The aim was to characterize the proteomic alterations in synovial fibroblasts from patients with juvenile idiopathic arthritis, with or without prior priming with inflamed synovial fluid. Synovial fibroblasts were isolated from the synovial fluid of patients with oligoarticular juvenile idiopathic arthritis via passaging. For the experiment, they were primed or not with a pool of 20% of pooled synovial fluid from patients for 48hrs.