Department of Clinical Immunology, Sanjay Gandhi Postgraduate Institute of Medical Sciences, Lucknow, India.
J Rheumatol. 2011 Sep;38(9):1994-9. doi: 10.3899/jrheum.110058. Epub 2011 Jul 1.
Membrane-bound receptor for advanced glycation endproducts (mRAGE) is overexpressed in response to increasing concentrations of its ligand (e.g., S100A12) and triggers an inflammatory immune response. In contrast, soluble RAGE (sRAGE) acts as a decoy receptor and downmodulates inflammation. Decreased sRAGE levels are associated with autoimmune diseases; however, limited data are available in juvenile idiopathic arthritis (JIA). We studied sRAGE levels in patients with JIA [enthesitis-related arthritis (ERA) category].
sRAGE levels were estimated in the serum of patients with ERA JIA (n = 101), systemic-onset JIA and polyarticular JIA (n = 10 each), and healthy controls (n = 45). Synovial fluid (SF) sRAGE was measured in patients with ERA, rheumatoid arthritis, reactive arthritis, and osteoarthritis (n = 10). Levels of S100A12 were also measured. Twenty-four patients with ERA were followed for 4 months. Disease activity was assessed by swollen joint count (SJC), tender joint count (TJC), and erythrocyte sedimentation rate (ESR). All levels are expressed as median (range).
The serum sRAGE (pg/ml) level was significantly lower in patients compared to healthy controls [515 (64-1887) vs 1542 (627-3159); p < 0.0001]. In paired samples, SF had lower levels compared to corresponding plasma level [102 (51-799) vs 481 (134-1006); p < 0.0001]. The level of S100A12 (ng/ml) was higher in SF (1042; 573-1415) than serum (638; 208-779). Serum sRAGE correlated negatively with S100A12 levels (r = -0.474; p < 0.01.), ESR (r = -0.306; p < 0.01), and SJC (r = -0.237; p < 0.05), but not with TJC (r = -0.134; p = NS). The levels of sRAGE remained stable over time in patients with stable disease.
Levels of sRAGE are reduced in patients with ERA and correlate negatively with disease activity and S100A12 levels. sRAGE may be a modulator of inflammation in these patients.
膜结合型晚期糖基化终产物受体（mRAGE）在其配体（例如 S100A12）浓度增加时过度表达，并引发炎症免疫反应。相比之下，可溶性 RAGE（sRAGE）作为诱饵受体并下调炎症。sRAGE 水平降低与自身免疫性疾病有关；然而，幼年特发性关节炎（JIA）的相关数据有限。我们研究了 JIA [附着点相关关节炎（ERA）类别]患者的 sRAGE 水平。
估计了 101 例 ERA JIA 患者、10 例全身性 JIA 和多关节 JIA 患者和 45 例健康对照者的血清 sRAGE 水平。还测量了 10 例 ERA、类风湿关节炎、反应性关节炎和骨关节炎患者的关节液（SF）sRAGE。测量了 S100A12 的水平。对 24 例 ERA 患者进行了 4 个月的随访。通过肿胀关节计数（SJC）、压痛关节计数（TJC）和红细胞沉降率（ESR）评估疾病活动度。所有水平均以中位数（范围）表示。
与健康对照组相比，患者的血清 sRAGE（pg/ml）水平显著降低[515（64-1887）比 1542（627-3159）；p<0.0001]。在配对样本中，SF 中的水平低于相应的血浆水平[102（51-799）比 481（134-1006）；p<0.0001]。SF 中的 S100A12（ng/ml）水平高于血清[1042；573-1415]比血清[638；208-779]。血清 sRAGE 与 S100A12 水平（r=-0.474；p<0.01）、ESR（r=-0.306；p<0.01）和 SJC（r=-0.237；p<0.05）呈负相关，但与 TJC 无关（r=-0.134；p=NS）。在病情稳定的患者中，sRAGE 水平在一段时间内保持稳定。
ERA 患者的 sRAGE 水平降低，与疾病活动度和 S100A12 水平呈负相关。sRAGE 可能是这些患者炎症的调节剂。
