Effects of L. gasseri OLL2809 or L13-Ia on an intestinal cell line. A) FACS analysis of MHC class II expression in MODE-K cells incubated with irradiated L. gasseri OLL2809 or L13-Ia; values are expressed as percentages of the maximal fluorescence intensity. Inset, statistical evaluation of MHC class II expression; columns represent the mean ± SD of three independent experiments; **, P < 0.01. B) IL-6 production by MODE-K cells following 24 h stimulation with irradiated bacteria or their metabolites (SupOLL2809 and SupL13-Ia); values are expressed in pg/ml. C) Intracellular GSH concentration in MODE-K cells, expressed in nmoles/mg prot/min (upper panel), and GSHtot amount in spent media, expressed in nmoles/min (lower panel), following 24 h stimulation with irradiated bacteria; columns represent the mean ± SD and are representative of three independent experiments. sup, supernatant from irradiated bacteria incubated for 24 h in RPMI complete medium. **, P < 0.01; ***, P < 0.001.