Department of Medicine, University of Virginia, Charlottesville, Virginia, USA.
J Clin Invest. 2012 Nov;122(11):3931-42. doi: 10.1172/JCI63170. Epub 2012 Oct 24.
DC-mediated NKT cell activation is critical in initiating the immune response following kidney ischemia/reperfusion injury (IRI), which mimics human acute kidney injury (AKI). Adenosine is an important antiinflammatory molecule in tissue inflammation, and adenosine 2A receptor (A₂AR) agonists protect kidneys from IRI through their actions on leukocytes. In this study, we showed that mice with A₂AR-deficient DCs are more susceptible to kidney IRI and are not protected from injury by A₂AR agonists. In addition, administration of DCs treated ex vivo with an A₂AR agonist protected the kidneys of WT mice from IRI by suppressing NKT production of IFN-γ and by regulating DC costimulatory molecules that are important for NKT cell activation. A₂AR agonists had no effect on DC antigen presentation or on Tregs. We conclude that ex vivo A₂AR-induced tolerized DCs suppress NKT cell activation in vivo and provide a unique and potent cell-based strategy to attenuate organ IRI.
在模拟人类急性肾损伤(AKI)的肾缺血/再灌注损伤(IRI)后,DC 介导的 NKT 细胞激活对于启动免疫反应至关重要。腺苷是组织炎症中的一种重要抗炎分子,腺苷 2A 受体(A₂AR)激动剂通过作用于白细胞来保护肾脏免受 IRI。在这项研究中,我们表明,缺乏 A₂AR 的 DC 的小鼠更容易发生肾 IRI,并且不能通过 A₂AR 激动剂来预防损伤。此外,用 A₂AR 激动剂处理的 DC 体外处理可通过抑制 NKT 细胞产生 IFN-γ和调节对 NKT 细胞激活很重要的 DC 共刺激分子来保护 WT 小鼠的肾脏免受 IRI。A₂AR 激动剂对 DC 抗原呈递或 Tregs 没有影响。我们得出结论,体外 A₂AR 诱导的耐受 DC 可抑制体内 NKT 细胞的激活,并提供一种独特且有效的基于细胞的策略来减轻器官 IRI。