Effect of HT-29 intestinal epithelial cells on growth of <i>Lactobacillus</i> strains.

<p>A. <i>Lactobacillus casei</i> ATCC 334 was cultivated in MRS broth overnight, and then inoculated into McCoy’s 5A medium (plain medium), onto HT-29 cells in McCoy’s 5A medium (HT-29 cells), or into McCoy’s 5A medium that had been collected from HT-29 cells after 18 hour incubation (conditioned medium). Bacteria were also inoculated into MRS broth. After 18 hour cultivation, numbers of bacteria were determined by viable counting. Averages of three (conditioned medium), four (plain medium and MRS) or eight (HT-29 cells) replicate samples and standard deviations are shown. cfu = colony forming unit. ***, <i>p</i><0.001; ns, non-significant (one-way Anova followed by Tukey’s Multiple Comparison test). B. <i>Lactobacillus</i> strains were inoculated onto HT-29 cells or into plain medium in 96-well plates. Bacterial growth was measured by absorbance at 595 nm. Averages of four replicate samples and standard deviations are shown. ***, samples differing from the corresponding non-bacteria control, <i>p</i><0.001 (one-way Anova followed by Tukey’s Multiple Comparison test).