Figure 4. Specific suppression of synergistic effects of NOD1 and NOD2 agonists in combination with TLR ligands in oral epithelial cells with siRNA for NF-B p65. Oral epithelial cells were transfected with NF-B- or Lamin-specific siRNA. After 24 hrs, the transfected cells were stimulated with FK156 (100 µg/mL) or muramyldipeptide (MDP) (100 µg/mL) plus FSL-1 (1 nM), Poly I:C (10 µg/mL), lipid A (10 ng/mL), Poly U (1 µg/mL), or CpG DNA (1 µM) for an additional 24 hrs in triplicate. Concentrations of β-defensin 2 in the culture supernatants were determined by ELISA, and expressed as means ± SD. *,#Marked values differed significantly from those obtained with medium alone or from respective cultures stimulated with the indicated ligands, respectively. The results presented are representative of 3 different experiments.