Pre-treating HT29-MTX cells with LAB prior to infection reduces S. Javiana invasion and S. Javiana-induced cytotoxicity. (A, B) HT29-MTX cells were infected with S. Javiana alone (MOI 10) or pre-treated for 1 h with individual LAB (MOE 10) prior to infection with S. Javiana. (A) At 1 h p.i., epithelial cells were washed and adherent S. Javiana were enumerated by plating. (B) At 2 h p.i., monolayers were treated with gentamicin (100 µg/ml) and 30 min later, epithelial cells were lysed and intracellular S. Javiana were enumerated by plating. (C) HT29-MTX cells were pre-treated with LAB (MOE 10) for 1 h prior to infection with S. Javiana (MOI 10) for 2 h. At 2 h p.i., LDH was measured in HT29-MTX cell supernatants and % cytotoxicity was determined. In A and B, number of adherent or intracellular S. Javiana were compared between treatments. In C, % cytotoxicity was compared between treatments. NS indicates no significant difference in S. Javiana adhesion between treatment groups, while different letters (W,X,Y,Z) indicate significant pairwise differences in invasion or cytotoxicity (P < 0.05) between treatments. (SJ = S. Javiana, La = L. acidophilus, Lr = L. rhamnosus, Lc = L. casei, Lm = L. mesenteroides, Lp = L. plantarum, TX = Triton X-treated cells)