Isobaric tag for relative and absolute quantitation-based proteomics analysis of synovial fluid from osteoarthritic knee / 中华风湿病学杂志

ABSTRACT

Objective We performed comprehensive proteomic analyses of synovial fluid by using the isobaric tags for relative and absolute quantitation (iTRAQ) method and LC-MS/MS, and searched for candidate biomarkers for osteoarthritis. Methods Synovial fluid was collected from patients with late-stage OA, earlystage OA and the control group. Molecular variations were detected by the iTRAQ method. T test was used for statistical analysis. Results Using the iTRAQ method, we identified 1 283 proteins from synovial fluid of patients with osteoarthritis, of which 268 proteins were not reported previously. There were 72 proteins upregulated and 249 proteins down-regulated between moderate OA group and controls. One hundred and twentyeight proteins were up-regulated and 141 proteins were down-regulated between severe OA group and controls.One hundred and ninety-two proteins were up-regulated and 76 proteins were down-regulated between severe OA group and moderate OA group. Eight proteins were found to be up-regulated in the three groups.Conclusion This is an in-depth analysis of the synovial fluid proteome from patients with osteoarthritis by iTRAQ method. The catalog of proteins generated in this study will further expand our knowledge regarding the pathophysiology of osteoarthritis and help us in identifying good biomarkers for early diagnosis.