IL-6 trans-signalling directly induces RANKL on fibroblast-like synovial cells and is involved in RANKL induction by TNF-α and IL-17
IL-6 trans-signalling directly induces RANKL on fibroblast-like synovial cells and is involved in RANKL induction by TNF-α and IL-17
复制标题
DOI：
10.1093/rheumatology/ken363
复制
发表时间：
2008-11-01
期刊：
影响因子：
5.5
通讯作者：
Mihara, M.
中科院分区：
文献类型：
--
作者：
Hashizume, M.;Hayakawa, N.;Mihara, M.
目标。探讨细胞因子对RA患者成纤维样滑膜细胞RANKL表达的影响。用IL-6、TNF-α、IL-17、IL-1β和sIL-6R刺激RA-FLS 24 h，用实时荧光定量PCR、免疫印迹和免疫印迹法检测RANKL的表达。在增殖实验中，RA-FLS与细胞因子共同培养3d。将RA-FLS与原始细胞在IL-6/sIL-6R存在下共培养3d，检测原始细胞中NFATc1mRNA的表达。在IL-6/sIL-6R存在的条件下，将RA-FLS与PAR或PD98059(丝裂原活化蛋白激酶抑制剂)共同培养，观察其对RANKL表达及STAT3、ERK1/2磷酸化的影响。IL-6/sIL-6R(但不是单独的IL-6)和IL-1β诱导RANKL表达。另一方面，尽管TNF-α、IL-17或IL-1β刺激细胞生长和IL-6的产生，但它们并不诱导RANKL的表达。但在sIL-6R存在下，肿瘤坏死因子-α或IL-17可诱导RANKL的表达。通过与RA-FLS共培养，可诱导原始细胞表达NFATc1。IL-6/sIL-6R诱导RA-FLS中STAT3和ERK1/2的磷酸化，并分别被PAR和PD完全抑制。PAR可完全抑制IL-6/sIL-6R诱导的RANKL表达，而PD则不能。IL-6/sIL-6R可直接诱导RA-FLS中RANKL的表达，在肿瘤坏死因子-α和IL-17诱导RANKL中起重要作用。此外，IL-6/sIL-6R诱导的RANKL是通过Janus激酶/STAT信号通路介导的。
Objectives. We investigated the influence of cytokines on the expression of RANK ligand (RANKL) in fibroblast-like synoviocytes from RA patients (RA-FLS).Methods. RA-FLS were stimulated by IL-6, TNF-alpha, IL-17 and IL-1 beta with or without soluble IL-6 receptor (sIL-6R) for 24 h. The expression of RANKL was measured by real-time PCR, western blotting and immunostaining. In proliferation assay, RA-FLS were cultured with cytokines for 3 days. RA-FLS were co-cultured with RAW cell in the presence of IL-6/sIL-6R for 3 days and then NFATc1 mRNA expression in RAW cells was examined. RA-FLS was cultured with parthenolide [PAR, signal transducer and activator of transcription (STAT) inhibitor] or PD98059 (PD, mitogen-activated protein kinase inhibitor) in the presence of IL-6/sIL-6R and then the influence of these drugs on phosphorylation of STAT3 and ERK1/2, and RANKL expression was examined.Results. RANKL expression was induced by IL-6/sIL-6R (but not IL-6 alone) and by IL-1 beta. On the other hand, TNF-alpha and IL-17 did not induce RANKL expression, although TNF-alpha, IL-17 or IL-1 beta stimulated cell growth and IL-6 production. However, in the presence of sIL-6R, TNF-alpha or IL-17 induced RANKL expression. By the co-culture of RA-FLS, NFATc1 mRNA expression was induced in RAW cells. Finally, IL-6/sIL-6R induced phosphorylation of STAT3 and ERK1/2 in RA-FLS, and was completely inhibited by PAR and PD, respectively. PAR completely inhibited IL-6/sIL-6R-induced RANKL expression, but PD did not.Conclusions. IL-6/sIL-6R directly induced RANKL expression in RA-FLS and it is essential for RANKL induction by TNF-alpha and IL-17. Moreover, RANKL induction by IL-6/sIL-6R is mediated by the janus kinase/STAT signalling pathway.