Department of Nephrology, Xuzhou, Jiangsu, China.
Department of Rheumatology and Immunology, Affiliated Hospital of Xuzhou Medical University, Xuzhou, Jiangsu, China.
Rheumatology (Oxford). 2019 Nov 1;58(11):2039-2050. doi: 10.1093/rheumatology/kez112.
We previously reported that ex vivo TGF-β and IL-2-induced CD8+CD103+ regulatory T cells (CD8+CD103+ iTregs) displayed similar immunosuppressive effect and therapeutic function on lupus mice nephritis to that of CD4+Foxp3+ Tregs. In view of the important role of glomerular endothelial cell (GEC) injury in inflammatory processes in SLE, this study aimed to investigate the nature and mechanism of CD8+CD103+ iTregs-mediated amelioration of LN by attenuating GEC injury.
Treg cells from patients with SLE and from healthy controls were characterized by flow cytometry analysis. The expression of pro-inflammatory mediators and VEGF were analysed in healthy controls, patients with SLE and MRL/lpr mice by ELISA, western blot, and real-time quantitative RT-PCR (qRT-PCR). Typical lesions of diffuse proliferative LN were observed in MRL/lpr mice through the use of haematoxylin and eosin, Masson, periodic acid-Schiff, periodic acid-Schiff methenamine, transmission electron microscopy and IF microscopy. Angiogenesis was analysed in GECs by cell investigating proliferation, migration, and tube formation.
The results revealed that the frequency of Treg cells was inversely correlated with the expression of VCAM-1 and ICAM-1 in patients with SLE. Furthermore, adoptive transfer of CD8+CD103+ iTregs to MRL/lpr mice was associated with decreased levels of autoantibodies and proteinuria, reduced renal pathological lesions, and lowered renal deposition of IgG/C3. We further found that CD8+CD103+ iTregs not only suppressed the expression of pro-inflammatory mediators but also attenuated GEC injury by promoting angiogenesis.
Our study has identified the role of CD8+CD103+ iTregs on attenuating GEC injury and provided a possible application of this new iTregs subset in lupus nephritis and other autoimmune diseases.
我们之前报道过，体外 TGF-β 和 IL-2 诱导的 CD8+CD103+调节性 T 细胞（CD8+CD103+ iTregs）对狼疮肾炎小鼠的免疫抑制作用和治疗功能与 CD4+Foxp3+Tregs 相似。鉴于肾小球内皮细胞（GEC）损伤在 SLE 炎症过程中的重要作用，本研究旨在探讨 CD8+CD103+ iTregs 通过减轻 GEC 损伤来改善 LN 的性质和机制。
通过流式细胞术分析来自 SLE 患者和健康对照者的 Treg 细胞。通过 ELISA、western blot 和实时定量 RT-PCR（qRT-PCR）分析健康对照者、SLE 患者和 MRL/lpr 小鼠中促炎介质和 VEGF 的表达。通过苏木精和伊红、Masson、过碘酸-Schiff、过碘酸-Schiff 甲胺、透射电子显微镜和 IF 显微镜观察 MRL/lpr 小鼠弥漫性增生性 LN 的典型病变。通过细胞增殖、迁移和管形成实验分析 GEC 中的血管生成。
结果表明，Treg 细胞的频率与 SLE 患者中 VCAM-1 和 ICAM-1 的表达呈负相关。此外，将 CD8+CD103+ iTregs 过继转移到 MRL/lpr 小鼠中与降低自身抗体和蛋白尿水平、减轻肾脏病理损伤以及降低 IgG/C3 在肾脏中的沉积有关。我们进一步发现，CD8+CD103+ iTregs 不仅抑制了促炎介质的表达，而且通过促进血管生成来减轻 GEC 损伤。
本研究确定了 CD8+CD103+ iTregs 在减轻 GEC 损伤中的作用，并为该新的 iTregs 亚群在狼疮肾炎和其他自身免疫性疾病中的应用提供了可能。
