FIG. 1.

Adherence of bacterial strains to a Caco-2 cell monolayer. (a) Adhesion of Bifidobacterium bifidum MIMBb75 (a and c) and Bifidobacterium pseudocatenulatum NAP32 (b) to a Caco-2 cell monolayer as observed with Giemsa staining under a light microscope. MIMBb75 adhesion was specific to Caco-2 cells: no adhesion was detected on the cover glass underlying Caco-2 cells (c, left). Bars, 5 μm in a and b and 10 μm in c. (b) Quantification of adhesion ability. The numbers above each column refer to the adhesion index (bacterial cells adhered to 100 Caco-2 cells). The data represent the means of at least two independent experiments conducted in duplicate. The vertical bars indicate standard deviations. Bifidobacterium lactis stands for Bifidobacterium animalis subsp. lactis.