ACAN and rheumatoid arthritis: Thus, the increase in serum levels of the CS846 epitope with significant reduction of the AGC, ADAMTS-4 and ADAMTS-5 levels and ADAMTS/TIMP-3 ratios under anti-TNF-α treatment indicates a shift of aggrecan turnover towards its synthesis, which may represent an important mechanism for preventing future joint damage and disability in RA patients.