Serum and synovial fluid chemokine ligand 2/monocyte chemoattractant protein 1 concentrations correlates with symptomatic severity in patients with knee osteoarthritis

Objective Serum and synovial fluid (SF) chemokine ligand 2 (CCL2)/monocyte chemoattractant protein 1 (MCP-1) concentrations have been identified to be increased in osteoarthritis (OA) patients. The scope of this study was to examine CCL2 concentrations in serum and SF of knee OA patients and to explore their association with patient-reported symptomatic severity. Method One hundred and sixty-one knee OA patients and 138 healthy controls were enrolled into the study from our hospital. We collected Western Ontario and McMaster Universities Arthritis Index (WOMAC) scores from OA patients and measured CCL2 concentrations in serum and SF using enzyme-linked immunosorbent assay method, and correlation between WOMAC scores and CCL2 concentrations were analysed. Results CCL2 concentrations in SF instead of serum were independently and positively associated with self-reported greater pain (r=0.460, P<0.001) and physical disability (r=0.561, P<0.001) in OA patients. Conclusion CCL2 in SF might serve as a novel and reliable biomarker for assessing symptomatic severity of OA.