Fig. 5.

Basal, but not apical, application of supernatant sample of toxin A-negative, toxin B-positive strain of C. difficile induces loss of TER (a) and increase in permeability to FITC-dextran (b). C. difficilewas cultured anaerobically and supernatant samples were subsequently applied to the apical or basal surface of monolayers of Caco-2 cells grown in transwell inserts. +P < 0·005, #P < 0·002 and *P < 0·0001, versus the rest at relevant time points. The figure represents mean data from three experiments (performed in duplicate). TER, transepithelial electrical resistance.