Activation of Xenogeneic Endothelium to Resist Injury

激活异种内皮细胞抵抗损伤

基本信息

批准号：
7522827
负责人：
AGUSTIN P DALMASSO
金额：
$ 48.76万
依托单位：
UNIVERSITY OF MINNESOTA
依托单位国家：
美国
项目类别：
财政年份：
1999
资助国家：
美国
起止时间：
1999-08-16 至 2011-06-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/7522827
关键词：
Abbreviations Acute Address Adenoviruses Agonist Animal Model Animals Antibodies Antigens Apoptosis Apoptotic Area Arteries Atherosclerosis Binding Proteins Blood Blood Vessels Candidate Disease Gene Cardiovascular Surgical Procedures Cell Death Cellular biology Clinical Complement Complement Activation Complement Inactivators Complement Membrane Attack Complex Cycloheximide Cyclosporine Cytoprotection Development Endothelial Cells Endothelium Family suidae Galactosidase Gene Expression Genes Goals Graft Rejection Graft Survival Heart Heart Transplantation Heat-Shock Proteins 70 Histology Human Humoral Immunities IL4 gene Immunologics In Vitro Inflammatory Injury Interleukin-1 Interleukin-13 Interleukin-4 Ischemia Knowledge Left Lipids MAP Kinase Gene MAPK14 gene MEKs Malignant Neoplasms Mediating Mediator of activation protein Medicine Microarray Analysis Minnesota Modeling Molecular Molecular Biology Mus National Research Service Awards Natural Killer Cells Necrosis Operative Surgical Procedures Organ Organ Donor Organ Transplantation Oxidoreductase Paper Pathogenesis Pathway interactions Patients Phosphoric Monoester Hydrolases Phosphotransferases Primates Problem Solving Process Production Progress Reports Protein Phosphatase 2A Regulatory Subunit PR53 Proteins Rattus Regulatory Element Role Signal Pathway Signal Transduction Signaling Protein Small Interfering RNA Solutions Sterols Stimulus Techniques Testing Thromboplastin Thrombosis Transgenic Organisms Transplantation Tumor Necrosis Factor-alpha Universities Vascular Diseases Vascular Endothelium Xenograft procedure attenuation base cobra venom factor cytokine end-stage organ failure human TNF protein iliac artery immunogenicity in vivo interest killings kinase inhibitor membrane biogenesis nonhuman primate novel strategies overexpression prevent protective effect public health relevance research study response

项目摘要

DESCRIPTION (provided by applicant): Xenotransplantation (Xtr) is of interest because of the insufficient supply of human organs. The pig is considered a likely donor species for humans, but there are major barriers to successful Xtr. The first two barriers, hyperacute rejection (HAR) and acute vascular rejection (AVR), are mediated primarily by humoral immunity. HAR can be abrogated, but then AVR will occur. Strategies to interfere with AVR include reducing humoral immunity or inducing tolerance in the recipient, and decreasing immunogenicity or inducing protection in the graft. Our long-term goal is to investigate induction of protection in the donor organ against AVR. HYPOTHESIS: The cytokine IL-4 is capable of inducing broad protection against xenogeneic injury of porcine endothelial cells (ECs) and can be used to prepare an organ for Xtr, such that the organ is protected from HAR and AVR. SPECIFIC AIMS. I. Investigate protection induced by IL-4 in porcine ECs against xenogeneic activation. The activation response of ECs deficient in the main antigen responsible for graft rejection will be studied for IL-1 production and other mediators of EC activation, and the requirements and mechanisms for IL-4 protection will be defined. II. Characterize the mechanisms that participate in protection against complement killing. The participation of the signaling protein Akt is required for IL-4-induced protection. Akt is known to activate several substrates that may result in protection; therefore the identification and characterization of these pathways will be carried out. III. Investigate the role of anti-apoptotic proteins in IL-4-induced protection against apoptosis. The role of Bcl-xL and other protective molecules will be studied in protection from apoptosis elicited with TNF-alpha and with human natural killer cells. In these first three specific aims the protective pathways will be studied with kinase inhibitors and the functional role of candidate proteins will be defined with siRNA. IV. Investigate the protective effect of IL-4 overexpression against HAR and AVR in the mouse-to-rat model of Xtr. The AVR process in this animal model is similar to that in pig-to-primate models and will allow us to define the mechanisms of protection. Mouse hearts will be infected with an adenovirus carrying the IL-4 gene, or an irrelevant gene as control, and then transplanted into rats for studies of graft survival, histology, and gene expression and activation. Studies will be performed at different periods after grafting to establish the efficacy of IL-4 in preventing the manifestations of activation and the pathological course of rejection. It is expected that there will be an attenuation of the intensity and a delay in the manifestation of such processes, and prolongation of graft survival. Accomplishing these goals will result in understanding the mechanisms of protection of IL-4 in donor organs from a different species and to what extent they contribute to successful Xtr, which is essential for those patients with end-stage organ failure for whom no human organs are available. PUBLIC HEALTH RELEVANCE The supply of human organs for transplantation is insufficient, and a potential solution to overcome this shortage is xenotransplantation (using organs from donor animals such as the pig). Accomplishing the goals of this proposal will define a novel approach to modify donor organs for clinical xenotransplantation. This will also provide knowledge for new treatments for vascular diseases, including ischemia and atherosclerosis.

