Fig 2.

Effect of Lactobacillus acidophilus NCFM, Lactobacillus helveticus MIMLh5, and the purified S-layer protein (Slay) of MIMLh5 on human epithelial colorectal Caco-2 cells stably transfected with an NF-κB/luciferase reporter vector at baseline (A) or stimulated with 2 ng/ml of IL-1β (B). A recombinant Caco-2 cell layer was incubated with EMEM only (A) or with the addition of IL-1β (B). Bacterial strains were used at an MOI of 1,000 (bacterial cells per Caco-2 cell). S-layer protein was tested at two different concentrations (100 and 10 μg/ml). Data in the histograms are the means (+ standard deviations) from at least three independent experiments conducted in triplicate. Data are reported as percent variation of light emission (relative luminescence units [RLU]), assuming that the value for the corresponding control was 100%. Asterisks indicate statistically significant differences: ***, P < 0.001; **, P < 0.01; *, P < 0.05.