orthotopic pig heart xenograft recipients beyond 180 days using our immunomodulatory regimen and GTKO.hCPRP.hTBM hearts. Accomplishing consistent survival of orthotopic heart xenografts had previously been prevented by initial xenograft dysfunction (IXD), a phenomenon refractory to concerted efforts by multiple experienced clinical transplant teams. Importantly, the Munich group found that minimizing graft ischemia was necessary and sufficient to consistently prevent IXD. Discovering that ischemia minimization was sufficient to overcome the IXD barrier is a `breakthrough' advance, even as the mechanism of improved graft protection by ischemia minimization is not yet well understood. In this Project, we hypothesize that IXD mechanisms that injure GTKO.hCPRP.hTBM hearts may be addressed by the additional xeno-focused genetic modifications expressed in one or more versions of Pig 2.0, created by our collaborators at eGenesis using innovative CRISPR-driven gene editing tools. Pig 2.0 is designed to address multiple known xeno-specific injury mechanisms through a combination of 12 xeno- targeted genetic modifications. This Project takes advantage of availability of several well-defined versions of Pig 2.0, our deep experience with multiple in vitro, ex vivo, and in vivo heart xeno models, and a robust mechanistic assay capability to determine whether Pig 2.0 is protected from heart IXD, with or without ischemia minimization (Aim 1). Specifically, we will use these unique resources to learn a) whether versions of Pig 2.0 containing a coagulation cascade regulatory gene cassette are protected from IXD; b) whether ischemia minimization is necessary and/or sufficient to prevent IXD in susceptible Pig 2.0 hearts; and c) to define a clinically acceptable immunosuppression regimen for Pig 2.0 hearts in baboons that is consistently safe and effective (Aim 2). Results from this Project will yield insights likely to catalyze progress for other cell and organ xenografts, and inform clinical heart xenotransplantation trial design.

摘要摘要：CRISPR 修饰的心脏异种移植过去三年，心脏异种移植取得了两大突破。猪与狒狒之间的延迟异种移植排斥（DXR）这一棘手障碍已被克服心脏异种模型中，DXR 主要表现为受体的消耗性凝血病 (CC)。和移植物中的血栓性微血管病（TM），我们在狒狒的异位模型中进行研究。 “Mohiuddin/NIH”小组使用转基因 GTKO.hCPRP.hTBM 心脏和治疗方案包括“诱导”T 和 B 消耗、MMF 和类固醇——所有临床使用的药物——通过实验只要使用 CD40 治疗，就可以预防针对 CD40 的单克隆抗体。持续进行，在一个例子中，异种移植物的存活期延长了两年以上。第二个重大进展来自慕尼黑小组，他们报告了原位的持续存活使用我们的免疫调节方案超过 180 天的猪心脏异种移植受者 GTKO.hCPRP.hTBM 心脏先前已实现原位心脏异种移植物的一致存活。最初的异种移植功能障碍（IXD）阻止了这一现象，这是一种多方共同努力难以治愈的现象重要的是，慕尼黑小组发现，经验丰富的临床移植团队可以最大限度地减少移植物缺血。发现缺血最小化足以持续预防 IXD。克服 IXD 障碍是一项“突破性”进展，尽管通过缺血最小化尚不清楚。在这个项目中，我们勇敢地指出损伤 GTKO.hCPRP.hTBM 心脏的 IXD 机制可能是通过在 Pig 2.0 的一个或多个版本中表达的额外的以异种为中心的基因修饰来解决，由我们在 eGenesis 的合作者使用创新的 CRISPR 驱动的基因编辑工具创建的 Pig 2.0。旨在通过 12 种异种物质的组合来解决多种已知的异种物质特异性损伤机制该项目利用了几个明确定义的版本的可用性。 Pig 2.0，我们在多个体外、离体和体内心脏异种模型方面的丰富经验，以及强大的机械分析能力可确定 Pig 2.0 是否免受心脏 IXD 的影响，无论有无缺血具体来说，我们将使用这些独特的资源来了解 a) 是否为 Pig 2.0 版本。 b) 含有凝血级联调节基因盒的细胞是否免受 IXD 的影响；最小化对于预防易感猪 2.0 心脏中的 IXD 是必要和/或充分的；并且 c) 定义临床上可接受的狒狒 Pig 2.0 心脏免疫抑制方案，始终安全且可靠有效（目标 2）。该项目的结果将产生可能促进其他细胞和器官进展的见解。异种移植，并为临床心脏异种移植试验设计提供信息。