描述（由申请人提供）：由于人体器官供应不足，异种移植（Xtr）引起人们的兴趣。猪被认为是人类可能的供体物种，但成功的 Xtr 存在重大障碍。前两种障碍，超急性排斥反应（HAR）和急性血管排斥反应（AVR），主要由体液免疫介导。 HAR 可以被废除，但随后 AVR 就会发生。干扰 AVR 的策略包括降低受体的体液免疫或诱导耐受性，以及降低移植物的免疫原性或诱导保护。我们的长期目标是研究诱导供体器官免受 AVR 的保护。假设：细胞因子 IL-4 能够诱导针对猪内皮细胞 (EC) 异种损伤的广泛保护，并可用于制备 Xtr 器官，从而保护该器官免受 HAR 和 AVR 的侵害。具体目标。 I. 研究猪 EC 中 IL-4 诱导的针对异种激活的保护作用。将研究缺乏导致移植排斥的主要抗原的 EC 的激活反应，以了解 IL-1 的产生和 EC 激活的其他介质，并确定 IL-4 保护的要求和机制。二.描述参与防止补体杀伤的机制。 IL-4 诱导的保护需要信号蛋白 Akt 的参与。已知 Akt 可以激活多种可能产生保护作用的底物；因此，将对这些途径进行鉴定和表征。三．研究抗凋亡蛋白在 IL-4 诱导的细胞凋亡保护中的作用。将研究 Bcl-xL 和其他保护性分子在防止 TNF-α 和人类自然杀伤细胞引起的细胞凋亡方面的作用。在这前三个具体目标中，将使用激酶抑制剂研究保护途径，并使用 siRNA 定义候选蛋白的功能作用。四．在 Xtr 小鼠至大鼠模型中研究 IL-4 过表达对 HAR 和 AVR 的保护作用。该动物模型中的 AVR 过程与猪到灵长类动物模型中的类似，使我们能够定义保护机制。小鼠心脏将被携带IL-4基因的腺病毒或作为对照的不相关基因感染，然后移植到大鼠体内以研究移植物存活、组织学以及基因表达和激活。将在移植后的不同时期进行研究，以确定 IL-4 在预防激活表现和排斥反应病理过程中的功效。预计这种过程的强度会减弱并延迟，并且移植物存活会延长。实现这些目标将导致了解不同物种供体器官中 IL-4 的保护机制，以及它们在多大程度上有助于 Xtr 的成功，这对于那些没有人体器官的终末期器官衰竭患者至关重要可用的。公共卫生相关性用于移植的人体器官供应不足，克服这一短缺的一个潜在解决方案是异种移植（使用猪等供体动物的器官）。实现该提案的目标将定义一种修改临床异种移植供体器官的新方法。这也将为血管疾病（包括缺血和动脉粥样硬化）的新治疗提供知识。