1 Centre for Inflammatory Diseases, Department of Medicine, Monash University, Melbourne, VIC, Australia. 2 Monash Micro Imaging, Monash University, Melbourne, VIC, Australia. 3 Central Northern Adelaide Renal and Transplantation Service, Royal Adelaide Hospital, Adelaide, South Australia, Australia. 4 Department of Medicine, The University of Adelaide, Adelaide, South Australia, Australia. 5 Department of Nephrology, Monash Health, Clayton, Melbourne, VIC, Australia. 6 Department of Paediatric Nephrology, Monash Health, Clayton, Melbourne, VIC, Australia.
Transplantation. 2017 May;101(5):1013-1024. doi: 10.1097/TP.0000000000001427.
The healthy kidney contains an extensive population of renal mononuclear phagocytes (RMPs), with substantial phenotypic and functional diversity. However, how this diverse population is affected by ischemia-reperfusion injury (IRI), an obligate part of renal transplantation, is not yet well understood. The aim of this study was to characterize the phenotypic and functional alterations in RMPs induced by IRI.
Renal mononuclear phagocytes were studied 24 and 72 hours after 30 minutes of renal ischemia or sham operation. Kidneys were digested and the phenotypes of renal leukocyte populations were analyzed via flow cytometry. Multiphoton microscopy was used to image renal dendritic cells (DCs) in vivo using CD11c reporter mice. The capacity of renal DCs to present antigen was examined by assessment of proliferation of ovalbumin-specific T cells in rat insulin promoter-membrane-bound ovalbumin transgenic mice after sham or IRI procedures.
Ischemia-reperfusion injury induced influx of monocytes, DCs, macrophages, and neutrophils into the kidney. Classification of RMP subpopulations based on CD11b/CD11c expression demonstrated that the RMPs that increased in response to IRI were predominantly newly recruited monocyte-derived inflammatory DCs. In vivo multiphoton imaging of CD11c-EYFP mice revealed that intrarenal DCs exhibited increased number and activity of dendrites in the postischemic period. Ischemia-reperfusion injury also promoted DC-dependent cross-presentation of renal antigens to CD8 T cells in the draining lymph node.
In response to renal IRI, RMP populations are skewed toward those derived from inflammatory monocyte precursors. In addition, renal DCs undergo functional activation, increasing their capacity to activate antigen-specific CD8 T cells in renal draining lymph nodes.
健康的肾脏中含有大量的肾单核吞噬细胞（RMP），其具有显著的表型和功能多样性。然而，这种多样化的群体是如何受到缺血再灌注损伤（IRI）的影响的，IRI 是肾移植的必要组成部分，目前还不是很清楚。本研究旨在描述 IRI 诱导的 RMP 表型和功能改变。
在肾缺血 30 分钟或假手术后 24 和 72 小时研究肾单核吞噬细胞。通过流式细胞术分析肾脏白细胞群体的表型，使用 CD11c 报告小鼠对体内肾脏树突状细胞（DC）进行多光子显微镜成像。通过评估卵清蛋白特异性 T 细胞在大鼠胰岛素启动子-膜结合卵清蛋白转基因小鼠中的增殖，来检查肾 DC 提呈抗原的能力，该模型在 sham 或 IRI 手术后。
IRI 诱导单核细胞、DC、巨噬细胞和中性粒细胞流入肾脏。基于 CD11b/CD11c 表达对 RMP 亚群进行分类，表明对 IRI 反应增加的 RMP 主要是新募集的单核细胞来源的炎性 DC。体内多光子成像的 CD11c-EYFP 小鼠显示，在缺血后时期，肾内 DC 显示出树突数量和活性的增加。IRI 还促进了肾抗原在引流淋巴结中向 CD8 T 细胞的 DC 依赖性交叉呈递。
在肾 IRI 反应中，RMP 群体偏向于来源于炎性单核细胞前体的群体。此外，肾 DC 发生功能激活，增加其在肾引流淋巴结中激活抗原特异性 CD8 T 细胞的能力。
