FIGURE 5.

Adherent L. reuteri ATCC PTA 6475 inhibits EPEC binding to HT-29 but not LS174T cells. (A) HT-29 and LS174T cells were incubated with L. reuteri ATCC PTA 6475 or ATCC 53608 for 4 h. Adherent L. reuteri were visualized by immunofluorescence staining with anti-CmbA (PTA 6475) or anti-MUB (ATCC 53608) in green. Cell nuclei were counterstained with DAPI (blue). Merged color images of both channels are shown for HT-29 cells, whereas black-and-white images of the green channel (L. reuteri staining) are displayed for confluent LS174T cells for greater clarity. Shown are representative images from three independent experiments performed in duplicate. Bar = 10 μm. (B) HT-29 and LS174T cells were pre-incubated with ATCC PTA 6475, ATCC 53608, or left untreated (–) for 4 h, non-adherent bacteria were removed, and EPEC was added for 1 h. Cell-associated EPEC were quantified by CFU, and adhesion is expressed as percentage of adherent bacteria relative to the inoculum. Data are shown as means ± SEM from three independent experiments performed in duplicate. ^∗P < 0.05.