Department of Internal Medicine II, Fukushima Medical University School of Medicine, Hikarigaoka, Fukushima, Japan.
J Rheumatol. 2010 Apr;37(4):704-10. doi: 10.3899/jrheum.090582. Epub 2010 Feb 15.
To measure concentrations of the thrombin-cleaved isoform of osteopontin (OPN) in urine and plasma of patients with rheumatoid arthritis (RA), and to assess whether levels of thrombin-cleaved OPN are associated with measures of RA.
Subjects comprised 70 patients with RA, 20 patients with osteoarthritis (OA), and 46 healthy controls. RA disease activity was evaluated by tender joint count, swollen joint count, patient's global assessment of disease activity, erythrocyte sedimentation rate (ESR), and levels of C-reactive protein (CRP), matrix metalloproteinase-3 (MMP-3), and rheumatoid factor (RF), as well as 28-joint count Disease Activity Score (DAS28). OPN levels in plasma and urine were measured by ELISA.
Median levels of thrombin-cleaved OPN in urine (U-half) were significantly higher in RA patients (143.5 pmol/mmol Cr) than in healthy controls (67.9 pmol/mmol Cr) or OA patients (69.8 pmol/mmol Cr). Thrombin-cleaved OPN was not detected in plasma. U-half levels correlated significantly with levels of CRP (r = 0.26, p = 0.03), ESR (r = 0.26, p = 0.03), and RF (r = 0.28, p = 0.03). Median U-half levels were significantly higher in patients with stage III (249.9 pmol/mmol Cr) and IV (251.6 pmol/mmol Cr) disease than in patients with stage I (98.6 pmol/mmol Cr) disease.
Our results suggest that urine levels of the thrombin-cleaved isoform of OPN may reflect the severity of active inflammatory arthritis in patients with RA.
测量尿和血浆中骨桥蛋白（OPN）被凝血酶裂解的同种型（OPN）的浓度，并评估凝血酶裂解的 OPN 水平是否与 RA 的测量值相关。
研究对象包括 70 例 RA 患者、20 例骨关节炎（OA）患者和 46 名健康对照者。通过压痛关节计数、肿胀关节计数、患者对疾病活动的总体评估、红细胞沉降率（ESR）和 C 反应蛋白（CRP）、基质金属蛋白酶-3（MMP-3）和类风湿因子（RF）的水平以及 28 关节疾病活动评分（DAS28）评估 RA 疾病活动。通过 ELISA 法测定尿和血浆中的 OPN 水平。
RA 患者尿中（U 半）凝血酶裂解的 OPN 中位数水平（143.5 pmol/mmol Cr）明显高于健康对照组（67.9 pmol/mmol Cr）或 OA 患者（69.8 pmol/mmol Cr）。血浆中未检测到凝血酶裂解的 OPN。U 半水平与 CRP（r = 0.26，p = 0.03）、ESR（r = 0.26，p = 0.03）和 RF（r = 0.28，p = 0.03）显著相关。III 期（249.9 pmol/mmol Cr）和 IV 期（251.6 pmol/mmol Cr）患者的 U 半中位数水平明显高于 I 期（98.6 pmol/mmol Cr）患者。
我们的结果表明，尿中 OPN 凝血酶裂解同种型的水平可能反映了 RA 患者活动性炎症性关节炎的严重程度。
