When considering that the inflammatory activity in arthritis has been attributed to Th17 cells in the synovial fluid (101), as well as the number of Th17 cells in the serum of RA patients being positively correlated with the disease activity score in 28 joints (DAS28), anti-CCP antibody and C-reactive protein levels (102), the importance of interaction between Tregs and Th17 cells in RA becomes very apparent. Here, CRP is linked to rheumatoid arthritis.