Plasma and synovial fluid inflammatory cytokine profiles in primary knee osteoarthritis

Objective: The objective of this study is to compare inflammatory cytokine levels in primary knee osteoarthritis (OA) patients and healthy controls. Methods: A total of 32 knee OA patients and 14 healthy controls were enrolled. A multiplex immunoassay was utilized for 10 cytokines in plasma and synovial fluid. Results: Plasma IL-2, IL-4, and IL-6 concentrations were significantly greater in knee OA patients than controls. Moreover, both plasma IL-4 and IL-6 were positively correlated with the radiographic severity of knee OA. Conclusions: Plasma IL-4 and IL-6 may serve as biomarkers reflecting the severity of OA.