TNF and rheumatoid arthritis: The combination of cytokines had no stronger effect than TNF alone in both PVNS and RA synoviocytes (PVNS cells: TNF/IL-17: 6.4 ± 1.0%, TNF/IL-17/GM-CSF: 8.1 ± 2.3% vs. 10.1 ± 2.2% for TNF alone; RA cells: TNF/IL-17: 13.2 ± 7.6%, TNF/IL-17/GM-CSF: 16.4 ± 10.3% vs. 15.8 ± 10.5% for TNF alone, Fig. 5).