Mullan Ronan H, Bresnihan Barry, Golden-Mason Lucy, Markham Trevor, O'Hara Rosemary, FitzGerald Oliver, Veale Douglas J, Fearon Ursula
Dept. of Rheumatology, Education and Research Centre, St. Vincent's University Hospital, Elm Park, Dublin 4, Ireland.
Arthritis Rheum. 2006 Jan;54(1):105-14. doi: 10.1002/art.21518.
To examine the role of the acute-phase protein serum amyloid A (A-SAA) in regulating cell adhesion molecule expression, leukocyte recruitment, and angiogenesis in rheumatoid arthritis (RA).
Intercellular adhesion molecule 1 (ICAM-1), vascular cell adhesion molecule 1 (VCAM-1), and matrix metalloproteinase 1 (MMP-1) expression was examined in RA fibroblast-like synoviocytes (FLS) and human microvascular endothelial cells (HMVECs) using flow cytometry and enzyme-linked immunosorbent assay techniques. Peripheral blood mononuclear cell (PBMC) adhesion to FLS/HMVECs was determined by flow cytometry. Angiogenesis was examined using a Boyden chemotaxis chamber and Matrigel tubule formation. NF-kappaB/IkappaBalpha mediation of the effects of A-SAA was investigated using a specific NF-kappaB inhibitor and Western blotting.
A-SAA significantly enhanced the time- and dose-dependent expression of ICAM-1 and VCAM-1 as effectively as interleukin-1beta/tumor necrosis factor alpha. A-SAA promoted the adhesion of PBMCs to FLS and HMVECs. In addition, A-SAA at 10 mug/ml and 50 mug/ml significantly increased endothelial cell tube formation by 69% and 207%, respectively. At 50 mug/ml and 100 mug/ml, A-SAA increased HMVEC migration by 188 +/- 54% and 296 +/- 71%, respectively (mean +/- SEM). A-SAA-induced expression of VCAM-1, ICAM-1, and MMP-1 was down-regulated by NF-kappaB inhibition. Furthermore, A-SAA induced IkappaBalpha degradation and NF-kappaB translocation, suggesting that its proinflammatory effects are mediated in part by NF-kappaB signaling.
Our findings demonstrate the ability of A-SAA to induce adhesion molecule expression, angiogenesis, and matrix degradation, mechanisms that are mediated by NF-kappaB. Targeting A-SAA and its signaling pathways may represent a new therapeutic approach in the treatment of RA.
研究急性期蛋白血清淀粉样蛋白A（A-SAA）在类风湿关节炎（RA）中调节细胞黏附分子表达、白细胞募集和血管生成的作用。
采用流式细胞术和酶联免疫吸附测定技术，检测RA成纤维样滑膜细胞（FLS）和人微血管内皮细胞（HMVECs）中细胞间黏附分子1（ICAM-1）、血管细胞黏附分子1（VCAM-1）和基质金属蛋白酶1（MMP-1）的表达。通过流式细胞术测定外周血单核细胞（PBMC）与FLS/HMVECs的黏附。使用博伊登趋化室和基质胶小管形成实验检测血管生成。使用特异性NF-κB抑制剂和蛋白质印迹法研究A-SAA作用的NF-κB/IκBα介导机制。
A-SAA能像白细胞介素-1β/肿瘤坏死因子α一样，显著增强ICAM-1和VCAM-1的时间和剂量依赖性表达。A-SAA促进PBMC与FLS和HMVECs的黏附。此外，10μg/ml和50μg/ml的A-SAA分别使内皮细胞管形成显著增加69%和207%。在50μg/ml和100μg/ml时，A-SAA分别使HMVEC迁移增加188±54%和296±71%（平均值±标准误）。NF-κB抑制可下调A-SAA诱导的VCAM-1、ICAM-1和MMP-1表达。此外，A-SAA诱导IκBα降解和NF-κB易位，表明其促炎作用部分由NF-κB信号介导。
我们的研究结果表明A-SAA具有诱导黏附分子表达、血管生成和基质降解的能力，这些机制由NF-κB介导。靶向A-SAA及其信号通路可能代表一种治疗RA的新方法。
