title: Serum level of osteopontin as an inflammatory marker does not indicate disease activity or responsiveness to therapeutic treatments in patients with rheumatoid arthritis.
abstract: Osteopontin (OPN) is known to be significantly involved in the pathogenesis of rheumatoid arthritis (RA). This study aimed to evaluate if the serum concentration of OPN in patients with RA before and after therapeutic treatments was correlated to disease activity and response to therapy. Blood samples from 40 patients with RA were collected at baseline and six months after starting treatment with disease-modifying antirheumatic drugs (DMARDs) and/or tumor necrosis factor (TNF)-α blockers. Serum levels of OPN were measured by ELISA. At baseline, the serum OPN level in RA patients was significantly higher than that of the healthy group. The OPN level at baseline in RA patients with severe disease activity as evaluated by DAS28 was slightly higher than that of those with moderate disease activity. The serum OPN level in RA patients was not significantly correlated with the DAS28 level. The serum OPN level in both responders and non-responders after therapy was significantly decreased regardless of responsiveness to therapy. Also, the OPN level at baseline did not affect the responsiveness to therapeutic treatments. In conclusion, serum OPN level was not correlated with disease activity or responsiveness of RA patients to therapeutic treatments.
authors.affiliation: East-West Bone & Joint Research Institute, Kyung Hee University, 149 Sangil-dong, Gangdong-gu, Seoul, 134-727, Republic of Korea.
authors.forename: Hye-In
authors.initials: HI
authors.lastname: Ji
authors.forename: Sang-Hoon
authors.initials: SH
authors.lastname: Lee
authors.forename: Ran
authors.initials: R
authors.lastname: Song
authors.forename: Hyung-In
authors.initials: HI
authors.lastname: Yang
authors.forename: Yeon-Ah
authors.initials: YA
authors.lastname: Lee
authors.forename: Seung-Jae
authors.initials: SJ
authors.lastname: Hong
authors.forename: Somi
authors.initials: S
authors.lastname: Kim
authors.forename: Yong-Beom
authors.initials: YB
authors.lastname: Park
authors.forename: Soo-Kon
authors.initials: SK
authors.lastname: Lee
authors.forename: Myung Chul
authors.initials: MC
authors.lastname: Yoo
authors.forename: Kyoung Soo
authors.initials: KS
authors.lastname: Kim
mesh_terms: D000328:Adult; D018501:Antirheumatic Agents / Q000627:therapeutic use; D001172:Arthritis, Rheumatoid / Q000097:blood* / Q000188:drug therapy; D015415:Biomarkers / Q000097:blood; D005260:Female; D006801:Humans; D007249:Inflammation / Q000097:blood; D008297:Male; D008875:Middle Aged; D053495:Osteopontin / Q000097:blood*; D012720:Severity of Illness Index
chemical_list: D018501:Antirheumatic Agents; D015415:Biomarkers; D053495:Osteopontin