IL-17 in synovial tissue and synovial fluid. (A) Number of IL-17+ cells in synovial tissue of ACPA- and ACPA+ RA and OA patients. The results are expressed as the number of cells assessed in 10 high-power fields at ×400 magnification. (B) Levels of IL-17 in synovial fluid determined by ELISA. *P < 0.05 and **P < 0.01, both indicating statistically significant differences. ACPA, anticitrullinated protein antibody; OA, osteoarthritis; RA, rheumatoid arthritis.
Suurmond et al. Arthritis Research & Therapy 2011 13:R150 doi:10.1186/ar3466