Ex Vivo Nanoparticle Drug Delivery Targeted to Human Renal Allograft Endothelium

针对人肾同种异体移植物内皮的体外纳米颗粒药物输送

基本信息

批准号：
10155842
负责人：
JORDAN S POBER
金额：
$ 2.94万
依托单位：
YALE UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2017
资助国家：
美国
起止时间：
2017-07-01 至 2022-06-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10155842
关键词：
Acute Address Alleles Allografting Antibodies Antibody titer measurement Antibody-Producing Cells Antigen Targeting Antigens Arteries Binding Biochemical Blood Blood Vessels Blood capillaries Body Temperature Caliber Cell Culture Techniques Cells Chronic Clinical Clinical Trials Collaborations Complement Complement Activation Complement Membrane Attack Complex Data Deposition Development Dose Drug Delivery Systems Early Endosome Endothelial Cells Endothelium Erythrocytes Ethics Excision Funding Gamma globulin Genes Goals Graft Survival Grant HLA Antigens Harvest Histocompatibility Hour Human Immune Immunodeficient Mouse In Situ In Vitro Individual Inflammation Infusion procedures Injury Intervention Intravenous Intravenous Immunoglobulins Ischemia Kidney Kidney Failure Kidney Transplantation Leukocytes Mediating Membrane Proteins Methods Microfluidics Mus Organ Organ Harvestings Outcome PECAM1 gene Patients Perfusion Perioperative Pharmaceutical Preparations Plasmapheresis Polymers Population Postoperative Period Prevention Process Protective Agents Protein-Serine-Threonine Kinases Proteins Pump Reagent Recovery Research Resistance Risk Factors Signal Pathway Signal Transduction Small Interfering RNA T-Lymphocyte Testing Therapeutic Therapeutic Agents Time Transplant Recipients Transplantation Transplantation Surgery United States National Institutes of Health Universities Validation Vascular Endothelial Cell anti-endothelial cell antibody antibody conjugate base cell injury cell type cost drug candidate experimental study fluorophore gene product graft failure humanized mouse immunoregulation improved improved outcome in vivo inflammatory milieu inhibitor/antagonist kidney allograft kidney vascular structure mouse model nanomedicine nanoparticle nanoparticle delivery nanoparticle drug neutrophil novel strategies pre-clinical prevent recruit response small molecule small molecule therapeutics success targeted delivery targeted treatment

项目摘要

A significant proportion of patients with renal failure who would benefit from kidney transplantation are highly pre-sensitized, i.e. they have high titers of pre-formed circulating antibodies (Abs) reactive with 80% or more of non-self allelic forms of class I and/or class II HLA antigens called panel reactive Abs (PRA). Upon transplantation, host PRA will bind to graft HLA antigens that are highly expressed on graft endothelial cells (ECs) where they activate host human complement resulting in deposition of membrane attack complex (MAC) on the ECs. Human MAC does not lyse human ECs, but instead alters them to express gene products that promote inflammation. The inflammatory milieu favors activation of adaptive immune effectors at the expense of protective immunoregulation. Consequently, if transplanted, patients with high titer PRA have increased episodes of acute and chronic rejection resulting in more graft failure and graft loss. Current therapeutic approaches include plasmapheresis to reduce the titer of circulating PRA, targeted elimination of Ab-producing cells and/or administration of high doses of intravenous gamma globulin to reduce inflammation, but PRA titers return and these interventions have had only limited impact on outcomes. We propose a novel strategy to complement these approaches, namely to reduce the response of graft ECs to PRA/MAC by reducing expression of HLA antigen targets and/or by inhibiting PRA/MAC signaling in ECs. The latter approach is based upon our elucidation of the relevant signaling pathways. To accomplish this, we will develop safe, polymeric nanoparticles (NPs) that are targeted towards graft ECs by means of conjugated anti-EC Abs and use these NPs to deliver siRNAs or small molecule therapeutics (“drugs”) during a period of ex vivo normothermic perfusion (EVNP), an approach that is being applied to improve energy stores in kidneys and other organs from deceased donors prior to transplantation. The NPs, which will be bound to and internalized by the graft ECs, will then serve as a depot for sustained release of the therapeutic agent for a period sufficient to allow graft accommodation and/or host immunoregulation to develop. In Specific Aim 1, we will use human EC cultures and human artery segments interposed into the aortae of immunodeficient mice to identify the optimal siRNAs or drugs that can protect ECs from PRA. Our initial target will be prevention of Akt activation, a key step in PRA/MAC signaling. In Specific Aim 2, we will identify optimal Abs for targeting renal human ECs and use these to identify conditions for efficient pan-EC delivery in human kidneys unsuitable for clinical transplantation that are subjected to EVNP by our collaborators at the University of Cambridge. (U01 support will be used only for experiments and analyses conducted at Yale; the costs of experimental EVNP will be provided by our Cambridge colleagues who are supported by a grant from the UK National Institute for Health Research and experimental EVNP will be conducted at the University of Cambridge under their Ethics Approval.) If successful, this approach can be extended to other uses and could justify a human clinical trial.

