RT Journal Article
SR Electronic
T1 Thrombin-cleaved Osteopontin Is Increased in Urine of Patients with Rheumatoid Arthritis
JF The Journal of Rheumatology
JO J Rheumatol
FD The Journal of Rheumatology
SP 704
OP 710
DO 10.3899/jrheum.090582
VO 37
IS 4
A1 KIORI SHIO
A1 HIROKO KOBAYASHI
A1 TOMOYUKI ASANO
A1 RIE SAITO
A1 HARUYO IWADATE
A1 HIROSHI WATANABE
A1 HIROFUMI SAKUMA
A1 TETSUYA SEGAWA
A1 MASAHIRO MAEDA
A1 HIROMASA OHIRA
YR 2010
UL http://www.jrheum.org/content/37/4/704.abstract
AB Objective. 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. Methods. 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. Results. 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. Conclusion. 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.