TLR9 and rheumatoid arthritis: These differences were even more evident following stimulation with TLR ligands, where an increase in CD209/CD14+ DC expressing IL12 was observed in response to all TLR ligands in both RA and PsA vs HC, with a significant increase demonstrated for the TLR9 agonist CPG in PsA patients (p<0.05) and RA patients (p<0.01) (Figure 1D).