相当大比例的肾衰竭患者可以从肾移植中受益预敏化，即它们具有高滴度的预形成循环抗体 (Ab)，可与 80% 或更多的 I 类和/或 II 类 HLA 抗原的非自身等位基因形式，称为面板反应性抗体 (PRA)。移植后，宿主 PRA 将与移植物内皮细胞上高表达的 HLA 抗原结合 (EC)，它们激活宿主人类补体，导致膜攻击复合物 (MAC) 沉积人类 MAC 不会裂解人类 EC，而是改变它们以表达基因产物炎症环境有利于适应性免疫效应器的激活，但代价是付出代价。经测试，如果进行移植，患者的高滴度 PRA 会增加。急性和慢性排斥反应导致更多的移植物失败和移植物损失。方法包括血浆置换以降低循环 PRA 的滴度、有针对性地消除产生抗体的抗体细胞和/或给予高剂量静脉注射丙种球蛋白以减少炎症，但 PRA 滴度返回，并且这些干预措施对结果的影响有限。我们提出了一种新颖的策略。这些方法，即通过减少移植补体 ECs 对 PRA/MAC 的反应后一种方法是通过抑制 EC 中 HLA 抗原靶标的表达和/或抑制 PRA/MAC 信号传导来实现。基于我们对相关信号通路的阐明，为了实现这一目标，我们将开发安全的、通过缀合抗 EC 抗体靶向移植 EC 的聚合物纳米粒子 (NP) 在离体期间使用这些 NP 来递送 siRNA 或小分子治疗药物（“药物”）常温灌注（EVNP），一种用于改善肾脏能量储存的方法移植前来自已故捐献者的其他器官，这些器官将被结合并内化。由移植ECs，然后将作为治疗剂在足够长的时间内持续释放的储存库为了使移植物适应和/或宿主免疫调节得以发展，在具体目标 1 中，我们将使用人类。将 EC 培养物和人类动脉片段插入免疫缺陷小鼠的主动脉中，以鉴定能够保护 EC 免受 PRA 影响的最佳 siRNA 或药物我们的最初目标是预防 Akt 激活，这是一种机制。在具体目标 2 中，我们将确定针对人类肾脏 EC 的最佳抗体。并利用这些来确定在不适合临床的人肾中有效泛 EC 递送的条件由我们在剑桥大学的合作者进行的移植（U01 支持）。仅用于在耶鲁大学进行的实验和分析；实验 EVNP 的费用为由我们的剑桥同事提供，他们得到了英国国家健康研究所的资助研究和实验 EVNP 将在剑桥大学按照其道德规范进行批准。）如果成功，这种方法可以扩展到其他用途，并可以证明人体临床试验的合理性。