Objective: To investigate complement(C) factors(F) and their activation fragments expression in OA joint tissues.
Design: Immunohistochemistry and quantitative imaging were performed to analyze C3, C4, and CF (factor) B expression on osteochondral biopsies (43 patients) collected during arthroplasty. Isolated chondrocytes and synoviocytes, cartilage and synovial tissues obtained from surgical specimens of OA patients (15 patients) were cultured with or without IL-1β. Real time PCR for CFB, C3, and C4 was performed. Culture supernatants were analyzed for C3a, C5a, CFBa, and terminal complement complex (TCC) production.
Results: In osteochondral biopsies, C factor expression was located in bone marrow, in a few subchondral bone cells and chondrocytes. C3 was the most expressed while factor C4 was the least expressed factor. Gene expression showed that all C factors analyzed were expressed both in chondrocytes and synoviocytes. In chondrocyte cultures and cartilage explants, CFB expression was significantly higher than C3 and C4. Furthermore, CFB, but not C3 and C4 expression was significantly induced by IL-1β. As to C activation factors, C3a was the most produced and CFBa was induced by IL-1β in synovial tissue. TCC production was undetectable in isolated chondrocytes and synoviocytes cell culture supernatants, whereas it was significantly augmented in cartilage explants.
Conclusion: C factors were locally produced and activated in OA joint with the contribution of all tissues (cartilage, bone, and synovium). Our results support the involvement of innate immunity in OA and suggest an association between some C alternative pathway component and joint inflammation.
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http://dx.doi.org/10.3389/fimmu.2020.535010 | DOI Listing |
Exp Cell Res
January 2025
Translational Matrix Biology, University of Cologne, Medical Faculty, Cologne, Germany. Electronic address:
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Department of Biomedical Sciences, Chonnam National University Medical School, Hwasun 58128, Jeollanam-do, Republic of Korea.
Inflammatory disorders encompass a range of conditions, including osteoarthritis (OA), characterized by the body's heightened immune response to diverse stimuli. OA is a prevalent degenerative joint disease characterized by the progressive deterioration of joint cartilage and subchondral bone, leading to pain, limited mobility, and physical disability. Synovitis, the inflammation of the synovial membrane, is increasingly recognized as a critical factor in OA pathogenesis and progression.
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Department of Genetics and Cell Biology, School of Basic Medicine, Qingdao University, Qingdao, China.
Osteoarthritis (OA) is a chronic, degenerative joint disease primarily characterised by damage to the articular cartilage, synovitis and persistent pain, and has become one of the most common diseases worldwide. In OA cartilage, various forms of cell death have been identified, including apoptosis, necroptosis and autophagic cell death. Ever-growing observations indicate that ferroptosis, a newly-discovered iron-dependent form of regulated cell death, is detrimental to OA occurrence and progression.
View Article and Find Full Text PDFBMC Vet Res
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Department of Clinical Studies-New Bolton Center, University of Pennsylvania, 382 West Street Road, Kennett Square, PA, 19348, USA.
Osteoarthritis (OA) remains a challenging joint disorder necessitating effective anti-inflammatory interventions. In this study, our primary objective was to establish an in vitro protocol that replicates the clinical investigation of anti-inflammatory drugs intended for OA management. Focusing on recombinant IL-10 (r.
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