TNC and rheumatoid arthritis: ACPAs are produced locally within the RA joint and may contribute directly to disease pathogenesis.53 For example immune complexes containing cFib stimulate cytokine synthesis in macrophages via activation of Fcγ-receptor and TLR417 and, due to the homology of fibrinogen and the FBG domain of tenascin-C, it is conceivable that immune complexes containing cTNC may contribute to disease pathogenesis through a similar mechanism.