TJP1 and infection: 3,4-TMAB at 20 μM significantly increased ZO-1 levels (1.8-fold, P=0.0071) compared to infection alone, but at a concentration of 1 mM, levels of ZO-1 reverted to those of infection without pre-treatment, suggesting that 3,4-TMAB may be protective, but only at lower physiologically relevant concentrations [27].