Serum evaluation of synovial fluid biomarkers in osteoarthritis.

ObjectiveIn our previous study, we identified forty-seven differentially expressed proteins in the synovial fluid of osteoarthritis (OA) patients. Given that serum testing is less invasive and remains the first-line screening tool, this study aimed to explore whether these synovial fluid-derived protein candidates could be detected in serum and whether they might serve as translatable biomarkers for OA.MethodsUsing antibody array technology, we analyzed the expression levels of these forty-seven proteins in serum samples from forty OA patients and forty healthy controls.ResultsCompared to healthy individuals, seventeen proteins were significantly differentially expressed in the serum of OA patients, showing consistent trends with their levels in synovial fluid. Among these, LASSO regression analysis identified seven proteins including GITR L, Osteoactivin, BAFF, NT-4, PAI-1, EG-VEGF, and GROa, which had superior diagnostic and predictive properties for OA. These proteins demonstrated high sensitivity and specificity in ROC curve analysis and were significantly correlated with WOMAC and MOAKS scores. Notably, this study is the first to report abnormal levels of these seven proteins in the serum of OA patients.ConclusionOur findings suggest that these seven proteins may serve as novel serum biomarkers for OA, offering potential for improved diagnosis and disease monitoring.