The additive effect of TLR2, TLR4, and TLR6 ligation on the production of IL-17 and IL-23. IL-23 (a) and IL-17 (b) production stimulated additively by TLR2, TLR4, and TLR6 ligation. Peripheral blood mononuclear cells from patients with Sjögren's syndrome (n = 5) were cultured with ligands for TLR2 and/or TLR4 and/or TLR6 for 48 hours. The concentrations of IL-23 and IL-17 in the culture supernatants were measured by sandwich enzyme-linked immunosorbent assay. Data are expressed as the mean ± standard deviation. *P < 0.05 compared with nil. #P < 0.05 compared with TLR2 ligand-treated cells. @@P < 0.01 compared with TLR2, TLR4, and TLR6 ligand-treated cells. IL, interleukin; LPS, lipopolysaccharide; PGN, peptidoglycan; TLR, Toll-like receptor.