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Isolation and Culture of Primary Synovial Macrophages and Fibroblasts from Murine Arthritis Tissue
Published on: February 24, 2023
Expression and citrullination of keratin in synovial tissue of rheumatoid arthritis
Xiaotian Chang1, Xiangdong Jian, Xinfeng Yan
1Key Laboratory for Bio-Drugs of Ministry of Health, Research Center for Medicinal Biotechnology, Shandong Academy of Medical Sciences, 250062 Jinan, Shandong, People's Republic of China. changxt@sdams.cn
Abstract:
Keratin is the main component of cellular intermediate filaments, and its post-translational modification plays an important role in cell differentiation and apoptosis, as well as disease states. The conversion of peptidylarginine to citrulline, termed citrullination, is particularly involved in the pathogenesis of rheumatoid arthritis (RA). Immunohistochemistry using an antibody mixture that broadly recognized various keratin forms detected cytokeratin in many cells in the area lining the synovial membrane of RA. Furthermore, double immuno-florescent labeling showed that the cells expressing cytokeratin were also positive for citrulline when they were in the vicinity of extracellular deposits or approached the exterior of the synovial membrane. Western blot analysis demonstrated citrullination of keratin purified from RA synovial tissue by immuno-precipitation. The above results indicate the presence of citrullinated cytokeratin in synovial membranes in RA.
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