Fig. 6

Intracellular cytokine expression in monocyte subsets from rheumatoid arthritis (RA) patients following toll-like receptor 9 (TLR9) stimulation. Mononuclear cells from RA patients and healthy donors were enriched and stimulated with CpG-2006 (a) and Epstein–Barr virus (EBV) DNA (TLR9 ligands) (b) in vitro. Gating strategy is described in Fig. 5. Intracellular cytokine level for IL-6, IL-1β, TNFα and monocyte chemoattractant protein-1 (MCP-1) are shown for all three subsets of monocytes. Gray non-stimulated samples, Blue healthy donors, red RA patients. Representative cytometry histograms are representative of ten donors