Figure 2.

Reduction in trans-epithelial electrical resistance (TER) in T84 cells by purified catalytically active heat-labile enterotoxin (LT). A, Polarized T84 monolayers were treated with LT or with heat-inactivated LT for 3 hours, washed, then monitored for TER over the next 21 hours. Three independent experiments were performed and results were pooled for comparison; graphs show mean ± SEM. Asterisks indicate significance by the Mann-Whitney test (P < 0.05). B, Cells were treated with LT, heat-inactivated LT, the mutant R192G, or the B-subunit for three hours, washed to remove extracellular toxin, then monitored for TER.