IL17A and rheumatoid arthritis: In the presence of IL-17, IL-17RA or IL-17RC RNA interference significantly enhanced SNP 0.1 μM induced apoptosis in RA FLS, with a 3 or 2.7 fold increase in apoptosis respectively compared to sicontrol (Figure 3C, P<0.05), confirming a protective effect of IL-17 on RA FLS apoptosis.