title: Increased level of YKL-40 in sera from patients with early rheumatoid arthritis: a new marker for disease activity.
abstract: YKL-40 is a newly discovered major secretory protein of human chondrocytes and synoviocytes. We measured serum levels of YKL-40 in 52 patients with early onset rheumatoid arthritis (RA) by enzyme-linked immunosorbent assay (ELISA) during a 2-year prospective follow-up, correlating values with laboratory and clinical variables and radiographic progression. Levels at baseline before antirheumatic therapy were significantly higher in patients than in healthy controls. The levels of YKL-40 correlated with laboratory and clinical markers of disease activity both at baseline and during follow-up. Baseline YKL-40 values correlated with baseline Larsen scores but did not predict radiographic progression. Baseline and mean YKL-40 values did not differ between fast and slow radiological progressions. Mean YKL-40 levels correlated with the number of swollen joints but were not predictors of radiographic progression. These results suggest that in early RA, serum YKL-40 is an inflammatory marker correlating with disease activity. However, its levels do not predict clinical course or radiographic progression.
authors.affiliation: Department of Medicine, Helsinki University Central Hospital, Finland. Ritva.Peltomaa@hus.fi
authors.forename: R
authors.initials: R
authors.lastname: Peltomaa
authors.forename: L
authors.initials: L
authors.lastname: Paimela
authors.forename: S
authors.initials: S
authors.lastname: Harvey
authors.forename: T
authors.initials: T
authors.lastname: Helve
authors.forename: M
authors.initials: M
authors.lastname: Leirisalo-Repo
mesh_terms: D054392:Adipokines; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001172:Arthritis, Rheumatoid / Q000097:blood* / Q000000981:diagnostic imaging / Q000503:physiopathology; D001175:Arthrography; D015415:Biomarkers; D000071451:Chitinase-3-Like Protein 1; D018450:Disease Progression; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006023:Glycoproteins / Q000097:blood*; D006801:Humans; D007596:Joints / Q000473:pathology; D037102:Lectins; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012720:Severity of Illness Index; D013997:Time Factors
chemical_list: D054392:Adipokines; D015415:Biomarkers; C084533:CHI3L1 protein, human; D000071451:Chitinase-3-Like Protein 1; D006023:Glycoproteins; D037102:Lectins