Identification of a complex between fibronectin and aggrecan G3 domain in synovial fluid of patients with painful meniscal pathology
Objectives: We previously described a panel of four cytokines biomarkers in knee synovial fluid for acute knee pain associated with meniscal pathology. The cytokine biomarkers included interferon gamma (IFN-γ), interleukin 6 (IL-6), monocyte chemotactic protein 1 (MCP-1), and macrophage inflammatory protein-1 beta (MIP-1β). Validation studies using other immunologic techniques confirmed the presence of IL-6, MCP-1 and MIP-1β, but not IFN-γ. Therefore we sought the identity of the IFN-γ signal in synovial fluid. Methods: Knee synovial fluid was collected from patients with an acute, painful meniscal injury, as well as asymptomatic volunteers. A combination of high-pressure chromatography, mass spectrometry and immunological techniques were used to enrich and identify the protein components representing the IFN-γ signal. Results: A protein complex of fibronectin and the aggrecan G3 domain was identified in the synovial fluid of patients with a meniscal tear and pain that was absent in asymptomatic controls. This protein complex correlated to the IFN-γ signal. A novel enzyme-linked immunosorbent assay (ELISA) was developed to specifically identify the complex in synovial fluid. Conclusions: We have identified a protein complex of fibronectin and aggrecan G3 domain that is a candidate biomarker for pain associated with meniscal injury. © 2010 The Canadian Society of Clinical Chemists.
Digital Object Identifier (DOI)
Scuderi, Gaetano J.; Woolf, Naruewan; Dent, Kaitlyn; Golish, S. Raymond; Cuellar, Jason M.; Cuellar, Vanessa G.; Yeomans, David C.; Carragee, Eugene J.; Angst, Martin S.; Bowser, Robert; and Hanna, Lewis S., "Identification of a complex between fibronectin and aggrecan G3 domain in synovial fluid of patients with painful meniscal pathology" (2010). Neurobiology. 572.