Mechanisms of Acceptance in Mouse Renal Allografts

小鼠肾同种异体移植物的接受机制

• 批准号: 8462892
• 负责人: Robert B Colvin
• 金额: $ 41.18万
• 依托单位: MASSACHUSETTS GENERAL HOSPITAL
• 依托单位国家: 美国
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-05-15 至 2014-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8462892
• 关键词: Acute; Address; Allografting; Behavior; Blood Vessels; CD4 Positive T Lymphocytes; Cell Communication; Cell physiology; Cells; Characteristics; Chimerism; Clinical; Complement; Computer Assisted; Custom; Dendritic Cells; Dependence; Development; Diphtheria Toxin; Employee Strikes; Eragrostis; Event; Excision; Funding; Generations; Genotype; Goals; Heart; Human; Image; Immune response; Immunosuppression; Inbred BALB C Mice; Infiltration; Institution; Kidney; Kidney Transplantation; Lead; Life; Lymphoid; Measurement; Mediating; Mediator of activation protein; Minor Histocompatibility Antigens; Molecular; Motion; Mus; Neonatal; Nephrectomy; Organ; Organ Transplantation; Outcome; Pathologic; Pathologic Processes; Patients; Pharmaceutical Preparations; Phenotype; Physiology; Predisposition; Process; Production; Progress Reports; Protocols documentation; Regulatory T-Lymphocyte; Research Design; Role; Skin graft; System; T-Lymphocyte; Testing; Therapeutic; Time; Transplantation; Transplantation Tolerance; Tryptophan 2,3 Dioxygenase; Tubular formation; Video Recording; base; cell motility; cell type; chemokine; clinically relevant; cytokine; enzyme linked immunospot assay; follow-up; in vivo; insight; kidney allograft; latency-associated protein; novel; public health relevance; research study; trafficking

DESCRIPTION (provided by applicant): This proposal addresses the need for definitive evidence on the role of Foxp3+/T regulatory cells in the acceptance of physiologically relevant full MHC incompatible organ grafts in various settings of operational tolerance. In the initial year of funding (ARRA), spontaneous acceptance of MHC-mismatched mouse renal allografts was shown to depend exquisitely on Foxp3 cells using diphtheria toxin (DT) to transiently deplete circulating and intragraft Foxp3 cells in B6.Foxp3DTR mice bearing life sustaining DBA/2 renal allografts. The accepted grafts had distinctive nodular perivascular infiltrates of Foxp3 cells and dendritic cells (DC). Deletion of foxp3 cells caused dissolution of the nodular aggregates and widespread infiltration of the cortex, tubules and blood vessels by T cells, typical of acute rejection, and manifested by a rise in BUN over 7 days. Similar nodular aggregates of Foxp3 cells occur in grafts of patients who have accepted MHC mismatched kidneys on mixed chimerism tolerance induction protocols. Specific aim 1 will extend these observations to other forms of induced tolerance, mixed chimerism and neonatal tolerance, some of which are expected to be Foxp3 dependent; those with deletional mechanisms are expected to be Foxp3 independent. We will seek distinctive pathologic features in the graft, indicating Treg activity, such as the co-expression of latency associated protein (LAP) and Foxp3 or DC expression of indoleamine 2,3-dioxygenase (IDO), that might be used to distinguish foxp3 dependent from foxp3 independent forms of graft acceptance. The donor reactivity and regulatory potential of the cells in grafts and in lymphoid organs will be tested by ELISPOT and compared between the different forms of acceptance and acute rejection. The dependence of systemic tolerance on the intragraft infiltrates will be tested by graft nephrectomy in recipients with accepted kidney and skin grafts that have a remaining native kidney. Specific aim 2 will seek to identify the molecular and cellular basis for the dramatic strain differences in susceptibility to spontaneous graft acceptance, comparing BALB/c (rejected) and DBA/2 (accepted) kidneys (both H-2d) in B6 recipients. We will test for strain differences in DC function, cytokine/chemokine/complement mediators, minor histocompatibility antigens and ability to generate Foxp3 cells. Follow-up experiments seek to alter identified factors to promote acceptance of BALB/c kidneys. Specific aim 3 visualize interaction of Foxp3+ cells with other T cells, recipient and donor dendritic cells and tubular cells in accepting and rejecting renal grafts using a custom real time confocal, multiphoton endomicroscope. This system permits observations of the same graft over time, live video recording, delineation of 3-4 different cell types and computer assisted measurement of cell motility and interactions. These studies are designed to reveal the significance and in vivo function of Foxp3+ Treg in murine renal allograft acceptance and provide insights potentially applicable in clinical renal transplantation.

描述（由申请人提供）：该提案解决了对FOXP3+/T调节细胞在接受各种操作耐受环境中生理相关的完整MHC不兼容的器官移植物中的作用的确切证据。在资金的最初年份（ARRA）中，显示出使用白喉毒素（DT）的FOXP3细胞的MHC不匹配的小鼠肾脏同种异体移植物的自发接受，以瞬时耗尽循环和内部循环和内部的FOXP3细胞，在B6.foxp3dtr小鼠中持续持续持续dba/2肾脏Allogrogrografts。所接受的移植物具有独特的结节性结节性狐狸3细胞和树突状细胞（DC）。 FOXP3细胞的缺失导致结节骨料的溶解，并通过T细胞广泛渗透皮层，小管和血管，典型的急性排斥反应，并在BUN 7天内的升高表现出来。 Foxp3细胞的类似结节骨料发生在接受MHC不匹配的肾脏易粘性耐受性诱导方案的患者的移植物中。具体的目标1将把这些观察结果扩展到其他形式的诱导耐受性，混合嵌合和新生儿耐受性，其中一些预计将取决于FOXP3。那些具有缺失机制的人有望独立于FOXP3。我们将在移植物中寻求独特的病理特征，表明TREG活性，例如潜伏相关蛋白（LAP）的共表达和吲哚胺2,3-二氧酶（IDO）的FOXP3或DC表达，这些酶（IDO）可用于将FOXP3与FoxP3独立的嫁接形式区分开来。将通过ELISPOT测试移植物和淋巴器官中细胞的供体反应性和调节潜力，并比较不同形式的接受和急性排斥。全身性耐受性对授课内部浸润的依赖性将通过移植肾切除术在接受的肾脏和皮肤移植物的接受者中测试。具体目标2将寻求确定分子和细胞基础，以比较BALB/C（被拒绝）和DBA/2（接受的）肾脏（均为H-2D）在B6受体中比较BALB/C（被拒绝）和DBA/2（均为H-2D）。我们将测试DC功能，细胞因子/趋化因子/补体介质，较小的组织相容性抗原和产生FOXP3细胞的能力的应变差异。后续实验试图改变已确定的因素以促进BALB/C肾脏的接受。特定的目标3可视化FOXP3+细胞与其他T细胞，受体和供体的树突状细胞和管状细胞的相互作用，并使用自定义的实时共凝聚，多光元内内分镜接受和拒绝肾移植物。该系统允许随着时间的推移观察相同的移植物，实时视频记录，3-4种不同的细胞类型的描述以及计算机辅助测量细胞运动和相互作用。这些研究旨在揭示Foxp3+ Treg在鼠肾脏同种异体移植接受性中的显着性和体内功能，并提供可能适用于临床肾移植的见解。