摘要目的 研究血清淀粉样蛋白A(SAA)通过B类l型清道夫受体(SR-B1)途径对RA血管新生的作用.方法 取RA及OA患者的关节滑膜组织切片行免疫组织化学染色,观察SR-B1在关节滑膜中的表达及组织定位.选用人脐静脉内皮细胞(HUVECs),免疫荧光技术检测SR-B1在内皮细胞上的表达;细胞划痕实验和体外细胞管腔形成实验评估在SAA刺激下、SR-B1受体阻断/不阻断时对内皮细胞迁移及管腔形成能力的影响.采用t检验及单因素方差分析进行统计学分析.结果 ①与OA对照组(积分A值6 788±819)相比,RA患者关节滑膜组织中SR-B1呈显著高表达(积分A值31 849±6 977,t=3.567,P＜0.01),且在血管内皮细胞及血管周围区域可见较强阳性染色.②内皮细胞表面SR-B1高表达.③与空白对照组(迁移指数1.00±0.09)相比,SAA可促进血管内皮细胞迁移(迁移指数2.50±0.17,q=14.38,P＜0.01);应用抗体阻断SR-B1受体后内皮细胞迁移能力显著降低(迁移指数1.16±0.14和SAA组,q=13.02,P＜0.01).④与空白对照组(分支节点数6.6±0.8)相比,SAA可促进内皮细胞形成分枝状毛细管样管腔结构(分支节点数19.0±1.1,q=25.04,P＜0.01);阻断SR-B1后内皮细胞管腔形成能力被显著抑制(分支节点数7.6±1.3和SAA组,q=23.32,P＜0.01).结论 SAA可通过与SR-B1结合进而促进RA关节部位的血管新生.

abstractsObjective To investigate the role of scavenger receptor class B type 1 (SR-B1) signaling pathway in serum amyloid A (SAA)-induced angiogenesis in rheumatoid arthritis (RA).Methods The expression and location of SR-B1 in RA and osteoarthritis (OA) synovial tissues were observed by immunohistochemistry.And SR-B1 expression in the resting human umbilical vein endothelial cells (HUVECs) was detected by immunoflourescence.Wound repair assessement and tube formation assessement were employed to evaluate the effect on cell migration and tube formation stimulated by SAA and/or anti-SR-B1 antibody.The t-test and one-way analysis of variance (ANOVA) were used for statistical analysis.Results ① SR-B1 was significantly highly expressed in RA tissue samples (A=6 788±819) when compared to the minimal expression in OA (A =31 849±6 977,t=3.567,P＜0.01).Positive staining of SR-B1 was observed in RA synovial vascular endothelial cells and perivascular areas.② Strong staining for SR-B1 was observed in all HUVECs tested.③ Significant wound healing induced by SAA (MI=2.50±0.17) was found compared with the untreated controls (MI=1.00±0.09,q=14.38,P＜0.01),and the effects were inhibited in the presence of anti-SR-B1 antibody (MI=1.16±0.14,q=13.02,P＜0.01).④ Compared to the untreated group (branch point number:6.6±0.8),there was an enhanced formation of branched and capillary-hke tube structure followed by SAA stimulation (branch point number:19.0±1.1,q=25.04,P＜0.01) after culturing for 72 h,whereas,tube formation decreased markedly upon pre-treated with anti-SR-B1 antibody (branch point number:7.6±1.3,vs SAA,q =23.32,P＜0.01).Conclusion Our present study suggests that serum amyloid A may induce angiogenesis via SR-B1 signaling pathway in RA.