L- and D, L-SFN are able to significantly suppress MDP-induced SEAP activity in NOD2 WT cells. NOD2 WT cells were treated for 24 h with 0.2 μg/ml MDP in the presence or absence of L- (A) or D, L-SFN (B). Media was collected and added to QUANTI-Blue™ solution and left at room temperature for 40–60 min before being measured using a spectrophotometer at 650 nm. Data shown = mean ± SD, data representative of three independent experiments. + p < 0.05, ++ p < 0.01 comparison to 0 μM –MDP. *p < 0.05, **p < 0.01, ***p < 0.001 comparison to 0 μM + MDP.