Division of Rheumatology, Department of Internal Medicine, Chungnam National University Hospital, 282 Munhwaro, Daejeon 35015, Korea.
Research Institute for Medical Sciences, Chungnam National University School of Medicine, 266 Munhwaro, Daejeon 35015, Korea.
Int J Mol Sci. 2022 Feb 20;23(4):2342. doi: 10.3390/ijms23042342.
This study aimed to examine the role of CD70, which is highly expressed on fibroblast-like synoviocytes (FLS), in rheumatoid arthritis (RA) patients. FLS isolated from RA ( = 14) and osteoarthritis (OA, = 4) patients were stimulated with recombinant interleukin-17 (IL-17; 5 ng/mL) and tumor necrosis factor alpha (TNF-α; 5 ng/mL) for 24 h. Expression of CD70, CD27/soluble CD27 (sCD27), and hypoxia-inducible factor-2 alpha (HIF-2α) was analyzed by RT-qPCR, flow cytometry, and ELISA assays, respectively. Reactive oxygen species (ROS) expression and cell migration were also examined. The HIF-2α inhibitor PT-2385 and CD70 inhibitor BU69 were used to specifically suppress these pathways. Stimulation with IL-17 and TNF-α significantly induced CD70 expression in RA FLS. Although the synovial fluids from patients with RA contained high levels of sCD27, surface expression of CD27, a ligand of CD70, was rarely detected in RA FLS. Cytokine-induced CD70 expression was significantly decreased following antioxidant treatment. Following HIF-2α inhibition, RA FLS had decreased expression of CD70 and ROS levels. Migration of RA FLS was also inhibited by inhibition of CD70 or HIF-2α. The surface expression of CD70 is regulated by HIF-2α and ROS levels and is a key contributor to cytokine-enhanced migration in RA FLS.
本研究旨在探讨在类风湿关节炎（RA）患者中高度表达于成纤维样滑膜细胞（FLS）的 CD70 的作用。从 RA（=14）和骨关节炎（OA，=4）患者中分离的 FLS 用重组白细胞介素-17（IL-17；5ng/mL）和肿瘤坏死因子-α（TNF-α；5ng/mL）刺激 24 小时。通过 RT-qPCR、流式细胞术和 ELISA 检测分别分析 CD70、CD27/可溶性 CD27（sCD27）和缺氧诱导因子-2α（HIF-2α）的表达。还检查了活性氧（ROS）表达和细胞迁移。使用 HIF-2α抑制剂 PT-2385 和 CD70 抑制剂 BU69 特异性抑制这些途径。IL-17 和 TNF-α 的刺激显著诱导 RA FLS 中 CD70 的表达。尽管 RA 患者的滑膜液中含有高水平的 sCD27，但在 RA FLS 中很少检测到 CD70 的配体 CD27 的表面表达。抗氧化剂处理后，细胞因子诱导的 CD70 表达显著降低。抑制 HIF-2α 后，RA FLS 中 CD70 和 ROS 水平的表达降低。CD70 或 HIF-2α 的抑制也抑制了 RA FLS 的迁移。CD70 的表面表达受 HIF-2α 和 ROS 水平的调节，是细胞因子增强 RA FLS 迁移的关键因素。
