BACKGROUND: Gremlin-1, a bone morphogenetic protein (BMP) antagonist, is up-regulated in osteoarthritis (OA). Therefore, we aim to evaluate the correlation between gremlin-1 concentrations and the onset and severity of OA.

MATERIAL AND METHODS: We performed this cross-sectional study in a population of 212 patients with knee OA and 125 healthy controls.

RESULTS: Patients with knee OA had higher serum gremlin-1 concentrations than healthy controls. Serum and synovial fluid (SF) gremlin-1 concentrations increased according to advanced Kellgren-Lawrence grading stages.

CONCLUSIONS: Serum and SF gremlin-1 concentrations are correlated with the onset and severity of knee OA.

Keywords: Biomarkers - blood, Case-Control Studies, Cross-Sectional Studies, Intercellular Signaling Peptides and Proteins - metabolism, Osteoarthritis, Knee - metabolism, Severity of Illness Index, Synovial Fluid - metabolism